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Sample records for chitosan coated oil

  1. Preservation Mechanism of Chitosan-Based Coating with Cinnamon Oil for Fruits Storage Based on Sensor Data.

    Science.gov (United States)

    Xing, Yage; Xu, Qinglian; Yang, Simon X; Chen, Cunkun; Tang, Yong; Sun, Shumin; Zhang, Liang; Che, Zhenming; Li, Xihong

    2016-07-18

    The chitosan-based coating with antimicrobial agent has been developed recently to control the decay of fruits. However, its fresh keeping and antimicrobial mechanism is still not very clear. The preservation mechanism of chitosan coating with cinnamon oil for fruits storage is investigated in this paper. Results in the atomic force microscopy sensor images show that many micropores exist in the chitosan coating film. The roughness of coating film is affected by the concentration of chitosan. The antifungal activity of cinnamon oil should be mainly due to its main consistent trans-cinnamaldehyde, which is proportional to the trans-cinnamaldehyde concentration and improves with increasing the attachment time of oil. The exosmosis ratios of Penicillium citrinum and Aspergillus flavus could be enhanced by increasing the concentration of cinnamon oil. Morphological observation indicates that, compared to the normal cell, the wizened mycelium of A. flavus is observed around the inhibition zone, and the growth of spores is also inhibited. Moreover, the analysis of gas sensors indicate that the chitosan-oil coating could decrease the level of O₂ and increase the level of CO₂ in the package of cherry fruits, which also control the fruit decay. These results indicate that its preservation mechanism might be partly due to the micropores structure of coating film as a barrier for gas and a carrier for oil, and partly due to the activity of cinnamon oil on the cell disruption.

  2. Preservation Mechanism of Chitosan-Based Coating with Cinnamon Oil for Fruits Storage Based on Sensor Data

    Science.gov (United States)

    Xing, Yage; Xu, Qinglian; Yang, Simon X.; Chen, Cunkun; Tang, Yong; Sun, Shumin; Zhang, Liang; Che, Zhenming; Li, Xihong

    2016-01-01

    The chitosan-based coating with antimicrobial agent has been developed recently to control the decay of fruits. However, its fresh keeping and antimicrobial mechanism is still not very clear. The preservation mechanism of chitosan coating with cinnamon oil for fruits storage is investigated in this paper. Results in the atomic force microscopy sensor images show that many micropores exist in the chitosan coating film. The roughness of coating film is affected by the concentration of chitosan. The antifungal activity of cinnamon oil should be mainly due to its main consistent trans-cinnamaldehyde, which is proportional to the trans-cinnamaldehyde concentration and improves with increasing the attachment time of oil. The exosmosis ratios of Penicillium citrinum and Aspergillus flavus could be enhanced by increasing the concentration of cinnamon oil. Morphological observation indicates that, compared to the normal cell, the wizened mycelium of A. flavus is observed around the inhibition zone, and the growth of spores is also inhibited. Moreover, the analysis of gas sensors indicate that the chitosan-oil coating could decrease the level of O2 and increase the level of CO2 in the package of cherry fruits, which also control the fruit decay. These results indicate that its preservation mechanism might be partly due to the micropores structure of coating film as a barrier for gas and a carrier for oil, and partly due to the activity of cinnamon oil on the cell disruption. PMID:27438841

  3. Quality attributes and microbial survival on whole cantaloupes with antimicrobial coatings containing chitosan, lauric arginate, cinnamon oil and ethylenediaminetetraacetic acid.

    Science.gov (United States)

    Ma, Qiumin; Zhang, Yue; Critzer, Faith; Davidson, P Michael; Zhong, Qixin

    2016-10-17

    Cantaloupes are susceptible to microbiological contamination in pre- or postharvest environments. Novel intervention strategies, such as antimicrobial coatings, are needed to improve the microbiological safety of cantaloupes. The objective of this study was to prepare whole cantaloupes coated with mixtures containing chitosan, lauric arginate (LAE), cinnamon oil (CO), and ethylenediaminetetraacetic acid (EDTA) and determine survival characteristics of inoculated foodborne pathogens during storage as well as cantaloupe quality attributes. Chitosan coating with 0.1% LAE, 0.1% EDTA, and 1% CO was the most effective for inactivating foodborne pathogens inoculated on cantaloupes. This coating caused a >3logCFU/cm(2) reduction of Escherichia coli O157:H7 and Listeria monocytogenes immediately after coating and reduced Salmonella enterica to below the detection limit during a 14-day storage. Total molds and yeasts also were reduced to the detection limit by the coating. The redness and yellowness of uncoated cantaloupes were significantly higher than coated ones from day 6. The firmness of uncoated cantaloupes and those coated with chitosan only was significantly lower than other treatments from day 10. No significant differences were found in total soluble solids content or weight loss between coated and uncoated cantaloupes. Results showed the potential benefits of applying the coating mixtures to improve the quality and microbiological safety of cantaloupes.

  4. Effects of chitosan-based coatings containing peppermint essential oil on the quality of post-harvest papaya fruit

    Science.gov (United States)

    Edible coatings comprised of antimicrobial polymers based on chitosan are promising technologies to preserve post-harvest fruit quality. In this study, we investigated the potential utility of a coating made from chitosan modified by N-acylation with fatty acid to preserve post-harvest papaya qualit...

  5. A chitosan-based coating with or without clove oil extends the shelf life of cooked pork sausages in refrigerated storage.

    Science.gov (United States)

    Lekjing, Somwang

    2016-01-01

    Chitosan coatings, with and without clove oil, were investigated for effects on quality and shelf life of cooked pork sausages stored at a refrigerated temperature (4±2°C). The various treatments of cooked pork sausages were: untreated (control), coating with 2% chitosan (CS), and coating with a mixture having 2% chitosan and 1.5% clove oil (CS+CO). Various microbiological, physical, chemical and sensory properties were monitored over 25 days of storage. The total viable count, the psychrotrophic bacteria count, the L* value, peroxide value and the thiobarbituric acid reactive substances increased, while the a* value, the b* value, the pH and the sensory scores decreased with storage time, across all treatments. However, these changes were slowest with the CS+CO treatment. Based on sensory evaluation and microbiological quality, the shelf lives were 14 days for control, 20 days for CS, and 20 days for CS+CO treated samples, under refrigerated storage.

  6. A Chitosan Coating Containing Essential Oil from Origanum vulgare L. to Control Postharvest Mold Infections and Keep the Quality of Cherry Tomato Fruit.

    Science.gov (United States)

    Barreto, Tainá A; Andrade, Sonalle C A; Maciel, Janeeyre F; Arcanjo, Narciza M O; Madruga, Marta S; Meireles, Bruno; Cordeiro, Ângela M T; Souza, Evandro L; Magnani, Marciane

    2016-01-01

    The efficacy of an edible chitosan coating (CHI; 4 mg/mL) and Origanum vulgare L. essential oil (OVEO; 1.25 μL/mL) for maintaining the quality of cherry tomato fruit during storage at room (25°C; 12 days) and cold (12°C; 24 days) temperatures was assessed. CHI and OVEO in combination showed in vitro fungicidal effects against R. stolonifer and Aspergillus niger. CHI-OVEO coating reduced the incidence of black mold and soft rot caused by these fungi in artificially contaminated cherry tomato fruit during storage at both temperatures. CHI-OVEO coating delayed the appearance of the first visible signs of black mold and soft rot in artificially contaminated cherry tomato fruit stored at room temperature by 6 days and by more than 9 days in those stored at cold temperature. At the end of storage at room and cold temperature fruit coated with CHI-OVEO showed higher firmness (>2 N/mm) and lower weight loss (>2%) compared to uncoated tomato fruit. CHI-OVEO coating delayed the decrease of lycopene, ascorbic citric acid, glucose and fructose during the storage time assessed at room or cold temperatures. The increase of catechin, myricetin, caffeic and syringic acids was higher (1-9 mg/g) in cherry tomato fruit coated with CHI-OVEO compared to uncoated fruit during the storage at both temperatures studied. CHI-OVEO coating is a feasible treatment for maintaining the storage quality of cherry tomato fruit.

  7. Coatings comprising chitosan and Mentha piperita L. or Mentha × villosa Huds essential oils to prevent common postharvest mold infections and maintain the quality of cherry tomato fruit.

    Science.gov (United States)

    Guerra, Ingrid Conceição Dantas; de Oliveira, Priscila Dinah Lima; Pontes, Alline Lima de Souza; Lúcio, Ana Sílvia Suassuna Carneiro; Tavares, Josean Fechine; Barbosa-Filho, José Maria; Madruga, Marta Suely; de Souza, Evandro Leite

    2015-12-02

    In this study, we evaluated the efficacy of coatings comprising shrimp chitosan (CHI) and Mentha piperita L. (MPEO) or Mentha × villosa Huds (MVEO) essential oils to control mold infections caused by Aspergillus niger, Botrytis cinerea, Penicillium expansum and Rhizopus stolonifer in cherry tomato fruits (Solanum lycopersicum L.) during storage at room temperature (25°C for 12 days) and low temperature (12°C for 24 days). The effects of the coatings on the physicochemical and sensory characteristics of cherry tomato fruits during storage were also assessed. The minimum inhibitory concentration (MIC) of CHI against all test fungi was 8 mg/mL, whereas the MIC for both MPEO and MVEO was 5 μL/mL. Combinations of CHI at 4 mg/mL and MPEO or MVEO at 2.5 or 1.25 μL/mL strongly inhibited the mycelial growth and spore germination of target fungi. The coatings comprising CHI and MPEO or CHI and MVEO at the different tested concentrations delayed the growth of decay-causing fungi in artificially contaminated tomato fruit during storage at either room temperature or low temperature. The assayed coatings preserved the quality of cherry tomato fruit during storage, in terms of physicochemical and sensory attributes. These results indicate that coatings comprising CHI and MPEO or CHI and MVEO represent promising postharvest treatments to prevent common postharvest mold infections in cherry tomato fruit during storage without affecting the quality of the fruit.

  8. Antibacterial and physical effects of modified chitosan based-coating containing nanoemulsion of mandarin essential oil and three non-thermal treatments against Listeria innocua in green beans.

    Science.gov (United States)

    Severino, Renato; Vu, Khanh Dang; Donsì, Francesco; Salmieri, Stephane; Ferrari, Giovanna; Lacroix, Monique

    2014-11-17

    The antimicrobial activity against Listeria innocua of three different combined non-thermal treatments, along with the impact on color and texture on green bean samples, was evaluated. In this study a bioactive coating formulation based on modified chitosan containing 0.05% nanoemulsion of mandarin essential oil was tested in combination with γ-irradiation, UV-C and ozonated water treatments, and the results in terms of antimicrobial activity, color and texture changes, were evaluated during 14 days storage. The combined coating and γ-irradiation treatment gave promising results, showing 3.3 log CFU/g initial microbial reduction, and exhibiting a strong synergistic antimicrobial effect. The treatment based on UV-C and coating formulation allowed a 3 log CFU/g reduction of initial L. innocua population on samples, showing a good residual antimicrobial activity and preventing loss of firmness and color changes during storage. The combined treatment of coating and ozonated water did not show any synergistic or additive antimicrobial effect, but they showed an impact on firmness and color. In conclusion UV-C and γ-irradiation treatments, in combination with the bioactive coating, represent an effective approach to control the growth of L. innocua on vegetable foods.

  9. A chitosan coating containing essential oil from Origanum vulgare L. to control postharvest mold infections and keep the quality of cherry tomato fruit

    Directory of Open Access Journals (Sweden)

    Tainá Barreto

    2016-11-01

    Full Text Available The efficacy of an edible chitosan coating (CHI; 4 mg/mL and Origanum vulgare L. essential oil (OVEO; 1.25 µL/mL for maintaining the quality of cherry tomato fruit during storage at room (25 °C; 12 days and cold (12 °C; 24 days temperatures was assessed. CHI and OVEO in combination showed in vitro fungicidal effects against R. stolonifer and Aspergillus niger. CHI-OVEO coating reduced the incidence of black mold and soft rot caused by these fungi in artificially contaminated cherry tomato fruit during storage at both temperatures by more than. CHI-OVEO coating delayed the appearance of the first visible signs of black mold and soft rot in artificially contaminated cherry tomato fruit stored at room temperature by six days and by more than nine days in those stored at cold temperature. At the end of storage at room and cold temperature fruit coated with CHI-OVEO showed higher firmness ( > 2 N/mm and lower weight loss ( > 2 % compared to uncoated tomato fruit. CHI-OVEO coating delayed the decrease of lycopene, ascorbic citric acid, glucose and fructose during the storage time assessed at room or cold temperatures. The increase of catechin, myricetin, caffeic and syringic acids was higher (1 - 9 mg/g in cherry tomato fruit coated with CHI-OVEO compared to uncoated fruit during the storage at both temperatures studied. CHI-OVEO coating is a feasible treatment for maintaining the storage quality of cherry tomato fruit.

  10. A Chitosan Coating Containing Essential Oil from Origanum vulgare L. to Control Postharvest Mold Infections and Keep the Quality of Cherry Tomato Fruit

    Science.gov (United States)

    Barreto, Tainá A.; Andrade, Sonalle C. A.; Maciel, Janeeyre F.; Arcanjo, Narciza M. O.; Madruga, Marta S.; Meireles, Bruno; Cordeiro, Ângela M. T.; Souza, Evandro L.; Magnani, Marciane

    2016-01-01

    The efficacy of an edible chitosan coating (CHI; 4 mg/mL) and Origanum vulgare L. essential oil (OVEO; 1.25 μL/mL) for maintaining the quality of cherry tomato fruit during storage at room (25°C; 12 days) and cold (12°C; 24 days) temperatures was assessed. CHI and OVEO in combination showed in vitro fungicidal effects against R. stolonifer and Aspergillus niger. CHI-OVEO coating reduced the incidence of black mold and soft rot caused by these fungi in artificially contaminated cherry tomato fruit during storage at both temperatures. CHI-OVEO coating delayed the appearance of the first visible signs of black mold and soft rot in artificially contaminated cherry tomato fruit stored at room temperature by 6 days and by more than 9 days in those stored at cold temperature. At the end of storage at room and cold temperature fruit coated with CHI-OVEO showed higher firmness (>2 N/mm) and lower weight loss (>2%) compared to uncoated tomato fruit. CHI-OVEO coating delayed the decrease of lycopene, ascorbic citric acid, glucose and fructose during the storage time assessed at room or cold temperatures. The increase of catechin, myricetin, caffeic and syringic acids was higher (1–9 mg/g) in cherry tomato fruit coated with CHI-OVEO compared to uncoated fruit during the storage at both temperatures studied. CHI-OVEO coating is a feasible treatment for maintaining the storage quality of cherry tomato fruit. PMID:27877156

  11. PREPARATION OF CHITOSAN COATED METAL AFFINITY CHROMATOGRAPHY ADSORBENT

    Institute of Scientific and Technical Information of China (English)

    AanTianwei; XuWeijiang; 等

    1998-01-01

    A new and an inexpensive adsorbent of chitosan coated silica for immobilized metal affinity chromatography(IMAC) was studied.After a double coating,the chitosan coated on silica beads could be up to 53.4mg/g silica beads.When pH>3.8,the metal ligand Cu2+ was chelated on the coated chitosan with a bound capacity of 14.6mg/g chitosan without introducing iminodiacetic acid(IDA).

  12. Effect of chitosan edible coating incorporated with origanum essential oil on preservation of fresh-cut pineapple%壳聚糖涂膜与牛至精油复配对鲜切菠萝的保鲜作用

    Institute of Scientific and Technical Information of China (English)

    冯可; 胡文忠; 姜爱丽; 萨仁高娃; 徐永平

    2015-01-01

    Objective To study the influence of chitosan edible coating and incorporated with oregano essential oil on preservation of fresh-cut pineapple.Methods The values of the firmness, Vc content, peroxidase (POD), polyphenol oxidase (PPO), catalase (CAT) and lipoxygenase (LOX) activity of fresh-cut pineapple were analyzed by processed with chitosan edible coating incorporated with 0.1%, 0.3% and 0.5% of oregano essential, respectively, with water and chitosan edible coating processing as control.Results The processing of chitosan coating with 0.5% oregano essential oil could slow down softening of the tissue; the processing with 0.1% of oregano essential oil could maintain the decline of Vc content slowly; the POD and CAT activity of fresh cut pineapple were declined when it was processed with chitosan coating containing 0.3% and 0.5% oregano essential oil, and appeared increasing trend under other processing condition. The PPO and LOX activity with chitosan edible coating processing were lower than those of the control. Conclusions Chitosan edible coating incorporation with oregano essential oil would extend shelf-life of fresh-cut pineapple at the condition of keeping nutrition ingredient.%目的:研究壳聚糖涂膜及与牛至精油复配对鲜切菠萝的保鲜的影响。方法在低温环境中,按照0.1%、0.3%和0.5%不同浓度的牛至精油与壳聚糖复配,并分别以水、壳聚糖涂膜处理为对照,分析不同处理方式对鲜切菠萝硬度、Vc 含量、过氧化物酶(POD)、多酚氧化酶(PPO)、过氧化氢酶(CAT)和脂氧合酶(LOX)活性的影响。结果壳聚糖涂膜与0.5%的牛至精油复配后可减缓组织软化;与0.1%牛至精油复配可以维持Vc含量的缓慢降低。在不同处理组中,当含有0.3%和0.5%牛至精油时,鲜切菠萝的POD和CAT活性则呈下降趋势,而其他处理组则显著升高;当含有壳聚糖处理组时,其 PPO和LOX活性则低于对照组。结论壳聚糖与牛至

  13. Lipase entrapment in PVA/Chitosan biodegradable film for reactor coatings

    Energy Technology Data Exchange (ETDEWEB)

    Batista, Karla A. [Departamento de Bioquímica e Biologia Molecular, Laboratório de Química de Proteínas, Universidade Federal de Goiás, Cx. Postal 131, 74001-970, Goiânia, GO (Brazil); Lopes, Flavio Marques [Departamento de Bioquímica e Biologia Molecular, Laboratório de Química de Proteínas, Universidade Federal de Goiás, Cx. Postal 131, 74001-970, Goiânia, GO (Brazil); Unidade Universitária de Ciências Exatas e Tecnológicas, Universidade Estadual de Goiás, Anápolis, GO (Brazil); Yamashita, Fabio [Departamento de Tecnologia de Alimentos e Medicamentos, Laboratório de Tecnologia, Universidade Estadual de Londrina, Cx. Postal 6001, CEP 86051-990, Londrina, PR (Brazil); Fernandes, Kátia Flávia, E-mail: katia@icb.ufg.br [Departamento de Bioquímica e Biologia Molecular, Laboratório de Química de Proteínas, Universidade Federal de Goiás, Cx. Postal 131, 74001-970, Goiânia, GO (Brazil)

    2013-04-01

    This study reports the development and characterization of novel biodegradable film, based on chitosan and polyvinyl alcohol containing lipase entrapped. The films showed a thickness of 70.4 and 79 μm to PVA/Chitosan and PVA/Chitosan/Lipase, respectively. The entrapment of lipase in PVA/Chitosan film resulted in increasing of 69.4% tensile strength (TS), and 52.4% of elongation. SEM images showed the formation of a continuous film, without pores or cracks. The lipase entrapment efficiency was estimated in 92% and the films were repeatedly used for 25 hydrolytic cycles, maintaining 62% of initial activity. The PVA/Chitosan/Lipase film was used for olive oil hydrolysis of high performance. These results indicate that PVA/Chitosan/Lipase is a promising material for biotechnology applications such as triacylglycerol hydrolysis and biodiesel production. - Highlights: ► Development and characterization of PVA/Chitosan biodegradable film ► Lipase immobilization onto PVA/Chitosan film ► PVA/Chitosan/Lipase film for reactor coating ► Olive oil hydrolysis using PVA/Chitosan/Lipase film.

  14. Effect of chitosan coatings on postharvest green asparagus quality.

    Science.gov (United States)

    Qiu, Miao; Jiang, Hengjun; Ren, Gerui; Huang, Jianying; Wang, Xiangyang

    2013-02-15

    Fresh postharvest green asparagus rapidly deteriorate due to its high respiration rate. The main benefits of edible active coatings are their edible characteristics, biodegradability and increase in food safety. In this study, the quality of the edible coatings based on 0.50%, 0.25% high-molecular weight chitosan (H-chitosan), and 0.50%, 0.25% low-molecular weight chitosan (L-chitosan) on postharvest green asparagus was investigated. On the basis of the results obtained, 0.25% H-chitosan and 0.50% L-chitosan treatments ensured lower color variation, less weight loss and less ascorbic acid, decrease presenting better quality of asparagus than other concentrations of chitosan treatments and the control during the cold storage, and prolonging a shelf life of postharvest green asparagus.

  15. Effect of chitosan coating on the characteristics of DPPC liposomes

    Directory of Open Access Journals (Sweden)

    Mohsen M. Mady

    2010-07-01

    Full Text Available Because it is both biocompatible and biodegradable, chitosan has been used to provide a protective capsule in new drug formulations. The present work reports on investigations into some of the physicochemical properties of chitosan-coated liposomes, including drug release rate, transmission electron microscopy (TEM, zeta potential and turbidity measurement. It was found that chitosan increases liposome stability during drug release. The coating of DPPC liposomes with a chitosan layer was confirmed by electron microscopy and the zeta potential of liposomes. The coating of liposomes by chitosan resulted in a marginal increase in the size of the liposomes, adding a layer of (92 ± 27.1 nm. The liposomal zeta potential was found to be increasingly positive as chitosan concentration increased from 0.1% to 0.3% (w/v, before stabilising at a relatively constant value. Turbidity studies revealed that the coating of DPPC liposomes with chitosan did not significantly modify the main phase transition temperature of DPPC at examined chitosan concentrations. The appropriate combination of liposomal and chitosan characteristics may produce liposomes with specific, prolonged and controlled release.

  16. Nanosilica-Chitosan Composite Coating on Cotton Fabrics

    Science.gov (United States)

    Maharani, Dina Kartika; Kartini, Indriana; Aprilita, Nurul Hidayat

    2010-10-01

    Nanosilica-chitosan composite coating on cotton fabrics has been prepared by sol-gel method. The sol-gel procedure allows coating of material on nanometer scale, which several commonly used coating procedure cannot achieve. In addition, sol-gel coating technique can be applied to system without disruption of their structure functionaly. The coating were produced via hidrolysis and condensation of TEOS and GPTMS and then mixed with chitosan. The composite coating on cotton fabrics were characterized with X-Ray Diffraction and Scanning Electron microscopy (SEM) method. The result showed that the coating not changed or disrupted the cotton stucture. The coating result in a clear transparent thin layer on cotton surface. The nanocomposite coating has new applications in daily used materials, especially those with low heat resistance, such as textiles and plastics, and as an environmentally friendly water-repellent substitute for fluorine compounds.

  17. The effect of andiroba oil and chitosan concentration on the physical properties of chitosan emulsion film

    Directory of Open Access Journals (Sweden)

    Vanessa Tiemi Kimura

    2016-01-01

    Full Text Available Abstract Chitosan film is used as a dressing to heal burns. The physical and biological properties of the film can be modified by the addition of phytotherapic compounds. This work used the casting -solvent evaporation technique to prepare chitosan film containing andiroba oil (Carapa guianensis which has anti-inflammatory, antibiotic, and healing properties. The objective of this study was to determine the effect of the concentrations of chitosan and andiroba oil on the physical properties of chitosan films. The emulsion films were evaluated concerning the mechanical properties and fluid handling capacity. Additionally, scanning electron microscopy and thermal analysis were performed. The results showed that the barrier and mechanical properties were affected by the addition of andiroba oil, and these may be modulated as a function of the concentration of oil added to the film. The thermal analysis showed no evidence of chemical interactions between the oil and chitosan.

  18. Development of chitosan-based antimicrobial leather coatings.

    Science.gov (United States)

    Fernandes, Isabel P; Amaral, Joana S; Pinto, Vera; Ferreira, Maria José; Barreiro, Maria Filomena

    2013-10-15

    The development of antimicrobial coatings for footwear components is of great interest both from industry and consumer's point of view. In this work, antimicrobial leather materials were developed taking advantage of chitosan intrinsic antimicrobial activity and film forming capacity. Considering the specificities of the leather tanning industry, different coating technologies, namely drum, calender and spray, were tested, being the best results achieved with the drum. This last approach was further investigated to assess the effect of chitosan content, type of solubilizing acid, and impregnation time on the achieved antimicrobial capacity. Considering chitosan price (economic reasons) and the obtained results (antimicrobial activity and coating effectiveness, as inspected by SEM), the impregnation in the drum using a chitosan content of 1% (w/v) in a formic acid solution during 2h, is proposed as the best option for obtaining leather with antimicrobial capacity.

  19. Synthesis and Characterization of Oil-Chitosan Composite Spheres

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    Wei-Ting Wang

    2013-05-01

    Full Text Available Oil-chitosan composite spheres were synthesized by encapsulation of sunflower seed oil in chitosan droplets, dropping into NaOH solution and in situ solidification. Hydrophilic materials (i.e., iron oxide nanoparticles and lipophilic materials (i.e., rhodamine B or epirubicin could be encapsulated simultaneously in the spheres in a one step process. The diameters of the prepared spheres were 2.48 ± 0.11 mm (pure chitosan spheres, 2.31 ± 0.08 mm (oil-chitosan composites, 1.49 ± 0.15 mm (iron-oxide embedded oil-chitosan composites, and 1.69 ± 0.1 mm (epirubicin and iron oxide encapsulated oil-chitosan composites, respectively. Due to their superparamagnetic properties, the iron-oxide embedded oil-chitosan composites could be guided by a magnet. A lipophilic drug (epirubicin could be loaded in the spheres with encapsulation rate measured to be 72.25%. The lipophilic fluorescent dye rhodamine B was also loadable in the spheres with red fluorescence being observed under a fluorescence microscope. We have developed a novel approach to an in situ process for fabricating oil-chitosan composite spheres with dual encapsulation properties, which are potential multifunctional drug carriers.

  20. Synthesis and characterization of oil-chitosan composite spheres.

    Science.gov (United States)

    Huang, Keng-Shiang; Wang, Chih-Yu; Yang, Chih-Hui; Grumezescu, Alexandru Mihai; Lin, Yung-Sheng; Kung, Chao-Pin; Lin, I-Yin; Chang, Yi-Ching; Weng, Wei-Jie; Wang, Wei-Ting

    2013-05-16

    Oil-chitosan composite spheres were synthesized by encapsulation of sunflower seed oil in chitosan droplets, dropping into NaOH solution and in situ solidification. Hydrophilic materials (i.e., iron oxide nanoparticles) and lipophilic materials (i.e., rhodamine B or epirubicin) could be encapsulated simultaneously in the spheres in a one step process. The diameters of the prepared spheres were 2.48 ± 0.11 mm (pure chitosan spheres), 2.31 ± 0.08 mm (oil-chitosan composites), 1.49 ± 0.15 mm (iron-oxide embedded oil-chitosan composites), and 1.69 ± 0.1 mm (epirubicin and iron oxide encapsulated oil-chitosan composites), respectively. Due to their superparamagnetic properties, the iron-oxide embedded oil-chitosan composites could be guided by a magnet. A lipophilic drug (epirubicin) could be loaded in the spheres with encapsulation rate measured to be 72.25%. The lipophilic fluorescent dye rhodamine B was also loadable in the spheres with red fluorescence being observed under a fluorescence microscope. We have developed a novel approach to an in situ process for fabricating oil-chitosan composite spheres with dual encapsulation properties, which are potential multifunctional drug carriers.

  1. Superhydrophobic chitosan-based coatings for textile processing

    Energy Technology Data Exchange (ETDEWEB)

    Ivanova, N.A., E-mail: NAI-72@yandex.ru [Ivanovo State Textile Academy, F. Engels Avenue 21, 153000 Ivanovo (Russian Federation); Philipchenko, A.B. [Kazan State Medical University, Butlerova 49, 420012 Kazan, Tatarstan (Russian Federation)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer Chitosan nanoparticles can be used for design of the superhydrophobic anti-bacterial textile. Black-Right-Pointing-Pointer Spraying the nanoparticle dispersion allows one to get multiscale textured coating. Black-Right-Pointing-Pointer Relative number of fluoroanions per elementary unit of chitosan plays the crucial role in the structure of aggregates and coating wettability. - Abstract: A simple method to design the superhydrophobic anti-bacterial textile for biomedical applications was developed. For the coating formulation the spraying of nanoparticles dispersion over the textile sample was applied, allowing the way to get multiscale textured layer on a top of cotton fabric. The anti-bacterial functionality of coating is supported by using chitosan-based nanoparticles. In our approach the fabrication of nanoparticles was based on electrostatic interaction between amine group of chitosan and negatively charged fluoroanion. It was demonstrated that the relative number of fluoroanions per elementary unit of chitosan plays the crucial role in the structure of aggregates in the coating and its wettability as well as in durability of coatings in contact with aqueous media.

  2. Chitosan-Coated Magnetic Nanoparticles with Low Chitosan Content Prepared in One-Step

    Directory of Open Access Journals (Sweden)

    Yolanda Osuna

    2012-01-01

    Full Text Available Chitosan-coated magnetic nanoparticles (CMNP were obtained at 50°C in a one-step method comprising coprecipitation in the presence of low chitosan content. CMNP showed high magnetization and superparamagnetism. They were composed of a core of 9.5 nm in average diameter and a very thin chitosan layer in accordance with electron microscopy measurements. The results from Fourier transform infrared spectrometry demonstrated that CMNP were obtained and those from thermogravimetric analysis allowed to determine that they were composed of 95 wt% of magnetic nanoparticles and 5 wt% of chitosan. 67% efficacy in the Pb+2 removal test indicated that only 60% of amino groups on CMNP surface bound to Pb, probably due to some degree of nanoparticle flocculation during the redispersion. The very low weight ratio chitosan to magnetic nanoparticles obtained in this study, 0.053, and the high yield of the precipitation reactions (≈97% are noticeable.

  3. Mechanical properties of paper sheets coated with chitosan nanoparticle

    Science.gov (United States)

    Fithriyah, Nurul Hidayati; Erdawati

    2014-03-01

    Chitosan were selected as cellulose raw material to prepare coating solutions. The morphology, physical characteristics and chemical surface properties of the coatings are discussed in this paper. Different concentrations of chitosan (1-5% w/w) and deposited solution layer (0.5-1.00 μm) were used to obtain coated papers with thicknesses varying between 0.062-0.068 μm. The percentages of coating agent impregnated inside paper were also calculated from the apparent density of coated paper and the density of self-supported films prepared in the same conditions but deposited on an inert and smooth Plexiglass support. These percentages of impregnation ranged from 4.8 to 63.3% and increased as following: chitosan chitosan nanoparticle. The resulting absorption rates indicated significant differences as a function of the nature of coating agent and confirmed results obtained for the percentage of impregnation. To explain differences in the behaviour of coating solutions, it was finally concluded that not only their viscosity must be taken into account but also their affinity toward paper.

  4. Effect of chitosan-based edible coating on preservation of white shrimp during partially frozen storage.

    Science.gov (United States)

    Wu, Shengjun

    2014-04-01

    Chitosan and chitooligosaccharides are preservatives with proven antibacterial activity, while glutathione has antioxidant activity. This study investigated the effects of chitosan coating combined with chitooligosaccharides and glutathione (0.8% glutathione+1% chitooligosaccharides+1% chitosan) on preservation of white shrimp (Penaeus vannamei) during partially frozen storage. Chitosan-based coating treatments effectively inhibited bacterial growth, reduced total volatile basic nitrogen and malondialdehyde, and basically maintained the sensory properties of white shrimp (P. vannamei) during partially frozen storage. Therefore, chitosan-based edible coating combined with chitooligosaccharides and glutathione could be a promising antimicrobial and oxidant method to prevent metamorphism of white shrimp with extended shelf life.

  5. Pretreatment of Palm Oil Mill Effluent (POME Using Magnetic Chitosan

    Directory of Open Access Journals (Sweden)

    N. Saifuddin

    2011-01-01

    Full Text Available Chitosan is a natural organic polyelectrolyte of high molecular weight and charge density; obtained from deacetylation of chitin. This study explored the potential and effectiveness of applying chitosan-magnetite nanocomposite particles as a primary coagulant and flocculent, in comparison with chitosan for pre-treatment of palm oil mill effluent (POME. A series of batch coagulation processes with chitosan-magnetite nanocomposite particles and chitosan under different conditions, i.e. dosage and pH were conducted, in order to determine their optimum conditions. The performance was assessed in terms of turbidity, total suspended solids (TSS and chemical oxygen demand (COD reductions. Chitosan-magnetite particles showed better parameter reductions with much lower dosage consumption, compared to chitosan, even at the original pH of POME, i.e. 4.5. At pH 6, the optimum chitosan-magnetite dosage of 250 mg/L was able to reduce turbidity, TSS and COD levels by 98.8%, 97.6% and 62.5% respectively. At this pH, the coagulation of POME by chitosan-magnetite was brought by the combination of charge neutralization and polymer bridging mechanism. On the other hand, chitosan seems to require much higher dosage, i.e. 370 mg/L to achieve the best turbidity, TSS and COD reductions, which were 97.7%, 91.7% and 42.70%, respectively. The synergistic effect of cationic character of both the chitosan amino group and the magnetite ion in the pre-treatment process for POME brings about enhanced performance for effective agglomeration, adsorption and coagulation.

  6. Alginate Hydrogels Coated with Chitosan for Wound Dressing

    Directory of Open Access Journals (Sweden)

    Maria Cristina Straccia

    2015-05-01

    Full Text Available In this work, a coating of chitosan onto alginate hydrogels was realized using the water-soluble hydrochloride form of chitosan (CH-Cl, with the dual purpose of imparting antibacterial activity and delaying the release of hydrophilic molecules from the alginate matrix. Alginate hydrogels with different calcium contents were prepared by the internal setting method and coated by immersion in a CH-Cl solution. Structural analysis by cryo-scanning electron microscopy was carried out to highlight morphological alterations due to the coating layer. Tests in vitro with human mesenchymal stromal cells (MSC were assessed to check the absence of toxicity of CH-Cl. Swelling, stability in physiological solution and release characteristics using rhodamine B as the hydrophilic model drug were compared to those of relative uncoated hydrogels. Finally, antibacterial activity against Escherichia coli was tested. Results show that alginate hydrogels coated with chitosan hydrochloride described here can be proposed as a novel medicated dressing by associating intrinsic antimicrobial activity with improved sustained release characteristics.

  7. Alginate hydrogels coated with chitosan for wound dressing.

    Science.gov (United States)

    Straccia, Maria Cristina; d'Ayala, Giovanna Gomez; Romano, Ida; Oliva, Adriana; Laurienzo, Paola

    2015-05-11

    In this work, a coating of chitosan onto alginate hydrogels was realized using the water-soluble hydrochloride form of chitosan (CH-Cl), with the dual purpose of imparting antibacterial activity and delaying the release of hydrophilic molecules from the alginate matrix. Alginate hydrogels with different calcium contents were prepared by the internal setting method and coated by immersion in a CH-Cl solution. Structural analysis by cryo-scanning electron microscopy was carried out to highlight morphological alterations due to the coating layer. Tests in vitro with human mesenchymal stromal cells (MSC) were assessed to check the absence of toxicity of CH-Cl. Swelling, stability in physiological solution and release characteristics using rhodamine B as the hydrophilic model drug were compared to those of relative uncoated hydrogels. Finally, antibacterial activity against Escherichia coli was tested. Results show that alginate hydrogels coated with chitosan hydrochloride described here can be proposed as a novel medicated dressing by associating intrinsic antimicrobial activity with improved sustained release characteristics.

  8. Chitosan-Coated Collagen Membranes Promote Chondrocyte Adhesion, Growth, and Interleukin-6 Secretion

    Directory of Open Access Journals (Sweden)

    Nabila Mighri

    2015-11-01

    Full Text Available Designing scaffolds made from natural polymers may be highly attractive for tissue engineering strategies. We sought to produce and characterize chitosan-coated collagen membranes and to assess their efficacy in promoting chondrocyte adhesion, growth, and cytokine secretion. Porous collagen membranes were placed in chitosan solutions then crosslinked with glutaraldehyde vapor. Fourier transform infrared (FTIR analyses showed elevated absorption at 1655 cm-1 of the carbon–nitrogen (N=C bonds formed by the reaction between the (NH2 of the chitosan and the (C=O of the glutaraldehyde. A significant peak in the amide II region revealed a significant deacetylation of the chitosan. Scanning electron microscopy (SEM images of the chitosan-coated membranes exhibited surface variations, with pore size ranging from 20 to 50 µm. X-ray photoelectron spectroscopy (XPS revealed a decreased C–C groups and an increased C–N/C–O groups due to the reaction between the carbon from the collagen and the NH2 from the chitosan. Increased rigidity of these membranes was also observed when comparing the chitosan-coated and uncoated membranes at dried conditions. However, under wet conditions, the chitosan coated collagen membranes showed lower rigidity as compared to dried conditions. Of great interest, the glutaraldehyde-crosslinked chitosan-coated collagen membranes promoted chondrocyte adhesion, growth, and interleukin (IL-6 secretion. Overall results confirm the feasibility of using designed chitosan-coated collagen membranes in future applications, such as cartilage repair.

  9. Hypoglycemic efficacy of chitosan-coated insulin liposomes after oral administration in mice

    Institute of Scientific and Technical Information of China (English)

    Zheng-hong WU; Qi-neng PING; Yi WEI; Jia-ming LAI

    2004-01-01

    AIM: To evaluate the hypoglycemic efficacy of insulin liposomes coated by chitosan with different molecular weights and concentrations after oral administration in mice. METHODS: Insulin-liposomes were prepared by reversed-phase evaporation. Chitosan coating was carried out by incubation of the liposomal suspensions with the chitosan solution. The hypoglycemic efficacies of chitosan-coated insulin liposomes were investigated by monitoring the blood glucose level using the glucose oxidase method after oral administration to healthy mice. RESULTS:In all the insulin liposomes, the insulin liposomes coated by 0.2 % chitosan (M. 1000 kDa) showed a better hypoglycemic efficacy as compared with the other liposomes coated by chitosan. The minimum blood glucose level was 15.1%±6.0 % of the initial (n=6). The hypoglycemic efficacy lasted for 4 h after oral administration to mice.CONCLUSION: Chitosan-coated liposomes could reduce tryptic digestion on insulin, and enhance enteral absorption of insulin. The molecular weights and concentrations of chitosan had significant effects on hypoglycemic efficacy of chitosan-coated insulin liposomes after oral administration to healthy mice.

  10. Improved postharvest quality in patagonian squash (Cucurbita moschata) coated with radiation depolymerized chitosan

    Energy Technology Data Exchange (ETDEWEB)

    Pugliese, Maria Alicia; Goitia, Maria Teresa [Laboratorio de Investigaciones Basicas Aplicadas en Quitina, Departamento de Quimica, Universidad Nacional del Sur. Avenida Alem 1253, B8000CPB Bahia Blanca (Argentina); Yossen, Mariana [Instituto de Desarrollo Tecnologico para la Industria Quimica (INTEC), CONICET-Universidad Nacional del Litoral, Ruta Nacional 168-Paraje ' El Pozo' , 3000 Santa Fe (Argentina); Cifone, Norma; Agullo, Enrique [Laboratorio de Investigaciones Basicas Aplicadas en Quitina, Departamento de Quimica, Universidad Nacional del Sur. Avenida Alem 1253, B8000CPB Bahia Blanca (Argentina); Andreucetti, Noemi, E-mail: andreuce@criba.edu.ar [Laboratorio de Radioisotopos, Departamento de Quimica, Universidad Nacional del Sur, Avenida Alem 1253, B8000CPB Bahia Blanca (Argentina)

    2011-12-15

    Different molecular weight chitosans were evaluated on the decay of coated Anquito squashes (Cucurbita moschata) as well as the maintenance of the fruit quality along five storage months. The original chitosan (Mw=391 kDa, 83% DD), was depolymerized by gamma radiation. Apart from chain scission, other chemical changes were not detected by FTIR or UV-vis analyses. The molecular weight characterization of chitosans was done by size exclusion chromatography with dual light scattering and concentration detection (SEC-MALLS-RI). The coating effectiveness was evaluated on the following parameters: fungal decay incidence, weight loss, firmness, total reducing sugar, soluble solid, flesh color, carotene content, pH and titratable acidity. No sign of fungal decay was observed in squashes coated with 122 and 56 kDa chitosans, which were also the most effective treatments in reducing the weight loss. The chitosan with Mw=122 kDa was also the best treatment considering firmness, internal aspect, sugar and carotene content. Then, radiation degraded chitosan was better in C. moschata preservation than the original chitosan. - Highlights: > Original Chitosan was radiation depolymerized producing chitosans with lower molecular weights. > Gamma-irradiated chitosans only exhibit chain scission. > SEC-MALLS-RI chromatography is a useful tool in molecular weight analysis. > Depolymerized chitosans were the best in maintaining the quality and the storage life of coated squashes.

  11. Two-step preparation of nano-scaled magnetic chitosan particles using Triton X-100 reversed-phase water-in-oil microemulsion system

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Zhengkun; Jiang, Feihong [College of Food Science and Engineering, Northwest A and F University, Yangling, Shaanxi 712100 (China); Lee, Tung-Ching, E-mail: lee@aesop.rutgers.edu [Department of Food Science, Rutgers, the State University of New Jersey, 65 Dudley Road, New Brunswick, NJ 08901 (United States); Yue, Tianli, E-mail: yuetl305@nwsuaf.edu.cn [College of Food Science and Engineering, Northwest A and F University, Yangling, Shaanxi 712100 (China)

    2013-12-25

    Highlights: •A new two-step route for nano-scaled magnetic chitosan particles preparation. •Triton X-100 reversed-phase microemulsion system was used for chitosan coating. •Narrow size distribution of magnetic chitosan nanoparticles was achieved. •Quantitative evaluation of recoverability for the magnetic chitosan nanoparticles. -- Abstract: A new two-step route for the preparation of nano-scaled magnetic chitosan particles has been developed, different from reported one-step in situ preparation and two-step preparation method of reversed-phase suspension, Triton X-100 reversed-phase water-in-oil microemulsion encapsulation method was employed in coating the pre-prepared Fe{sub 3}O{sub 4} nanoparticles with chitosan. The resultant magnetic chitosan particles owned a narrow size distribution ranging from 50 to 92 nm. X-ray diffraction patterns (XRD) indicated that the chitosan coating procedure did not change the spinal structure of Fe{sub 3}O{sub 4} magnetic nanoparticles. The results of Fourier transform infrared (FTIR) analysis and thermogravimetric analysis (TGA) demonstrated that the chitosan was coated on Fe{sub 3}O{sub 4} nanoparticles and its average mass content was ∼50%. The saturated magnetization of the magnetic Fe{sub 3}O{sub 4}/chitosan nanoparticles reached 18.62 emu/g, meanwhile, the nanoparticles showed the characteristics of superparamagnetism. The magnetic chitosan nanoparticles showed a high recoverability of 99.99% in 10 min when pH exceeded 4. The results suggested that the as-prepared magnetic chitosan particles were nano-scaled with a narrow size distribution and a high recoverability.

  12. Enhanced water vapour barrier and grease resistance of paper bilayer-coated with chitosan and beeswax.

    Science.gov (United States)

    Zhang, Weiwei; Xiao, Huining; Qian, Liying

    2014-01-30

    In order to overcome the deficiencies of single layer coating, bilayer coated papers were prepared by two separate coating procedures using various combinations of proteins or polysaccharides with beeswax. Among those combinations, chitosan-beeswax bilayer coated paper showed the best water vapour barrier property. It was observed that as the concentration of chitosan solution increased from 1.0 to 3.0 wt%, its water vapour transport rate (WVTR) decreased from 171.6 to 52.8 g/m(2)/d but using reduced beeswax coating weight (from 10.1 to 4.9 g/m(2)). It also displayed an enhanced performance of grease resistance. Scanning electron microscopy (SEM) showed that beeswax layer was fitted to chitosan layer so closely that these two layers are indistinguishable. Confocal laser scanning microscope (CLSM) further confirmed the existence of an integrated chitosan film between beeswax layer and paper base and a thin composite layer consisting of chitosan and beeswax.

  13. Electrolytic deposition of calcium phosphate/chitosan coating on titanium alloy: Growth kinetics and influence of current density, acetic acid, and chitosan

    NARCIS (Netherlands)

    Wang, Jiawei; Apeldoorn, van Aart; Groot, de Klaas

    2006-01-01

    Electrolytically deposited calcium phosphate/chitosan coating demonstrated good bone marrow stromal cell attachment. The aim of this study was to understand the coating's growth kinetics as well as the effects of current density, acetic acid, and chitosan on the coating's formation. The scanning ele

  14. Encapsulation of brewers yeast in chitosan coated carrageenan microspheres by emulsification/thermal gelation.

    Science.gov (United States)

    Raymond, Marie-Christine; Neufeld, Ronald J; Poncelet, Denis

    2004-05-01

    Brewers yeast was encapsulated in kappa-carrageenan microspheres using an emulsification-thermal gelation approach. Due to heat sensitivity of the yeast at temperatures in excess of 36 degrees C, mixtures of low and high gelation temperature carrageenans were tested to obtain a blend yielding a gelation temperature under 40 degrees C. A 20:80 dispersion of 2% carrageenan sol containing cells, in warm canola oil, produced microspheres upon cooling, with a mean diameter of 450 microm and narrow size dispersion (span of 1.2). Application of a chitosan membrane coat to minimize cell release, increased the mean microsphere diameter to 700 microm, due to the coat thickness and swelling of the microspheres. This diameter was designed so as to minimize mass transfer limitations. Batch fermentations were carried out in a 3 L reactor on a commercial wort medium. Cell loading was 10(7) cells mL(-1) microspheres, and cell "burst" release was observed upon inoculation into fresh medium, whether microspheres were coated or not. The kinetics of intra- and extracapsular cell growth were determined. Increased concentrations of extracapsular free cells could be accounted for by growth in the wort medium, and by ongoing release from the gel microspheres, whether coated or not. Cell release from chitosan-coated carrageenan microspheres was less than that from uncoated microspheres, likely due to retention by the membrane coat. Growth kinetics and alpha-amino nitrogen consumption of encapsulated yeast were higher than that of free cells, and differences in alcohol and ester profiles were also observed, likely due to modified metabolism of the encapsulated yeast.

  15. Extending Shelf Life of Chilled Pork by Combination of Chitosan Coating With Spice Extracts

    Institute of Scientific and Technical Information of China (English)

    XIA Xiufang; KONG Baohua

    2008-01-01

    The effects of spices (cinnamon, rosemary, clove) extracts and chitosan on microbiological growth, drip loss, color, and lipid oxidation of fresh chilled meat stored for 28 days at 4"C were investigated. There were four treatments: control, coated with spices(cimmamon 1.5g·L-1+rosemary 1.5·L-1+colve 1.0 g·L-1),coated with 0.5% chitosan,coated with spices and chitosan.Chitosan coating resulted in significant inhibition of microbial growth (P<0.05), while the lowest microbial counts were obtained in the samples containing both chitosan and spices, indicating a possible synergistic effect. Chitosan and its combinations with spices also showed the most intense antioxidative effect when compared to the controls (P<0.05). Meanwhile, chitosan coating could decrease water loss and keep better color of chilled meat. The combined spice extracts and chitosan coating could effectively extend the shelf life of chilled meat.

  16. Inactivation of salmonella on tomato stem scars by edible chitosan and organic Acid coatings.

    Science.gov (United States)

    Jin, T; Gurtler, J B

    2012-08-01

    This study was conducted to investigate the efficacy of antimicrobial coatings for inactivation of Salmonella on the surface of tomato stem scars. Scars were inoculated with a four-strain cocktail of Salmonella (serovars Montevideo, Newport, Saintpaul, and Typhimurium) and coated with acid-chitosan solutions. The chitosan coating with three acids (3A plus chitosan), the chitosan coating with one acid, and the three-acid solution without chitosan reduced the populations of Salmonella by 6.0, 3.6, and 5.3 log CFU per stem scar, respectively. Addition of allyl isothiocyanate (10 μl/ml) to the 3A plus chitosan coating did not significantly increase (P > 0.05) the antimicrobial efficacy. Although the populations of Salmonella in the controls (ca. 7.5 log CFU per stem scar) did not change significantly throughout the 14-day storage period at 10° C, Salmonella cells were reduced to undetectable levels (coating after two days of storage, and no growth was observed for the remaining storage period. Results from this study demonstrate that coatings of acid plus chitosan provide an alternative antimicrobial intervention for decontamination of tomatoes.

  17. Chitosan-aprotinin coated liposomes for oral peptide delivery: Development, characterisation and in vivo evaluation.

    Science.gov (United States)

    Werle, Martin; Takeuchi, Hirofumi

    2009-03-31

    In order to improve the systemic uptake of therapeutic peptides/proteins after oral administration, the polymer-protease inhibitor conjugate chitosan-aprotinin was synthesised and polyelectrolyte complexes between negatively charged multilamellar vesicles (MLV) and positively charged chitosan-aprotinin conjugate were prepared. It could be demonstrated that chitosan-aprotinin was capable of significantly inhibiting Trypsin in vitro in concentrations of 0.05% and 0.1%, whereas no inhibition was observed in the presence of 0.1% chitosan. The size range of the prepared MLV was between 3 and 4.5microm and the initially negative zeta potential (ca. -90mV) of the core liposomes switched to a positive value after polymer coating (ca. +40mV). Confocal laser microscopy studies showed comparable mucoadhesive properties of chitosan-aprotinin coated MLV and chitosan coated MLV. In comparison to calcitonin in solution, the area above the blood calcium concentration-time curve (AAC) after oral administration of calcitonin loaded chitosan coated MLV to rats increased around 11-fold, and around 15-fold in the case of calcitonin loaded chitosan-aprotinin coated MLV. Data gained in the current study are believed to contribute to the development of novel polymer-protease inhibitor based delivery systems.

  18. Evaluation of Chitosan-Starch-Based Edible Coating To Improve the Shelf Life of Bod Ljong Cheese.

    Science.gov (United States)

    Mei, Jun; Guo, Qizhen; Wu, Yan; Li, Yunfei

    2015-07-01

    The objective of this work was to evaluate the effectiveness of antimicrobial edible coatings to improve the quality of Bod ljong cheese throughout 25 days of storage. Coatings were prepared using chitosan, water chestnut starch, and glycerol as a base matrix, together with several combinations of antimicrobial substances: Cornus officinalis fruit extract (COFE), pine needle essential oil (PNEO), and nisin. Application of coating on cheese decreased water loss, lipid oxidation, changes in headspace gas composition, and color. Moreover, the edible coatings with COFE or PNEO had increased antimicrobial activity and did not permit growth of microorganisms. COFE and PNEO are manufactured from food-grade materials so they can be consumed as an integral part of the cheese, which represents a competitive advantage over nonedible coatings.

  19. Effects of laminin-coated carbon nanotube/chitosan fibers on guided neurite growth.

    Science.gov (United States)

    Huang, Yi-Cheng; Hsu, Sung-Hao; Kuo, Wen-Chun; Chang-Chien, Cheng-Lun; Cheng, Henrich; Huang, Yi-You

    2011-10-01

    This study assesses the ability and potential of carbon nanotube (CNT)/chitosan to guide axon re-growth after nerve injuries. The CNT/chitosan fibers were produced via the coagulation and hydrodynamic focusing method. Fiber width and morphology were adjusted using such parameters as syringe pumping rate and the coagulant used. The CNT/chitosan fiber diameters were 50-300 μm for syringe pumping rates of 6-48 mL/h. Polyethylene glycol/NaOH (25%, w/w) solution was a suitable coagulant for forming fibers with small diameters. Physical property tests demonstrate that the CNT/chitosan composites had superior tensile strength and electrical conductivity compared with those of chitosan alone. The MTT and LDH tests reveal that CNT/chitosan composites were not cytotoxic. To improve the neural cell affinity of CNT/chitosan fibers, laminin was incorporated onto fiber surfaces via the oxygen plasma technique; cell adhesion ratio increased significantly from 3.5% to 72.2% with this surface modification. Immunofluorescence staining and SEM imaging indicate that PC12 cells adhered successfully and grew on the laminin (LN)-coated CNT/chitosan films and fibers. Experimental results show that PC12 grown on LN-coated CNT/chitosan fibers in vitro extend longitudinally oriented neurites in a manner similar to that of native peripheral nerves. With the inherent electrical properties of CNTs, oriented CNT/chitosan fibers have a potential for use as nerve conduits in nerve tissue engineering.

  20. Preparation of chitosan-coated polyethylene packaging films by DBD plasma treatment.

    Science.gov (United States)

    Theapsak, Siriporn; Watthanaphanit, Anyarat; Rujiravanit, Ratana

    2012-05-01

    Polyethylene (PE) packaging films were coated with chitosan in order to introduce the antibacterial activity to the films. To augment the interaction between the two polymers, we modified the surfaces of the PE films by dielectric barrier discharge (DBD) plasma before chitosan coating. After that the plasma-treated PE films were immersed in chitosan acetate solutions with different concentrations of chitosan. The optimum plasma treatment time was 10 s as determined from contact angle measurement. Effect of the plasma treatment on the surface roughness of the PE films was investigated by atomic force microscope (AFM) while the occurrence of polar functional groups was observed by X-ray photoelectron spectroscope (XPS) and Fourier transformed infrared spectroscope (FTIR). It was found that the surface roughness as well as the occurrence of oxygen-containing functional groups (i.e., C═O, C-O, and -OH) of the plasma-treated PE films increased from those of the untreated one, indicating that the DBD plasma enhanced hydrophilicity of the PE films. The amounts of chitosan coated on the PE films were determined after washing the coated films in water for several number of washing cycles prior to detection of the chitosan content by the Kjaldahl method. The amounts of chitosan coated on the PE films were constant after washing for three times and the chitosan-coated PE films exhibited appreciable antibacterial activity against Escherichia coli and Staphylococcus aureus. Hence, the obtained chitosan-coated PE films could be a promising candidate for antibacterial food packaging.

  1. Chitosan coating of copper nanoparticles reduces in vitro toxicity and increases inflammation in the lung

    Science.gov (United States)

    Worthington, Kristan L. S.; Adamcakova-Dodd, Andrea; Wongrakpanich, Amaraporn; Mudunkotuwa, Imali A.; Mapuskar, Kranti A.; Joshi, Vijaya B.; Guymon, C. Allan; Spitz, Douglas R.; Grassian, Vicki H.; Thorne, Peter S.; Salem, Aliasger K.

    2013-10-01

    Despite their potential for a variety of applications, copper nanoparticles induce very strong inflammatory responses and cellular toxicity following aerosolized delivery. Coating metallic nanoparticles with polysaccharides, such as biocompatible and antimicrobial chitosan, has the potential to reduce this toxicity. In this study, copper nanoparticles were coated with chitosan using a newly developed and facile method. The presence of coating was confirmed using x-ray photoelectron spectroscopy, rhodamine tagging of chitosan followed by confocal fluorescence imaging of coated particles and observed increases in particle size and zeta potential. Further physical and chemical characteristics were evaluated using dissolution and x-ray diffraction studies. The chitosan coating was shown to significantly reduce the toxicity of copper nanoparticles after 24 and 52 h and the generation of reactive oxygen species as assayed by DHE oxidation after 24 h in vitro. Conversely, inflammatory response, measured using the number of white blood cells, total protein, and cytokines/chemokines in the bronchoalveolar fluid of mice exposed to chitosan coated versus uncoated copper nanoparticles, was shown to increase, as was the concentration of copper ions. These results suggest that coating metal nanoparticles with mucoadhesive polysaccharides (e.g. chitosan) could increase their potential for use in controlled release of copper ions to cells, but will result in a higher inflammatory response if administered via the lung.

  2. Modification of granular activated carbon surface by chitosan coating for geosmin removal: sorption performances.

    Science.gov (United States)

    Vinitnantharat, S; Rattanasirisophon, W; Ishibashi, Y

    2007-01-01

    This study presents the results of the sorption performances for geosmin removal by sorption onto granular activated carbons (GAC) manufactured from different raw materials of coconut shell and bituminous coal. The surface of GAC was modified by chitosan coating. The 90% deacetylated chitosan flakes were used for coating on GAC with the GAC: chitosan ratio of 5:1. The surface of GAC was characterised by scanning electron microscope (SEM) analysis, Fourier transform infrared spectroscopy and measurement of the pH solution of GAC samples. The sorption of geosmin onto the chitosan for both uncoated and coated GACs could be described by the Freundlich adsorption model. Data revealed that the sequence of Freundlich constant (K(F)) was chitosan coated bitominous coal (CB) > uncoated bituminous coal (UB) > chitos approximately equal to an coated coconut shell (CC) approximately equal to uncoated coconut shell (UC). The bituminous coal based GAC with chitosan coating had a maximum capacity of 23.57 microg/g which was approximately two-fold of uncoated bituminous coal based GAC. Two simplified kinetic models, pseudo-first order and pseudo-second order, were tested to investigate the sorption mechanisms. It was found that the intraparticle diffusion was a rate controlling step for the sorption and followed the pseudo-second order equation.

  3. Effect of chitosan coating on a bacteria-based alginate microrobot.

    Science.gov (United States)

    Park, Sung Jun; Lee, Yu Kyung; Cho, Sunghoon; Uthaman, Saji; Park, In-Kyu; Min, Jung-Joon; Ko, Seong Young; Park, Jong-Oh; Park, Sukho

    2015-04-01

    To develop an efficient bacteria-based microrobot, first, therapeutic bacteria should be encapsulated into microbeads using biodegradable and biocompatible materials; second, the releasing rate of the encapsulated bacteria for theragnostic function should be regulated; and finally, flagellated bacteria should be attached on the microbeads to ensure the motility of the microrobot. For the therapeutic bacteria encapsulation, an alginate can be a promising candidate as a biodegradable and biocompatible material. Owing to the non-regulated releasing rate of the encapsulated bacteria in alginate microbeads and the weak attachment of flagellated bacteria on the surface of alginate microbeads, however, the alginate microbeads cannot be used as effective cargo for a bacteria-based microrobot. In this paper, to enhance the stability of the bacteria encapsulation and the adhesion of flagellated bacteria in alginate microbeads, we performed a surface modification of alginate microbeads using chitosan coating. The bacteria-encapsulated alginate microbeads with 1% chitosan coating maintained their structural integrity up to 72 h, whereas the control alginate microbead group without chitosan coating showed severe degradations after 24 h. The chitosan coating in alginate microbeads shows the enhanced attachment of flagellated bacteria on the surface of alginate microbeads. The bacteria-actuated microrobot with the enhanced flagellated bacteria attachment could show approximately 4.2 times higher average velocities than the control bacteria-actuated microrobot without chitosan coating. Consequently, the surface modification using chitosan coating enhanced the structural stability and the motility of the bacteria-based alginate microrobots.

  4. In vitro corrosion behavior and cytotoxicity property of magnesium matrix composite with chitosan coating

    Institute of Scientific and Technical Information of China (English)

    戴翌龙; 余琨; 陈良建; 陈畅; 乔雪岩; 颜阳

    2015-01-01

    Mg-6%Zn-10%β-Ca3(PO4)2 composite was prepared through powder metallurgy methods with different chitosan coatings on its surface. The properties of the chitosan coatings on the surface of Mg-6%Zn-10%β-Ca3(PO4)2 composite, such as the adhesion ability, the corrosion behavior and the cytotoxicity properties, were investigated, and the microstructure of the chitosan coating was observed by scanning electron microscope (SEM). The results show that chitosan coating improves the corrosion resistance of the magnesium composite specimens significantly. Mg-6%Zn-10%β-Ca3(PO4)2 composite specimens exhibit good corrosion resistance and low pH values in simulated body fluid (SBF) at 37 °C in the immersion test with 7-layer chitosan coating whose relative molecular mass is 30×104 Da. The cytotoxicity tests indicate that Mg-6%Zn-10%β-Ca3(PO4)2 with chitosan coating is nontoxic with a cytotoxicity grade of zero against L-929 cells, which is better than that of uncoated composites.

  5. One-Step Method for Preparation of Magnetic Nanoparticles Coated with Chitosan

    Directory of Open Access Journals (Sweden)

    Karla M. Gregorio-Jauregui

    2012-01-01

    Full Text Available Preparation of magnetic nanoparticles coated with chitosan in one step by the coprecipitation method in the presence of different chitosan concentrations is reported here. Obtaining of magnetic superparamagnetic nanoparticles was confirmed by X-ray diffraction and magnetic measurements. Scanning transmission electron microscopy allowed to identify spheroidal nanoparticles with around 10-11 nm in average diameter. Characterization of the products by Fourier transform infrared spectroscopy demonstrated that composite chitosan-magnetic nanoparticles were obtained. Chitosan content in obtained nanocomposites was estimated by thermogravimetric analysis. The nanocomposites were tested in Pb2+ removal from a PbCl2 aqueous solution, showing a removal efficacy up to 53.6%. This work provides a simple method for chitosan-coated nanoparticles obtaining, which could be useful for heavy metal ions removal from water.

  6. Investigations of Self-Healing Property of Chitosan-Reinforced Epoxy Dye Composite Coatings

    Directory of Open Access Journals (Sweden)

    Hüsnügül Yılmaz Atay

    2013-01-01

    Full Text Available Chitosan has a very wide application range in different parts of life such as in biomedical and antimicrobial areas. In recent years the self-healing property of chitosan becomes more of an issue. In the study chitosan was used to obtain a self-healing composite material. An epoxy dye was converted to a self-healing coating. Different types of samples were prepared by coating the glass substrates with a polymer matrix reinforced with various amounts of chitosan. The samples were characterized by fourier transform Infrared (FTIR and scanning electron microscope-energy dispersive spectroscopy (SEM-EDS. In addition, self-healing test was applied as a primary objective of this research. In this respect, the samples were scratched with a very thin pin, and they were analyzed by SEM periodically. It was observed that chitosan-reinforced dyes showed self-healing property. Mechanism of the self-healing process was also scrutinized.

  7. The Effect Of Coating With Chitosan Of Some Degrees Of Concentration On Fruit Quality

    OpenAIRE

    Lince Romauli Panataria; Dharma Bakti; Elisa Julianti

    2015-01-01

    Strawberries are kind of fruit that easily go bad after they are harvested from the orchards. Thus it is needed good post-harvest handlings to retain the fresh quality of the fruits. One of the handlings is coating the fruits with chitosan. It is expected that this coating the fruits with chitosan can prolong the storage of the fruits after they are harvested. This occurs because chitosan can slow down the ripening process of the fruits wheile they are stored. Research has been done to derive...

  8. New Concept of Polymethyl Methacrylate (PMMA and Polyethylene Terephthalate (PET Surface Coating by Chitosan

    Directory of Open Access Journals (Sweden)

    Mieszko Wieckiewicz

    2016-04-01

    Full Text Available Chitosan is known for its hemostatic and antimicrobial properties and might be useful for temporary coating of removable dentures or intraoral splints to control bleeding after oral surgery or as a supportive treatment in denture stomatitis. This study investigated a new method to adhere chitosan to polymethyl methacrylate (PMMA and polyethylene terephthalate (PET. There were 70 cylindrical specimens made from PMMA and 70 from PET (13 mm diameter, 6 mm thickness. The materials with ten specimens each were sandblasted at 2.8 or 4.0 bar with aluminum oxide 110 μm or/and aluminum oxide coated with silica. After sandblasting, all specimens were coated with a 2% or 4% acetic chitosan solution with a thickness of 1 mm. Then the specimens were dried for 120 min at 45 °C. The precipitated chitosan was neutralized with 1 mol NaOH. After neutralization, all specimens underwent abrasion tests using the tooth-brushing simulator with soft brushes (load 2N, 2 cycles/s, 32 °C, 3000 and 30,000 cycles. After each run, the specimen surfaces were analyzed for areas of remaining chitosan by digital planimetry under a light microscope. The best chitosan adhesion was found after sandblasting with aluminum oxide coated with silica (U-Test, p < 0.05 in both the PMMA and the PET groups. Hence, with relatively simple technology, a reliable bond of chitosan to PMMA and PET could be achieved.

  9. Lipid oxidative changes in chitosan-oregano coated traditional dry fermented sausage Petrovská klobása.

    Science.gov (United States)

    Krkić, Nevena; Šojić, Branislav; Lazić, Vera; Petrović, Ljiljana; Mandić, Anamarija; Sedej, Ivana; Tomović, Vladimir

    2013-03-01

    The effect of a chitosan coating with added essential oil of oregano (Origanum vulgare) on lipid oxidation of dry fermented sausage (Petrovská klobása) was investigated. Fatty acid profile, aldehyde contents and sensory analysis of odor and flavor were determined after drying and during seven months of storage. Between coated and control sausage, a difference was observed after two months storage in fatty acid profiles (myristic, oleic and linoleic acids), but after seven months storage there was no difference. Decrease in polyunsaturated acid content was observed (from 17.25% to 15.70%), as well as an increase in total aldehydes (from 4.54 μg/g to 31.80 μg/g), due to lipid oxidation during storage. After seven months storage, the content of most aldehydes was significantly lower in coated sausage than in the control. Sensory characteristics of odor and flavor were better for coated sausage, after seven months of storage. Results suggest that chitosan-oregano coating can be successfully applied to protect dry fermented sausages from lipid oxidation.

  10. Electrophoretic Deposition of Chitosan/h-BN and Chitosan/h-BN/TiO2 Composite Coatings on Stainless Steel (316L Substrates

    Directory of Open Access Journals (Sweden)

    Namir S. Raddaha

    2014-03-01

    Full Text Available This article presents the results of an experimental investigation designed to deposit chitosan/hexagonal boron nitride (h-BN and chitosan/h-BN/titania (TiO2 composites on SS316L substrates using electrophoretic deposition (EPD for potential antibacterial applications. The influence of EPD parameters (voltage and deposition time and relative concentrations of chitosan, h-BN and TiO2 in suspension on deposition yield was studied. The composition and structure of deposited coatings were investigated by FTIR, XRD and SEM. It was observed that h-BN and TiO2 particles were dispersed in the chitosan matrix through simultaneous deposition. The adhesion between the electrophoretic coatings and the stainless steel substrates was tested by using tape test technique, and the results showed that the adhesion strength corresponded to 3B and 4B classes. Corrosion resistance was evaluated by electrochemical polarization curves, indicating enhanced corrosion resistance of the chitosan/h-BN/TiO2 and chitosan/h-BN coatings compared to the bare stainless steel substrate. In order to investigate the in-vitro inorganic bioactivity, coatings were immersed in simulated body fluid (SBF for 28 days. FTIR and XRD results showed no formation of hydroxyapatite on the surface of chitosan/h-BN/TiO2 and chitosan/h-BN coatings, which are therefore non bioactive but potentially useful as antibacterial coatings.

  11. Application of Bioactive Coatings Based on Chitosan for Soybean Seed Protection

    Directory of Open Access Journals (Sweden)

    Defang Zeng

    2012-01-01

    Full Text Available Soybean seeds suffer attacks of various pests that result in a decreased yield in northeastern China. Until recently, people use pesticides such as insecticides to achieve the goal of controlling pests. Chitosan extracted from deacetylation of chitin is promising candidates as a seed-coating agent to control agrotis ypsilon, soybean pod borer, and soybean aphid effectively. An experimental study on influences of chitosan with different concentrations on pest controlling and soybean growth was made in the paper. Coating based on chitosan was used as a feeding deterrent and for enhancing the germination and quality of soybean seeds. Results indicated that all chitosan coating had a significant effect on antifeeding against pests; with the increasing concentration, antifeedant rate (AR were increased obviously, especially when in the concentration of 5%, santifeedant rate of agrotis ypsilon, soybean pod borer, and soybean aphid reached 82.89%, 87.24%, and 80.21%, respectively. Also chitosan coating increased seed germination, plant growth, and soybean yield efficiently, especially when, in the concentration of 5%, the yield was increased by about 20% compared with CK. The application of chitosan in soybean seed coated is an appropriate option to control pests replacing high-toxicity pesticides and enhance soybean yield.

  12. Chitosan microspheres applied for removal of oil from produced water in the oil industry

    Directory of Open Access Journals (Sweden)

    Izabel Cristina da Silva Grem

    2013-01-01

    Full Text Available The discharge of oily wastewaters in the environment is steadily increasing, causing serious damages. Among various treatment methods, adsorption is generally considered the most appropriate, since it can remove both organic and inorganic pollutants. Adsorption using low-cost alternative biopolymers for removal of contaminants from wastewater has been widely investigated. In this context, chitosan has been drawing particular attention because, among its many applications, it can be used in the treatment of aqueous effluents. In this study, microspheres were prepared by reticulation of chitosan with sodium triphosphate (STP and studied for the treatment of water containing crude oil. The microspheres were regular and had surface pores. These microspheres were packed in treatment columns and their ability to remove oil was measured with a fluorometer, by the difference in the oil concentration before and after passing through the column. The microspheres that presented porosity about 80 % were highly efficient in oil removal, with rates above 90%.

  13. Chitosan coated vancomycin hydrochloride liposomes: Characterizations and evaluation.

    Science.gov (United States)

    Yang, Zhenlei; Liu, Junli; Gao, Jinhua; Chen, Shilei; Huang, Guihua

    2015-11-10

    The present work evaluated the feasibility of chitosan coated liposomes (c-Lips) for the intravenous delivery of vancomycin hydrochloride (VANH), a water-soluble antibiotic for the treatment of gram-positive bacterial infections like osteomyelitis, arthritis, endocarditis, pneumonia, etc. The objective of this research was to develop a suitable drug delivery system in vivo which could improve therapeutic efficacy and decrease side effects especially nephrotoxicity. Firstly, the vancomycin hydrochloride liposomes (VANH-Lips) were prepared by modified reverse phase evaporation method, then the chitosan wrapped vancomycin hydrochloride liposomes (c-VANH-Lips) nanosuspension was formulated by the method of electrostatic deposition. Based on the optimized results of single-factor screening experiment, the c-VANH-Lips were found to be relatively uniform in size (220.40 ± 3.56 nm) with a narrow polydispersity index (PI) (0.21 ± 0.03) and a positive zeta potential (25.7 ± 1.12 mV). The average drug entrapment efficiency (EE) and drug loading (DL) were 32.65 ± 0.59% and 2.18 ± 0.04%, respectively. The in vitro release profile of c-VANH-Lips possessed a sustained release Characterization and the release behavior was in accordance with the Weibull equation. Hemolysis experiments showed that its intravenous injection had preliminary safety. In vivo, after intravenous injection to mice, c-VANH-Lips showed a longer retention time and higher AUC values compared with the VANH injection (VANH-Inj) and VANH-Lips. In addition, biodistribution results clearly demonstrated that c-VANH-Lips preferentially decreased the drug distribution in kidney of mice after intravenous injection. These results revealed that injectable c-VANH-Lips may serve as a promising carrier for VANH to increase therapeutic efficacy on gram-positive bacterial infections and reduce nephrotoxicity, which provides significantly clinical value for long-term use of VANH.

  14. Improved postharvest quality in patagonian squash ( Cucurbita moschata) coated with radiation depolymerized chitosan

    Science.gov (United States)

    Pugliese, Maria Alicia; Goitia, Maria Teresa; Yossen, Mariana; Cifone, Norma; Agulló, Enrique; Andreucetti, Noemi

    2011-12-01

    Different molecular weight chitosans were evaluated on the decay of coated Anquito squashes ( Cucurbita moschata) as well as the maintenance of the fruit quality along five storage months. The original chitosan (Mw=391 kDa, 83% DD), was depolymerized by gamma radiation. Apart from chain scission, other chemical changes were not detected by FTIR or UV-vis analyses. The molecular weight characterization of chitosans was done by size exclusion chromatography with dual light scattering and concentration detection (SEC-MALLS-RI). The coating effectiveness was evaluated on the following parameters: fungal decay incidence, weight loss, firmness, total reducing sugar, soluble solid, flesh color, carotene content, pH and titratable acidity. No sign of fungal decay was observed in squashes coated with 122 and 56 kDa chitosans, which were also the most effective treatments in reducing the weight loss. The chitosan with Mw=122 kDa was also the best treatment considering firmness, internal aspect, sugar and carotene content. Then, radiation degraded chitosan was better in C. moschata preservation than the original chitosan.

  15. Sonoelectrochemical Synthesis of PPy-MWCNTs-Chitosan Nanocomposite Coatings: Characterization and Corrosion Behavior

    Science.gov (United States)

    Ashassi-Sorkhabi, Habib; Bagheri, Robabeh; Rezaei-moghadam, Babak

    2015-01-01

    This study investigated the effect of co-incorporation of a kind of nanomaterials and organic additives in a polymer matrix coating on corrosion performance of St-12 steel. We synthesized sonoelectrochemically the polypyrrole (PPy), polypyrrole/chitosan (PPy-chitosan), polypyrrole/multiwalled carbon nanotubes (PPy/MWCNTs), and polypyrrole/MWCNTs/chitosan (PPy-MWCNTs-chitosan) films on the base alloy. In-situ polymerization carried out in a solution containing 0.1 mol/L oxalic acid, 100 mg/L dodecylbenzen sulfonic acid, and 0.1 mol/L pyrrole in the absence and presence of a certain amount of MWCNTs and chitosan. The corrosion protection behavior of the synthesized coatings in 3.5% NaCl aqueous solution was studied by the evolution of the open circuit potential, potentiodynamic polarization, and electrochemical impedance spectroscopy techniques. The results revealed that PPy-MWCNTs-chitosan nanocomposite coating exhibits significantly better corrosion protection than others. The PPy-MWCNTs-chitosan film acts as a physical barrier against the corrosive species, because it has a very dense and more compact structure. The surface morphology was investigated by scanning electron microscopy.

  16. Properties and controlled release of chitosan microencapsulated limonene oil

    Directory of Open Access Journals (Sweden)

    Jefferson M. Souza

    2014-12-01

    Full Text Available Chitosan microcapsules containing limonene essential oil as active ingredient were prepared by coacervation using three different concentrations of NaOH (0.50, 1.00, 1.45 wt% and fixed concentrations of chitosan and surfactant of 0.50 wt%. The produced microcapsules were fully characterized in their morphology and chemical composition, and the kinetic release analysis of the active ingredient was evaluated after deposition in a non-woven cellulose fabric. The concentration of 1.00 and 1.45 wt% clearly show the best results in terms of dimension and shape of the microcapsules as well as in the volatility results. However, at the concentration of 1 wt% a higher number of microcapsules were produced as confirmed by FTIR and EDS analysis. Free microcapsules are spherical in size with disperse diameters between 2 and 12 μm. Immobilized microcapsules showed sizes from 4 to 7 μm, a rough surface and loss of spherical shape with pore formation in the chitosan walls. SEM analysis confirms that at higher NaOH concentrations, the larger the size of the microcapsules. This technique shows that by tuning NaOH concentration it is possible to efficiently control the release rate of encapsulated active agents demonstrating great potential as insect repellent for textiles.

  17. Different preparation methods and characterization of magnetic maghemite coated with chitosan

    Energy Technology Data Exchange (ETDEWEB)

    Hojnik Podrepsek, Gordana; Knez, Zeljko; Leitgeb, Maja, E-mail: maja.leitgeb@um.si [University of Maribor, Laboratory for Separation Processes and Product Design, Faculty of Chemistry and Chemical Engineering (Slovenia)

    2013-06-15

    The preparation of maghemite ({gamma}-Fe{sub 2}O{sub 3}) micro- and nanoparticles coated with chitosan, used as carriers for immobilized enzymes, was investigated. {gamma}-Fe{sub 2}O{sub 3} nanoparticles were synthesized by coprecipitation of Fe{sup 2+} and Fe{sup 3+} ions in the presence of ammonium. They were coated with chitosan by the microemulsion process, suspension cross-linking technique, and covalent binding of chitosan on the {gamma}-Fe{sub 2}O{sub 3} surface. The methods distinguished the concentration of chitosan, concentration of acetic acid solution, concentration of a cross-linking agent, temperature of synthesis, pH of the medium, and time of synthesis. {gamma}-Fe{sub 2}O{sub 3} micro- and nanoparticles coated with chitosan prepared after three preparation methods were evaluated by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy analysis, energy dispersive spectrometry, thermogravimetric analysis, differential scanning calorimetry analysis, vibrating sample magnetometry, dynamic light scattering, laser diffraction granulometry, and X-ray diffractometry. These positive attributes demonstrated that these magnetic micro- and nanoparticles coated with chitosan may be used as a promising carrier for further diverse biomedical applications.

  18. Preparation of Three-Dimensional Chitosan-Graphene Oxide Aerogel for Residue Oil Removal.

    Science.gov (United States)

    Guo, Xiaoqing; Qu, Lijun; Zhu, Shifeng; Tian, Mingwei; Zhang, Xiansheng; Sun, Kaikai; Tang, Xiaoning

    2016-08-01

    Graphene oxide has been used as an adsorbent in wastewater treatment. However, the hydrophily and dispersibility in aqueous solution limit its practical application in environmental protection. In this paper, a novel, environmentally friendly adsorbent, chitosan and chitosan-graphene oxide aerogels with a diverse shape, large specific surface area, and unique porous structure were prepared by a freeze-drying method. The structure of the adsorbents was investigated using scanning electron microscopy, Fourier transform-infrared spectroscopy, and X-ray diffraction (XRD); the specific surface area and swelling capability were also characterized. In addition, removal of diesel oil from seawater by chitosan aerogel (CSAG) and chitosan-graphene oxide aerogel (AGGO-1 and AGGO-2) was studied and batch adsorption experiments were carried out as a function of different adsorbent dosages (0-6 g), contact time (0-120 minutes), pH (3-9), and initial concentrations of oil residue (3-30 g/L) to determine the optimum condition for the adsorption of residue oil from seawater. The results showed that the chitosan-graphene oxide aerogels were more effective to remove diesel oil from seawater compared with pure chitosan aerogel. A removal efficiency ≥ 95% of the chitosan-graphene oxide aerogels could be achieved easily at the initial concentrations of 20 g/L, which indicated that the chitosan-graphene oxide aerogels can be used to treat the industrial oil leakage or effluent in the natural water.

  19. Beeswax-chitosan emulsion coated paper with enhanced water vapor barrier efficiency

    Science.gov (United States)

    Zhang, Weiwei; Xiao, Huining; Qian, Liying

    2014-05-01

    For lipid-hydrocolloid emulsion based film, the increase of lipid amount would improve its water vapor barrier property, but also reduce the mechanical strength of the film in the meantime thus leading to a compromised lipid content in the film. However, when the emulsion is coated on paper surface, more lipid could be used for emulsion preparation to enhance the moisture resistance without considering the weakened strength of the film induced by lipid, because the mechanical properties of emulsion coated paper is mainly governed by the strength of base paper instead of the coating layer. In this study, beeswax-chitosan emulsion was first prepared and then coated on paper surface to improve paper's water vapor barrier and water resistance properties. The range and variance analysis of orthogonal test design showed that the order of priorities of the factors accordingly was beeswax solid content, drying temperature and chitosan concentration. The effect of drying temperature on water vapor transmission rate (WVTR) and water contact angle of coated paper was further investigated using 1.2 wt% chitosan and 96% beeswax solid content in the coating layer. The results indicated that water vapor barrier property was in accordance with the density of the coating layer. Atomic force microscope (AFM) was also used to characterize the surface morphology and explain the hydrophobicity of beeswax-chitosan coated paper. It was found that surface beeswax particles melted to wrinkle at high drying temperatures, while roughness values maintained at micro-scale over the temperature range investigated.

  20. Inactivation of Salmonella on tomato stem scars by edible chitosan and organic acid coatings

    Science.gov (United States)

    This study investigated the efficacy of antimicrobial coatings on inactivation of Salmonella on the surface of tomato stem scars, which was inoculated with a four-strain cocktail of Salmonella (S. Montevideo. S. Newport. S. Saintpaul, and S. Typhimurium) and coated with acid-chitosan solutions. The ...

  1. Oleic acid-grafted chitosan/graphene oxide composite coating for corrosion protection of carbon steel.

    Science.gov (United States)

    Fayyad, Eman M; Sadasivuni, Kishor Kumar; Ponnamma, Deepalekshmi; Al-Maadeed, Mariam Al Ali

    2016-10-20

    An anticorrosion coating film based on the formation of nanocomposite coating is reported in this study. The composite consisted of chitosan (green matrix), oleic acid, and graphene oxide (nano filler). The nanocomposite coating was arranged on the surface of carbon steel, and the corrosion resistance was monitored using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PP). Compared to the pure chitosan (CS) coating, the corrosion resistance of oleic acid-modified chitosan/graphene oxide film (CS/GO-OA) is increased by 100 folds. Since the well-dispersed smart grafted nanolayers delayed the penetration rate of corrosive species and thus maintained long term anticorrosive stability which is correlated with hydrophobicity and permeability.

  2. Beeswax–chitosan emulsion coated paper with enhanced water vapor barrier efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Weiwei [Department of Chemical Engineering, University of New Brunswick, 15 Dineen Drive, Fredericton, NB E3B 5A3 (Canada); State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, Guangdong 510640 (China); Xiao, Huining, E-mail: hxiao@unb.ca [Department of Chemical Engineering, University of New Brunswick, 15 Dineen Drive, Fredericton, NB E3B 5A3 (Canada); Qian, Liying [State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, Guangdong 510640 (China)

    2014-05-01

    Graphical abstract: - Highlights: • The water vapor barrier efficiency of paper was enhanced via green-based emulsion coating. • Extremely high lipid content in the emulsion coating layer was firstly utilized to reduce WVTR in emulsion-based film. • A controlled WVTR of beeswax–chitosan emulsion coating could be obtained by dying at specific temperature. - Abstract: For lipid–hydrocolloid emulsion based film, the increase of lipid amount would improve its water vapor barrier property, but also reduce the mechanical strength of the film in the meantime thus leading to a compromised lipid content in the film. However, when the emulsion is coated on paper surface, more lipid could be used for emulsion preparation to enhance the moisture resistance without considering the weakened strength of the film induced by lipid, because the mechanical properties of emulsion coated paper is mainly governed by the strength of base paper instead of the coating layer. In this study, beeswax–chitosan emulsion was first prepared and then coated on paper surface to improve paper's water vapor barrier and water resistance properties. The range and variance analysis of orthogonal test design showed that the order of priorities of the factors accordingly was beeswax solid content, drying temperature and chitosan concentration. The effect of drying temperature on water vapor transmission rate (WVTR) and water contact angle of coated paper was further investigated using 1.2 wt% chitosan and 96% beeswax solid content in the coating layer. The results indicated that water vapor barrier property was in accordance with the density of the coating layer. Atomic force microscope (AFM) was also used to characterize the surface morphology and explain the hydrophobicity of beeswax–chitosan coated paper. It was found that surface beeswax particles melted to wrinkle at high drying temperatures, while roughness values maintained at micro-scale over the temperature range investigated.

  3. Effect of the Fish Oil Fortified Chitosan Edible Film on Microbiological, Chemical Composition and Sensory Properties of Göbek Kashar Cheese during Ripening Time.

    Science.gov (United States)

    Yangilar, Filiz

    2016-01-01

    Objective of the present study is to investigate the effect of coated edible films with chitosan solutions enriched with essential oil (EO) on the chemical, microbial and sensory properties of Kashar cheese during ripening time. Generally, no differences were found in total aerobic mesophilic bacteria, streptococci and lactoccocci counts among cheeses but these microorganism counts increased during 60 and 90 d storage especially in C1 (uncoated sample) as compared with coated samples. Antimicrobial effectiveness of the films against moulds was measured on 30, 60, and 90 d of storage. In addition of fish EO into chitosan edible films samples were showed to affect significantly decreased the moulds (poil (1% w/v) fortified chitosan film) on the 90(th) d, while in C1 as 3.89 Log CFU/g on the 90(th) d of ripening. Compared to other cheese samples, C2 (coated with chitosan film) and C4 coated cheese samples revealed higher levels of water-soluble nitrogen and ripening index at the end of storage. C2 coated cheese samples were preferred more by the panellists while C4 coated cheese samples received the lowest scores.

  4. 丁香油、百里酚复合壳聚糖处理对桃采后褐腐病菌的抑制作用%Antibacterial effects of combined chitosan of eugenia oil and thymol coating on Monilinia fructicola in harvested peach

    Institute of Scientific and Technical Information of China (English)

    王京法; 李健; 曹建康; 姜微波

    2011-01-01

    为了进一步提高壳聚糖用于涂膜时的综合抗菌能力,采用滤纸片法及菌丝扩展法测定并对比了丁香油和百里酚对桃采后致病褐腐菌的抗菌能力及用微孔板法测定了它们的最小抑菌浓度,并将丁香油、百里酚复合壳聚糖对桃果进行涂膜,测量果体经过涂膜和接菌后的病斑扩展.结果表明丁香油和百里酚都具有较好的抗褐腐菌能力,百里酚强于丁香油,复合壳聚糖涂膜时二者都可以提高壳聚糖总体抗菌能力且复合百里酚效果较好.二者具有作为壳聚糖涂膜保鲜添加剂的应用潜力.%In order to increase the total antibacterial capacity of chitosan coating on the fruits, the antibacterial effects of coating- treated peach fruit by eugenia oil, thymol and the eugenia- thymol combination were comparaed.The effects were evaluated by the extent of the pathological spot changes and minimum antibacterial concentrations.The test results showed that the eugenia and thymol all had better anti-rnonilining fructicola effect and the thymol had better effect than eugenia oil.Moreover, the effect of combination of eugenia and thymol was better than the single ones.The eugenia and thymol both had the application potential for the fruit preservation coating.

  5. Preparation of Chitosan-coated Nylon Membranes and their Application as Affinity Membranes

    Institute of Scientific and Technical Information of China (English)

    Wei SHI; Feng Bao ZHANG; Guo Liang ZHANG

    2005-01-01

    Chitosan-coated nylon membranes which possess a large number of reactive groups of-CH2OH and -NH2 were prepared by coupling chitosan onto the nylon membrane. Then polylysine as ligand was also immobilized onto the composite membranes by 1, l′-carbonyldiimidazole activation to prepare affinity membranes for bilirubin adsorption. The results showed that these membranes exhibited high binding affinity capacities for bilirubin and the adsorption isotherm fitted the Freundlich model well.

  6. Improvement of antioxidant and antimicrobial activity of chitosan film with caraway and oregano essential oils

    Directory of Open Access Journals (Sweden)

    Hromiš Nevena M.

    2014-01-01

    Full Text Available In this work, caraway or oregano essential oils were added to the cast chitosan film in an attempt to design a natural, biodegradable, bioactive (antioxidant and antimicrobial packaging film. When the structure of the tested films was analyzed with Fourier transform infrared spectroscopy, no significant differences were found between the chitosan film with and without essential oils of caraway or oregano. The lowest antioxidant activity, based on the scavenging of the stable DPPH• free radical, was detected for the chitosan film without oil addition, going from 11.64%, after 2.5 h to 28.96%, after 24 h. When the caraway essential oil was added to the chitosan film, the antioxidant activity was increased (p<0.05 to 33.47±4.77%, after 2.5 h and to 81.08±0.64%, after 24 h. This increase in the antioxidant activity was even higher in the film with oregano essential oil (p<0.05. After 2.5 h, the value for the antioxidant activity of the chitosan-oregano film was 87.58±1.71%, and after 4 h and 24 h it was above 90%. The obtained results for the antimicrobial activity showed that the chitosan film is an effective antimicrobial agent against Escherichia coli and Staphylococcus aureus. When caraway essential oil was added in 1% volume concentration to the film, no increase in the antimicrobial action of chitosan film was detected. On the other hand, the addition of oregano essential oil promoted chitosan film antimicrobial activity, which was particularly evident with Escherichia coli. The results showed that the chitosan film can be successfully applied as a matrix carrier for essential oils in the active film system.[ Projekat Ministarstva nauke Republike Srbije, br. TR31032

  7. Chitosan/Kollicoat SR 30D film-coated pellets of aminosalicylates for colonic drug delivery.

    Science.gov (United States)

    Wei, He; Li-Fang, Fan; Min, Bai; Yong-Zhen, Chang; Bai, Xiang; Qing, Du; Feng, Wang; Min, Qin; De-Ying, Cao

    2010-01-01

    The purpose of the study was to (i) prepare the chitosan/Kollicoat SR 30D film-coated pellets for colonic drug delivery, and (ii) evaluate the colonic delivery and efficacy of these coated pellets in the rat. The pellets were coated to different film thickness with chitosan/Kollicoat SR 30D formulations. In vitro drug release was assessed in simulated gastrointestinal (GI) tract conditions. Biodistribution of aminosalicylates (5-ASA) in GI tract and plasma was measured after oral administration of coated or uncoated 5-ASA pellets. Efficacy of the coated or uncoated 5-ASA pellets was tested in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced rat colitis model. Healing of induced colitis was assessed by measuring the myeloperoxidase activities, colon wet weight/body weight, and damage score. The coating was susceptible to bacteria digestion, resulting in an increase in the release of 5-ASA from the coated pellets. After administration of the coated pellets, the drug concentration in the large intestine was higher than those of uncoated pellets. In plasma, the observed mean C(max) from the coated pellets was significantly lower than that of the uncoated pellets. Chitosan/Kollicoat SR 30D film-coated pellets could deliver the 5-ASA to the targeted site, providing effective treatment for inflammatory bowel disease.

  8. Properties of chitosan microencapsulated orange oil prepared by spray-drying and its stability to detergents

    Science.gov (United States)

    Fragrance encapsulated in small particles of less than 20 µm diameter is preferred for use in textiles. In this study, aromatic orange oil was emulsified in a continuous phase of chitosan and spray-dried to produce microcapsules. The most effective combination of emulsifiers, ratio of chitosan to oi...

  9. Antimicrobial Active Packaging including Chitosan Films with Thymus vulgaris L. Essential Oil for Ready-to-Eat Meat

    Directory of Open Access Journals (Sweden)

    Jesús Quesada

    2016-08-01

    Full Text Available An active packaging system has been designed for the shelf life extension of ready to eat meat products. The package included an inner surface coated with a chitosan film with thyme essential oil (0%, 0.5%, 1%, and 2% not in direct contact with the meat. Our aim was to reduce the impact of thyme essential oil (EO on meat sensory properties by using a chemotype with low odor intensity. The pH, color parameters, microbial populations, and sensory properties were assessed during 4 weeks of refrigerated storage. The presence of EO films reduced yeast populations, whereas aerobic mesophilic bacteria, lactic acid bacteria, and enterobacteria were not affected by the presence of the EO in the films. Meat color preservation (a * was enhanced in the presence of EO, giving a better appearance to the packaged meat. The presence of the chitosan-EO layer reduced water condensation inside the package, whereas packages containing only chitosan had evident water droplets. Thyme odor was perceived as desirable in cooked meat, and the typical product odor intensity decreased by increasing the EO concentration. Further studies should point towards developing oil blends or combinations with natural antimicrobial agents to be incorporated into the film to improve its antimicrobial properties.

  10. Antimicrobial Active Packaging including Chitosan Films with Thymus vulgaris L. Essential Oil for Ready-to-Eat Meat

    Science.gov (United States)

    Quesada, Jesús; Sendra, Esther; Navarro, Casilda; Sayas-Barberá, Estrella

    2016-01-01

    An active packaging system has been designed for the shelf life extension of ready to eat meat products. The package included an inner surface coated with a chitosan film with thyme essential oil (0%, 0.5%, 1%, and 2%) not in direct contact with the meat. Our aim was to reduce the impact of thyme essential oil (EO) on meat sensory properties by using a chemotype with low odor intensity. The pH, color parameters, microbial populations, and sensory properties were assessed during 4 weeks of refrigerated storage. The presence of EO films reduced yeast populations, whereas aerobic mesophilic bacteria, lactic acid bacteria, and enterobacteria were not affected by the presence of the EO in the films. Meat color preservation (a *) was enhanced in the presence of EO, giving a better appearance to the packaged meat. The presence of the chitosan-EO layer reduced water condensation inside the package, whereas packages containing only chitosan had evident water droplets. Thyme odor was perceived as desirable in cooked meat, and the typical product odor intensity decreased by increasing the EO concentration. Further studies should point towards developing oil blends or combinations with natural antimicrobial agents to be incorporated into the film to improve its antimicrobial properties. PMID:28231152

  11. Antimicrobial Active Packaging including Chitosan Films with Thymus vulgaris L. Essential Oil for Ready-to-Eat Meat.

    Science.gov (United States)

    Quesada, Jesús; Sendra, Esther; Navarro, Casilda; Sayas-Barberá, Estrella

    2016-08-29

    An active packaging system has been designed for the shelf life extension of ready to eat meat products. The package included an inner surface coated with a chitosan film with thyme essential oil (0%, 0.5%, 1%, and 2%) not in direct contact with the meat. Our aim was to reduce the impact of thyme essential oil (EO) on meat sensory properties by using a chemotype with low odor intensity. The pH, color parameters, microbial populations, and sensory properties were assessed during 4 weeks of refrigerated storage. The presence of EO films reduced yeast populations, whereas aerobic mesophilic bacteria, lactic acid bacteria, and enterobacteria were not affected by the presence of the EO in the films. Meat color preservation (a *) was enhanced in the presence of EO, giving a better appearance to the packaged meat. The presence of the chitosan-EO layer reduced water condensation inside the package, whereas packages containing only chitosan had evident water droplets. Thyme odor was perceived as desirable in cooked meat, and the typical product odor intensity decreased by increasing the EO concentration. Further studies should point towards developing oil blends or combinations with natural antimicrobial agents to be incorporated into the film to improve its antimicrobial properties.

  12. A construction of novel iron-foam-based calcium phosphate/chitosan coating biodegradable scaffold material.

    Science.gov (United States)

    Wen, Zhaohui; Zhang, Liming; Chen, Chao; Liu, Yibo; Wu, Changjun; Dai, Changsong

    2013-04-01

    Slow corrosion rate and poor bioactivity restrict iron-based implants in biomedical application. In this study, we design a new iron-foam-based calcium phosphate/chitosan coating biodegradable composites offering a priority mechanical and bioactive property for bone tissue engineering through electrophoretic deposition (EPD) followed by a conversion process into a phosphate buffer solution (PBS). Tensile test results showed that the mechanical property of iron foam could be regulated through altering the construction of polyurethane foam. The priority coatings were deposited from 40% nano hydroxyapatite (nHA)/ethanol suspension mixed with 60% nHA/chitosan-acetic acid aqueous solution. In vitro immersion test showed that oxidation-iron foam as the matrix decreased the amount of iron implanted and had not influence on the bioactivity of this implant, obviously. So, this method could also be a promising method for the preparation of a new calcium phosphate/chitosan coating on foam construction.

  13. Physical and Oxidative Stability of Uncoated and Chitosan-Coated Liposomes Containing Grape Seed Extract

    Directory of Open Access Journals (Sweden)

    Jochen Weiss

    2013-08-01

    Full Text Available Polyphenol-rich grape seed extract (0.1 w/w% was incorporated in liposomes (1 w/w% soy lecithin by high pressure homogenization (22,500 psi and coated with chitosan (0.1 w/w%. Primary liposomes and chitosan-coated secondary liposomes containing grape seed extract showed good physical stability during 98 days of storage. Most of the polyphenols were incorporated in the shell of the liposomes (85.4%, whereas only 7.6% of the polyphenols of grape seed extract were located in the interior of the liposomes. Coating with chitosan did not change the polyphenol content in the liposomes (86.6%. The uncoated liposomes without grape seed extract were highly prone to lipid oxidation. The cationic chitosan coating, however, improved the oxidative stability to some extent, due to its ability to repel pro-oxidant metals. Encapsulated grape seed extract showed high antioxidant activity in both primary and secondary liposomes, which may be attributed to its polyphenol content. In conclusion, the best chemical stability of liposomes can be achieved using a combination of grape seed extract and chitosan.

  14. Physical and oxidative stability of uncoated and chitosan-coated liposomes containing grape seed extract.

    Science.gov (United States)

    Gibis, Monika; Rahn, Nina; Weiss, Jochen

    2013-08-20

    Polyphenol-rich grape seed extract (0.1 w/w%) was incorporated in liposomes (1 w/w% soy lecithin) by high pressure homogenization (22,500 psi) and coated with chitosan (0.1 w/w%). Primary liposomes and chitosan-coated secondary liposomes containing grape seed extract showed good physical stability during 98 days of storage. Most of the polyphenols were incorporated in the shell of the liposomes (85.4%), whereas only 7.6% of the polyphenols of grape seed extract were located in the interior of the liposomes. Coating with chitosan did not change the polyphenol content in the liposomes (86.6%). The uncoated liposomes without grape seed extract were highly prone to lipid oxidation. The cationic chitosan coating, however, improved the oxidative stability to some extent, due to its ability to repel pro-oxidant metals. Encapsulated grape seed extract showed high antioxidant activity in both primary and secondary liposomes, which may be attributed to its polyphenol content. In conclusion, the best chemical stability of liposomes can be achieved using a combination of grape seed extract and chitosan.

  15. PEGylated chitosan protected silver nanoparticles as water-borne coating for leather with antibacterial property.

    Science.gov (United States)

    Liu, Gongyan; Li, Kaijun; Luo, Quanqing; Wang, Haibo; Zhang, Zongcai

    2017-03-15

    Development of eco-labeled and effectively antibacterial coatings for final leather products has been desiderated both by industry and by consumers. Herein, PEGylated chitosan modified silver nanoparticles (PEG-g-CS@AgNPs) were prepared and characterized by UV-vis spectroscopy, transmission electron microscopy and dynamic light scattering. The antimicrobial activity of such silver nanoparticles was investigated against Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus), exhibiting much lower minimum inhibitory concentration (MIC) than chitosan or PEG-g-CS. Water-borne coating was formed by immobilizing the PEG-g-CS@AgNPs onto the leather surface through the electrostatic interaction between amino groups of chitosan and carboxyl groups of leather collagen. Scanning electron microscopy and water contact angle were employed to study the coating's morphology and hydrophilicity, respectively. After coating, leather samples showed significantly high bactericidal efficiency with reusability after release of dead cells from the coating by simply water washing. The excellent antibacterial property of PEG-g-CS@AgNPs coating was ascribed to the combination of bacteria-resistance and bacteria-release by PEGylation, and dual bacteria-killing based on chitosan and Ag(+) release.

  16. Insights into and relative effect of chitosan-krill oil, chitosan-H-aspirin, chitosan-H-krill oil-nystatin and chitosan-H-krill oil-aspirin-nystatin on dentin bond strength and functional drug delivery capacity: In-vitro studies

    Directory of Open Access Journals (Sweden)

    Victoria Tamara Perchyonok

    2014-01-01

    Full Text Available Background: Restorative materials in the new era aim to be "bio-active" and long-lasting. The purpose of this study was to design and to evaluate a novel chitosan hydrogels containing krill oil (antioxidant containing material, nystatin (antifungal, aspirin (pain relieve medication and free radical scavengers and combinations thereof (chitosan-H-krill oil, chitosan-H-krill oil-nystatin and chitosan-H-aspirin, chitosan-H-aspirin-nystatin, chitosan-H-krill oil-aspirin and chitosan-H-krill oil-aspirin-nystatin as functional additive prototypes for further development of "dual function restorative materials," and secondly to determine their effect on the dentin bond strength of a composite. Materials and Methods: The above-mentioned hydrogels were prepared by dispersion the corresponding component in glycerol and acetic acid with the addition of chitosan gelling agent. The surface morphology (scanning electron microscope (SEM, release behaviors (physiological pH and also in acidic conditions, stability of the therapeutic agent-antioxidant-chitosan and the effect of the hydrogels on the shear bond strength of dentin were also evaluated. Results: The release of nystatin and aspirin confer the added benefit of synergistic action of a functional therapeutic delivery when comparing the newly designed chitosan-based hydrogel restorative materials to the commercially available products alone. Neither the release of nystatin and aspirin nor the antioxidant stability was affected by storage over a 6 month period. The hydrogel formulations have a uniform distribution of drug content, homogenous texture and yellow color (SEM study. All chitosan dentin treated hydrogels gave significantly (P<0.05; non-parametric ANOVA test higher shear bond values (P<0.05 than dentin treated or not treated with phosphoric acid. Conclusion: The added benefits of the chitosan treated hydrogels involved positive influence on the nystatin and aspirin release as well as increased

  17. Control of Listeria monocytogenes on cold-smoked salmon using chitosan-based antimicrobial coatings and films.

    Science.gov (United States)

    Jiang, Zheng; Neetoo, Hudaa; Chen, Haiqiang

    2011-01-01

    The relatively high incidence of Listeria monocytogenes in ready-to-eat (RTE) products such as cold-smoked salmon is of serious concern. The objective of this study was to evaluate the efficacy of chitosan-based edible coatings and films incorporating 3 generally recognized as safe (GRAS) antimicrobials, sodium lactate (SL), sodium diacetate (SD), and potassium sorbate (PS), against L. monocytogenes on cold-smoked salmon. Salmon samples were surface-inoculated with a 5-strain cocktail of Listeria monocytogenes to a final concentration of 4.4 log CFU/cm(2) and then either coated with chitosan solutions or wrapped with chitosan films with or without the 3 antimicrobials. The samples were then vacuum packaged and stored at 4 °C for 30 d. The chitosan coatings with or without the antimicrobials consistently showed higher efficacy against L. monocytogenes than chitosan films having the same compositions. The most effective film treatments, chitosan films containing 1.2% SL/0.25% SD or 2.4% SL, achieved ≥ 1.3 log reductions of L. monocytogenes during the 30 d of refrigerated storage, while the most effective coating treatments, chitosan coatings containing 1.2% SL/0.25% SD or 0.15% PS/0.125% SD, achieved ≥ 2.8 log reductions. Practical Application: This study shows that chitosan-based edible coatings and films hold promise and can potentially assist fishery industries in their efforts to control L. monocytogenes.

  18. Biocompatibility of chitosan-coated iron oxide nanoparticles with osteoblast cells

    Directory of Open Access Journals (Sweden)

    Shi S

    2012-10-01

    Full Text Available Si-Feng Shi,1 Jing-Fu Jia,2 Xiao-Kui Guo,3 Ya-Ping Zhao,2 De-Sheng Chen,1 Yong-Yuan Guo,1 Tao Cheng,1 Xian-Long Zhang11Department of Orthopedic Surgery, Shanghai Sixth People’s Hospital, School of Medicine, 2School of Chemistry and Chemical Technology, 3Department of Medical Microbiology and Parasitology, School of Medicine, Shanghai Jiao Tong University Shanghai, ChinaBackground: Bone disorders (including osteoporosis, loosening of a prosthesis, and bone infections are of great concern to the medical community and are difficult to cure. Therapies are available to treat such diseases, but all have drawbacks and are not specifically targeted to the site of disease. Chitosan is widely used in the biomedical community, including for orthopedic applications. The aim of the present study was to coat chitosan onto iron oxide nanoparticles and to determine its effect on the proliferation and differentiation of osteoblasts.Methods: Nanoparticles were characterized using transmission electron microscopy, dynamic light scattering, x-ray diffraction, zeta potential, and vibrating sample magnetometry. Uptake of nanoparticles by osteoblasts was studied by transmission electron microscopy and Prussian blue staining. Viability and proliferation of osteoblasts were measured in the presence of uncoated iron oxide magnetic nanoparticles or those coated with chitosan. Lactate dehydrogenase, alkaline phosphatase, total protein synthesis, and extracellular calcium deposition was studied in the presence of the nanoparticles.Results: Chitosan-coated iron oxide nanoparticles enhanced osteoblast proliferation, decreased cell membrane damage, and promoted cell differentiation, as indicated by an increase in alkaline phosphatase and extracellular calcium deposition. Chitosan-coated iron oxide nanoparticles showed good compatibility with osteoblasts.Conclusion: Further research is necessary to optimize magnetic nanoparticles for the treatment of bone disease

  19. Determination of tackiness of chitosan film-coated pellets exploiting minimum fluidization velocity.

    Science.gov (United States)

    Fernández Cervera, M; Heinämäki, J; Räsänen, E; Antikainen, O; Nieto, O M; Iraizoz Colarte, A; Yliruusi, J

    2004-08-20

    The tackiness of aqueous chitosan film coatings and effects of anti-sticking agents on sticking tendency, were evaluated. A novel rapid method exploiting minimum fluidization velocity to determine tackiness was introduced and tested. The pressure difference over the miniaturized fluidized-bed was precisely recorded as a function of velocity of fluidization air. High molecular weight chitosan plasticized with glycerol was used as a film-forming agent. Magnesium stearate, titanium dioxide, colloidal silicon dioxide and glyceryl-1-monostearate (GMS) were studied as anti-sticking agents. Film coatings were performed in a miniaturized top-spray coater. The incorporation of anti-sticking agents led to a clear decrease in tackiness of the chitosan films, and magnesium stearate and GMS were shown the most effective. Film-coated pellets containing magnesium stearate and GMS as an anti-sticking agent were very easily fluidized (showing very low values of minimum fluidization velocity) and were thus classified as the best flowing and the least sticking samples. Both these additives were found anti-sticking agents of choice for aqueous chitosan film coatings. Determination of the experimental minimum fluidization velocity in a fluidized bed, is a useful and sensitive method of measuring the tackiness tendency of film-coated pellets.

  20. A bioactive coating of a silica xerogel/chitosan hybrid on titanium by a room temperature sol-gel process.

    Science.gov (United States)

    Jun, Shin-Hee; Lee, Eun-Jung; Yook, Se-Won; Kim, Hyoun-Ee; Kim, Hae-Won; Koh, Young-Hag

    2010-01-01

    A bioactive coating consisting of a silica xerogel/chitosan hybrid was applied to Ti at room temperature as a novel surface treatment for metallic implants. A crack-free thin layer (coated on Ti with a chitosan content of >30 vol.% through a sol-gel process. The coating layer became more hydrophilic with increasing silica xerogel content, as assessed by contact angle measurement. The hybrid coatings afforded excellent bone bioactivity by inducing the rapid precipitation of apatite on their surface when immersed in a simulated body fluid (SBF). Osteoblastic cells cultured on the hybrid coatings were more viable than those on a pure chitosan coating. Furthermore, the alkaline phosphate activity of the cells was significantly higher on the hybrid coatings than on a pure chitosan coating, with the highest level being achieved on the hybrid coating containing 30% chitosan. These results indicate that silica xerogel/chitosan hybrids are potentially useful as room temperature bioactive coating materials on titanium-based medical implants.

  1. Adsorption and photocatalyst assisted dye removal and bactericidal performance of ZnO/chitosan coating layer.

    Science.gov (United States)

    Kamal, Tahseen; Ul-Islam, Mazhar; Khan, Sher Bahadar; Asiri, Abdullah M

    2015-11-01

    Pure chitosan and its zinc oxide composite coatings were applied on microfibriller cellulose mat (MCM) to prepare chitosan coated microfibriller cellulose (Chi-MCM) and zinc oxide/chitosan coated microfibriller cellulose (ZnO/Chi-MCM), respectively. X-ray diffraction (XRD), and scanning electron microscopy (SEM), were used to characterize the samples in this study. SEM images showed that dense chitosan solutions (3 and 5wt%) made a thick layer over MCM while diluted solution (1wt%) resulted in wrapping of the chitosan over the individual microfibers and avoided the thick layer formation. Removal of an azo dye methyl orange (MO) from aqueous solution using adsorption and combined adsorption with photodegradation activity of the Chi-MCM and ZnO/Chi-MCM were evaluated, respectively. Compared in the absence of UV light, ZnO/Chi-MCM showed faster and higher degree of dye removal by photocatalytic dissociation and adsorption under ultraviolet irradiation. Various parameters including pH of MO solution and its initial concentration were tested for the removal of MO dye. ZnO/Chi-MCM showed maximum adsorption capacity of 42.8mg/g. Antibacterial activities were also evaluated where ZnO/Chi-MCM displayed a remarkable performance inhibiting the Escherichia coli growth.

  2. Chitosan-Iron Oxide Coated Graphene Oxide Nanocomposite Hydrogel: A Robust and Soft Antimicrobial Biofilm.

    Science.gov (United States)

    Konwar, Achyut; Kalita, Sanjeeb; Kotoky, Jibon; Chowdhury, Devasish

    2016-08-17

    We report a robust biofilm with antimicrobial properties fabricated from chitosan-iron oxide coated graphene oxide nanocomposite hydrogel. For the first time, the coprecipitation method was used for the successful synthesis of iron oxide coated graphene oxide (GIO) nanomaterial. After this, films were fabricated by the gel-casting technique aided by the self-healing ability of the chitosan hydrogel network system. Both the nanomaterial and the nanocomposite films were characterized by techniques such as scanning electron microscopy, FT-IR spectroscopy, X-ray diffraction, and vibrating sample magnetometry. Measurements of the thermodynamic stability and mechanical properties of the films indictaed a significant improvement in their thermal and mechanical properties. Moreover, the stress-strain profile indicated the tough nature of the nanocomposite hydrogel films. These improvements, therefore, indicated an effective interaction and good compatibility of the GIO nanomaterial with the chitosan hydrogel matrix. In addition, it was also possible to fabricate films with tunable surface properties such as hydrophobicity simply by varying the loading percentage of GIO nanomaterial in the hydrogel matrix. Fascinatingly, the chitosan-iron oxide coated graphene oxide nanocomposite hydrogel films displayed significant antimicrobial activities against both Gram-positive and Gram-negative bacterial strains, such as methicillin-resistant Staphylococcus aureus, Staphylococcus aureus, and Escherichia coli, and also against the opportunistic dermatophyte Candida albicans. The antimicrobial activities of the films were tested by agar diffusion assay and antimicrobial testing based on direct contact. A comparison of the antimicrobial activity of the chitosan-GIO nanocomposite hydrogel films with those of individual chitosan-graphene oxide and chitosan-iron oxide nanocomposite films demonstrated a higher antimicrobial activity for the former in both types of tests. In vitro hemolysis

  3. Chitosan/silica coated carbon nanotubes composite proton exchange membranes for fuel cell applications.

    Science.gov (United States)

    Liu, Hai; Gong, Chunli; Wang, Jie; Liu, Xiaoyan; Liu, Huanli; Cheng, Fan; Wang, Guangjin; Zheng, Genwen; Qin, Caiqin; Wen, Sheng

    2016-01-20

    Silica-coated carbon nanotubes (SCNTs), which were obtained by a simple sol-gel method, were utilized in preparation of chitosan/SCNTs (CS/SCNTs) composite membranes. The thermal and oxidative stability, morphology, mechanical properties, water uptake and proton conductivity of CS/SCNTs composite membranes were investigated. The insulated and hydrophilic silica layer coated on CNTs eliminates the risk of electronic short-circuiting and enhances the interaction between SCNTs and chitosan to ensure the homogenous dispersion of SCNTs, although the water uptake of CS/SCNTs membranes is reduced owing to the decrease of the effective number of the amino functional groups of chitosan. The CS/SCNTs composite membranes are superior to the pure CS membrane in thermal and oxidative stability, mechanical properties and proton conductivity. The results of this study suggest that CS/SCNTs composite membranes exhibit promising potential for practical application in proton exchange membranes.

  4. Post-harvest conservation of organic strawberries coated with cassava starch and chitosan

    Directory of Open Access Journals (Sweden)

    Raquel P Campos

    2011-10-01

    Full Text Available The strawberry is as non-climacteric fruit, but has a high post-harvest respiration rate, which leads to a rapid deterioration at room temperature. This study aimed to evaluate the application of biodegradable coating on postharvest conservation of organic strawberries, cv. Camarosa, packed in plastic hinged boxes and stored at 10ºC. The treatments consisted of: a control; b 2% cassava starch; c 1% chitosan; and d 2% cassava starch + 1% chitosan. Physical and chemical characteristics of fruits were evaluated at 3, 6 and 9 days of storage, and microbiological and sensory analyses were carried out at the end of the storage period. The treatments influenced positively the post-harvest quality of organic strawberries. The coating cassava starch + chitosan provided the best results, with less than 6% of loss in fruit mass, lower counts of yeast and psychrophilic microorganisms and the best appearance according to the sensory analysis.

  5. Reduced Staphylococcus aureus biofilm formation in the presence of chitosan-coated iron oxide nanoparticles.

    Science.gov (United States)

    Shi, Si-Feng; Jia, Jing-Fu; Guo, Xiao-Kui; Zhao, Ya-Ping; Chen, De-Sheng; Guo, Yong-Yuan; Zhang, Xian-Long

    Staphylococcus aureus can adhere to most foreign materials and form biofilm on the surface of medical devices. Biofilm infections are difficult to resolve. The goal of this in vitro study was to explore the use of chitosan-coated nanoparticles to prevent biofilm formation. For this purpose, S. aureus was seeded in 96-well plates to incubate with chitosan-coated iron oxide nanoparticles in order to study the efficiency of biofilm formation inhibition. The biofilm bacteria count was determined using the spread plate method; biomass formation was measured using the crystal violet staining method. Confocal laser scanning microscopy and scanning electron microscopy were used to study the biofilm formation. The results showed decreased viable bacteria numbers and biomass formation when incubated with chitosan-coated iron oxide nanoparticles at all test concentrations. Confocal laser scanning microscopy showed increased dead bacteria and thinner biofilm when incubated with nanoparticles at a concentration of 500 µg/mL. Scanning electron microscopy revealed that chitosan-coated iron oxide nanoparticles inhibited biofilm formation in polystyrene plates. Future studies should be performed to study these nanoparticles for anti-infective use.

  6. Effects of Lactobacillus plantarum immobilization in alginate coated with chitosan and gelatin on antibacterial activity.

    Science.gov (United States)

    Trabelsi, Imen; Ayadi, Dorra; Bejar, Wacim; Bejar, Samir; Chouayekh, Hichem; Ben Salah, Riadh

    2014-03-01

    The present study aimed to investigate and evaluate the efficiency of immobilizing the Lactobacillus plantarum TN9 strain in alginate using chitosan and gelatin as coating materials, in terms of viability and antibacterial activity. The results indicate that maximum concentrations of L. plantarum TN9 strain were produced with 2% sodium alginate, 10(8)UFC/ml, and 1M calcium chloride. The viability and antibacterial activity of the L. plantarum TN9 cultures before and after immobilization in alginate, chitosan-coated alginate, and gelatin-coated alginate, were studied. The findings revealed that the viability of encapsulated L. plantarum could be preserved more than 5.8 log CFU/ml after 35 day of incubation at 4 °C, and no effects were observed when gelatin was used. The antibacterial activity of encapsulated L. plantarum TN9 against Gram-positive and Gram-negative pathogenic bacteria was enhanced in the presence of chitosan coating materials, and no activity was observed in the presence of gelatin. The effects of catalase and proteolytic enzymes on the culture supernatant of L. plantarum TN9 were also investigated, and the results suggested that the antibacterial activity observed was due to the production of organic acids. Taken together, the findings indicated that immobilization in chitosan enhanced the antibacterial activity of L. plantarum TN9 against several pathogenic bacteria. This encapsulated strain could be considered as a potential strong candidate for future application as an additive in the food and animal feed industries.

  7. Chitosan-coated nickel-ferrite nanoparticles as contrast agents in magnetic resonance imaging

    Science.gov (United States)

    Ahmad, Tanveer; Bae, Hongsub; Iqbal, Yousaf; Rhee, Ilsu; Hong, Sungwook; Chang, Yongmin; Lee, Jaejun; Sohn, Derac

    2015-05-01

    We report evidence for the possible application of chitosan-coated nickel-ferrite (NiFe2O4) nanoparticles as both T1 and T2 contrast agents in magnetic resonance imaging (MRI). The coating of nickel-ferrite nanoparticles with chitosan was performed simultaneously with the synthesis of the nickel-ferrite nanoparticles by a chemical co-precipitation method. The coated nanoparticles were cylindrical in shape with an average length of 17 nm and an average width of 4.4 nm. The bonding of chitosan onto the ferrite nanoparticles was confirmed by Fourier transform infrared spectroscopy. The T1 and T2 relaxivities were 0.858±0.04 and 1.71±0.03 mM-1 s-1, respectively. In animal experimentation, both a 25% signal enhancement in the T1-weighted mage and a 71% signal loss in the T2-weighted image were observed. This demonstrated that chitosan-coated nickel-ferrite nanoparticles are suitable as both T1 and T2 contrast agents in MRI. We note that the applicability of our nanoparticles as both T1 and T2 contrast agents is due to their cylindrical shape, which gives rise to both inner and outer sphere processes of nanoparticles.

  8. Kinetic of Adsorption of Urea Nitrogen onto Chitosan Coated Dialdehyde Cellulose under Catalysis of Immobilized Urease

    Institute of Scientific and Technical Information of China (English)

    Zu Pei LIANG; Ya Qing FENG; Zhi Yan LIANG; Shu Xian MENG

    2005-01-01

    The adsorption of urea nitrogen onto chitosan coated dialdehyde cellulose (CDAC)under catalysis of immobilized urease in gelatin membrane (IE) was studied in batch system. The pseudo first-order and second-order kinetic models were used to describe the kinetic data, and the rate constants were evaluated. The experimental data fitted well to the second-order kinetic model.

  9. Cellulose acetate/hydroxyapatite/chitosan coatings for improved corrosion resistance and bioactivity

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, Zhenyu; Qin, Jinli [Advanced Biomaterials and Tissue Engineering Center, Huazhong University of Science and Technology, Wuhan 430074 (China); Ma, Jun, E-mail: caltary@gmail.com [Advanced Biomaterials and Tissue Engineering Center, Huazhong University of Science and Technology, Wuhan 430074 (China); Department of Biomedical Engineering, School of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2015-04-01

    Cellulose acetate (CA) nanofibers were deposited on stainless steel plates by electrospinning technique. The composite of hydroxyapatite (HAP) nanoparticles and chitosan (CHI) was coated subsequently by dip-coating. The structure and morphology of the obtained coatings were investigated by Fourier transform infrared spectroscopy and scanning electron microscopy. The stability of the coatings in physiological environment was studied using electrochemical polarization and impedance spectroscopy. The CA nanofibers were embedded in the HAP/CHI coating and the resulted composite film was densely packed and uniform on the substrate. The in vitro biomineralization study of the coated samples immersed in simulated body fluid (SBF) confirmed the formation ability of bone-like apatite layer on the surface of HAP-containing coatings. Furthermore, the coatings could provide corrosion resistance to the stainless steel substrate in SBF. The electrochemical results suggested that the incorporation of CA nanofibers could improve the corrosion resistance of the HAP/CHI coating. Thus, biocompatible CA/HAP/CHI coated metallic implants could be very useful in the long-term stability of the biomedical applications. - Highlights: • The composite coatings were prepared by electrospinning and dip-coating. • Good in vitro bioactivity of the CA/HAP/CHI coating was confirmed. • Electrochemical behaviors in SBF of the coatings have been studied. • The CA/HAP/CHI coating shows better resistance property than HAP/CHI.

  10. Controlled release properties of Chitosan encapsulated volatile Citronella Oil microcapsules by thermal treatments.

    Science.gov (United States)

    Hsieh, Wen-Chuan; Chang, Chih-Pong; Gao, Ying-Lin

    2006-12-01

    This research uses modified orifice method to prepare the O/W type Chitosan encapsulated volatile Citronella Oil microcapsules. In this article, we investigated the forming condition of microcapsules and the influence to sustained release effect of volatile Citronella Oil by applying thermal pretreatment to microcapsules. The results suggest that the forming of microcapsules should be processed under the fundamental conditions of: (1) the concentration of Chitosan is at least 0.2wt%, (2) NaOH is greater than 0.1wt%, and (3) with the additive of coconut oil as natural surfactant, so that we could obtain final product of microcapsules with better formation and dispersion. The changes in concentration of Chitosan will affect the encapsulation efficiency of the volatile Citronella Oil. When the concentrations of Chitosan are 0.5%, 1.0% and 1.5%, the encapsulation efficiencies are 98.2%, 95.8% and 94.7%, respectively. The particle size of Chitosan microcapsules would decrease as the emulsification stirring speed increases. When the stirring speeds are 400 rpm, 800 rpm, and 1500 rpm, the average particle sizes of microcapsules produced are 225+/-24 microm, 131+/-20 microm, and 11+/-3 microm, respectively. If the microcapsules were thermal pretreated at 80 degrees C, the structure of Chitosan wall membrane would shrink and thus achieve the effect of sustained release. The sustaining effect would increase along with treatment time increases.

  11. Chitosan coated carbon fiber microelectrode for selective in vivo detection of neurotransmitters in live zebrafish embryos.

    Science.gov (United States)

    Ozel, Rıfat Emrah; Wallace, Kenneth N; Andreescu, Silvana

    2011-06-10

    We report the development of a chitosan modified carbon fiber microelectrode for in vivo detection of serotonin. We find that chitosan has the ability to reject physiological levels of ascorbic acid interferences and facilitate selective and sensitive detection of in vivo levels of serotonin, a common catecholamine neurotransmitter. Presence of chitosan on the microelectrode surface was investigated using scanning electron microscopy (SEM) and cyclic voltammetry (CV). The electrode was characterized using differential pulse voltammetry (DPV). A detection limit of 1.6 nM serotonin with a sensitivity of 5.12 nA/μM, a linear range from 2 to 100 nM and a reproducibility of 6.5% for n=6 electrodes were obtained. Chitosan modified microelectrodes selectively measure serotonin in presence of physiological levels of ascorbic acid. In vivo measurements were performed to measure concentration of serotonin in the live embryonic zebrafish intestine. The sensor quantifies in vivo intestinal levels of serotonin while successfully rejecting ascorbic acid interferences. We demonstrate that chitosan can be used as an effective coating to reject ascorbic acid interferences at carbon fiber microelectrodes, as an alternative to Nafion, and that chitosan modified microelectrodes are reliable tools for in vivo monitoring of changes in neurotransmitter levels.

  12. Chitosan-coated nickel-ferrite nanoparticles as contrast agents in magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Tanveer [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Department of Physics, Abdul Wali Khan University, Mardan (Pakistan); Bae, Hongsub; Iqbal, Yousaf [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Rhee, Ilsu, E-mail: ilrhee@knu.ac.kr [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Hong, Sungwook [Division of Science Education, Daegu University, Gyeongsan 712-714 (Korea, Republic of); Chang, Yongmin; Lee, Jaejun [Department of Diagnostic Radiology, College of Medicine, Kyungpook National University and Hospital, Daegu 700-721 (Korea, Republic of); Sohn, Derac [Department of Physics, Hannam University, Daejon (Korea, Republic of)

    2015-05-01

    We report evidence for the possible application of chitosan-coated nickel-ferrite (NiFe{sub 2}O{sub 4}) nanoparticles as both T{sub 1} and T{sub 2} contrast agents in magnetic resonance imaging (MRI). The coating of nickel-ferrite nanoparticles with chitosan was performed simultaneously with the synthesis of the nickel-ferrite nanoparticles by a chemical co-precipitation method. The coated nanoparticles were cylindrical in shape with an average length of 17 nm and an average width of 4.4 nm. The bonding of chitosan onto the ferrite nanoparticles was confirmed by Fourier transform infrared spectroscopy. The T{sub 1} and T{sub 2} relaxivities were 0.858±0.04 and 1.71±0.03 mM{sup −1} s{sup −1}, respectively. In animal experimentation, both a 25% signal enhancement in the T{sub 1}-weighted mage and a 71% signal loss in the T{sub 2}-weighted image were observed. This demonstrated that chitosan-coated nickel-ferrite nanoparticles are suitable as both T{sub 1} and T{sub 2} contrast agents in MRI. We note that the applicability of our nanoparticles as both T{sub 1} and T{sub 2} contrast agents is due to their cylindrical shape, which gives rise to both inner and outer sphere processes of nanoparticles. - Highlights: • Chitosan-coated nickel-ferrite (Ni-Fe{sub 2}O{sub 4}) nanoparticles were synthesized in an aqueous system by chemical co-precipitation. • The characterization of bare and chitosan-coated nanoparticles were performed using various analytical tools, such as TEM, FTIR, XRD, and VMS. • We evaluated the coated particles as potential T{sub 1} and T{sub 2} contrast agents for MRI by measuring T{sub 1} and T{sub 2} relaxation times as a function of iron concentration. • Both T{sub 1} and T{sub 2} effects were also observed in animal experimentation.

  13. Development and characterization of an edible composite film based on chitosan and virgin coconut oil with improved moisture sorption properties.

    Science.gov (United States)

    Binsi, P K; Ravishankar, C N; Srinivasa Gopal, T K

    2013-04-01

    An edible composite film was prepared from an emulsion system based on chitosan and virgin coconut oil (VCO). The effect of incorporation of VCO was evaluated at various concentrations and the optimum concentration was chosen based on resultant changes in the properties of the film. Addition of VCO in film forming solution resulted in increase in film thickness and marginal reduction in film transparency. Compatibility of VCO with chitosan was better at lower concentration of VCO as indicated by the microstructure of composite film in scanning electron micrographs. Phase separation was evident at higher level of oil incorporation and the optimal oil/chitosan ratio was determined to be at 0.5 to 1 mL/g chitosan. Furthermore, chemical interaction took place between VCO and chitosan as revealed by Fourier transform infrared spectroscopy data. Even though control chitosan films exhibited superior gas barrier properties, composite film with optimum VCO concentration revealed better mechanical and moisture sorption properties.

  14. Alternating Current Electrophoretic Deposition of Antibacterial Bioactive Glass-Chitosan Composite Coatings

    Directory of Open Access Journals (Sweden)

    Sigrid Seuss

    2014-07-01

    Full Text Available Alternating current (AC electrophoretic deposition (EPD was used to produce multifunctional composite coatings combining bioactive glass (BG particles and chitosan. BG particles of two different sizes were used, i.e., 2 μm and 20–80 nm in average diameter. The parameter optimization and characterization of the coatings was conducted by visual inspection and by adhesion strength tests. The optimized coatings were investigated in terms of their hydroxyapatite (HA forming ability in simulated body fluid (SBF for up to 21 days. Fourier transform infrared (FTIR spectroscopy results showed the successful HA formation on the coatings after 21 days. The first investigations were conducted on planar stainless steel sheets. In addition, scaffolds made from a TiAl4V6 alloy were considered to show the feasibility of coating of three dimensional structures by EPD. Because both BG and chitosan are antibacterial materials, the antibacterial properties of the as-produced coatings were investigated using E. coli bacteria cells. It was shown that the BG particle size has a strong influence on the antibacterial properties of the coatings.

  15. Effects of a chitosan membrane coated with polylactic and polyglycolic acid on bone regeneration in a rat calvarial defect

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Ui-Won [Department of Periodontology, Research Institute for Periodontal Regeneration, College of Dentistry, Yonsei University, 134 Shinchon-Dong, Seodaemun-gu, Seoul 120-752l (Korea, Republic of); Song, Kun-Young [Department of Periodontology, Research Institute for Periodontal Regeneration, College of Dentistry, Yonsei University, 134 Shinchon-Dong, Seodaemun-gu, Seoul 120-752l (Korea, Republic of); Kim, Chang-Sung [Department of Periodontology, Research Institute for Periodontal Regeneration, College of Dentistry, Yonsei University, 134 Shinchon-Dong, Seodaemun-gu, Seoul 120-752l (Korea, Republic of); Lee, Yong-Keun [Department and Research Institute of Dental Biomaterials and Bioengineering, College of Dentistry, Yonsei University, 134 Shinchon-Dong, Seodaemun-gu, Seoul 120-750 (Korea, Republic of); Cho, Kyoo-Sung [Department of Periodontology, Research Institute for Periodontal Regeneration, College of Dentistry, Yonsei University, 134 Shinchon-Dong, Seodaemun-gu, Seoul 120-752l (Korea, Republic of); Kim, Chong-Kwan [Department of Periodontology, Research Institute for Periodontal Regeneration, College of Dentistry, Yonsei University, 134 Shinchon-Dong, Seodaemun-gu, Seoul 120-752l (Korea, Republic of); Choi, Seong-Ho [Department of Periodontology, Research Institute for Periodontal Regeneration, College of Dentistry, Yonsei University, 134 Shinchon-Dong, Seodaemun-gu, Seoul 120-752l (Korea, Republic of)

    2007-09-15

    The purpose of this study was to evaluate the effects of a chitosan membrane coated with polylactic and polyglycolic acid (PLGA) on bone regeneration in a rat calvarial defect. Surgical implantation of chitosan membranes resulted in enhanced local bone formation at both 2 and 8 weeks. In conclusion, the chitosan membrane coated with PLGA had a significant potential to induce bone formation in the rat calvarial defect model. Within the selected PLGA dose range and observation intervals, there appeared to be no meaningful differences in bone formation.

  16. Biodegradable chitosan nanoparticle coatings on titanium for the delivery of BMP-2.

    Science.gov (United States)

    Poth, Nils; Seiffart, Virginia; Gross, Gerhard; Menzel, Henning; Dempwolf, Wibke

    2015-01-08

    A simple method for the functionalization of a common implant material (Ti6Al4V) with biodegradable, drug loaded chitosan-tripolyphosphate (CS-TPP) nanoparticles is developed in order to enhance the osseointegration of endoprostheses after revision operations. The chitosan used has a tailored degree of acetylation which allows for a fast biodegradation by lysozyme. The degradability of chitosan is proven via viscometry. Characteristics and degradation of nanoparticles formed with TPP are analyzed using dynamic light scattering. The particle degradation via lysozyme displays a decrease in particle diameter of 40% after 4 days. Drug loading and release is investigated for the nanoparticles with bone morphogenetic protein 2 (BMP-2), using ELISA and the BRE luciferase test for quantification and bioactivity evaluation. Furthermore, nanoparticle coatings on titanium substrates are created via spray-coating and analyzed by ellipsometry, scanning electron microscopy and X-ray photoelectron spectroscopy. Drug loaded nanoparticle coatings with biologically active BMP-2 are obtained in vitro within this work. Additionally, an in vivo study in mice indicates the dose dependent induction of ectopic bone growth through CS-TPP-BMP-2 nanoparticles. These results show that biodegradable CS-TPP coatings can be utilized to present biologically active BMP-2 on common implant materials like Ti6Al4V.

  17. Biodegradable Chitosan Nanoparticle Coatings on Titanium for the Delivery of BMP-2

    Directory of Open Access Journals (Sweden)

    Nils Poth

    2015-01-01

    Full Text Available A simple method for the functionalization of a common implant material (Ti6Al4V with biodegradable, drug loaded chitosan-tripolyphosphate (CS-TPP nanoparticles is developed in order to enhance the osseointegration of endoprostheses after revision operations. The chitosan used has a tailored degree of acetylation which allows for a fast biodegradation by lysozyme. The degradability of chitosan is proven via viscometry. Characteristics and degradation of nanoparticles formed with TPP are analyzed using dynamic light scattering. The particle degradation via lysozyme displays a decrease in particle diameter of 40% after 4 days. Drug loading and release is investigated for the nanoparticles with bone morphogenetic protein 2 (BMP-2, using ELISA and the BRE luciferase test for quantification and bioactivity evaluation. Furthermore, nanoparticle coatings on titanium substrates are created via spray-coating and analyzed by ellipsometry, scanning electron microscopy and X-ray photoelectron spectroscopy. Drug loaded nanoparticle coatings with biologically active BMP-2 are obtained in vitro within this work. Additionally, an in vivo study in mice indicates the dose dependent induction of ectopic bone growth through CS-TPP-BMP-2 nanoparticles. These results show that biodegradable CS-TPP coatings can be utilized to present biologically active BMP-2 on common implant materials like Ti6Al4V.

  18. Chemical, biochemical, and microbiological aspects of chitosan quaternary salt as active coating on sliced apples

    Directory of Open Access Journals (Sweden)

    Douglas de Britto

    2012-09-01

    Full Text Available The biocompatibility of chitosan and chitosan quaternary salt coatings was evaluated for use as edible coatings for sliced apple. Measurement of water loss, color change, and fungal growth appearance were monitored as a function of time. A significant brownish effect was observed on chitosan coated slices, varying greatly from L* = 76.5 and Hue angle = 95.9° (t = 0 to L* = 45.3 and Hue angle = 69.8° (t = 3 days, whilst for TMC coated samples the variation was considerable lower (L* = 74.1; Hue angle = 95.0° to (L* = 67.0; Hue angle = 83.8° within the same period. The hydrosoluble derivative N,N,N-trimethylchitosan demonstrated good antifungal activity against P. expansum although highly dependent on the polymer properties such as degree of quaternization. The most efficient formulation was that prepared from derivative having a degree of quaternization of 45%, high solubility, and high viscosity. This formulation restrained fungus spreading up to 30%, while for the control it reached almost 80% of the total assessed surfaces during 7 days of storage.

  19. Synthesis optimization and characterization of chitosan-coated iron oxide nanoparticles produced for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Unsoy, Gozde, E-mail: gozdeunsoy@hotmail.com [Middle East Technical University, Department of Biotechnology (Turkey); Yalcin, Serap [Middle East Technical University, Department of Biological Sciences (Turkey); Khodadust, Rouhollah [Middle East Technical University, Department of Biotechnology (Turkey); Gunduz, Gungor [Middle East Technical University, Department of Chemical Engineering (Turkey); Gunduz, Ufuk, E-mail: ufukg@metu.edu.tr [Middle East Technical University, Department of Biological Sciences (Turkey)

    2012-11-15

    The chitosan-coated magnetic nanoparticles (CS MNPs) were in situ synthesized by cross-linking method. In this method; during the adsorption of cationic chitosan molecules onto the surface of anionic magnetic nanoparticles (MNPs) with electrostatic interactions, tripolyphosphate (TPP) is added for ionic cross-linking of the chitosan molecules with each other. The characterization of synthesized nanoparticles was performed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS/ESCA), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), dynamic light scattering (DLS), thermal gravimetric analysis (TGA), and vibrating sample magnetometry (VSM) analyses. The XRD and XPS analyses proved that the synthesized iron oxide was magnetite (Fe{sub 3}O{sub 4}). The layer of chitosan on the magnetite surface was confirmed by FTIR. TEM results demonstrated a spherical morphology. In the synthesis, at higher NH{sub 4}OH concentrations, smaller sized nanoparticles were obtained. The average diameters were generally between 2 and 8 nm for CS MNPs in TEM and between 58 and 103 nm in DLS. The average diameters of bare MNPs were found as around 18 nm both in TEM and DLS. TGA results indicated that the chitosan content of CS MNPs were between 15 and 23 % by weight. Bare and CS MNPs were superparamagnetic. These nanoparticles were found non-cytotoxic on cancer cell lines (SiHa, HeLa). The synthesized MNPs have many potential applications in biomedicine including targeted drug delivery, magnetic resonance imaging (MRI), and magnetic hyperthermia.

  20. Antimicrobial chitosan-lysozyme (CL) films and coatings for enhancing microbial safety of mozzarella cheese.

    Science.gov (United States)

    Duan, J; Park, S-I; Daeschel, M A; Zhao, Y

    2007-11-01

    This study investigated the antimicrobial activities of chitosan-lysozyme (CL) composite films and coatings against tested microorganisms inoculated onto the surface of Mozzarella cheese. CL film-forming solutions (FFS) with a pH of 4.4 to 4.5 were prepared by incorporating 0% or 60% lysozyme (per dry weight of chitosan) into chitosan FFS with or without a pH adjustment to 5.2. Sliced cheese was subjected to 3 CL package applications: film, lamination on a multilayer coextruded film, and coating. Cheese was inoculated with Listeria monocytogenes, Escherichia coli, or Pseudomonas fluorescens at 10(4) CFU/g, or with mold and yeast at 10(2) CFU/g. Inoculated cheese was individually vacuum packaged and stored at 10 degrees C for sampling at 1, 7, and 14 d for bacteria, and at 10, 20, and 30 d for fungi. Inoculated bacteria survived but failed to multiply in untreated cheese during storage. Treated cheese received 0.43- to 1.25-, 0.40- to 1.40-, and 0.32- to 1.35-log reductions in E. coli, P. fluorescens, and L. monocytogenes, respectively. Incorporation of 60% lysozyme in chitosan FFS showed greater antimicrobial effect than chitosan alone on P. fluorescens and L. monocytogenes. The pH adjustment only affected the antimicrobial activity on L. monocytogenes, with lower pH (unadjusted) showing greater antimicrobial effect than pH 5.2. Mold and yeast increased to 10(5) CFU/g in untreated cheese after 30 d storage. Growth of mold was completely inhibited in cheese packaged with CL films, while 0.24- to 1.90- and 0.06- to 0.50-log reductions in mold populations were observed in cheese packaged with CL-laminated films and coatings, respectively. All CL packaging applications resulted in 0.01- to 0.64-log reduction in yeast populations.

  1. Chitosan-coated magnetic nanoparticles prepared in one step by reverse microemulsion precipitation.

    Science.gov (United States)

    López, Raúl G; Pineda, María G; Hurtado, Gilberto; León, Ramón Díaz de; Fernández, Salvador; Saade, Hened; Bueno, Darío

    2013-09-27

    Chitosan-coated magnetic nanoparticles (CMNP) were obtained at 70 °C and 80 °C in a one-step method, which comprises precipitation in reverse microemulsion in the presence of low chitosan concentration in the aqueous phase. X-ray diffractometry showed that CMNP obtained at both temperatures contain a mixture of magnetite and maghemite nanoparticles with ≈4.5 nm in average diameter, determined by electron microscopy, which suggests that precipitation temperature does not affect the particle size. The chitosan coating on nanoparticles was inferred from Fourier transform infrared spectrometry measurements; furthermore, the carbon concentration in the nanoparticles allowed an estimation of chitosan content in CMNP of 6%-7%. CMNP exhibit a superparamagnetic behavior with relatively high final magnetization values (≈49-53 emu/g) at 20 kOe and room temperature, probably due to a higher magnetite content in the mixture of magnetic nanoparticles. In addition, a slight direct effect of precipitation temperature on magnetization was identified, which was ascribed to a possible higher degree of nanoparticles crystallinity as temperature at which they are obtained increases. Tested for Pb2+ removal from a Pb(NO3)2 aqueous solution, CMNP showed a recovery efficacy of 100%, which makes them attractive for using in heavy metals ion removal from waste water.

  2. Fabrication and characterization of Mg-doped chitosan-gelatin nanocompound coatings for titanium surface functionalization.

    Science.gov (United States)

    Cai, Xinjie; Cai, Jing; Ma, Kena; Huang, Pin; Gong, Lingling; Huang, Dan; Jiang, Tao; Wang, Yining

    2016-07-01

    Titanium and its alloys have been widely used in clinic and achieved great success. Due to the bio-inertness of titanium surface, challenges still exit in some compromised conditions. The present study aimed to functionalize titanium surface with magnesium (Mg)-doped chitosan/gelatin (CS/G) nanocompound coatings via electrophoretic deposition (EPD). CS/G coatings loaded with different amount of magnesium were successfully prepared on titanium substrate via EPD. Physicochemical characterization of the coatings confirmed that magnesium ions were loaded into the coatings in a dose-dependent manner. XRD results demonstrated that co-deposition of magnesium influenced the crystallinity of the coatings, and a new crystalline substance presented, namely hydrated basic magnesium carbonate. Mechanical tests showed improved tensile and shear bond strength of the magnesium-doped coatings, while the excessively high magnesium concentration could eventually decrease the bonding strength. Sustained release of magnesium ion was detected by ICP-OES within 28 days. TEM images also displayed that nanoparticles could be released from the coatings. In vitro cellular response assays demonstrated that the Mg-doped nanocompound coatings could enhance the proliferation and osteogenic differentiation of MC3T3-E1 cells compared to CS/G coatings. Therefore, it could be concluded that Mg-doped CS/G nanocompound coatings were successfully fabricated on titanium substrates via EPD. It would be a promising candidate to functionalize titanium surface with such organic-inorganic nanocompound coatings.

  3. Preparation and characterization of chitosan-silver/hydroxyapatite composite coatings onTiO{sub 2} nanotube for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Yajing [Institute of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054 (China); Zhang, Xuejiao [Medical Informatics, Hebei North University, Zhangjiakou 075000 (China); Li, Caixia [Institute of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054 (China); Huang, Yong [Institute of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054 (China); College of Lab Medicine, Hebei North University, Zhangjiakou 075000 (China); Ding, Qiongqiong [Institute of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054 (China); Pang, Xiaofeng, E-mail: xfpang@aliyun.com [Institute of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054 (China)

    2015-03-30

    Highlights: • Chitosan/silver-doped hydroxyapatite biocomposite coating was successfully deposited on anodized Ti by electrochemical deposition. • The chemical state of silver in the synthesized coatings was studied by XPS peak deconvolution. • The synthesized coatings have excellent antibacterial activity because of synergistic effect of the Ag and CS. • The CSAgHAp coatings showed good biocompatibility and no adverse effect in cell culture tests. - Abstract: A biocomposite coating containing chitosan, silver, and hydroxyapatite was developed on anodized titanium substrate by electrochemical deposition. Coatings were characterized by field-emission scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and polarisation studies. Results showed that the prepared coatings had compact and dense morphology with a thickness of 6.2 ± 0.7 μm and that silver was evenly distributed. Testing the prepared coatings with Gram-positive and Gram-negative bacterial strains exhibited antibacterial activity because of the synergistic effect of silver and chitosan. The prepared coatings were also found to be nontoxic to MC3T3-E1 cells. These results suggested that chitosan/silver-hydroxyapatite biocomposite coatings can prevent the bacterial infection of implants.

  4. Chitosan-pectin hybrid nanoparticles prepared by coating and blending techniques.

    Science.gov (United States)

    Rampino, A; Borgogna, M; Bellich, B; Blasi, P; Virgilio, F; Cesàro, A

    2016-03-10

    The preparation of chitosan nanoparticles in combination with pectins, as additional mucoadhesive biopolymers, was investigated. Pectins from apple and from citrus fruit were considered; polygalacturonic acid was taken as a reference. Tripolyphosphate was used as an anionic cross-linker. Two different techniques were compared, namely the coating and the blending. Coated nanoparticles (NPs) in the ratio pectin:NPs from 2:1 to 5:1 evidenced that the size of NPs increased as the amount of pectin (both from apple and citrus fruit) was increased. In particular, for NPs coated with pectin from citrus fruit the size ranges from 200 to 260nm; while for NPs coated with pectin from apple the size ranges from 330 to 450nm. A minimum value of Z-potential around -35mV was obtained for the ratio pectin:NPs 4:1, while further addition of pectin did not decrease the Z-potential. Also blended NPs showed a dependence of the size on the ratio of the components: for a given ratio pectin:tripolyphosphate the size increases as the fraction of chitosan increases; for a low ratio chitosan:pectin a high amount of tripolyphosphate was needed to obtain a compact structure. The effect of the additional presence of loaded proteins in chitosan-pectin nanoparticles was also investigated, since proteins contribute to alter the electrostatic interactions among charged species. FT-IR and DSC characterization are presented to confirm the interactions between biopolymers. Finally, the biocompatibility of the used materials was assessed by the chorioallantoic membrane assay, confirming the safety of the materials.

  5. Synthesis of chitosan/hydroxyapatite membranes coated with hydroxycarbonate apatite for guided tissue regeneration purposes

    Science.gov (United States)

    Fraga, Alexandre Félix; Filho, Edson de Almeida; Rigo, Eliana Cristina da Silva; Boschi, Anselmo Ortega

    2011-02-01

    Chitosan, which is a non-toxic, biodegradable and biocompatible biopolymer, has been widely researched for several applications in the field of biomaterials. Calcium phosphate ceramics stand out among the so-called bioceramics for their absence of local or systemic toxicity, their non-response to foreign bodies or inflammations, and their apparent ability to bond to the host tissue. Hydroxyapatite (HA) is one of the most important bioceramics because it is the main component of the mineral phase of bone. The aim of this work was to produce chitosan membranes coated with hydroxyapatite using the modified biomimetic method. Membranes were synthesized from a solution containing 2% of chitosan in acetic acid (weight/volume) via the solvent evaporation method. Specimens were immersed in a sodium silicate solution and then in a 1.5 SBF (simulated body fluid) solution. The crystallinity of the HA formed over the membranes was correlated to the use of the nucleation agent (the sodium silicate solution itself). Coated membranes were characterized by means of scanning electron microscopy - SEM, X-ray diffraction - XRD, and Fourier transform infrared spectroscopy - FTIR. The results indicate a homogeneous coating covering the entire surface of the membrane and the production of a semi-crystalline hydroxyapatite layer similar to the mineral phase of human bone.

  6. Synthesis of chitosan/hydroxyapatite membranes coated with hydroxycarbonate apatite for guided tissue regeneration purposes

    Energy Technology Data Exchange (ETDEWEB)

    Fraga, Alexandre Felix [Federal University of Sao Carlos, Department of Materials Engineering, DEMa, UFSCar, Sao Carlos, SP (Brazil); Almeida Filho, Edson de, E-mail: edsonafilho@yahoo.com.br [University Estadual Paulista, Department of Physical Chemistry - IQ, Araraquara, SP (Brazil); Silva Rigo, Eliana Cristina da [University of Sao Paulo, Department of Basic Science - FZEA-ZAB, Pirassununga, SP (Brazil); Ortega Boschi, Anselmo [Federal University of Sao Carlos, Department of Materials Engineering, DEMa, UFSCar, Sao Carlos, SP (Brazil)

    2011-02-15

    Chitosan, which is a non-toxic, biodegradable and biocompatible biopolymer, has been widely researched for several applications in the field of biomaterials. Calcium phosphate ceramics stand out among the so-called bioceramics for their absence of local or systemic toxicity, their non-response to foreign bodies or inflammations, and their apparent ability to bond to the host tissue. Hydroxyapatite (HA) is one of the most important bioceramics because it is the main component of the mineral phase of bone. The aim of this work was to produce chitosan membranes coated with hydroxyapatite using the modified biomimetic method. Membranes were synthesized from a solution containing 2% of chitosan in acetic acid (weight/volume) via the solvent evaporation method. Specimens were immersed in a sodium silicate solution and then in a 1.5 SBF (simulated body fluid) solution. The crystallinity of the HA formed over the membranes was correlated to the use of the nucleation agent (the sodium silicate solution itself). Coated membranes were characterized by means of scanning electron microscopy - SEM, X-ray diffraction - XRD, and Fourier transform infrared spectroscopy - FTIR. The results indicate a homogeneous coating covering the entire surface of the membrane and the production of a semi-crystalline hydroxyapatite layer similar to the mineral phase of human bone.

  7. Studies of chitosan/organic acid/Eudragit RS/RL-coated system for colonic delivery.

    Science.gov (United States)

    Kaur, Karanjit; Kim, Kwonho

    2009-01-21

    Prednisolone (PDS) beads were coated sequentially with (i) innermost hydrophobic layer of Eudragit RS/RL, (ii) middle drug release-triggering layer of chitosan, organic acid and Eudragit RS/RL, and (iii) outermost enteric coating layer. Continuous dissolution studies were carried out in artificial gastric fluid (pH 1.2), followed by intestinal fluid (pH 6.8), and finally in colonic fluid (pH 4 and 6) with and without beta-glucosidase. While drug release was prevented in the gastric and small-intestinal fluids, a continuous release was observed in the colonic fluid. Succinic acid provided the fastest rate of release in the colonic fluid compared to citric, tartaric or malic acid. A combined mechanism of drug release is proposed, which considers the swelling of chitosan and Eudragit RS/RL in the presence of succinic acid possibly via electrostatic interaction between the amine groups of chitosan/quaternary ammonium groups of Eudragit RS/RL and the carboxyl groups of succinic acid in aqueous medium. The results of plasma pharmacokinetic studies in Sprague-Dawley rats showed that the developed system provided a significant delay (T(max) 9.3 h) in the absorption profile of PDS compared with simple enteric-coated (T(max) 4 h) or powder (T(max) 1 h) formulation that was taken as proof for the colon-targeted delivery.

  8. Sonochemical coating of textiles with hybrid ZnO/chitosan antimicrobial nanoparticles.

    Science.gov (United States)

    Petkova, Petya; Francesko, Antonio; Fernandes, Margarida M; Mendoza, Ernest; Perelshtein, Ilana; Gedanken, Aharon; Tzanov, Tzanko

    2014-01-22

    Textiles are good substrates for growth of microorganisms especially under moisture and temperature conditions found in hospitals. Microbial shedding from the body occurs continuously at contact of the patient with textile materials used in medical practices, contributing to the occurrence of hospital acquired infections. Thus, the use of efficient antimicrobial textiles is necessary to prevent the transfer of pathogens and the infection incidence. In this work, hybrid antimicrobial coatings were generated on cotton fabrics by means of a one-step simultaneous sonochemical deposition of ZnO nanoparticles (NPs) and chitosan. The process was further optimized in terms of reagents concentration and processing time in order to improve the antibacterial properties of the fabric and ensure their biocompatibility. The highest antibacterial activity of the fabrics against two medically relevant bacterial species was achieved in a 30 min sonochemical coating process using 2 mM ZnO NPs suspension. When chitosan was simultaneously deposited with the same amount of ZnO, the obtained hybrid NPs coating displayed higher by 48 and 17% antibacterial activity against Staphylococcus aureus and Escherichia coli, respectively. The presence of biopolymer also improved the durability of the antimicrobial effect of the coatings by 21% for Staphylococcus aureus and 40% for Escherichia coli, evaluated after applying multiple washing cycles at hospital laundering regimes. Finally, 87% biocompatibility improvement supported by fibroblast viability was observed for the hybrid ZnO/chitosan coating compared to the steady decrease of cells viability over one week in contact with the fabrics coated with ZnO alone.

  9. Effect of chitosan-caraway coating on color stability and lipid oxidation of traditional dry fermented sausage

    Directory of Open Access Journals (Sweden)

    Hromiš Nevena M.

    2013-01-01

    Full Text Available Chitosan, the second most abundant polysaccharide in nature, after cellulose, has been tested for numerous applications, among which for edible film and coating. Chitosan-based coating showed positive results for shelf life prolongation of meet products. In this paper, dry fermented sausage (Petrovská klobása was coated with chitosan-caraway film. The effect of coating on the moisture content, color and lipid oxidation was investigated during a fivemonth period of storage. The moisture content decreased rapidly during the storage and the coating did not slow down the loss of moisture. The Lightness (L* of the sausage surface increased by the coating application, while the redness (a* and yellowness (b* did not change. The coated sausages showed a better color stability of the sausage core through the storage time. Also, coated sausage showed a better oxidative stability till the 60th day of storage, while this difference was not detected at the end of the storage period. Apart from slowing down sausage drying during the storage, chitosan-caraway coating was effective in preserving the sausage quality. [Projekat Ministarstva nauke Republike Srbije, br. TR31032

  10. Antimicrobial Activity of Chitosan Films With Essential Oils Against Listeria monocytogenes on Cabbage

    Science.gov (United States)

    Jovanovic, Gordana D.; Klaus, Anita S.; P. Niksic, Miomir

    2016-01-01

    Background The highest incidence of listeriosis, due to consumption of ready-to-eat foods and fresh, shredded, minimally processed vegetables, occurs among pregnant women and the elderly. In order to reduce the prevalence of listeriosis among consumers, better protective measures are recommended. Chitosan films, with or without added essential oils, represent a modern, safe method of preserving the quality of such vegetables and significantly reducing the incidence of Listeria monocytogenes in these foods. Objectives The present study was conducted to evaluate the antimicrobial properties of composite chitosan-gelatin films with and without essential oils against two strains of L. monocytogenes, ATCC 19115 and ATCC 19112, in fresh shredded cabbage. Methods Shredded cabbage was inoculated with L. monocytogenes and packed between two layers of the chitosan composite film, then placed in Petri dishes. The prepared samples were stored at 4°C then analyzed for total viable count on PALCAM agar while incubated at 37°C, every 24 hours for 7 days. Results Average L. monocytogenes content ranged from 4.2 - 5.4 log CFU/g, reaching values of 7.2 - 8.6 log CFU/g in samples of untreated cabbage. A complete reduction of L. monocytogenes ATCC 19115 on cabbage was achieved after 120 hours in the presence of 0.5% chitosan film, whereas reduction of L. monocytogenes ATCC 19112 was achieved after 144 hours. In the presence of 1% chitosan film, the bacteria withered more quickly and complete reduction of both species of L. monocytogenes was achieved after 96 hours. Conclusions All tested formulations of chitosan films exhibited strong antimicrobial activity on the growth of both strains of L. monocytogenes on cabbage. The best effect was achieved with a 1% chitosan concentration. The addition of essential oils increased the antimicrobial activity of all tested films. PMID:27800143

  11. Effect of composition and properties of chitosan-based edible coatings on microflora of meat and meat products

    Directory of Open Access Journals (Sweden)

    Denis A. Baranenko

    2013-06-01

    Full Text Available Background. Analysis of the properties of various chitosan grades has resulted in a working hypothesis that chitosan can be used as part of protective film-forming coatings for meat and meat products. The aim of this study was the research of composition, properties and antibacterial activity of chitosan-based coatings used for cold storage of meat and meat products. Material and methods. Protective coatings, developed by the authors, based on organic acids and chi- tosan with food gelatin, or distarch glycerol, or wheat fiber, or sodium alginate, or guar gum have been used as research material. The coatings were applied on the surfaces of retail cuts of veal and rabbit meat, boiled sausages, smoked sausages and smoked-boiled pork brisket. Antimicrobial activity of the solutions was evaluated in vitro. Microbial indicators of the mixtures were also determined by the zone of inhibition assay. Dynamic viscosity, the activation energy of viscous flow and pH of mixtures of fluids were measured. During the storage of meat and meat products total viable count of microorganisms was determined. Results. Polymer solutions of chitosan:starch and chitosan:gelatin are technologicaly compatible, solutions of chitosan:fiber are two-phase colloidal systems. Coatings did not alter the samples inherent flavour char- acteristics. All coatings reduced total viable count of microorganisms compared to control samples without coating. Composition based on 2% solution of chitosan and organic acids and 2% gelatin solution in a ratio of 1:1 has the strongest bacteriostatic effect for meat and meat products. Including potassium sorbate and sodium benzoate in gelatin and chitosan solutions mixture for protective coating was not found reasonable, because of their lower bacteriostatic effect. Combined application of vacuum and protective coatings pro- vided the strongest suppressing effect on microflora in all samples. Conclusions.The chitosan-based edible coatings

  12. Soft Tissue Regeneration under the Effect of Wound Coating Based on Chitosan (Natural Biopolymer).

    Science.gov (United States)

    Gladkova, E V; Babushkina, I V; Norkin, I A; Mamonova, I A; Puchin'yan, D M; Konyuchenko, E A

    2016-03-01

    We developed wound coating based on natural biopolymer chitosan with additional components (ceruloplasmin, L-asparaginic acid, and glycerol). Experiments on albino male rats demonstrated its regeneratory, antioxidant, and antibacterial effects on wounds involving all layers of the skin. Due to chemical composition and buffer component, the biodegraded wound coating optimizes all phases of the wound process, accelerates by 22-28% the reparative regeneration, and leads to anatomic and functional restoration of injured sites. High absorption capacity recommends its use in the treatment of wounds with profuse exudation.

  13. Microencapsulation of citronella oil by complex coacervation using chitosan-gelatin (b system: operating design, preparation and characterization

    Directory of Open Access Journals (Sweden)

    Abdul Aziz Fitrah Rabani

    2016-01-01

    Full Text Available Citronella oil (CO can be an effective mosquito repellent, but due to its nature which having high volatility, oils rapidly evaporates causing loss of efficacy and shorten the repellent effect. Therefore, microencapsulation technology was implemented to ensure the encapsulated material being protected from immediate contact with environment and offers controlled release. In this study, microencapsulation of CO was done by employing complex coacervation using chitosan-gelatin (B system and utilized proanthocyanidins as the crosslinker. Remarkably, nearly all material involved in this study are from natural sources which are safe to human and environment. In designing operating process condition for CO encapsulation process, we found that wall ratio of 1:35 and pH 5 was the best operating condition based on zeta potential and turbidity analysis. FT-IR analysis found that gelatin-B had coated the CO droplet during emulsification stage, chitosan started to interact with gelatin-B to form a polyelectrolyte complex in adjust pH stage, CO capsules solidified at cooling process and were hardened during crosslinking process. Final product of CO capsules after settling process was identified at the top layer. Surface morphology of CO capsules obtained in this study were described having diameter varies from 81.63 µm to 156.74 µm with almost spherical in shape.

  14. Preparation of N,O-carboxymethyl chitosan coated alginate microcapsules and their application to Bifidobacterium longum BIOMA 5920

    Energy Technology Data Exchange (ETDEWEB)

    Mi, Yu; Su, Ran [Shaanxi R and D Center of Biomaterials and Fermentation Engineering, School of Chemical Engineering, Northwest University (China); Fan, Dai-Di, E-mail: fandaidi@nwu.edu.cn [Shaanxi R and D Center of Biomaterials and Fermentation Engineering, School of Chemical Engineering, Northwest University (China); Zhu, Xiao-Li [Shaanxi R and D Center of Biomaterials and Fermentation Engineering, School of Urban and Environmental Science, Northwest University, Taibai North Road 229, Xi' an, Shaanxi 710069 (China); Zhang, Wen-Ni [Shaanxi R and D Center of Biomaterials and Fermentation Engineering, School of Chemical Engineering, Northwest University (China); Shaanxi Key Laboratory of Degradable Biomedical Materials, School of Chemical Engineering, Northwest University (China)

    2013-07-01

    In order to greatly improve vitality of probiotic bacteria within the application, a novel biocompatible vehicle, N,O-carboxymethyl chitosan (NOCs) with appropriate degrees of substitution coat alginate (ALg) microparticles, was prepared by electrostatic droplet generation. The amount of chitosan (Cs) and N,O-carboxymethyl chitosan (NOCs) coated on the ALg microparticles was determined by differential scanning calorimetry. The surface morphology of ALg microparticles, Cs coated ALg microparticles and NOCs coated ALg microparticles was determined using scanning electron microscopy. The coating thickness of Cs coated ALg microparticles and that of NOCs coated ALg microparticles was directly observed with confocal laser scanning microscopy. In order to assess pH sensitivity of microparticles, the bovine serum albumin release from the microspheres was tested in acid solution (pH 2.0) for 2 h and subsequently in alkaline solution (pH 7.0) for 2 h. The survival of Bifidobacterium longum BIOMA 5920 loaded in NOCs coated with ALg microparticle was improved in simulated gastric juice (pH 2.0, for 2 h) compared to that of B. longum BIOMA 5920 loaded in ALg microparticles and Cs coated ALg microparticles. After incubation in simulated intestinal juices (pH 7.0, 2 h), the release of microencapsulated B. longum BIOMA 5920 was investigated. - Highlights: • Synthesised N,O-carboxymethyl chitosan (NOCs) coated alginate (ALg) microspheres. • Their effect on intestinal microflora was investigated in simulated gastric juices. • NOCs A coated ALg microspheres improved Bifidobacterium longum survival in SGJ. • The modified chitosan layer improved the pH-response of alginate microspheres. • NOCs A coated microspheres could be used to deliver oral bioactive compounds.

  15. Effect of the addition CNTs on performance of CaP/chitosan/coating deposited on magnesium alloy by electrophoretic deposition

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jie [Department of Neuro Intern, First Affiliated Hospital of Harbin Medical University, Harbin 150001 (China); Pharmaceutical Research Institute in Heilongjiang Province, Jiamusi University, Jiamusi 154007 (China); Wen, Zhaohui, E-mail: wenzhaohui1968@163.com [Department of Neuro Intern, First Affiliated Hospital of Harbin Medical University, Harbin 150001 (China); Zhao, Meng [Department of Neuro Intern, First Affiliated Hospital of Harbin Medical University, Harbin 150001 (China); Li, Guozhong, E-mail: hydlgz1962@163.com [Department of Neuro Intern, First Affiliated Hospital of Harbin Medical University, Harbin 150001 (China); Dai, Changsong, E-mail: changsd@hit.edu.cn [School of Chemistry Engineering and Technology, Harbin Institute of Technology, Harbin 150001 (China)

    2016-01-01

    CaP/chitosan/carbon nanotubes (CNTs) coating on AZ91D magnesium alloy was prepared via electrophoretic deposition (EPD) followed by conversion in a phosphate buffer solution (PBS). The bonding between the layer and the substrate was studied by an automatic scratch instrument. The phase compositions and microstructures of the composite coatings were determined by using X-ray diffraction (XRD), Fourier-transformed infrared spectroscopy (FTIR), Raman spectroscopy and scanning electron microscope (SEM). The element concentration and gentamicin concentration were respectively determined by inductively coupled plasma optical emission spectrometer (ICP-OES) test and ultraviolet spectrophotometer (UV). The cell counting kit (CCK) assay was used to evaluate the cytotoxicity of samples to SaOS-2 cells. The results showed that a few CNTs with their original tubular morphology could be found in the CaP/chitosan coating and they were beneficial for the crystal growth of phosphate and improvement of the coating bonding when the addition amount of CNTs in 500 ml of electrophoretic solution was from 0.05 g to 0.125 g. The loading amount of gentamicin increased and the releasing speed of gentamicin decreased after CNTs was added into the CaP/chitosan coating for immersion loading and EPD loading. The cell viability of Mg based CaP/chitosan/CNTs was higher than that of Mg based CaP/chitosan from 16 days to 90 days. - Highlights: • CaP/chitosan/CNTs coating on AZ91D was prepared. • The addition of CNTs could improve the performance of CaP/chitosan coating. • A new method of loading gentamicin by EPD was proposed.

  16. Crayfish chitosan for microencapsulation of coriander (Coriandrum sativum L.) essential oil.

    Science.gov (United States)

    Duman, Fatih; Kaya, Murat

    2016-11-01

    In this study, chitosan, which was obtained from the waste shells of crayfish (Astacus leptodactylus), was used for the encapsulation of the essential oil isolated from coriander (Coriandrum sativum L.) via the spray drying method. The obtained capsules were characterized using SEM, FT-IR, TGA and XRD. The size of the microcapsules was between 400nm - 7μm. It was determined that the swelling characteristic of the capsules was pH sensitive. The release showed bi-phasic characteristics and the maximum degree was reached after 72h. Antimicrobial activity studies showed that pure chitosan more effective than the capsule. The antioxidant activity was recorded concentration-dependent. In contrast the antimicrobial activity, antioxidant activity of the capsule was found much higher than the oil and the pure chitosan. Consequently, it was determined that this product could be used in the food and pharmaceutical industries as a natural antioxidant and antimicrobial agent.

  17. Mechanically stable antimicrobial chitosan-PVA-silver nanocomposite coatings deposited on titanium implants.

    Science.gov (United States)

    Mishra, Sandeep K; Ferreira, J M F; Kannan, S

    2015-05-05

    Bionanocomposite coatings with antimicrobial activity comprising polyvinyl alcohol (PVA)-capped silver nanoparticles embedded in chitosan (CS) matrix were developed by a green soft chemistry synthesis route. Colloidal sols of PVA-capped silver nanoparticles (AgNPs) were synthesized by microwave irradiating an aqueous solution comprising silver nitrate and PVA. The bionanocomposites were prepared by adding an aqueous solution of chitosan to the synthesized PVA-capped AgNPs sols in appropriate ratios. Uniform bionanocomposite coatings with different contents of PVA-capped AgNPs were deposited onto titanium substrates by "spread casting" followed by solvent evaporation. Nanoindentation and antimicrobial activity tests performed on CS and bionanocomposites revealed that the incorporation of PVA-capped AgNPs enhanced the overall functional properties of the coatings, namely their mechanical stability and bactericidal activity against Escherichia coli and Staphylococcus aureus. The coated specimens maintained their antimicrobial activity for 8h due to the slow sustained release of silver ions. The overall benefits for the relevant functional properties of the coatings were shown increase with increasing contents of PVA-capped AgNPs in the bionanocomposites.

  18. Polyelectrolyte films based on chitosan/olive oil and reinforced with cellulose nanocrystals.

    Science.gov (United States)

    Pereda, Mariana; Dufresne, Alain; Aranguren, Mirta I; Marcovich, Norma E

    2014-01-30

    Composite films designed as potentially edible food packaging were prepared by casting film-forming emulsions based on chitosan/glycerol/olive oil containing dispersed cellulose nanocrystals (CNs). The combined use of cellulose nanoparticles and olive oil proved to be an efficient method to reduce the inherently high water vapor permeability of plasticized chitosan films, improving at the same time their tensile behavior. At the same time, it was found that the water solubility slightly decreased as the cellulose content increased, and further decreased with oil addition. Unexpectedly, opacity decreased as cellulose content increased, which balanced the reduced transparency due to lipid addition. Contact angle decreased with CN addition, but increased when olive oil was incorporated. Results from dynamic mechanical tests revealed that all films present two main relaxations that could be ascribed to the glycerol- and chitosan-rich phases, respectively. The response of plasticized chitosan-nanocellulose films (without lipid addition) was also investigated, in order to facilitate the understanding of the effect of both additives.

  19. Natural Minerals Coated by Biopolymer Chitosan: Synthesis, Physicochemical, and Adsorption Properties

    Science.gov (United States)

    Budnyak, T. M.; Yanovska, E. S.; Kichkiruk, O. Yu.; Sternik, D.; Tertykh, V. A.

    2016-11-01

    Natural minerals are widely used in treatment technologies as mineral fertilizer, food additive in animal husbandry, and cosmetics because they combine valuable ion-exchanging and adsorption properties together with unique physicochemical and medical properties. Saponite (saponite clay) of the Ukrainian Podillya refers to the class of bentonites, a subclass of layered magnesium silicate montmorillonite. Clinoptilolits are aluminosilicates with carcase structure. In our work, we have coated biopolymer chitosan on the surfaces of natural minerals of Ukrainian origin — Podilsky saponite and Sokyrnitsky clinoptilolite. Chitosan mineral composites have been obtained by crosslinking of adsorbed biopolymer on saponite and clinoptilolite surface with glutaraldehyde. The obtained composites have been characterized by the physicochemical methods such as thermogravimetric/differential thermal analyses (DTA, DTG, TG), differential scanning calorimetry, mass analysis, nitrogen adsorption/desorption isotherms, scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) spectroscopy to determine possible interactions between the silica and chitosan molecule. The adsorption of microquantities of cations Cu(II), Zn(II), Fe(III), Cd(II), and Pb(II) by the obtained composites and the initial natural minerals has been studied from aqueous solutions. The sorption capacities and kinetic adsorption characteristics of the adsorbents were estimated. It was found that the obtained results have shown that the ability of chitosan to coordinate heavy metal ions Zn(II), Cu(II), Cd(II), and Fe(III) is less or equal to the ability to retain ions of these metals in the pores of minerals without forming chemical bonds.

  20. Electrospinning chitosan/poly(ethylene oxide) solutions with essential oils: Correlating solution rheology to nanofiber formation.

    Science.gov (United States)

    Rieger, Katrina A; Birch, Nathan P; Schiffman, Jessica D

    2016-03-30

    Electrospinning hydrophilic nanofiber mats that deliver hydrophobic agents would enable the development of new therapeutic wound dressings. However, the correlation between precursor solution properties and nanofiber morphology for polymer solutions electrospun with or without hydrophobic oils has not yet been demonstrated. Here, cinnamaldehyde (CIN) and hydrocinnamic alcohol (H-CIN) were electrospun in chitosan (CS)/poly(ethylene oxide) (PEO) nanofiber mats as a function of CS molecular weight and degree of acetylation (DA). Viscosity stress sweeps determined how the oils affected solution viscosity and chain entanglement (Ce) concentration. Experimentally, the maximum polymer:oil mass ratio electrospun was 1:3 and 1:6 for CS/PEO:CIN and:H-CIN, respectively; a higher chitosan DA increased the incorporation of H-CIN only. The correlations determined for electrospinning plant-derived oils could potentially be applied to other hydrophobic molecules, thus broadening the delivery of therapeutics from electrospun nanofiber mats.

  1. Curcumin-Loaded Chitosan-Coated Nanoparticles as a New Approach for the Local Treatment of Oral Cavity Cancer.

    Science.gov (United States)

    Mazzarino, Leticia; Loch-Neckel, Gecioni; Bubniak, Lorena Dos Santos; Mazzucco, Suelen; Santos-Silva, Maria Cláudia; Borsali, Redouane; Lemos-Senna, Elenara

    2015-01-01

    Mucoadhesive nanoparticles loaded with curcumin were developed as a new approach to deliver curcumin for the local treatment of oral cancer. PCL nanoparticles coated with chitosan displaying different molar masses were prepared by using the nanoprecipitation technique. The mucoadhesive properties of nanoparticle suspensions were demonstrated by their strong ability to interact with the glycoprotein mucin through electrostatic interactions. Similar permeation profiles of curcumin loaded in uncoated and chitosan-coated nanoparticles across porcine esophageal mucosa were verified. Curcumin concentrations retained in the mucosa suggest the possibility of a local effect of the drug. In vitro studies demonstrated that free curcumin.and curcumin loaded into nanoparticles coated with chitosan caused significant reduction of SCC-9 human oral cancer cell viability in a concentration and time-dependent manner. However, no significant cell death was observed after 24 h of treatment with unloaded nanoparticles coated with chitosan. In addition, curcumin-loaded nanoparticles showed reduced cytotoxicity, when compared with the free drug. Therefore, chitosan-coated PCL nanoparticles may be considered a promising strategy to deliver curcumin directly into the oral cavity for the treatment of oral cancer.

  2. Antifungal activity by vapor contact of essential oils added to amaranth, chitosan, or starch edible films.

    Science.gov (United States)

    Avila-Sosa, Raúl; Palou, Enrique; Jiménez Munguía, María Teresa; Nevárez-Moorillón, Guadalupe Virginia; Navarro Cruz, Addí Rhode; López-Malo, Aurelio

    2012-02-01

    Antimicrobial agents can be incorporated into edible films to provide microbiological stability, since films can be used as carriers of a variety of additives to extend product shelf life and reduce the risk of microbial growth on food surfaces. Addition of antimicrobial agents to edible films offers advantages such as the use of small antimicrobial concentrations and low diffusion rates. The aim of this study was to evaluate inhibition by vapor contact of Aspergillus niger and Penicillium digitatum by selected concentrations of Mexican oregano (Lippia berlandieri Schauer), cinnamon (Cinnamomum verum) or lemongrass (Cymbopogon citratus) essential oils (EOs) added to amaranth, chitosan, or starch edible films. Essential oils were characterized by gas chromatography-mass spectrometry (GC/MS) analysis. Amaranth, chitosan and starch edible films were formulated with essential oil concentrations of 0.00, 0.25, 0.50, 0.75, 1.00, 2.00, or 4.00%. Antifungal activity was evaluated by determining the mold radial growth on agar media inoculated with A. niger and P. digitatum after exposure to vapors arising from essential oils added to amaranth, chitosan or starch films using the inverted lid technique. The modified Gompertz model adequately described mold growth curves (mean coefficient of determination 0.991 ± 0.05). Chitosan films exhibited better antifungal effectiveness (inhibition of A. niger with 0.25% of Mexican oregano and cinnamon EO; inhibition of P. digitatum with 0.50% EOs) than amaranth films (2.00 and 4.00% of cinnamon and Mexican oregano EO were needed to inhibit the studied molds, respectively). For chitosan and amaranth films a significant increase (pfilm concentrations while a significant decrease (pedible films incorporating Mexican oregano or cinnamon essential oil could improve the quality of foods by the action of the volatile compounds on surface growth of molds.

  3. Chitosan dipping or oregano oil treatments, singly or combined on modified atmosphere packaged chicken breast meat.

    Science.gov (United States)

    Petrou, S; Tsiraki, M; Giatrakou, V; Savvaidis, I N

    2012-06-01

    The present study examined the effect of natural antimicrobials: chitosan, oregano and their combination, on the shelf-life of modified atmosphere packaged chicken breast meat stored at 4°C. Treatments examined in the present study were the following: M (control samples stored under modified atmosphere packaging), M-O (samples treated with oregano oil 0.25% v/w, stored under MAP), M-CH (samples treated with chitosan 1.5% w/v, stored under MAP) and M-CH-O (treated with chitosan 1.5% w/v and oregano oil 0.25% v/w, stored under MAP). Treatment, M-CH-O, significantly affected mesophilic Total Plate Counts (TPC), lactic acid bacteria (LAB), Brochothrix thermosphacta, Enterobacteriaceae, Pseudomonas spp., and yeasts-moulds during the storage period. Lipid oxidation (as determined by MDA values) of control and treated chicken samples was in general low and below 0.5 mg MDA/kg, showing no oxidative rancidity during the storage period. Addition of chitosan to the chicken samples produced higher (Poregano oil singly, and/or chitosan, by approximately 6 (M-O) and >15 (M-CH and M-CH-O) days. Interestingly, chitosan (M-CH) or chitosan-oregano (M-CH-O) treated chicken samples were sensorially acceptable during the entire refrigerated storage period of 21 days. It is noteworthy that the presence of chitosan in M-CH and M-CH-O samples did not negatively influence the taste of chicken samples, with M-CH samples receiving a higher score (compared to M-CH-O), probably as a result of a distinct and "spicy" lemon taste of chitosan, that was well received by the panelists. Based primarily on sensory data (taste attribute) M-CH and M-O treatments extended the shelf-life of chicken fillets by 6 days, while M-CH-O treatment resulted in a product with a shelf-life of 14 days, maintaining acceptable sensory characteristics.

  4. Sustained Release of Prindopril Erbumine from Its Chitosan-Coated Magnetic Nanoparticles for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Dena Dorniani

    2013-12-01

    Full Text Available The preparation of magnetic nanoparticles coated with chitosan-prindopril erbumine was accomplished and confirmed by X-ray diffraction, TEM, magnetic measurements, thermal analysis and infrared spectroscopic studies. X-ray diffraction and TEM results demonstrated that the magnetic nanoparticles were pure iron oxide phase, having a spherical shape with a mean diameter of 6 nm, compared to 15 nm after coating with chitosan-prindopril erbumine (FCPE. Fourier transform infrared spectroscopy study shows that the coating of iron oxide nanoparticles takes place due to the presence of some bands that were emerging after the coating process, which belong to the prindopril erbumine (PE. The thermal stability of the PE in an FCPE nanocomposite was remarkably enhanced. The release study showed that around 89% of PE could be released within about 93 hours by a phosphate buffer solution at pH 7.4, which was found to be of sustained manner governed by first order kinetic. Compared to the control (untreated, cell viability study in 3T3 cells at 72 h post exposure to both the nanoparticles and the pure drug was found to be sustained above 80% using different doses.

  5. Construction and Characterization of Coated Wire Oxalate Ion Selective Electrode Based on Chitosan

    Directory of Open Access Journals (Sweden)

    Zuri Rismiarti

    2013-10-01

    Full Text Available PVC (polyvinyl chloride membrane based coated wire oxalate ion selective electrode has been developed by using chitosan. The results showed the optimum composition of the membrane was chitosan: aliquat 336: PVC: DBP = 4:1:33:62 (% weight. The electrode showed Nernstian response, Nernst factor 29.90 mV/decade of concentration, linier concentration range of 1x10-5 - 1x10-1 M, detection limit of 2.56 x10-6 M, response time of 30 second, and life time of 42 days. ISE’s performance worked well in pH range of 5-7 and temperature of 25-50 oC. Validation test showed no significant difference (t test with the SSA method so that the potentiometric method could be used as an alternative method for determining urinary oxalate.

  6. Dyeing and printing wastewater treatment using fly-ash coated with chitosan

    Institute of Scientific and Technical Information of China (English)

    CHEN Xin; SUN Huili

    2009-01-01

    Printing and dyeing industry is a considerable source of environmental contamination. In this study treatment of printing and dyeing wastewater with a new type of sewage treatment agent, fly-ash coated with chitosan particles (FCCP), was examined. The effects of pH, stirring time, sedimentation time and temperature on color, COD, turbidity and NH_3-N removal were determined. The optimum dosage of FCCP and the influence of individual factors on removal efficiency were tested. The optimum parameters determined using the L_(16)(4~5) orthogonal experiment were as follows: FCCP (weight ratio of chitosan to fly-ash 1:6) dosage, 4 g·L~(-1); temperature, 35°C; pH, 4. The stirring time and sedimentation time were 20 min and 5 h, respectively. Under these optimum conditions, the color, COD and NH_3-N removal ratios were 97%, 80% and 75%, respectively.

  7. 2-Mercaptobenzothiazole doped chitosan/11-alkanethiolate acid composite coating: Dual function for copper protection

    Science.gov (United States)

    Bao, Qi; Zhang, Dun; Wan, Yi

    2011-10-01

    Chitosan (CS) hydrogel loaded with the well-known corrosion inhibitor 2-mercaptobenzothiazole (MBT) has been introduced into a composite coating to improve copper protection. This composite coating, which has both anticorrosion and antibacterial properties, was fabricated onto the surface of copper by combining a simple self-assembled monolayer technique with a sol-gel method. The anti-corrosion ability of the coating in 3.5 wt.% NaCl solution was investigated by electrochemical methods including potentiodynamic polarization and electrochemical impedance spectroscopy. The protection efficiency of the coating is 97.70%, calculated on the basis of the corrosion current density. The stability and integrity of the composite coating were evaluated by field emission scanning electron microscopy (FESEM) and energy dispersive spectrometry (EDS). The FESEM and EDS results suggest that the composite coating endows the copper substrate with antibacterial properties, as untreated bare copper underwent microbiologically influenced corrosion in the presence of sulphate reducing bacteria (SRB). This antibacterial feature was further confirmed by the SRB culture method. In a 3.5% NaCl solution and highly corrosive SRB culture media, the as-prepared CS based composite coating gave corrosion protection by exhibiting better barrier effects against the attack of aggressive environments.

  8. The Preparation of Capsaicin-Chitosan Microspheres (CCMS Enteric Coated Tablets

    Directory of Open Access Journals (Sweden)

    Jian Chen

    2013-12-01

    Full Text Available This study aimed to research the preparation and content determination of capsaicin-chitosan microspheres (CCMS enteric coated tablets. The core tablets were prepared with the method of wet granulation. Nine formulae were designed to determine the optimal formula of the core tablet. Eudragit L100 was used to prepare the CCMS enteric-coated tablets. The effect of enteric coated formulation variables such as content of talc (10%, 25% and 40%, plasticisers (TEC and DBS, dosage of plasticiser (10%, 20% and 30% and coating weight (2%, 3% and 5% were evaluated for drug release characteristics. The in vitro release was studied using 0.1 N HCl and pH 6.8 phosphate buffer. Enteric coated tablets without ruptures or swelling behaviour over 2 h in 0.1 N HCl indicated that these tablets showed acid resistance. The accumulated release rate in phosphate buffer (pH 6.8 revealed that the prepared tablets were able to sustain drug release into the intestine and a first-order release was obtained for capsaicin. This research is the first report of the preparation and content determination of CCMS enteric coated tablets. The sustained release behavior of enteric coated formulations in pH 6.8 phosphate buffer demonstrated that it would be a potential drug delivery platform for sustained delivery of gastric irritant drugs.

  9. Chitosan acetate as an active coating material and its effects on the storing of Prunus avium L.

    Science.gov (United States)

    Dang, Qi Feng; Yan, Jing Quan; Li, Yan; Cheng, Xiao Jie; Liu, Cheng Sheng; Chen, Xi Guang

    2010-03-01

    In this article, chitosan acetate (CA) was prepared by the method of solid-liquid reaction. CA was a stable faint yellow powder with water solubility. CA kept the same backbone in the chemical structure as the raw material of chitosan, and it also had the similar antibacterial properties with chitosan. CA could form a coating film on the outside surface of the sweet cherries, could effectively retard the loss of the water, titratable acidity, and ascorbic acid of sweet cherries, and could induce a significant increase in the peroxidase and catalase activities in the fruit. The CA coating could also increase the ratio of the total soluble solids and titratable acidity in the fruit. The application of CA effectively maintained quality attributes and extended postharvest life of the sweet cherries. The results revealed that the CA salts had potential application in active edible coating materials in the storage of fresh fruit.

  10. Biocompatibility behavior of β–tricalcium phosphate-chitosan coatings obtained on 316L stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Mina, A. [Tribology, Powder Metallurgy and Processing of Solid Recycled Research Group, Universidad del Valle, Cali (Colombia); Caicedo, H.H. [Department of Anatomy and Cell Biology, University of Illinois at Chicago, IL, 60612 (United States); National Biotechnology & Pharmaceutical Association, Chicago, IL, 60606 (United States); Uquillas, J.A. [Universidad San Francisco de Quito USFQ, Colegio de Ciencias de la Salud COCSA, Escuela de Medicina, Hospital de los Valles, Edificio de Especialidades Médicas, Av. Interoceánica km 12 1/2 Cumbayá, Quito (Ecuador); Biomaterials Innovation Research Center, Department of Medicine, Brigham and Women' s Hospital, Harvard Medical School, Boston, MA, 02139 (United States); Aperador, W. [Departament of Engineering, Universidad Militar Nueva Granada, Bogotá (Colombia); Gutiérrez, O. [Departament of Pharmacology Universidad del Valle, Cali (Colombia); Caicedo, J.C., E-mail: julio.cesar.caicedo@correounivalle.edu.co [Tribology, Powder Metallurgy and Processing of Solid Recycled Research Group, Universidad del Valle, Cali (Colombia)

    2016-06-01

    Biological interfaces involve the interaction of complex macromolecular systems and other biomolecules or biomaterials. Researchers have used a combination of cell, material sciences and engineering approaches to create functional biointerfaces to help improve biological functions. Materials such as hydroxyapatite (HA), β-tricalcium phosphate (β-TCP) and chitosan are important biomaterials to be used in biomedical applications such as bone-prosthesis interfaces. In this work, it was evaluated the effect of different concentrations of chitosan on the structural, electrochemical and biocompatible properties of β-tricalcium phosphate-chitosan ((β-Ca{sub 3}(PO{sub 4}){sub 2})-(C{sub 6}H{sub 11}NO{sub 4})n) hybrid coatings. β–tricalcium phosphate-chitosan coatings were deposited on 316L stainless steel substrates applying 260 mA AC, an agitation velocity of 250 rpm, and temperature deposition of 60 °C. It was possible to obtain coatings of 600 μm of thickness. Structure and surface properties were analyzed by X-ray diffraction (XRD) and dispersive X-ray analysis (EDX). It was found that the arrangement of the β-TCP crystal lattice changed with increasing chitosan weight concentration, showing that the orthorhombic structure of β-TCP is under tensile stress. The electrochemical properties of β–tricalcium phosphate/chitosan (β-TCP–Ch) coatings were analyzed by electrochemical impedance spectroscopy (EIS). Cellular biocompatibility was determined by lactate dehydrogenase (LDH) cytotoxicity assay using primary chinese hamster ovary (CHO) cells. β-TCP–Ch coatings with chitosan concentrations up to 25% caused cytotoxic effects to only 5–10% of CHO cells. Obtained results showed the influence of chitosan in the structural, electrochemical, and biocompatible properties of AISI 316L Stainless Steel. Consequently, the electrochemical and cytotoxic behavior of β-TCP–Ch on 316L Stainless Steel indicated that the coatings might be a promising material in

  11. Single-step electrochemical deposition of antimicrobial orthopaedic coatings based on a bioactive glass/chitosan/nano-silver composite system.

    Science.gov (United States)

    Pishbin, F; Mouriño, V; Gilchrist, J B; McComb, D W; Kreppel, S; Salih, V; Ryan, M P; Boccaccini, A R

    2013-07-01

    Composite orthopaedic coatings with antibacterial capability containing chitosan, Bioglass® particles (9.8μm) and silver nanoparticles (Ag-np) were fabricated using a single-step electrophoretic deposition (EPD) technique, and their structural and preliminary in vitro bactericidal and cellular properties were investigated. Stainless steel 316 was used as a standard metallic orthopaedic substrate. The coatings were compared with EPD coatings of chitosan and chitosan/Bioglass®. The ability of chitosan as both a complexing and stabilizing agent was utilized to form uniformly deposited Ag-np. Due to the presence of Bioglass® particles, the coatings were bioactive in terms of forming carbonated hydroxyapatite in simulated body fluid (SBF). Less than 7wt.% of the incorporated silver was released over the course of 28days in SBF and the possibility of manipulating the release rate by varying the deposition order of coating layers was shown. The low released concentration of Ag ions (effects. This was attributed to the relatively high concentration of Ag-np incorporated in the coatings.

  12. Optimization of preparation of chitosan-coated iron oxide nanoparticles for biomedical applications by chemometrics approaches

    Science.gov (United States)

    Honary, Soheila; Ebrahimi, Pouneh; Rad, Hossein Asgari; Asgari, Mahsa

    2013-08-01

    Functionalized magnetic nanoparticles are used in several biomedical applications, such as drug delivery, magnetic cell separation, and magnetic resonance imaging. Size and surface properties of iron oxide nanoparticles are the two important factors which could dramatically affect the nanoparticle efficiency as well as their stability. In this study, the chemometrics approach was applied to optimize the coating process of iron oxide nanoparticles. To optimize the size of nanoparticles, the effect of two experimental parameters on size was investigated by means of multivariate analysis. The factors considered were chitosan molecular weight and chitosan-to-tripolyphosphate concentration ratio. The experiments were performed according to face-centered cube central composite response surface design. A second-order regression model was obtained which characterized by both descriptive and predictive abilities. The method was optimized with respect to the percent of Z average diameter's increasing after coating as response. It can be concluded that experimental design provides a suitable means of optimizing and testing the robustness of iron oxide nanoparticle coating method.

  13. Preparation of silver-chitosan nanocomposites and coating on bandage for antibacterial wound dressing application

    Energy Technology Data Exchange (ETDEWEB)

    Susilowati, Endang, E-mail: endwati@yahoo.co.id; Ashadi [Chemistry Education Department, Faculty of Teacher Training and Education, Universitas Sebelas Maret Surakarta (Indonesia); Maryani [Medical Doctor Program, Faculty of Medicine, Universitas Sebelas Maret Surakarta, Indonesia Jl. Ir Sutami 36 A Surakarta Indonesia 53126 (Indonesia)

    2016-02-08

    Bandage is a medical device that is essential for wound dressing. To improve the performance of the bandage, it has been coated by silver-chitosan nanocomposites (Ag/Chit) with pad-dry-cure method. The nanocomposites were performed by chemical reduction method at room temperature using glucose as reducing agent, sodium hydroxide (NaOH) as accelerator reagent, silver nitrate (AgNO{sub 3}) as metal precursor and chitosan as stabilizing agent. Localized surface plasmon resonance (LSPR) absorption band of silver nanoparticles was investigated using UV-Vis spectrophotometer. The bandage coated Ag/Chit nanocomposites (B-Ag/Chit) were characterized by fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscope (SEM). In addition, antibacterial activity of the bandage toward Gram positive (Staphylococcus aureus) and Gram negative (Escherichia coli) were also studied. The formation of silver nanoparticles was confirmed by the appearance of LSPR absorption peak at 412.2 – 423.2 nm. Coating of nanocomposite cause increasing rigidity of bandage and decreasing on crystallinity. The bandages of B-Ag/Chit demonstrated good activity against both Gram positive (S. aureus) and Gram negative (E.Coli). Thus the bandages have a potential to be used for antibacterial wound dressing application.

  14. Novel chitosan/diclofenac coatings on medical grade stainless steel for hip replacement applications

    Science.gov (United States)

    Finšgar, Matjaž; Uzunalić, Amra Perva; Stergar, Janja; Gradišnik, Lidija; Maver, Uroš

    2016-05-01

    Corrosion resistance, biocompatibility, improved osteointegration, as well the prevention of inflammation and pain are the most desired characteristics of hip replacement implants. In this study we introduce a novel multi-layered coating on AISI 316LVM stainless steel that shows promise with regard to all mentioned characteristics. The coating is prepared from alternating layers of the biocompatible polysaccharide chitosan and the non-steroid anti-inflammatory drug (NSAID), diclofenac. Electrochemical methods were employed to characterize the corrosion behavior of coated and uncoated samples in physiological solution. It is shown that these coatings improve corrosion resistance. It was also found that these coatings release the incorporated drug in controlled, multi-mechanism manner. Adding additional layers on top of the as-prepared samples, has potential for further tailoring of the release profile and increasing the drug dose. Biocompatibility was proven on human-derived osteoblasts in several experiments. Only viable cells were found on the sample surface after incubation of the samples with the same cell line. This novel coating could prove important for prolongation of the application potential of steel-based hip replacements, which are these days often replaced by more expensive ceramic or other metal alloys.

  15. Prosopis alba exudate gum as excipient for improving fish oil stability in alginate-chitosan beads.

    Science.gov (United States)

    Vasile, Franco Emanuel; Romero, Ana María; Judis, María Alicia; Mazzobre, María Florencia

    2016-01-01

    The aim of the present work was to employ an exudate gum obtained from a South American wild tree (Prosopis alba), as wall material component to enhance the oxidative stability of fish oil encapsulated in alginate-chitosan beads. For this purpose, beads were vacuum-dried and stored under controlled conditions. Oxidation products, fatty acid profiles and lipid health indices were measured during storage. Alginate-chitosan interactions and the effect of gum were manifested in the FT-IR spectra. The inclusion of the gum in the gelation media allowed decreasing the oxidative damage during storage in comparison to the free oil and alginate-chitosan beads. The gum also improved wall material properties, providing higher oil retention during the drying step and subsequent storage. Fatty acids quality and lipid health indices were widely preserved in beads containing the gum. Present results showed a positive influence of the gum on oil encapsulation and stability, being the main mechanism attributed to a physical barrier effect.

  16. Chitosan-coated anisotropic silver nanoparticles as a SERS substrate for single-molecule detection

    Science.gov (United States)

    Potara, Monica; Baia, Monica; Farcau, Cosmin; Astilean, Simion

    2012-02-01

    Surface-enhanced Raman spectroscopy (SERS) is a technique that has become widely used for identifying and providing structural information about molecular species in low concentration. There is an ongoing interest in finding optimum particle size, shape and spatial distribution for optimizing the SERS substrates and pushing the sensitivity toward the single-molecule detection limit. This work reports the design of a novel, biocompatible SERS substrate based on small clusters of anisotropic silver nanoparticles embedded in a film of chitosan biopolymer. The SERS efficiency of the biocompatible film is assessed by employing Raman imaging and spectroscopy of adenine, a significant biological molecule. By combining atomic force microscopy with SERS imaging we find that the chitosan matrix enables the formation of small clusters of silver nanoparticles, with junctions and gaps that greatly enhance the Raman intensities of the adsorbed molecules. The study demonstrates that chitosan-coated anisotropic silver nanoparticle clusters are sensitive enough to be implemented as effective plasmonic substrates for SERS detection of nonresonant analytes at the single-molecule level.

  17. In vitro release and biological activities of Carum copticum essential oil (CEO) loaded chitosan nanoparticles.

    Science.gov (United States)

    Esmaeili, Akbar; Asgari, Azadeh

    2015-11-01

    In recent years, the unparalleled and functional properties of essential oils have been extensively reported, but the sensitivity of essential oils to environmental factors and their poor aqueous solubility have limited their applications in industries. Hence, we encapsulated CEO in chitosan nanoparticles by an emulsion-ionic gelation with pantasodium tripolyphosphate (TPP) and sodium hexametaphosphte (HMP), separately, as crosslinkers. The nanoparticles were analyzed by Fourier transform infrared spectroscopy (FT-IR), Ultraviolet-visible spectroscopy (UV-vis), differential scanning calorimetry (DSC), scanning electron microscope (SEM) and dynamic light scattering (DLS). The encapsulation efficiency (EE) and loading capacity (LC) of CEO in chitosan nanoparticles increased with the increase of initial CEO amount. The nanoparticles displayed an average size of 30-80nm with a spherical shape and regular distribution. In vitro release profiles exhibited an initial burst release and followed by a sustained CEO release at different pH conditions. The amount of CEO release from chitosan nanoparticles was higher in acidic pH to basic or neutral pH, respectively. The biological properties of CEO, before and after the encapsulation process were evaluated by 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and agar disk diffusion method, respectively. The results indicated the encapsulation of CEO in chitosan nanoparticles could be protected the quality.

  18. Isocyanate-Functionalized Chitin and Chitosan as Gelling Agents of Castor Oil

    Directory of Open Access Journals (Sweden)

    José M. Franco

    2013-06-01

    Full Text Available The main objective of this work was the incorporation of reactive isocyanate groups into chitin and chitosan in order to effectively use the products as reactive thickening agents in castor oil. The resulting gel-like dispersions could be potentially used as biodegradable lubricating greases. Three different NCO–functionalized polymers were obtained: two of them by promoting the reaction of chitosan with 1,6-hexamethylene diisocyanate (HMDI, and the other by using chitin instead of chitosan. These polymers were characterized through 1H-NMR, FTIR and thermogravimetric analysis (TGA. Thermal and rheological behaviours of the oleogels prepared by dispersing these polymers in castor oil were studied by means of TGA and small-amplitude oscillatory shear (SAOS measurements. The evolution and values of the linear viscoelasticity functions with frequency for –NCO–functionalized chitosan- and chitin-based oleogels are quite similar to those found for standard lubricating greases. In relation to long-term stability of these oleogels, no phase separation was observed and the values of viscoelastic functions increase significantly during the first seven days of ageing, and then remain almost constant. TGA analysis showed that the degradation temperature of the resulting oleogels is higher than that found for traditional lubricating greases.

  19. Isocyanate-functionalized chitin and chitosan as gelling agents of castor oil.

    Science.gov (United States)

    Gallego, Rocío; Arteaga, Jesús F; Valencia, Concepción; Franco, José M

    2013-06-03

    The main objective of this work was the incorporation of reactive isocyanate groups into chitin and chitosan in order to effectively use the products as reactive thickening agents in castor oil. The resulting gel-like dispersions could be potentially used as biodegradable lubricating greases. Three different NCO-functionalized polymers were obtained: two of them by promoting the reaction of chitosan with 1,6-hexamethylene diisocyanate (HMDI), and the other by using chitin instead of chitosan. These polymers were characterized through 1H-NMR, FTIR and thermogravimetric analysis (TGA). Thermal and rheological behaviours of the oleogels prepared by dispersing these polymers in castor oil were studied by means of TGA and small-amplitude oscillatory shear (SAOS) measurements. The evolution and values of the linear viscoelasticity functions with frequency for -NCO-functionalized chitosan- and chitin-based oleogels are quite similar to those found for standard lubricating greases. In relation to long-term stability of these oleogels, no phase separation was observed and the values of viscoelastic functions increase significantly during the first seven days of ageing, and then remain almost constant. TGA analysis showed that the degradation temperature of the resulting oleogels is higher than that found for traditional lubricating greases.

  20. Development of chitosan nanoparticles coated with hyaluronic acid for topical ocular delivery of dexamethasone.

    Science.gov (United States)

    Kalam, Mohd Abul

    2016-08-01

    The present study involved design of dexamethasone-sodium phosphate (DEX) loaded mucoadhesive chitosan nanoparticles for topical ocular delivery to improve its precorneal retention and corneal permeability. The chitosan-sodium tripolyphosphate nanoparticle (CS-NPs) was developed through ionotropic-gelation technique. The developed CS-NPs were coated with hyaluronic-acid (HA) to make discrete, free-flowing NPs and to improve their mucoadhesive characteristics. The particle-size, zeta-potential and polydispersity-index were determined by Malvern-Zetasizer. The average size of the CS-NPs ranged from 305.25±14.29nm (without HA-coating and before freeze-drying) to 400.57±15.23nm (HA-coated and after freeze-drying). Due to the polyanionic nature of HA, reversing of zeta-potentials from +32.55±4.15 to -33.74±3.45 was observed. Polydispersity-indices varied from 0.178±0.067 (before freeze-drying of HA-coated F2) to 0.427±0.028 (after freeze-drying of HA-coated F2). The encapsulation and loading capacity of around 72.95% and 14.51% respectively were found in optimized CS-NPs. In simulated tear fluid 75.84% cumulative amount of released drug was detected and the in-vitro release results suggested the mechanism of drug release was Fickian-diffusion type. The clarity, pH, refractive index, surface tension and viscosity of the suspensions of DEX-CS-NPs were found promising for ocular use. Stability study on nanoparticles revealed no significant changes were observed in particle-size, encapsulation, drug release and physicochemical characteristics at 25°C for 3-months storage.

  1. Electrophoretic deposition of chitosan/45S5 bioactive glass composite coatings doped with Zn and Sr

    Directory of Open Access Journals (Sweden)

    Marta eMiola

    2015-10-01

    Full Text Available In this research work the original 45S5 bioactive glass (BG was modified by introducing zinc and/or strontium oxide (6% mol in place of calcium oxide. Sr was added for its ability to stimulate bone formation, Zn for its role in bone metabolism, antibacterial properties and anti-inflammatory effect. The glasses were produced by means of melting and quenching process. SEM and XRD analyses evidenced that Zr and Sr introduction did not modify the glass structure and morphology, while compositional analysis (EDS demonstrated the effective addition of these elements inside the glass network. Bioactivity test in simulated body fluid (SBF up to one month evidenced a reduced bioactivity kinetics for Zn-doped glasses. Doped glasses were combined with chitosan to produce organic/inorganic composite coatings on stainless steel AISI 316L by electrophoretic deposition (EPD. Two EPD processes were considered for coating development, namely direct current EPD (DC-EPD and alternating current EPD (AC-EPD. The stability of the suspension was analysed and the deposition parameters were optimized. Tape and bending tests demonstrated a good coating-substrate adhesion for coatings containing 45S5-Sr and 45S5-ZnSr glasses, while the adhesion to the substrate decreased by using 45S5-Zn glass. FTIR analyses demonstrated the composite nature of coatings and SEM observations indicated that glass particles were well integrated in the polymeric matrix, the coatings were fairly homogeneous and free of cracks; moreover the AC-EPD technique provided better results than DC-EPD in terms of coating quality. SEM, XRD analyses and Raman spectroscopy, performed after bioactivity test in SBF solution, confirmed the bioactive behaviour of 45S5-Sr containing coating, while coatings containing Zn exhibited no hydroxyapatite formation.

  2. Electrophoretic Deposition of Chitosan/45S5 Bioactive Glass Composite Coatings Doped with Zn and Sr.

    Science.gov (United States)

    Miola, Marta; Verné, Enrica; Ciraldo, Francesca Elisa; Cordero-Arias, Luis; Boccaccini, Aldo R

    2015-01-01

    In this research work, the original 45S5 bioactive glass was modified by introducing zinc and/or strontium oxide (6 mol%) in place of calcium oxide. Sr was added for its ability to stimulate bone formation and Zn for its role in bone metabolism, antibacterial properties, and anti-inflammatory effect. The glasses were produced by means of melting and quenching process. SEM and XRD analyses evidenced that Zr and Sr introduction did not modify the glass structure and morphology while compositional analysis (EDS) demonstrated the effective incorporation of these elements in the glass network. Bioactivity test in simulated body fluid (SBF) up to 1 month evidenced a reduced bioactivity kinetics for Zn-doped glasses. Doped glasses were combined with chitosan to produce organic/inorganic composite coatings on stainless steel AISI 316L by electrophoretic deposition (EPD). Two EPD processes were considered for coating development, namely direct current EPD (DC-EPD) and alternating current EPD (AC-EPD). The stability of the suspension was analyzed and the deposition parameters were optimized. Tape and bending tests demonstrated a good coating-substrate adhesion for coatings containing 45S5-Sr and 45S5-ZnSr glasses, whereas the adhesion to the substrate decreased by using 45S5-Zn glass. FTIR analyses demonstrated the composite nature of coatings and SEM observations indicated that glass particles were well integrated in the polymeric matrix, the coatings were fairly homogeneous and free of cracks; moreover, the AC-EPD technique provided better results than DC-EPD in terms of coating quality. SEM, XRD analyses, and Raman spectroscopy, performed after bioactivity test in SBF solution, confirmed the bioactive behavior of 45S5-Sr-containing coating while coatings containing Zn exhibited no hydroxyapatite formation.

  3. Comparison on mechanical properties of single layered and bilayered chitosan-gelatin coated porous hydroxyapatite scaffold prepared through freeze drying method

    Science.gov (United States)

    Effendi, M. D.; Gustiono, D.; Lukmana; Ayu, D.; Kurniawati, F.

    2017-02-01

    Biopolymer coated porous hydroxyapatite (HA) scaffolds were prepared for tissue engineering trough freeze drying method and impregnation. in this study, to mimic the mineral and organic component of natural bone, synthetic hydroxapatite (HA) scaffolds coated by polymer were prepared. Highly porous Hap scaffolds, fabricated by synthetic HA impregnation method on polyurethane foam, were coated with polymer coating solution, consisting of chitosan, Gelatin, and bilayered chitosan-gelatin prepared by aging and impregnating technique. For the purpose of comparison, The bare scaffolds without polymer coating layer were investigated. The Bare scaffolds were highly porous and interconnected with a pore size of around 150 µm–714 µm, has porosity at around 67,7% -85,7%, and has mechanical strength at around 0.06 Mpa - 0.071 Mpa, which is suitable for osteoblast cell Proliferation. Chitosan coated porous HA scaffold and gelatin coated porous HA scaffold had mechanical strength at around 0.81-0.85 Mpa, and 1.32-1.34 Mpa, respectively, with weight ratio of biopolymer and Hap was around 18%-22%. To compare these results, the coating on the bare scaffold with gelatin and chitosan had been conducted. Based on the result of FTIR, it could be concluded that coating procedure applied on porous hydroxy apatite (HA) coated by gelatin, chitosan coated HA scaffold, and bilayered Gelatin-chitosan coated porous HA scaffold, confirming that for allsampleshad no significant chemical effect on the coating structure. The compressive strength of bilayered Gelatin-chitosan coated HA scaffold had middle values between the rest, at around 1,06-1.2 Mpa for the samples at the same weight ratio of biopolymer: HA (around 18% - 22%). These results also confirming that coating by gelatin on porous hydroxyapatite was highest compresive strength and can be applied to improve mechanical properties of porous hydroxyapatite bare scaffold

  4. Electrophoretic deposition and characterization of HA/chitosan nanocomposite coatings on Ti6Al7Nb alloy

    Science.gov (United States)

    Moskalewicz, Tomasz; Kot, Marcin; Seuss, Sigrid; Kędzierska, Aleksandra; Czyrska-Filemonowicz, Aleksandra; Boccaccini, Aldo R.

    2015-01-01

    Nano-hydroxyapatite/chitosan (nc-HA/chitosan) composite coatings were produced on two phase (α+β) Ti6Al7Nb titanium alloy substrates by electrophoretic deposition (EPD). The microstructure of the coatings was examined by scanning- and transmission electron microscopy methods as well as by X-ray diffractometry. The coatings, 770 nm-800 nm thick, were uniform, without any cracks or presence of large voids and they exhibited good adhesion to the titanium alloy substrate. The microstructure of the coatings consisted of nc-HA needle-like particles homogeneously embedded in a chitosan matrix. The deposited coatings exhibited good adhesion to the substrate. The best adhesion to the titanium alloy was determined for the coating deposited from suspensions containing 4 g/L of HA at 10 V during 240 s. The results confirm EPD as a convenient method to develop uniform and crack-free nanoscale organic-inorganic composite coatings on two phase titanium alloy substrates with potential application in orthopedic and dental implants.

  5. Reduction of cytotoxicity of natural rubber latex film by coating with PMMA-chitosan nanoparticles.

    Science.gov (United States)

    Kanjanathaworn, Nuttakun; Polpanich, Duangporn; Jangpatarapongsa, Kulachart; Tangboriboonrat, Pramuan

    2013-08-14

    Poly(methyl methacrylate) (PMMA) latex stabilized by chitosan (CS) oligomer was synthesized via the miniemulsion polymerization. By using 1% CS solution (in 0.1M acetic acid), the spherical PMMA-CS particles with an average size of 380 nm were obtained. The positive zeta potentials at pH 2-7 confirmed the presence of CS as the outermost layer of the latex particles. Therefore, these particles directly interacted with the indigenous non-rubbers at the surface of sulphur prevulcanized natural rubber (SPNR) film. The deposition of PMMA-CS particles caused an increase in surface roughness of the coated SPNR film as a function of latex concentration and immersion time. The simple coating of the rubber substrate with PMMA-CS particles effectively reduced the in vitro cytotoxicity on L-929 cells. This study would be, therefore, helpful for development of latex gloves designed for hypersensitive users.

  6. Chitosan-coated mesoporous MIL-100(Fe) nanoparticles as improved bio-compatible oral nanocarriers

    Science.gov (United States)

    Hidalgo, T.; Giménez-Marqués, M.; Bellido, E.; Avila, J.; Asensio, M. C.; Salles, F.; Lozano, M. V.; Guillevic, M.; Simón-Vázquez, R.; González-Fernández, A.; Serre, C.; Alonso, M. J.; Horcajada, P.

    2017-01-01

    Nanometric biocompatible Metal-Organic Frameworks (nanoMOFs) are promising candidates for drug delivery. Up to now, most studies have targeted the intravenous route, related to pain and severe complications; whereas nanoMOFs for oral administration, a commonly used non-invasive and simpler route, remains however unexplored. We propose here the biofriendly preparation of a suitable oral nanocarrier based on the benchmarked biocompatible mesoporous iron(III) trimesate nanoparticles coated with the bioadhesive polysaccharide chitosan (CS). This method does not hamper the textural/structural properties and the sorption/release abilities of the nanoMOFs upon surface engineering. The interaction between the CS and the nanoparticles has been characterized through a combination of high resolution soft X-ray absorption and computing simulation, while the positive impact of the coating on the colloidal and chemical stability under oral simulated conditions is here demonstrated. Finally, the intestinal barrier bypass capability and biocompatibility of CS-coated nanoMOF have been assessed in vitro, leading to an increased intestinal permeability with respect to the non-coated material, maintaining an optimal biocompatibility. In conclusion, the preservation of the interesting physicochemical features of the CS-coated nanoMOF and their adapted colloidal stability and progressive biodegradation, together with their improved intestinal barrier bypass, make these nanoparticles a promising oral nanocarrier. PMID:28256600

  7. Chitosan-coated mesoporous MIL-100(Fe) nanoparticles as improved bio-compatible oral nanocarriers

    Science.gov (United States)

    Hidalgo, T.; Giménez-Marqués, M.; Bellido, E.; Avila, J.; Asensio, M. C.; Salles, F.; Lozano, M. V.; Guillevic, M.; Simón-Vázquez, R.; González-Fernández, A.; Serre, C.; Alonso, M. J.; Horcajada, P.

    2017-03-01

    Nanometric biocompatible Metal-Organic Frameworks (nanoMOFs) are promising candidates for drug delivery. Up to now, most studies have targeted the intravenous route, related to pain and severe complications; whereas nanoMOFs for oral administration, a commonly used non-invasive and simpler route, remains however unexplored. We propose here the biofriendly preparation of a suitable oral nanocarrier based on the benchmarked biocompatible mesoporous iron(III) trimesate nanoparticles coated with the bioadhesive polysaccharide chitosan (CS). This method does not hamper the textural/structural properties and the sorption/release abilities of the nanoMOFs upon surface engineering. The interaction between the CS and the nanoparticles has been characterized through a combination of high resolution soft X-ray absorption and computing simulation, while the positive impact of the coating on the colloidal and chemical stability under oral simulated conditions is here demonstrated. Finally, the intestinal barrier bypass capability and biocompatibility of CS-coated nanoMOF have been assessed in vitro, leading to an increased intestinal permeability with respect to the non-coated material, maintaining an optimal biocompatibility. In conclusion, the preservation of the interesting physicochemical features of the CS-coated nanoMOF and their adapted colloidal stability and progressive biodegradation, together with their improved intestinal barrier bypass, make these nanoparticles a promising oral nanocarrier.

  8. Inhibition of Listeria monocytogenes ATCC 19115 on ham steak by tea bioactive compounds incorporated into chitosan-coated plastic films

    Directory of Open Access Journals (Sweden)

    Vodnar Dan C

    2012-07-01

    Full Text Available Abstract Background The consumer demands for better quality and safety of food products have given rise to the development and implementation of edible films. The use of antimicrobial films can be a promising tool for controlling L. monocytogenes on ready to eat products. The aim of this study was to develop effective antimicrobial films incorporating bioactive compounds from green and black teas into chitosan, for controlling L. monocytogenes ATCC 19115 on vacuum-packaged ham steak. The effectiveness of these antimicrobial films was evaluated at room temperature (20°C for 10 days and at refrigerated temperature (4°C for 8 weeks. Results The HPLC results clearly show that relative concentrations of catechins and caffeine in green tea ranked EGCG>EGC>CAF>ECG>EC>C while in black tea extracts ranked CAF>EGCG>ECG>EGC>EC>C. The chitosan-coated plastic films incorporating green tea and black tea extracts shows specific markers identified by FTIR. Incorporating natural extracts into chitosan showed that the growth of L monocytogenes ATCC 19115 was inhibited. The efficacy of antimicrobial effect of tea extracts incorporated into chitosan-coated plastic film was dose dependent. However, chitosan-coated films without addition of tea extracts did not inhibit the growth of L. monocytogenes ATCC 19115. Chitosan-coated plastic films incorporating 4% Green tea extract was the most effective antimicrobial, reducing the initial counts from 3.2 to 2.65 log CFU/cm2 during room temperature storage and from 3.2 to 1–1.5 log CFU/cm2 during refrigerated storage. Conclusions Incorporation of tea extracts into the chitosan-coated films considerably enhanced their effectiveness against L. monocytogenes ATCC 19115. 4% Green tea incorporated into chitosan-coated plastic film had a better antilisterial effect than 2% green tea or 2% and 4% black tea. Data from this study would provide new formulation options for developing antimicrobial packaging films using tea

  9. Biodegradable gelatin-chitosan films incorporated with essential oils as antimicrobial agents for fish preservation.

    Science.gov (United States)

    Gómez-Estaca, J; López de Lacey, A; López-Caballero, M E; Gómez-Guillén, M C; Montero, P

    2010-10-01

    Essential oils of clove (Syzygium aromaticum L.), fennel (Foeniculum vulgare Miller), cypress (Cupressus sempervirens L.), lavender (Lavandula angustifolia), thyme (Thymus vulgaris L.), herb-of-the-cross (Verbena officinalis L.), pine (Pinus sylvestris) and rosemary (Rosmarinus officinalis) were tested for their antimicrobial activity on 18 genera of bacteria, which included some important food pathogen and spoilage bacteria. Clove essential oil showed the highest inhibitory effect, followed by rosemary and lavender. In an attempt to evaluate the usefulness of these essential oils as food preservatives, they were also tested on an extract made of fish, where clove and thyme essential oils were the most effective. Then, gelatin-chitosan-based edible films incorporated with clove essential oil were elaborated and their antimicrobial activity tested against six selected microorganisms: Pseudomonas fluorescens, Shewanella putrefaciens, Photobacterium phosphoreum, Listeria innocua, Escherichia coli and Lactobacillus acidophilus. The clove-containing films inhibited all these microorganisms irrespectively of the film matrix or type of microorganism. In a further experiment, when the complex gelatin-chitosan film incorporating clove essential oil was applied to fish during chilled storage, the growth of microorganisms was drastically reduced in gram-negative bacteria, especially enterobacteria, while lactic acid bacteria remained practically constant for much of the storage period. The effect on the microorganisms during this period was in accordance with biochemical indexes of quality, indicating the viability of these films for fish preservation.

  10. Characterization of antimicrobial properties on the growth of S. aureus of novel renewable blends of gliadins and chitosan of interest in food packaging and coating applications.

    Science.gov (United States)

    Fernandez-Saiz, P; Lagaron, J M; Hernandez-Muñoz, P; Ocio, M J

    2008-05-10

    The biocide properties of chitosan-based materials have been known for many years. However, typical antimicrobial formulations of chitosan, mostly chitosonium salts, are known to be very water sensitive materials which may impair their use in many application fields such as food packaging or food coating applications. This first work reports on the development and characterization of the antimicrobial properties of novel fully renewable blends of chitosan with more water-resistant gliadin proteins isolated from wheat gluten. Chitosan release to the nutrient broth from a wide range of blends was studied making use of the ninhydrin method. The results indicated that both pure chitosan and its blends with gliadins presented significant antimicrobial activity, which increased with increasing the amount of chitosan in the composite formulation as expected. The gliadins-chitosan blends showed good transparency and film-forming properties and better water resistance than pure chitosan. The release tests revealed that dissolution of the biocide glucosamine groups, i.e. the chitosan water soluble fractions, also increased with the amount of chitosan present in the formulation. The release of these groups was for the first time directly correlated with the antimicrobial properties exhibited by the blends. Thus, incorporation of chitosan into an insoluble biopolymer matrix was revealed as a very feasible strategy to generate novel chitosan-based antimicrobial materials with potential advantages, for instance active food packaging applications.

  11. Chitosan microencapsulation of various essential oils to enhance the functional properties of cotton fabric.

    Science.gov (United States)

    Javid, Amjed; Raza, Zulfiqar Ali; Hussain, Tanveer; Rehman, Asma

    2014-01-01

    The present study dealt with emulsive fabrication of chitosan microcapsules encapsulating essential oils in the present of bio/surfactant. The size distribution, morphology and stability of microcapsules were examined by using advanced surface characterisation techniques. At cetyl trimethyl ammonium bromide (CTAB) concentration of 330 mg/L, the smallest average size of microcapsules was observed as12.8 μm; whereas with biosurfactant at 50 mg/L, the microcapsules of smallest average size of 7.5 μm were observed. The fabricated microcapsules were applied on a desized, bleached and mercerised cotton fabric by using pad-dry-cure method by using a modified dihydroxy ethylene urea as a cross-linking agent. The cross-linking was confirmed by using scanning electron microscopy and Fourier transform infrared spectroscopy techniques. The antibacterial activity of finished fabric was evaluated using the turbidity estimation method. The stiffness and wrinkle recovery properties of the treated fabric were also investigated by using the standard methods. In general, antibacterial activity of treated fabric increased with the increase in chitosan and essential oil concentrations, whereas stiffness increased with increase in concentration of chitosan but decreased with increase in essential oil concentration.

  12. Enhancement of oil recovery using zirconium-chitosan hybrid composite by adsorptive method.

    Science.gov (United States)

    Elanchezhiyan, S Sd; Sivasurian, N; Meenakshi, Sankaran

    2016-07-10

    Recovery of oil from oil-in-water emulsion has been investigated by many scientists and it continues to be a challenging task for environmental scientists so far. Among all the techniques, adsorption is found to be an appropriate process for the removal of oil from oil-in-water emulsion owing to its high efficiency and easy operation. A hybrid material, zirconium-chitosan composite (Zr-CS-HC) was prepared to remove the oil from oil-in-water emulsion and oil was measured by extractive gravimetric method. Various parameters viz., agitation time, pH, sorbent dosage and initial oil concentration for maximum sorption were optimized. In this study, the maximum oil removal percentage was found to be at pH 3.0 and a minimum contact time of 50min using prepared sorbent. The pH of the sorption studies revealed that oil sorption was favored in acidic condition. The sorbent was characterized using FTIR, SEM with EDAX, XRD, TGA and DSC; contact angle and heat of combustion. The experimental data were explained using Freundlich, Langmuir, D-R and Tempkin isotherms to find the best fit for the sorption process. Thermodynamic parameters such as ΔG°, ΔH° and ΔS° were calculated to understand the nature of sorption process. This work provides a potential platform for the expansion of oil removal technology.

  13. Hepatitis B surface antigen nanoparticles coated with chitosan and trimethyl chitosan: Impact of formulation on physicochemical and immunological characteristics.

    Science.gov (United States)

    Tafaghodi, Mohsen; Saluja, Vinay; Kersten, Gideon F A; Kraan, Heleen; Slütter, Bram; Amorij, Jean-Pierre; Jiskoot, Wim

    2012-08-03

    Mucosal immunization offers various advantages over parenteral vaccination, but typically requires potent delivery systems and/or adjuvants to result in protective immunity. Here we report on the preparation of trimethylated chitosan (TMC) and chitosan (CHT) nanoparticles (NPs) loaded with hepatitis B surface antigen (HB), by a simple and scalable method. TMC:HB and CHT:HB NPs were prepared by direct coating of antigen by polymer. The impact of buffer, pH and tonicity of the dispersion medium on NPs' polydispersity, zeta potential and association percentage of polymer with antigen was evaluated. Moreover, biological properties of both NPs were addressed in vitro by studying their effect on cell viability, transepithelial electrical resistance (TEER) and dendritic cell (DC) maturation. Finally, immunogenicity was assessed by evaluating IgG, IgG1, IgG2a, IgA titers and sIgA after both mucosal (nasal) as well intramuscular (i.m.) vaccination in a murine model. TMC:HB and CHT:HB NPs, prepared in acetate buffer pH 6.7 of three different tonicities, had comparable size, polydispersity, zeta potential and association percentage. TMC:HB NPs, but not CHT:HB NPs, had a mild negative effect on cell viability and TEER, and a considerable positive effect on DC maturation. After nasal and i.m. immunization, TMC:HB NPs in hypotonic medium and CHT:HB NPs in all media induced higher serum and nasal antibody titers compared with HB solution (P<0.001). After i.m. injection, both TMC:HB and CHT:HB NPs induced higher IgG and IgG2a titers compared with alum adsorbed HB (P<0.001). For CHT:HB NPs, the tonicity of the dispersion medium did not affect the mucosal and systemic immune responses. In conclusion, TMC NPs and CHT NPs are similarly potent mucosal immunoadjuvants for HB. Moreover, both polymers are potent immunoadjuvants for i.m. administered isotonic HB, resulting in higher IgG2a/IgG1 ratios compared with alum adjuvanted HB.

  14. Solid lipid nanoparticles for oral drug delivery: chitosan coating improves stability, controlled delivery, mucoadhesion and cellular uptake.

    Science.gov (United States)

    Luo, Yangchao; Teng, Zi; Li, Ying; Wang, Qin

    2015-05-20

    The poor stability of solid lipid nanoparticles (SLN) under acidic condition resulted in large aggregation in gastric environment, limiting their application as oral delivery systems. In this study, a series of SLN was prepared to investigate the effects of surfactant/cosurfactant and chitosan coating on their physicochemical properties as well as cellular uptake. SLN was prepared from Compritol 888 ATO using a low-energy method combining the solvent-diffusion and hot homogenization technique. Poloxamer 188 and polyethylene glycol (PEG) were effective emulsifiers to produce SLN with better physicochemical properties than SLN control. Chitosan-coated SLN exhibited the best stability under acidic condition by forming a thick layer around the lipid core, as clearly observed by transmission electron microscope. The intermolecular interactions in different formulations were monitored by Fourier transform infrared spectroscopy. Chitosan coating also significantly improved the mucoadhesive property of SLN as determined by Quartz Crystal Microbalance. In vitro drug delivery assays, cytotoxicity, and cellular uptake of SLN were studied by incorporating coumarin 6 as a fluorescence probe. Overall, chitosan-coated SLN was superior to other formulations and held promising features for its application as a potential oral drug delivery system for hydrophobic drugs.

  15. Preparation of H-oleoyl-carboxymethyl-chitosan and the function as a coagulation agent for residual oil in aqueous system

    Institute of Scientific and Technical Information of China (English)

    Gang-zheng SUN; Xi-guang CHEN; Yan-yan LI; Bo ZHENG; Zheng-hui GONG; Jian-jun SUN; Heng CHEN; Jie LI; Wen-xing LIN

    2008-01-01

    In this study, H-form oleoyl-carboxymethyl-chitosan (H-O-CMCS) was prepared as a coagulation agent to clean up the residual oil from the waste-water of oil extraction (WWOE). The Fourier transform infra-red (FTIR) spectra confirmed the formation of an amide linkage between amino groups of carboxymethyl chitosan (CMCS) and carboxyl groups of oleic acid. The adsorp-tion capacities of four absorbents (H-O-CMCS, chitosan, activated carbon and polyaluminium chloride (PAC)) for the residual oil were investigated. Compared with chit-osan, activated carbon and PAC, H-O-CMCS was more effective in removing the residual oil from WWOE, which could successfully wash up almost 99% of residual oil from WWOE at the dosage of 0.2 g/L, the mixing time of 3 min, 500 rpm, and a broader range of pH (the system temperature ≤ 45℃). In similar conditions, com-paratively, chitosan, activated carbon and PAC could wash 90%, 82% and 92% of residual oil from WWOE, respectively.

  16. Hyaluronic acid-coated chitosan nanoparticles: molecular weight-dependent effects on morphology and hyaluronic acid presentation.

    Science.gov (United States)

    Almalik, Abdulaziz; Donno, Roberto; Cadman, Christopher J; Cellesi, Francesco; Day, Philip J; Tirelli, Nicola

    2013-12-28

    Chitosan nanoparticles are popular carriers for the delivery of macromolecular payloads, e.g. nucleic acids. In this study, nanoparticles were prepared via complexation with triphosphate (TPP) anions and were successively coated with hyaluronic acid (HA). Key variables of the preparative process (e.g. chitosan and HA molecular weight) were optimised in view of the maximisation of loading with DNA, of the Zeta potential and of the dimensional stability, and the resulting particles showed excellent storage stability. We have focused on the influence of chitosan molecular weight on nanoparticle properties. Larger molecular weight increased their porosity (=decreased cross-link density), and this caused also larger dimensional changes in response to variations in osmotic pressure or upon drying. The dependency of nanoparticle porosity on chitosan molecular weight had a profound effect on the adsorption of HA on the nanoparticles; HA was apparently able to penetrate deeply into the more porous high molecular weight (684 kDa) chitosan nanoparticles, while it formed a corona around those composed of more densely cross-linked low molecular weight (25 kDa) chitosan. Atomic Force Microscopy (AFM) allowed not only to highlight the presence of this corona, but also to estimate its apparent thickness to about 20-30 nm (in a dry state). The different morphology has a significant effect on the way HA is presented to biomolecules, and this has specific relevance in relation to interactions with HA receptors (e.g. CD44) that influence kinetics and mechanism of nanoparticle uptake. Finally, it is worth to mention that chitosan molecular weight did not appear to greatly affect the efficiency of nanoparticle loading with DNA, but significantly influenced its chitosanase-triggered release, with high molecular chitosan nanoparticles seemingly more prone to degradation by this enzyme.

  17. Formulation of sage essential oil (Salvia officinalis, L.) monoterpenes into chitosan hydrogels and permeation study with GC-MS analysis.

    Science.gov (United States)

    Kodadová, Alexandra; Vitková, Zuzana; Herdová, Petra; Ťažký, Anton; Oremusová, Jarmila; Grančai, Daniel; Mikuš, Peter

    2015-01-01

    This study deals with the formulation of natural drugs into hydrogels. For the first time, compounds from the sage essential oil were formulated into chitosan hydrogels. A sample preparation procedure for hydrophobic volatile analytes present in a hydrophilic water matrix along with an analytical method based on the gas chromatography coupled with the mass spectrometry (GC-MS) was developed and applied for the evaluation of the identity and quantity of essential oil components in the hydrogels and saline samples. The experimental results revealed that the chitosan hydrogels are suitable for the formulation of sage essential oil. The monoterpene release can be effectively controlled by both chitosan and caffeine concentration in the hydrogels. Permeation experiment, based on a hydrogel with the optimized composition [3.5% (w/w) sage essential oil, 2.0% (w/w) caffeine, 2.5% (w/w) chitosan and 0.1% (w/w) Tween-80] in donor compartment, saline solution in acceptor compartment, and semi-permeable cellophane membrane, demonstrated the useful permeation selectivity. Here, (according to lipophilicity) an enhanced permeation of the bicyclic monoterpenes with antiflogistic and antiseptic properties (eucalyptol, camphor and borneol) and, at the same time, suppressed permeation of toxic thujone (not exceeding its permitted applicable concentration) was observed. These properties highlight the pharmaceutical importance of the developed chitosan hydrogel formulating sage essential oil in the dermal applications.

  18. The Effect of Chitosan on Organogenesis of Oil Palm Embryo-Derived Callus

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    Kantamaht KANCHANAPOOM

    2010-06-01

    Full Text Available Zygotic embryos of oil palm (Elaeis guineensis Jacq. var. tenera were excised and cultured on MS medium containing 3 mg/l 2, 4-D either with or without 0.05% activated charcoal (AC. Improved growth of embryos was obtained on MS medium supplemented with 0.05% AC. Callus cultures were initiated from embryos, young leaves and roots on MS medium containing 2, 4-D, NAA and 0.05% AC. On these media, two morphologically distinct types of white and yellow compact calluses were produced. Green shoots regenerated after several transfers of the yellow compact calluses from zygotic embryos to MS medium supplemented with 15 mg/l chitosan either with or without 5 mg/l 2, 4-D. Histological sectioning revealed that regenerated shoots originated from a clump of meristematic cells that had dense cytoplasm. Regenerated shoots rooted when transferred to MS medium in the presence of 0.05% AC. Transfer of plantlets to soil was achieved. Callus from young seedling leaves and roots did not regenerate shoots or roots in medium containing 2, 4-D or TDZ, with or without chitosan. This finding shows that chitosan can initiate organogenesis in oil palm callus.

  19. Chemical treatment and chitosan coating of yeast cells to improve the encapsulation and controlled release of bovine serum albumin.

    Science.gov (United States)

    Shi, Guorong; Liu, Yating; He, Zijun; Zhou, Jihen

    2016-08-10

    We investigate the encapsulation of bovine serum albumin (BSA) in chemical-treated and chitosan-coated yeast cells, Saccharomyces cerevisiae (S. cerevisiae), for the controlled release of BSA. The chemical treatment can sufficiently enlarge the small-sized cell-wall cavities and/or break the integrity for the entrance of BSA to the interior of yeast cells, and the additional chitosan coating can well prevent the rapid release of encapsulated BSA from the yeast-derived microcapsules. The sodium hydroxide pretreated S. cerevisiae gives a maximum encapsulation yield of (10.1 ± 0.2)% for BSA. An additional coating of S. cerevisiae with chitosan can reduce the initial burst release of BSA and extend the release period from 24 h in the chitosan-free case to 48 h in phosphate buffer at pH 7.4. The prepared microcapsules can well keep the shapes and sizes of yeast cells and thus show uniform sizes of 3.85 ± 0.81 μm. The encapsulated BSA well retains its pristine ultraviolet spectroscopic and chromatographic behaviors. The present microencapsulation protocol has the advantages of convenient and mild operation, high encapsulation efficiency, and organic solvent-free nature, which is of reference value for establishing high-performance controllable biomacromolecule-delivery systems.

  20. A coating of chitosan and propolis extract for the postharvest treatment of papaya (Carica papaya L. cv. Hawaiiana

    Directory of Open Access Journals (Sweden)

    Elizabeth Barrera

    2015-06-01

    Full Text Available Propolis is a natural antimicrobial that can be used asa bioadditive in coatings to control fruit quality losses. The effectof two coatings was evaluated, a control (chitosan, 1% and atreatment (chitosan, 1%; containing propolisethanolic extract, 5%,on the microbiological and physicochemical properties of papayafruits. The chemical profile of the propolis revealed the presenceof fatty acids and their esters, carbohydrates, diterpenic acids,and pentacyclic triterpenes. The fruits covered with the treatmentdemonstrated a reduced deterioration index and infection diameterof the fungus Colletotrichum gloeosporioides, as compared tothe control papayas, postponing the appearance of damage bytwo days. Additionally, the treatment did not significantly affectthe physicochemical properties of the papaya, as compared tothe control. In conclusion, the coating formulated with propolisexhibited an in situ fungicidal and bactericidal effect withoutaltering the physiological changes of the papaya fruit duringstorage.

  1. Bacterial inhibition potential of quaternised chitosan-coated VICRYL absorbable suture: An in vitro and in vivo study

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    Ying Yang

    2017-01-01

    Conclusion: In general, the present study demonstrated that the quaternised chitosan coating is a flexible and cost-effective alternative strategy to prevent the suture related surgical site infections in orthopaedic practices.

  2. Surface modification of orthodontic implants by nanocomposite coatings based on chitosan and metals

    Directory of Open Access Journals (Sweden)

    Suetenkov D.Ye.

    2013-09-01

    Full Text Available Purpose: to study the properties of nanostructured coatings in orthodontic implants. Material and methods. Low and average molecular mass chitosan, 3-amynopropil-3-methoxysylan and suspensions of 5 nm and 10 nm gold nano-spheres stabilized with natrium citrate were used for nanocomposed surfaces. 2mg/ml polyethylenamin water solution was used for making the underlayer before putting polyion coverage using «POLYION-1M». The polyion covering dynamics was studied by polyquartz weighing method. Morphology of created layers was studied with atomic microscopy, elements were studied by secondary ion mass-spectrometry. Results. The best transmission among structures of chito-san/metals was showed by low molecular mass of chitosan and 8-1 Onm nanoparticles of metals. Analysis of roughness of surface shows that nanoparticles of gold make the most solid surface on 3-amynopropil-3-methoxysylan underlayer. Conclusion. The development of biocomparative materials in maxillofacial surgery is considered to be effective method of decreasing the risk of post-operative inflammatory complications by local antibacterial effect.

  3. Fluorescence Modified Chitosan-Coated Magnetic Nanoparticles for High-Efficient Cellular Imaging

    Directory of Open Access Journals (Sweden)

    Nie Fang

    2009-01-01

    Full Text Available Abstract Labeling of cells with nanoparticles for living detection is of interest to various biomedical applications. In this study, novel fluorescent/magnetic nanoparticles were prepared and used in high-efficient cellular imaging. The nanoparticles coated with the modified chitosan possessed a magnetic oxide core and a covalently attached fluorescent dye. We evaluated the feasibility and efficiency in labeling cancer cells (SMMC-7721 with the nanoparticles. The nanoparticles exhibited a high affinity to cells, which was demonstrated by flow cytometry and magnetic resonance imaging. The results showed that cell-labeling efficiency of the nanoparticles was dependent on the incubation time and nanoparticles’ concentration. The minimum detected number of labeled cells was around 104by using a clinical 1.5-T MRI imager. Fluorescence and transmission electron microscopy instruments were used to monitor the localization patterns of the magnetic nanoparticles in cells. These new magneto-fluorescent nanoagents have demonstrated the potential for future medical use.

  4. Cellulases immobilization on chitosan-coated magnetic nanoparticles: application for Agave Atrovirens lignocellulosic biomass hydrolysis.

    Science.gov (United States)

    Sánchez-Ramírez, Jaquelina; Martínez-Hernández, José L; Segura-Ceniceros, Patricia; López, Guillermo; Saade, Hened; Medina-Morales, Miguel A; Ramos-González, Rodolfo; Aguilar, Cristóbal N; Ilyina, Anna

    2017-01-01

    In the present study, Trichoderma reesei cellulase was covalently immobilized on chitosan-coated magnetic nanoparticles using glutaraldehyde as a coupling agent. The average diameter of magnetic nanoparticles before and after enzyme immobilization was about 8 and 10 nm, respectively. The immobilized enzyme retained about 37 % of its initial activity, and also showed better thermal and storage stability than free enzyme. Immobilized cellulase retained about 80 % of its activity after 15 cycles of carboxymethylcellulose hydrolysis and was easily separated with the application of an external magnetic field. However, in this reaction, K m was increased eight times. The immobilized enzyme was able to hydrolyze lignocellulosic material from Agave atrovirens leaves with yield close to the amount detected with free enzyme and it was re-used in vegetal material conversion up to four cycles with 50 % of activity decrease. This provides an opportunity to reduce the enzyme consumption during lignocellulosic material saccharification for bioethanol production.

  5. Preparation and characterizations of naproxen-loaded magnetic nanoparticles coated with PLA- g-chitosan copolymer

    Science.gov (United States)

    Thammawong, C.; Sreearunothai, P.; Petchsuk, A.; Tangboriboonrat, P.; Pimpha, N.; Opaprakasit, P.

    2012-08-01

    Naproxen (NPX) drug-loaded magnetic nanoparticles (MNPs) have been prepared in a one-step process utilizing a biocompatible polylactide-grafted-chitosan copolymer. The copolymer serves both as a NPX drug carrier as well as a polymeric surfactant for the synthesis of MNPs without the use of any additional surfactant. Highly stable MNPs with high magnetization in the form of maghemite (γ-Fe2O3) are prepared in aqueous media. Effects of preparation conditions on structures and properties of the copolymer-coated and drug-loaded MNPs are investigated by employing particle size and zeta potential measurements, transmission electron microscopy, vibrating sample magnetometer, X-ray diffraction, Fourier-transform infrared, nuclear magnetic resonance, and confocal Raman spectroscopy. The results show that average particle size (150-300 nm), coating efficiency, and coating structures of the resulting MNPs materials are strongly dependent on MNP/copolymer and MNP/NPX ratios in feed. It is also observed that NPX acts as co-surfactant in the drug-loading process, resulting in different encapsulating structures with the variation in the MNP/copolymer and MNP/NPX ratios. Properties of the MNPs materials can be further optimized for use in specific biomedical applications.

  6. Preparation and characterizations of naproxen-loaded magnetic nanoparticles coated with PLA-g-chitosan copolymer

    Energy Technology Data Exchange (ETDEWEB)

    Thammawong, C.; Sreearunothai, P. [Thammasat University, School of Bio-Chemical Engineering and Technology, Sirindhorn International Institute of Technology (SIIT) (Thailand); Petchsuk, A. [National Metal and Materials Technology Center (MTEC) (Thailand); Tangboriboonrat, P. [Mahidol University, Department of Chemistry, Faculty of Science (Thailand); Pimpha, N. [National Nanotechnology Center (NANOTEC) (Thailand); Opaprakasit, P., E-mail: pakorn@siit.tu.ac.th [Thammasat University, School of Bio-Chemical Engineering and Technology, Sirindhorn International Institute of Technology (SIIT) (Thailand)

    2012-08-15

    Naproxen (NPX) drug-loaded magnetic nanoparticles (MNPs) have been prepared in a one-step process utilizing a biocompatible polylactide-grafted-chitosan copolymer. The copolymer serves both as a NPX drug carrier as well as a polymeric surfactant for the synthesis of MNPs without the use of any additional surfactant. Highly stable MNPs with high magnetization in the form of maghemite ({gamma}-Fe{sub 2}O{sub 3}) are prepared in aqueous media. Effects of preparation conditions on structures and properties of the copolymer-coated and drug-loaded MNPs are investigated by employing particle size and zeta potential measurements, transmission electron microscopy, vibrating sample magnetometer, X-ray diffraction, Fourier-transform infrared, nuclear magnetic resonance, and confocal Raman spectroscopy. The results show that average particle size (150-300 nm), coating efficiency, and coating structures of the resulting MNPs materials are strongly dependent on MNP/copolymer and MNP/NPX ratios in feed. It is also observed that NPX acts as co-surfactant in the drug-loading process, resulting in different encapsulating structures with the variation in the MNP/copolymer and MNP/NPX ratios. Properties of the MNPs materials can be further optimized for use in specific biomedical applications.

  7. Fabrication of mucoadhesive chitosan coated polyvinylpyrrolidone/cyclodextrin/clotrimazole sandwich patches for oral candidiasis.

    Science.gov (United States)

    Tonglairoum, Prasopchai; Ngawhirunpat, Tanasait; Rojanarata, Theerasak; Panomsuk, Suwanee; Kaomongkolgit, Ruchadaporn; Opanasopit, Praneet

    2015-11-05

    This study aims to fabricate clotrimazole (CZ)-composite sandwich nanofibers using electrospinning. The CZ-loaded polyvinylpyrrolidone (PVP)/hydroxypropyl-β-cyclodextrin (HPβCD) fiber was coated with chitosan-cysteine (CS-SH)/polyvinyl alcohol (PVA) to increase the mucoadhesive properties and to achieve a sustained release of the drug from the nanofibers. The nanofibers were characterized using scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy and X-ray diffractometry (XRD). The nanofibers mechanical and mucoadhesive properties, drug release, antifungal activity and cytotoxicity were also assessed. The fibers were in the nanoscale with good mucoadhesive properties. The XRPD revealed a molecular dispersion of amorphous CZ in the nanofibers. The initial fast release of CZ from the nanofibers was achieved. Moreover, the sandwich nanofibers coated for longer times resulted in slower release rates compared with the shorter coating times. The CZ-loaded nanofibers killed the Candida significantly faster than the commercial CZ lozenges at 5, 15 and 30 min and were safe for a 2-h incubation. Therefore, these nanofibers may be promising candidates for the treatment of oral candidiasis.

  8. Preparation of Chitosan Coated Magnetic Hydroxyapatite Nanoparticles and Application for Adsorption of Reactive Blue 19 and Ni2+ Ions

    Directory of Open Access Journals (Sweden)

    Van Cuong Nguyen

    2014-01-01

    Full Text Available An adsorbent called chitosan coated magnetic hydroxyapatite nanoparticles (CS-MHAP was prepared with the purpose of improvement for the removal of Ni2+ ions and textile dye by coprecipitation. Structure and properties of CS-MHAP were characterized by scanning electron microscopy (SEM, X-ray diffraction (XRD, Fourier transform infrared spectroscopy (FTIR, and vibrating sample magnetometer (VSM. Weight percent of chitosan was investigated by thermal gravimetric analysis (TGA. The prepared CS-MHAP presents a significant improvement on the removal efficiency of Ni2+ ions and reactive blue 19 dye (RB19 in comparison with chitosan and magnetic hydroxyapatite nanoparticles. Moreover, the adsorption capacities were affected by several parameters such as contact time, initial concentration, adsorbent dosage, and initial pH. Interestingly, the prepared adsorbent could be easily recycled from an aqueous solution by an external magnet and reused for adsorption with high removal efficiency.

  9. Efficacy of the combined application of chitosan and Locust Bean Gum with different citrus essential oils to control postharvest spoilage caused by Aspergillus flavus in dates.

    Science.gov (United States)

    Aloui, Hajer; Khwaldia, Khaoula; Licciardello, Fabio; Mazzaglia, Agata; Muratore, Giuseppe; Hamdi, Moktar; Restuccia, Cristina

    2014-01-17

    This study reports the efficacy of the combined application of chitosan (CH) and Locust Bean Gum (LBG) in combination with different citrus essential oils (EOs) to inhibit Aspergillus flavus in vitro and on artificially infected dates for a storage period of 12 days. The effect of these treatments on the fruits' sensory characteristics was evaluated to verify the complete absence of off-odours and off-flavours. Bergamot EO was the most effective in reducing mycelial growth, followed by bitter orange EO. Both bergamot and bitter orange oils significantly reduced conidial germination and a complete inhibition was obtained at concentrations higher than 2%. The mixtures based on CH-2% (v/v) bergamot EO or CH-2% (v/v) bitter orange EO proved to be the most effective coatings to reduce conidial germination resulting in an 87-90% inhibition compared with the control. In fruit decay assays coatings based on CH incorporating citrus oils were able to reduce fungal decay in the range of 52-62% at day 12. The study results and the complete absence of off-flavours and off-odours demonstrate the potential of CH coatings carrying citrus EOs at sub-inhibitory concentrations to control postharvest growth of A. flavus in dates.

  10. Vancomycin–chitosan composite deposited on post porous hydroxyapatite coated Ti6Al4V implant for drug controlled release

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Chi-Chuan [Department of Materials Science and Engineering, National Chung Hsing, University 250, Kuo-Kuang Road, Taichung 40227, Taiwan (China); Lin, Chien-Chung [Department of Materials Science and Engineering, National Chung Hsing, University 250, Kuo-Kuang Road, Taichung 40227, Taiwan (China); Department of Orthopaedic Surgery, Taichung Armed Force General Hospital, 348, Sec. 2, Jhongshan Road, Taiping City, Taichung 411, Taiwan (China); Liao, Jiunn-Wang [Graduate Institute of Veterinary Pathobiology, National Chung Hsing, University 250, Kuo-Kuang Road, Taichung 40227, Taiwan (China); Yen, Shiow-Kang, E-mail: skyen@dragon.nchu.edu.tw [Department of Materials Science and Engineering, National Chung Hsing, University 250, Kuo-Kuang Road, Taichung 40227, Taiwan (China)

    2013-05-01

    Through the hydrogen bonds and the deprotonation, the vancomycin–chitosan composite has been originally deposited on Ti4Al4V by electrochemical technology. However, the rapid destruction of the hydrogen bonding between them by polar water molecules during immersion tests revealed 80% drug burst in a few hours. In this study, the post porous hydroxyapatite (HA) coated Ti4Al4V is prepared for the subsequent electrolytic deposition of vancomycin–chitosan composite to control the drug release. As expected, the initial burst is reduced to 55%, followed by a steady release about 20% from day 1 to day 5 and a slower release of the retained 25% after day 6, resulting in bacterial inhibition zone diameter of 30 mm which can last for more than a month in antibacterial tests, compared with the coated specimen without HA gradually loosing inhibition zone after 21 days. Besides, the cell culture indicates that the vancomycin–chitosan/HA composite coated has enhanced the proliferation, the differentiation and the mineralization of the osteoblast-like cell. In general, it is helpful for the osteointegration on permanent implants. Consistently, it effectively provides the prophylaxis and therapy of osteomyelitis according to the results of the rabbit infection animal model. - Highlights: ► The releasing curve of the vancomycin–chitosan/HA composite revealed three periods. ► The drug release sustained one month due to the effect of post porous HA coating. ► The composite coating could treat the osteomyelitis in the rabbit infection model.

  11. Alginate coated chitosan core shell nanoparticles for oral delivery of enoxaparin: in vitro and in vivo assessment.

    Science.gov (United States)

    Bagre, Archana Pataskar; Jain, Keerti; Jain, Narendra K

    2013-11-01

    The objective of present research work was to develop alginate coated chitosan core shell nanoparticles (Alg-CS-NPs) for oral delivery of low molecular weight heparin, enoxaparin. Chitosan nanoparticles (CS-NPs) were synthesized by ionic gelation of chitosan using sodium tripolyphosphate. Core shell nanoparticles were prepared by coating CS-NPs with alginate solution under mild agitation. The Alg-CS-NPs were characterized for surface morphology, surface coating, particle size, polydispersity index, zeta potential, drug loading and entrapment efficiency using SEM, Zeta-sizer, FTIR and DSC techniques. Alginate coating increased the size of optimized chitosan nanoparticles from around 213 nm to about 335 nm as measured by dynamic light scattering in zeta sizer and further confirmed by SEM analysis. The performance of optimized enoxaparin loaded Alg-CS-NPs was evaluated by in vitro drug release studies, in vitro permeation study across intestinal epithelium, in vivo venous thrombosis model, particulate uptake by intestinal epithelium using fluorescence microscopy and pharmacokinetic studies in rats. Coating of alginate over the CS-NPs improved the release profile of enoxaparin from the nanoparticles for successful oral delivery. In vitro permeation studies elucidated that more than 75% enoxaparin permeated across the intestinal epithelium with Alg-CS-NPs. The Alg-CS-NPs significantly increased (p<0.05) the oral bioavailability of enoxaparin in comparison to plain enoxaparin solution as revealed by threefold increase in AUC of plasma drug concentration time curve and around 60% reduction in thrombus formation in rat venous thrombosis model. The core shell Alg-CS-NPs showed promising potential for oral delivery and significantly enhanced the in vivo oral absorption of enoxaparin.

  12. Study on the bonding strength between calcium phosphate/chitosan composite coatings and a Mg alloy substrate

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Jie [School of Chemistry Engineering and Technology, Harbin Institute of Technology, Harbin 150001 (China); Pharmacy College, Jiamusi University, Jiamusi 154007 (China); Dai Changsong, E-mail: changsd@hit.edu.cn [School of Chemistry Engineering and Technology, Harbin Institute of Technology, Harbin 150001 (China); Wei Jie [School of Chemistry Engineering and Technology, Harbin Institute of Technology, Harbin 150001 (China); School of Chemistry and Bioengineering, Suzhou Science Technology University, Suzhou 215009 (China); Wen Zhaohui, E-mail: wenzhaohui1968@163.com [Department of Neuro intern, First Affiliated Hospital of Harbin Medical University, Harbin 150001 (China)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer Calcium phosphate/chitosan composite coatings on the MAO-AZ91D alloy were prepared. Black-Right-Pointing-Pointer The bonding force between the coating and the magnesium alloy was optimized. Black-Right-Pointing-Pointer The composite coating slowed down the corrosion rate of magnesium alloy in m-SBF. - Abstract: In order to improve the bonding strength between calcium phosphate/chitosan composite coatings and a micro-arc oxidized (MAO)-AZ91D Mg alloy, different influencing parameters were investigated in the process of electrophoretic deposition (EPD) followed by conversion in a phosphate buffer solution (PBS). Surface morphology and phase constituents of the as-prepared materials were investigated by using X-ray diffractometer (XRD), Fourier-transformed infrared spectrophotometer (FTIR), Raman spectrometer, scanning electron microscope (SEM) with an energy dispersive spectrometer (EDS), and a thermo gravimetric and differential thermal analyzer (TG-DTA). Scratch tests were carried out to study the bonding properties between the coatings and the substrates. In vitro immersion tests were conducted to determine the corrosion behaviors of samples with and without deposit layers through electrochemical experiments. In the EPD process, the acetic acid content in the electrophoresis suspension and the electrophoretic voltage played important roles in improving the bonding properties, while the contents of chitosan (CS) and nano-hydroxyapatite (nHA, Ca{sub 10}(PO{sub 4}){sub 6}(OH){sub 2}) in the suspension had less significant influences on the mechanical bonding strength. It was observed that the coatings showed the excellent bonding property when an electrophoretic voltage was in a range of 40-110 V with other reagent amounts as follows: acetic acid: 4.5 vol.%, CS {<=} 0.25 g, nHA {<=} 2.0 g in 200 ml of a CS-acetic acid aqueous solution and nHA {<=} 2.5 g in 300 ml of absolute ethanol. The morphology of the composite coating

  13. Chitosan-Based Aerogel Membrane for Robust Oil-in-Water Emulsion Separation.

    Science.gov (United States)

    Chaudhary, Jai Prakash; Vadodariya, Nilesh; Nataraj, Sanna Kotrappanavar; Meena, Ramavatar

    2015-11-11

    Here, we demonstrate direct recovery of water from stable emulsion waste using aerogel membrane. Chitosan-based gel was transformed into highly porous aerogel membrane using bio-origin genipin as cross-linking agent. Aerogel membranes were characterized for their morphology using SEM, chemical composition by FTIR and solid-UV. Further, aerogel was tested for recovery of high quality water from oil spill sample collected from ship breaking yard. High quality (with >99% purity) water was recovered with a flux rate of >600 L·m(-2)·h(-1)·bar(-1). After repeated use, aerogel membranes were tested for greener disposal possibilities by biodegrading membrane in soil.

  14. Mg-Doped Hydroxyapatite/Chitosan Composite Coated 316L Stainless Steel Implants for Biomedical Applications.

    Science.gov (United States)

    Sutha, S; Dhineshbabu, N R; Prabhu, M; Rajendran, V

    2015-06-01

    In this investigation, ultrasonication process was used for the synthesis of magnesium doped nano-hydroxyapatite (MH) (0, 1, 2, and 3 mol% of Mg concentration) particles with controlled size and surface morphology. The size of the prepared MH particles was in the range of 20-100 nm with narrow distribution. Increase in the concentration of Mg reduced the particle size distribution from 60 to 40 nm. On incorporation of Mg in HAp lattice, an increase of 20-66 nm in specific surface area was observed in microporous HAp particles. XRF and XRD patterns reveal that the particles possess stoichiometric composition with reduced crystallinity with respect to the Mg concentration. Surface morphology of MH/chitosan (CTS) coated implant was found to be uniform without any defects. The corrosion rate of the implant decreased with increase in Mg concentration. The in vitro formation of bonelike apatite layer on the surface of the MH/CTS coated implant was observed from simulated body fluid studies. The antimicrobial activity of the MH/CTS composites against gram-positive and gram-negative bacterial strains indicated that increasing Mg concentration enhanced antimicrobial properties. Nanoindentation analysis of apatite coated implant surface reveals that the mechanical property depends on the concentration of magnesium in HAp. From the cytotoxicity analysis against NIH 3T3 fibroblast, it was observed that the Mg incorporated HAp/CTS composite was less toxic than the MHO/CTS composite. From this result, it was concluded that the MH/CTS nanocomposites coated implant is the excellent material for implants.

  15. Role of Counterions in Controlling the Properties of Ultrasonically Generated Chitosan-Stabilized Oil-in-Water Emulsions.

    Science.gov (United States)

    Colombo, Enrico; Cavalieri, Francesca; Ashokkumar, Muthupandian

    2015-06-17

    An oil-in-water emulsion was ultrasonically prepared in aqueous chitosan solutions containing different counterions. Tetradecane was used as the oil phase in order to mimic nonpolar substances used in food processes. Various acids were used to dissolve chitosan, and we found that conjugate bases of the acids used, which act as counterions to neutralize the positive charges of ammonium ions present in the chitosan backbone, played a significant role in controlling the size, size distribution, and stability of chitosan-encapsulated tedradecane emulsion droplets (microspheres). The counterion effect is also found to be strongly dependent upon tetradecane (TD)/chitosan (CS) ratio and ultrasonic power. Key observations are: (i) for a given TD/CS ratio, the size and size distribution decrease when the acid is varied from nitric acid to benzenesulfonic acid at high TD/CS ratio, and the effect becomes less significant at low TD/CS ratio; (ii) for a given acid, the size and size distribution increase with an increase in TD/CS ratio; and (iii) at low TD/CS ratio the size and size distribution are significantly influenced by the viscosity of the system. A possible mechanism for the observed counterion effect is proposed. The role of counterions, solution viscosity, and ultrasonic power in controlling the physical and functional properties of ultrasonically generated chitosan-stabilized tetradecane microspheres is discussed in detail. The key new finding of this study is that it is possible to form stable emulsions without the addition of external emulsifiers and stabilizers, but only using chitosan with different acids to dissolve chitosan. This strategy could be used in the generation of stable food emulsions.

  16. ANTIMICROBIAL PROPERTIES OF HYDROXYAPATITE COATINGS CONTAINING OF CHITOSAN AND SILVER ON TITANIUM SUBSTRATES IN RELATION TO MICROORGANISMS E.COLI ATCC 25922

    Directory of Open Access Journals (Sweden)

    Sukhodub LB

    2013-03-01

    Full Text Available In this work it was studied the antibacterial properties of coatings based on HA, with Chitosan and silver ions additions, produced by substrates termodeposition method from aqueous solutions with varying concentrations of Chitosan (0.025 and 0.1 g/l and silver (1 mg/l as the antimicrobial components as well as three-part cover, consisting of a film of Chitosan, HA and silver. Study on antibacterial properties of composite coatings on the pathogen E.coli ATCC 25922 was held by Spectrophotometric measurement and analysis of optical density of suspensions, containing samples. 3 series of measurements data were averaged. The results showed that the concentration of antimicrobial components have indicated a bacteriostatic effect of coatings on the culture of E. coli AS ATCC 25922 in physiological solution at a temperature of 37 °C. The most effective was the three-part cover consisting of a film of chitosan, HA and silver.

  17. Bovine Serum Albumin and Chitosan Coated Silver Nanoparticles and Its Antimicrobial Activity against Oral and Nonoral Bacteria

    Directory of Open Access Journals (Sweden)

    León Francisco Espinosa-Cristóbal

    2015-01-01

    Full Text Available Antimicrobial agents have been developed for drug-resistance infections, which have been rapidly increasing; however, the control of involved microorganisms is still a challenge. In this work, SNP with bovine serum albumin (BSA and chitosan (CS coatings were prepared with an aqueous reduction method, characterized using dispersion light scattering, transmission electron microscopy, and thermal analysis. Antibacterial activity was tested on seven oral and nonoral bacteria by microdilution test and scanning electron microscopy. Six different sizes and shapes of coated SNP were prepared and used. Characterization revealed narrow size and good distribution of particles, spherical and pseudospherical shapes, and the presence of coatings on the SNP surfaces. All samples showed antimicrobial activity, although smaller sizes and CS samples had the best inhibition effects. The highest microbial resistance was shown by Gram-positive bacteria. Although coated SNP action depends on particular bacterium, BSA and CS coated SNP could be used for drug-resistance infections.

  18. Haemostatic chitosan coated gauze: in vitro interaction with human blood and in-vivo effectiveness

    OpenAIRE

    Pogorielov, M.; Kalinkevich, O.; Deineka, V.; Garbuzova, V.; Solodovnik, A.; Kalinkevich, A.; Kalinichenko, T.; Gapchenko, A.; Sklyar, A.; Danilchenko, S.

    2015-01-01

    Background Chitosan and its derivates are widely used for biomedical application due to antioxidative, anti-inflammatory, antimicrobial and tissue repair induced properties. Chitosan-based materials also used as a haemostatic agent but influence of different molecular weight and concentration of chitosan on biological response of blood cells is still not clear. The aim of this research was to evaluate interaction between human blood cells and various forms of chitosan-based materials with dif...

  19. Vancomycin-chitosan composite deposited on post porous hydroxyapatite coated Ti6Al4V implant for drug controlled release.

    Science.gov (United States)

    Yang, Chi-Chuan; Lin, Chien-Chung; Liao, Jiunn-Wang; Yen, Shiow-Kang

    2013-05-01

    Through the hydrogen bonds and the deprotonation, the vancomycin-chitosan composite has been originally deposited on Ti4Al4V by electrochemical technology. However, the rapid destruction of the hydrogen bonding between them by polar water molecules during immersion tests revealed 80% drug burst in a few hours. In this study, the post porous hydroxyapatite (HA) coated Ti4Al4V is prepared for the subsequent electrolytic deposition of vancomycin-chitosan composite to control the drug release. As expected, the initial burst is reduced to 55%, followed by a steady release about 20% from day 1 to day 5 and a slower release of the retained 25% after day 6, resulting in bacterial inhibition zone diameter of 30 mm which can last for more than a month in antibacterial tests, compared with the coated specimen without HA gradually loosing inhibition zone after 21 days. Besides, the cell culture indicates that the vancomycin-chitosan/HA composite coated has enhanced the proliferation, the differentiation and the mineralization of the osteoblast-like cell. In general, it is helpful for the osteointegration on permanent implants. Consistently, it effectively provides the prophylaxis and therapy of osteomyelitis according to the results of the rabbit infection animal model.

  20. Synthesis and characterization of zinc oxide-neem oil-chitosan bionanocomposite for food packaging application.

    Science.gov (United States)

    Sanuja, S; Agalya, A; Umapathy, M J

    2015-03-01

    Nano zinc oxide at different concentrations (0.1, 0.3 and 0.5%) and neem essential oil were incorporated into the chitosan polymer by solution cast method to enhance the properties of the bionanocomposite film. The functional groups, crystalline particle size, thermal stability and morphology were determined using FTIR, XRD, TGA and SEM, respectively. The results showed that 0.5% nano zinc oxide incorporated composite film have improved tensile strength, elongation, film thickness, film transparency and decreased water solubility, swelling and barrier properties due to the presence of neem oil and nano zinc oxide in the polymer matrix. Further antibacterial activity by well diffusion assay method was followed against Escherichia coli which were found to have good inhibition effect. In addition to this food quality application were carried against carrot and compared with the commercial film.

  1. Quaternized chitosan/κ-carrageenan/caffeic acid-coated poly(3-hydroxybutyrate) fibrous materials: Preparation, antibacterial and antioxidant activity.

    Science.gov (United States)

    Ignatova, Milena; Manolova, Nevena; Rashkov, Iliya; Markova, Nadya

    2016-11-20

    Novel fibrous materials with antioxidant and antibacterial properties from poly(3-hydroxybutyrate) (PHB), quaternized chitosan (QCh), κ-carrageenan (Car) and caffeic acid (CA) were obtained. These materials were prepared by applying electrospinning or electrospinning in conjunction with dip-coating and polyelectrolyte complex (PEC) formation. It was found that the CA release depended on the fiber composition. X-ray diffraction analysis (XRD) and differential scanning calorimetry (DSC) revealed that CA incorporated in the fibers was in the amorphous state, whereas CA included in the coating was in the crystalline state. In contrast to the neat PHB mats, the CA-containing mats and the PEC QCh/Car-coated mats were found to kill the Gram-positive bacteria S. aureus and the Gram-negative bacteria E. coli and were effective in suppressing the adhesion of pathogenic bacteria S. aureus. Enhancement of the antioxidant activity of the fibrous materials containing both CA and QCh/Car coating was observed.

  2. Synthesis and characterization of chitosan/Mg-Al layered double hydroxide composite for the removal of oil particles from oil-in-water emulsion.

    Science.gov (United States)

    Elanchezhiyan, S Sd; Meenakshi, Sankaran

    2017-01-23

    The recovery of oil from oil-in-water emulsion has been investigated using chitosan/magnesium-aluminium layered double hydroxide hybrid composite (CS-LDHCs) by a single co-precipitation method. Resulting better adsorption efficiency of CS-LDHCs could be observed, indicating the synthesized material was effective to adsorb oil particles from oil-in-water emulsion at acidic pH (pH 3.0) than as-prepared LDH and raw chitosan. The enhancement of adsorption properties by CS-LDHCs material were attributed to the high content of LDH in chitosan, which makes the material more effective towards immobilization of oily particles. Batch experiment study has been elucidated by varying different physicochemical parameters such as time, pH, dose, initial oil concentration and temperature. The as-synthesized CS-LDHCs was characterized by various spectro analytical techniques viz., FTIR, SEM with EDAX, XRD, TGA and DSC analysis. To find out the best fit for the sorption process, the obtained adsorption equilibrium data was explained with Freundlich, Langmuir, Dubinin-Radushkevich and Tempkin isotherm models. The mechanism of adsorption process was demonstrated by calculating ΔG°, ΔH° and ΔS° values from thermodynamic parameters in order to understand the nature of sorption process. The schematic representation of oil removal using CS-LDHCs was explored in detail. This work provides an apparent proposal for the growth of oil removal technology.

  3. Synthesis, characterization, and nuclear magnetic resonance study of chitosan-coated Mn(₁-x)Zn(x)Fe₂O₄ nanocrystals.

    Science.gov (United States)

    Hoque, S Manjura; Srivastava, C; Venkatesha, N; Chattopadhyay, K

    2013-12-01

    Ultra-fine crystallites of Mn(₁-x)Zn(x)Fe₂O₄ series (0 ≤ x ≤ 1) were synthesized through wet chemical co-precipitation method followed by calcination at 200 °C for 4 hours. Formation of ferrites was confirmed by X-ray diffraction, TEM selected area diffraction (SAD) and Fourier Transform Infra-red Spectroscopy (FTIR). Nanocrystallites of different compositions in the series were coated with biocompatible chitosan in order to investigate their possible application as contrast agent for magnetic resonance imaging (MRI). Chitosan coating examined by FTIR, revealed a strong bonding of chitosan molecules to the surface of the ferrite nanocrystallites. Spin-spin, τ₂ relaxivities of nuclear spins of hydrogen protons of the solutions for different ferrites were measured from concentration dependence of relaxation time by nuclear magnetic resonance (NMR). All the compositions Mn(₁-x)Zn(x)Fe₂O₄ of series possess higher values of τ₂ relaxivity thus making them suitable as contrast agents for τ₂ weighted imaging by MRI.

  4. Eucalyptus oil nanoemulsion-impregnated chitosan film: antibacterial effects against a clinical pathogen, Staphylococcus aureus, in vitro

    Directory of Open Access Journals (Sweden)

    Sugumar S

    2015-10-01

    Full Text Available Saranya Sugumar, Amitava Mukherjee, Natarajan Chandrasekaran Centre for Nanobiotechnology, VIT University, Vellore, India Abstract: Eucalyptus oil (Eucalyptus globulus nanoemulsion was formulated using low- and high-energy emulsification methods. Development of nanoemulsion was optimized for system parameters such as emulsifier type, emulsifier concentration, and emulsification methods to obtain a lower droplet size with greater stability. The minimized droplet diameter was achieved using the high-energy method of ultrasonication. Tween 80 was more effective in reducing droplet size and emulsion appearance when compared to Tween 20. Stable nanoemulsion was formulated with Tween 80 as a surfactant, and the particle size was found to be 9.4 nm (1:2 v/v. The eucalyptus oil nanoemulsion was impregnated into chitosan (1% as a biopolymer in varying concentrations. Further, the film was characterized by moisture content, microscopic study, X-ray diffraction, and Fourier transform infrared spectroscopy. Also, the film with and without nanoemulsion was evaluated against Staphylococcus aureus. The nanoemulsion-impregnated chitosan film showed higher antibacterial activity than chitosan film. These results support the inclusion of nanoemulsion-impregnated chitosan film in wound management studies. Keywords: essential oil, emulsion, biopolymer, impregnation, thin film, wound isolate

  5. Biodegradable Chitosan Nanoparticle Coatings on Titanium for the Delivery of BMP-2

    OpenAIRE

    Nils Poth; Virginia Seiffart; Gerhard Gross; Henning Menzel; Wibke Dempwolf

    2015-01-01

    A simple method for the functionalization of a common implant material (Ti6Al4V) with biodegradable, drug loaded chitosan-tripolyphosphate (CS-TPP) nanoparticles is developed in order to enhance the osseointegration of endoprostheses after revision operations. The chitosan used has a tailored degree of acetylation which allows for a fast biodegradation by lysozyme. The degradability of chitosan is proven via viscometry. Characteristics and degradation of nanoparticles formed with TPP are anal...

  6. Influence of Chitosan Coating on Mechanical Stability of Biopolymer Carriers with Probiotic Starter Culture in Fermented Whey Beverages

    Directory of Open Access Journals (Sweden)

    Nataša S. Obradović

    2015-01-01

    Full Text Available The aim of this study was to improve the mechanical stability of biopolymer carriers and cell viability with addition of chitosan coating during fermentation process and product storage. Dairy starter culture (1% (w/v was diluted in whey and mixed with sodium alginate solution and the beads were made using extrusion technique. The mechanical stability of coated and uncoated beads, the release behavior, and the viability of encapsulated probiotic dairy starter culture in fermented whey beverages were analyzed. The mechanical properties of the beads were determined according to force-displacement and engineering stress-strain curves obtained after compression testing. It was observed that addition of chitosan as a coating on the beads as well as the fermentation process increased the elastic modulus of the calcium alginate-whey beads and cell survival. The current study revealed that the coating did not significantly improve the viability of probiotics during the fermentation but had an important influence on preservation of the strength of the carrier during storage. Our results indicate that whey-based substrate has positive effect on the mechanical stability of biopolymer beads with encapsulated probiotics.

  7. Tight attachment of chitin-binding-domain-tagged proteins to surfaces coated with acetylated chitosan.

    Science.gov (United States)

    Bernard, Michael P; Cao, Donghui; Myers, Rebecca V; Moyle, William R

    2004-04-15

    Several excellent procedures for trapping tagged proteins have been devised, but many of these are expensive, cannot be used outside a limited pH range, fail to work in the presence of chaotropic agents, or are difficult to use. The chitin binding domain (CBD) of Bacillus circulans chitinase, which binds to chitin matrices prepared from inexpensive reagents isolated from crab shells, is an alternative tag that can be used under a variety of pH and denaturing conditions. Kits based on the interaction between the CBD and the chitin beads are available commercially. Here, we show that simultaneous treatment of microtiter plates with chitosan, a deacetylated form of chitin, and acetic anhydride produces a surface-bound film of chitin that also interacts tightly with the CBD. Chitin-coated microtiter well plates captured a CBD-tagged heterodimeric human glycoprotein hormone analog directly from mammalian cell culture media, even when present in trace amounts. Binding to the surface was stable in sodium dodecylsulfate and reversed only partially at low pH or in 8M urea at 37 degrees C. This technique appears well suited to surface attachment and permits biochemical or other analyses of molecules that can be tagged with a CBD.

  8. Removal and recovery of Hg(II) from aqueous solution using chitosan-coated cotton fibers.

    Science.gov (United States)

    Qu, Rongjun; Sun, Changmei; Ma, Fang; Zhang, Ying; Ji, Chunnuan; Xu, Qiang; Wang, Chunhua; Chen, Hou

    2009-08-15

    Two types of chitosan-coated cotton fibers (SCCH and RCCH) were applied to remove and recover Hg(II) ions in aqueous solution. The adsorption kinetics and isotherms of the two fibers for Hg(II) were investigated at different temperatures. The results revealed that the adsorption kinetic processes of SCCH and RCCH fibers for Hg(II) followed the pseudo second-order model at lower temperatures and the pseudo first-order model at higher temperatures. Both the Langmuir and Freundlich models well described the adsorption isotherms of SCCH and RCCH fibers for Hg(II) in the temperature range studied. SCCH and RCCH fibers selectively adsorbed Hg(II) from binary ion systems in the presence of Pb(II), Cu(II), Ni(II), Cd(II), Zn(II), Co(II), Mn(II) and Ag(I). Increased temperature was beneficial to adsorption. The recovery of Hg(II) from aqueous solutions was also studied as a function of sample flow rate and volume, concentration and volume of eluent, elution rate, quantity of adsorbents added and concomitant ions. The results showed that the two fibers efficiently enriched and recovered Hg(II) in the presence of alkali and alkaline earth metals and some heavy metals under optimum conditions. The RCCH fiber exhibited better stability than the SCCH fiber following repeated use.

  9. Combinatorial photothermal and immuno cancer therapy using chitosan-coated hollow copper sulfide nanoparticles.

    Science.gov (United States)

    Guo, Liangran; Yan, Daisy D; Yang, Dongfang; Li, Yajuan; Wang, Xiaodong; Zalewski, Olivia; Yan, Bingfang; Lu, Wei

    2014-06-24

    Near-infrared light-responsive inorganic nanoparticles have been shown to enhance the efficacy of cancer photothermal ablation therapy. However, current nanoparticle-mediated photothermal ablation is more effective in treating local cancer at the primary site than metastatic cancer. Here, we report the design of a near-infrared light-induced transformative nanoparticle platform that combines photothermal ablation with immunotherapy. The design is based on chitosan-coated hollow CuS nanoparticles that assemble the immunoadjuvants oligodeoxynucleotides containing the cytosine-guanine (CpG) motifs. Interestingly, these structures break down after laser excitation, reassemble, and transform into polymer complexes that improve tumor retention of the immunotherapy. In this "photothermal immunotherapy" approach, photothermal ablation-induced tumor cell death reduces tumor growth and releases tumor antigens into the surrounding milieu, while the immunoadjuvants potentiate host antitumor immunity. Our results indicated that combined photothermal immunotherapy is more effective than either immunotherapy or photothermal therapy alone against primary treated and distant untreated tumors in a mouse breast cancer model. These hollow CuS nanoparticles are biodegradable and can be eliminated from the body after laser excitation.

  10. Adsorption of indium(III) ions from aqueous solution using chitosan-coated bentonite beads

    Energy Technology Data Exchange (ETDEWEB)

    Calagui, Mary Jane C. [College of Engineering, Cagayan State University, Cagayan Valley 3500 (Philippines); School of Graduate Studies, Mapua Institute of Technology, Manila 1800 (Philippines); Senoro, Delia B. [School of Graduate Studies, Mapua Institute of Technology, Manila 1800 (Philippines); Kan, Chi-Chuan [Institute of Hot Spring Industrial, Chia Nan University of Pharmacy and Science, Tainan 71710, Taiwan (China); Salvacion, Jonathan W.L. [School of Graduate Studies, Mapua Institute of Technology, Manila 1800 (Philippines); Futalan, Cybelle Morales [Operations Department, Frontier Oil Corporation, Makati City 1229 (Philippines); Wan, Meng-Wei, E-mail: peterwan@mail.chna.edu.tw [Department of Environmental Engineering and Science, Chia Nan University of Pharmacy and Science, Tainan 71710, Taiwan (China)

    2014-07-30

    Highlights: • A more acidic pH causes a decrease in adsorption capacity. • The kinetic data follow the pseudo-second order equation. • Equilibrium data correlated well with Langmuir isotherm. • Removal of indium is a spontaneous and endothermic process. - Abstract: Batch adsorption study was utilized in evaluating the potential suitability of chitosan-coated bentonite (CCB) as an adsorbent in the removal of indium ions from aqueous solution. The percentage (%) removal and adsorption capacity of indium(III) were examined as a function of solution pH, initial concentration, adsorbent dosage and temperature. The experimental data were fitted with several isotherm models, where the equilibrium data was best described by Langmuir isotherm. The mean energy (E) value was found in the range of 1–8 kJ/mol, indicating that the governing type of adsorption of indium(III) onto CCB is essentially physical. Thermodynamic parameters, including Gibbs free energy, enthalpy, and entropy indicated that the indium(III) ions adsorption onto CCB was feasible, spontaneous and endothermic in the temperature range of 278–318 K. The kinetics was evaluated utilizing the pseudo-first order and pseudo-second order model. The adsorption kinetics of indium(III) best fits the pseudo-second order (R{sup 2} > 0.99), which implies that chemical sorption as the rate-limiting step.

  11. Nanostructured polymeric coatings based on chitosan and dopamine-modified hyaluronic acid for biomedical applications.

    Science.gov (United States)

    Neto, Ana I; Cibrão, Ana C; Correia, Clara R; Carvalho, Rita R; Luz, Gisela M; Ferrer, Gloria G; Botelho, Gabriela; Picart, Catherine; Alves, Natália M; Mano, João F

    2014-06-25

    In a marine environment, specific proteins are secreted by mussels and used as a bioglue to stick to a surface. These mussel proteins present an unusual amino acid 3,4-dihydroxyphenylalanine (known as DOPA). The outstanding adhesive properties of these materials in the sea harsh conditions have been attributed to the presence of the catechol groups present in DOPA. Inspired by the structure and composition of these adhesive proteins, dopamine-modified hyaluronic acid (HA-DN) prepared by carbodiimide chemistry is used to form thin and surface-adherent dopamine films. This conjugate was characterized by distinct techniques, such as nuclear magnetic resonance and ultraviolet spectrophotometry. Multilayer films are developed based on chitosan and HA-DN to form polymeric coatings using the layer-by-layer methodology. The nanostructured films formation is monitored by quartz crystal microbalance. The film surface is characterized by atomic force microscopy and scanning electron microscopy. Water contact angle measurements are also conducted. The adhesion properties are analyzed showing that the nanostructured films with dopamine promote an improved adhesion. In vitro tests show an enhanced cell adhesion, proliferation and viability for the biomimetic films with catechol groups, demonstrating their potential to be used in distinct biomedical applications.

  12. Encapsulation of Mentha Oil in Chitosan Polymer Matrix Alleviates Skin Irritation.

    Science.gov (United States)

    Mishra, Nidhi; Rai, Vineet Kumar; Yadav, Kuldeep Singh; Sinha, Priyam; Kanaujia, Archana; Chanda, Debabrata; Jakhmola, Apurva; Saikia, Dharmendra; Yadav, Narayan Prasad

    2016-04-01

    Mentha spicata L. var. viridis oil (MVO) is a potent antifungal agent, but its application in the topical treatment is limited due to its irritancy and volatility. It was aimed to develop more efficient, chitosan-incrusted MVO microspheres with reduced volatility and lesser irritancy and to dispense it in the form of ointment. Simple coacervation technique was employed to microencapsulate MVO in chitosan matrix. Morphological properties and polymer cross-linking were characterized by scanning electron microscopy and differential scanning calorimetry, respectively. Optimization was carried out on the basis of entrapment efficiency (EE) using response surface methodology. Well-designed microspheres having smooth surface and spherical shape were observed. EE (81.20%) of optimum batch (R21) was found at 1.62% w/v of cross-linker, 5.4:5 of MVO to chitosan ratio and at 1000 rpm. R21 showed 69.38 ± 1.29% in vitro MVO release in 12 h and 96.92% retention of MVO in microspheres even after 8 week. Ointments of PEG 4000 and PEG 400 comprising MVO (F1) and R21 (F2) were developed separately. F2 showed comparatively broader zone of growth inhibition (13.33 ± 1.76-18.67 ± 0.88 mm) and less irritancy (PII 0.5833, irritation barely perceptible) than that of F1. F2 was able to avoid the direct contact of mild irritant MVO with the skin and to reduce its rapid volatility. Controlled release of MVO helped in lengthening the duration of availability of MVO in agar media and hence improved its therapeutic efficacy. In conclusion, a stable and non-irritant formulation with improved therapeutic potential was developed.

  13. Carbon coatings with olive oil, soybean oil and butter on nano-LiFePO 4

    Science.gov (United States)

    Kim, Ketack; Jeong, Ji Hwa; Kim, Ick-Jun; Kim, Hyun-Soo

    Kitchen oils (olive, soybean and butter) are selected for carbon coatings on LiFePO 4. The surface properties of LiFePO 4 are unknown or vary depending on synthetic methods. The multi-functional groups of fatty acids in the oils can orient properly to cope with the variable surface properties of LiFePO 4, which can lead to dense carbon coatings. The low price and low toxicity of kitchen oils are other advantages of the coating process. LiFePO 4 (D 50 = 121 nm)combined with the carbon coating enhances the rate capability. Capacities at the 2 C rate reach 150 mAh g -1 or higher. The charge retention values of 2.0 C/0.2 C are between 94.4 and 98.9%.

  14. Preparation of chitosan nanofiber tube by electrospinning.

    Science.gov (United States)

    Matsuda, Atsushi; Kagata, Go; Kino, Rikako; Tanaka, Junzo

    2007-03-01

    Water-insoluble chitosan nanofiber sheets and tubes coated with chitosan-cast film were prepared by electrospinning. When as-spun chitosan nanofiber sheets and tubes were immersed in 28% ammonium aqueous solution, they became insoluble in water and showed nanofiber structures confirmed by SEM micrography. Mechanical properties of chitosan nanofiber sheets and tubes were improved by coating with chitosan-cast film, which gave them a compressive strength higher than that of crab-tendon chitosan, demonstrating that chitosan nanofiber tubes coated with chitosan-cast film are usable as nerve-regenerative guide tubes.

  15. Synthesis and characterization of chitosan-coated magnetite nanoparticles and their application in curcumin drug delivery

    Science.gov (United States)

    Nui Pham, Xuan; Phuoc Nguyen, Tan; Nhung Pham, Tuyet; Thuy Nga Tran, Thi; Van Thi Tran, Thi

    2016-12-01

    In this work anti-cancer drug curcumin-loaded superparamagnetic iron oxide (Fe3O4) nanoparticles was modified by chitosan (CS). The magnetic iron oxide nanoparticles were synthesized by using reverse micro-emulsion (water-in-oil) method. The magnetic nanoparticles without loaded drug and drug-loaded magnetic nanoparticles were characterized by XRD, FTIR, TG-DTA, SEM, TEM, and VSM techniques. These nanoparticles have almost spherical shape and their diameter varies from 8 nm to 17 nm. Measurement of VSM at room temperature showed that iron oxide nanoparticles have superparamagnetic properties. In vitro drug loading and release behavior of curcumin drug-loaded CS-Fe3O4 nanoparticles were studied by using UV-spectrophotometer. In addition, the cytotoxicity of the modified nanoparticles has shown anticancer activity against A549 cell with IC50 value of 73.03 μg/ml. Therefore, the modified magnetic nanoparticles can be used as drug delivery carriers on target in the treatment of cancer cells.

  16. Chitosan-coated boron nitride nanospheres enhance delivery of CpG oligodeoxynucleotides and induction of cytokines

    Directory of Open Access Journals (Sweden)

    Zhang H

    2013-05-01

    Full Text Available Huijie Zhang,1,2 Song Chen,3 Chunyi Zhi,4 Tomohiko Yamazaki,1,2 Nobutaka Hanagata1,2,5 1Graduate School of Life Science, Hokkaido University, Sapporo, Japan; 2Biomaterials Unit, International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Ibaraki, Japan; 3Japanese Society for the Promotion of Science, Tokyo, Japan; 4Department of Physics and Materials Science, City University of Hong Kong, Hong Kong, People’s Republic of China; 5Nanotechnology Innovation Station, Ibaraki, Japan Background: Cytosine-phosphate-guanine (CpG oligodeoxynucleotides activate Toll-like receptor 9, leading to induction of proinflammatory cytokines, which play an important role in induction and maintenance of innate and adaptive immune responses. Previously, we have used boron nitride nanospheres (BNNS as a carrier for delivery of unmodified CpG oligodeoxynucleotides to activate Toll-like receptor 9. However, because CpG oligodeoxynucleotides and BNNS are both negatively charged, electrostatic repulsion between them is likely to reduce the loading of CpG oligodeoxynucleotides onto BNNS. Therefore, the efficiency of uptake of CpG oligodeoxynucleotides is also limited and does not result in induction of a robust cytokine response. To ameliorate these problems, we developed a CpG oligodeoxynucleotide delivery system using chitosan-coated BNNS as a carrier. Methods: To facilitate attachment of CpG oligodeoxynucleotides onto the BNNS and improve their loading capacity, we prepared positively charged BNNS by coating them with chitosan preparations of three different molecular weights and used them as carriers for delivery of CpG oligodeoxynucleotides. Results: The zeta potentials of the BNNS-CS complexes were positive, and chitosan coating improved their dispersity and stability in aqueous solution compared with BNNS. The positive charge of the BNNS-CS complexes greatly improved the loading capacity and cellular uptake efficiency of Cp

  17. BMP2-encapsulated chitosan coatings on functionalized Ti surfaces and their performance in vitro and in vivo.

    Science.gov (United States)

    Han, Lu; Lin, Hong; Lu, Xiong; Zhi, Wei; Wang, Ke-Feng; Meng, Fan-Zhi; Jiang, Ou

    2014-07-01

    Bone morphogenic protein-2 (BMP2)-encapsulated chitosan (CS) coatings were prepared to immobilize BMP2 on titanium (Ti) surfaces. The Ti substrates were functionalized through a three-step process: alkali treatment, silanization with 3-aminopropyltriethoxysilane and aldehydation with glutaraldehyde (GA). BMP2-encapsulated CS coatings (BMP2-CS) were bonded to Ti surfaces through reactions between the aldehyde groups of GA and the amine groups of CS. Direct BMP2 immobilization on aldehyde-treated Ti (BMP2-Ti) and pure CS coatings (CS-Ti) were used as controls. The release rate of BMP2-CS-Ti was half of that of BMP2-Ti at initial stage, which indicates that the CS coatings are suitable carriers for sustained BMP2 release. The osteoinductivities of BMP2-CS-Ti, BMP2-Ti, CS-Ti and pristine Ti were examined by both in vitro cell tests and in vivo experiments. Bone marrow stem cell (BMSC) culture indicated that BMP2-CS-Ti is more potent in stimulating the differentiation of the adhering BMSC than the three other groups. Rabbit femur implantation revealed the excellent osteoinductivity of BMP2-CS-coated Ti implants. These results demonstrate that the BMP2-encapsulated CS coatings are stable osteoinductive coatings that realize the sustained release of BMP2 and maintain the activity of the protein.

  18. Deposition, structure, physical and invitro characteristics of Ag-doped β-Ca3(PO4)2/chitosan hybrid composite coatings on Titanium metal.

    Science.gov (United States)

    Singh, Ram Kishore; Awasthi, Sharad; Dhayalan, Arunkumar; Ferreira, J M F; Kannan, S

    2016-05-01

    Pure and five silver-doped (0-5Ag) β-tricalcium phosphate [β-TCP, β-Ca3(PO4)2]/chitosan composite coatings were deposited on Titanium (Ti) substrates and their properties that are relevant for applications in hard tissue replacements were assessed. Silver, β-TCP and chitosan were combined to profit from their salient and complementary antibacterial and biocompatible features.The β-Ca3(PO4)2 powders were synthesized by co-precipitation. The characterization results confirmed the Ag(+) occupancy at the crystal lattice of β-Ca3(PO4)2. The Ag-dopedβ-Ca3(PO4)2/chitosan composite coatings deposited by electrophoresis showed good antibacterial activity and exhibited negative cytotoxic effects towards the human osteosarcoma cell line MG-63. The morphology of the coatings was observed by SEM and their efficiency against corrosion of metallic substrates was determined through potentiodynamic polarization tests.

  19. Application of irradiated chitosan for fruit preservation

    Energy Technology Data Exchange (ETDEWEB)

    Lan, K.N. [Post-harvest Technology Institute, 4, Ngo Quyen-Ha Noi (Viet Nam); Lam, N.D. [Ha Noi Radiation Center, VAEC, 5T-160, Nghiado, Tuliem, Ha Noi (Viet Nam); Kume, Tamikazu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2000-03-01

    Preliminary test of mango (Mangifera indica) preservation by irradiated chitosan coating has been investigated. The coating by using irradiated chitosan in 1.5% solution has extended the shelf life of mango from 7 to 15 days. At the 15th day mango coated by irradiated chitosan has been keeping good color, natural ripening, without spoilage, weight loss 10%, whereas the mango without coating was spoiled completely and the coating of fruit with unirradiated chitosan inhibited the ripening. (author)

  20. Synthesis and Characterization of Chitosan-Coated Near-Infrared (NIR Layered Double Hydroxide-Indocyanine Green Nanocomposites for Potential Applications in Photodynamic Therapy

    Directory of Open Access Journals (Sweden)

    Pei-Ru Wei

    2015-09-01

    Full Text Available We designed a study for photodynamic therapy (PDT using chitosan coated Mg–Al layered double hydroxide (LDH nanoparticles as the delivery system. A Food and Drug Administration (FDA approved near-infrared (NIR fluorescent dye, indocyanine green (ICG with photoactive properties was intercalated into amine modified LDH interlayers by ion-exchange. The efficient positively charged polymer (chitosan (CS coating was achieved by the cross linkage using surface amine groups modified on the LDH nanoparticle surface with glutaraldehyde as a spacer. The unique hybridization of organic-inorganic nanocomposites rendered more effective and successful photodynamic therapy due to the photosensitizer stabilization in the interlayer of LDH, which prevents the leaching and metabolization of the photosensitizer in the physiological conditions. The results indicated that the polymer coating and the number of polymer coats have a significant impact on the photo-toxicity of the nano-composites. The double layer chitosan coated LDH–NH2–ICG nanoparticles exhibited enhanced photo therapeutic effect compared with uncoated LDH–NH2–ICG and single layer chitosan-coated LDH–NH2–ICG due to the enhanced protection to photosensitizers against photo and thermal degradations. This new class of organic-inorganic hybrid nanocomposites can potentially serve as a platform for future non-invasive cancer diagnosis and therapy.

  1. Study on the bonding strength between calcium phosphate/chitosan composite coatings and a Mg alloy substrate

    Science.gov (United States)

    Zhang, Jie; Dai, Chang-Song; Wei, Jie; Wen, Zhao-Hui

    2012-11-01

    In order to improve the bonding strength between calcium phosphate/chitosan composite coatings and a micro-arc oxidized (MAO)-AZ91D Mg alloy, different influencing parameters were investigated in the process of electrophoretic deposition (EPD) followed by conversion in a phosphate buffer solution (PBS). Surface morphology and phase constituents of the as-prepared materials were investigated by using X-ray diffractometer (XRD), Fourier-transformed infrared spectrophotometer (FTIR), Raman spectrometer, scanning electron microscope (SEM) with an energy dispersive spectrometer (EDS), and a thermo gravimetric and differential thermal analyzer (TG-DTA). Scratch tests were carried out to study the bonding properties between the coatings and the substrates. In vitro immersion tests were conducted to determine the corrosion behaviors of samples with and without deposit layers through electrochemical experiments. In the EPD process, the acetic acid content in the electrophoresis suspension and the electrophoretic voltage played important roles in improving the bonding properties, while the contents of chitosan (CS) and nano-hydroxyapatite (nHA, Ca10(PO4)6(OH)2) in the suspension had less significant influences on the mechanical bonding strength. It was observed that the coatings showed the excellent bonding property when an electrophoretic voltage was in a range of 40-110 V with other reagent amounts as follows: acetic acid: 4.5 vol.%, CS ≤ 0.25 g, nHA ≤ 2.0 g in 200 ml of a CS-acetic acid aqueous solution and nHA ≤ 2.5 g in 300 ml of absolute ethanol. The morphology of the composite coating obtained under the above optimal condition had a flake-like crystal structure. The EPD in the nHA/CS-acetic acid/ethanol suspension resulted in hydroxyapatite, chitosan, brushite (DCPD, CaHPO4·2H2O) and Ca(OH)2 in the coatings. After the as-prepared coating materials were immersed into PBS, Ca(OH)2 could be converted into HA and DCPD. The results of the electrochemical tests

  2. Morphology characterization and biocompatibility study of PLLA (Poly-L-Llactid-Acid) coating chitosan as stent for coronary heart disease

    Science.gov (United States)

    Widiyanti, Prihartini; Paramadini, Adanti W.; Jabbar, Hajria; Fatimah, Inas; Nisak, Fadila N. K.; Puspitasari, Rahma A.

    2016-03-01

    Cardiovascular disease is a global disease with high urgency. In the severe case of coronary heart disease while a blockage in the coronary arteries reach 75% or more, the patient required stent implantation. Stents are made of metal which has many limitations that can lead to blood clots and stent incompatibility toward the size of the blood vessels. There is a metal stent replacement solution that made from polymer material which is biocompatible. PLLA also has biocompatibility and good mechanical strength. PLLA stent will be coated with chitosan as a candidate for drug-coated stents which is able to work as a drug carrier. The aim of this study is to know the morphology information and biocompability status of PLLA coating chitosan as candidate of heart stent. Morphological results using SEM showed a smooth surface structure which reinforced clinical standard of stent material. Results of cytotoxicity test by MTT Assay method showed that the result of four samples in this experiment living cells is reached 90% which is non toxic and safe to use in the human body. %). The conclusion of this study is PLLA is polymer has potency to be used as stent material.

  3. An iodine supplementation of tomato fruits coated with an edible film of the iodide-doped chitosan.

    Science.gov (United States)

    Limchoowong, Nunticha; Sricharoen, Phitchan; Techawongstien, Suchila; Chanthai, Saksit

    2016-06-01

    In general, the risk of numerous thyroid cancers inevitably increases among people with iodine deficiencies. An iodide-doped chitosan (CT-I) solution was prepared for dipping tomatoes to coat the fresh surface with an edible film (1.5 μm), thereby providing iodine-rich fruits for daily intake. Characterisation of the thin film was conducted by FTIR and SEM. Stability of the CT-I film was studied via water immersion at various time intervals, and no residual iodide leached out due to intrinsic interactions between the cationic amino group of chitosan and iodide ions. Moreover, the iodide supplement exhibited no effect on the antioxidant activity of tomatoes. The iodine content in the film-coated tomato was determined by ICP-OES. The tomato coating with 1.5% (w/v) CT-I contained approximately 0.4 μg iodide per gram fresh weight. In addition, the freshness and storability of iodine-doped tomatoes were also maintained for shelf-life concerns.

  4. Enhanced Antifungal Effect of Chitosan/Pepper Tree (Schinus molle Essential Oil Bionanocomposites on the Viability of Aspergillus parasiticus Spores

    Directory of Open Access Journals (Sweden)

    Ana Guadalupe Luque-Alcaraz

    2016-01-01

    Full Text Available Chitosan nanoparticles (CS and chitosan/pepper tree (Schinus molle essential oil (CS-EO bionanocomposites were synthesized by nanoprecipitation method and the in vitro antifungal activity against Aspergillus parasiticus spores was evaluated. The shape and size were evaluated by scanning electron microscopy (SEM and dynamic light scattering (DLS. The surface charge was determined by assessing the zeta potential and the inclusion of essential oil in bionanocomposites using Fourier transform infrared spectroscopy (FT-IR. The effect on cell viability of the fungus was evaluated using the XTT technique and morphometric analysis by image processing. SEM and DLS analysis indicated that spherical particles with larger diameters for CS-EO biocomposites were observed. Zeta potential values were higher (+11.1 ± 1.60 mV for CS nanoparticles. Results suggest a chemical interaction between chitosan and pepper tree essential oil. The highest concentration of CS-EO complex caused a larger (40–50% decrease in A. parasiticus viability. The inclusion of pepper tree oil in CS nanoparticles is a feasible alternative to obtain antifungal biocomposites, where the activity that each compound presents individually is strengthened.

  5. Synthesis and characterization of the superparamagnetic iron oxide nanoparticles modified with cationic chitosan and coated with silica shell

    Energy Technology Data Exchange (ETDEWEB)

    Lewandowska-Łańcucka, Joanna, E-mail: lewandow@chemia.uj.edu.pl [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow (Poland); Staszewska, Magdalena; Szuwarzyński, Michał; Kępczyński, Mariusz [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow (Poland); Romek, Marek [Department of Cytology and Histology, Institute of Zoology, Jagiellonian University, Gronostajowa 9, 30-387 Krakow (Poland); Tokarz, Waldemar [Department of Solid State Physics, AGH University of Science and Technology, al. A. Mickiewicza 30, 30-059 Krakow (Poland); Szpak, Agnieszka; Kania, Gabriela; Nowakowska, Maria [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow (Poland)

    2014-02-15

    Highlights: • The new, facile methodology for synthesis of silica covered SPIONs is proposed. • The SPIONs was modified with cationic chitosan and coated with silica shell. • Negatively charged, rounded in shape particles of ca. 330 nm were obtained. • The product exhibits the superparamagnetic properties. • The product properties imply its potential applications in biomedicine areas. -- Abstract: Novel method for synthesis of superparamagnetic iron oxide nanoparticles (SPION) modified with a cationic chitosan (CCh) and coated with a silica shell, SPION-CCh-SiO{sub 2} was developed. The process was carried out in two steps. In the first step the chitosan coated SPIONs were obtained by co-precipitation of Fe{sup 2+} and Fe{sup 3+} with ammonium hydroxide in aqueous solution of CCh. In the second one, the silica shell is formed on their surfaces. The formation of SPION-CCh-SiO{sub 2} was achieved by direct decomposition of tetraethoxysilane (TEOS) adsorbed on a surface of SPION-CCh dispersed in aqueous phase under sonication and mechanical stirring at room temperature. The chemical composition and physicochemical properties of the materials were determined using X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Dynamic Light Scattering (DLS) and zeta potential measurements. The morphology of the particles was evaluated by Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM). Magnetic properties were confirmed using Atomic Force Microscopy/Magnetic Force Microscopy (AFM/MFM) and magnetization measurements. The resulting products are negatively charged, rounded in shape and exhibit the superparamagnetic properties what implies their potential applications in engineering and biomedicine areas.

  6. Thermo-therapeutic applications of chitosan- and PEG-coated NiFe2O4 nanoparticles

    Science.gov (United States)

    Manjura Hoque, S.; Tariq, Mehrin; Liba, S. I.; Salehin, F.; Mahmood, Z. H.; Khan, M. N. I.; Chattopadhayay, K.; Islam, Rafiqul; Akhter, S.

    2016-07-01

    The paper reports the thermo-therapeutic applications of chitosan- and PEG-coated nickel ferrite (NiFe2O4) nanoparticles. In this study NiFe2O4 nanoparticles were synthesized by the co-precipitation method, tuning the particle size through heat treatment in the temperature range from 200-800 °C for 3 h. XRD and TEM analysis revealed that the the ultrafine nanoparticles were of size 2-58 nm. Crystallinity of the NiFe2O4 nanoparticles in the as-dried condition with the particle size ˜2-3 nm was confirmed from the presence of a lattice fringe in the HRTEM image. VSM measurements showed that a superparamagnetic/ferromagnetic transition occurs with increasing particle size, which was further confirmed by Mössbauer spectroscopy. The nickel ferrite nanoparticles with optimum particle size of 10 nm were then coated with materials commonly used for biomedical applications, i.e. chitosan and PEG, to form homogeneous suspensions. The hydrodynamic diameter and the polydispersity index (PDI) were analyzed by dynamic light scattering at the physiological temperature of 37 °C and found to be 187 nm and 0.21 for chitosan-coated nanoparticles and 285 nm and 0.32 for PEG-coated ones. The specific loss power of rf induction heating by the set-up for hyperthermia and r 2 relaxivity by the nuclear magnetic resonance were determined. The results of induction heating measurements showed that the temperature attained by the nanoparticles of size 10 nm and concentration of about 20 mg ml-1 was >70 °C (for chitosan) and >64 °C (for PEG). It has been demonstrated that the required temperature for hyperthermia heating could be tuned by tuning the particle size, shape and magnetization and the concentration of solution. For other potential biomedical applications of the NiFe2O4 nanoparticle solution, e.g. magnetic resonance imaging, the NMR studies yielded the T 1 and T 2 relaxivities as 0.348 and 89 mM-1 s-1 respectively. The fact that the T 2 relaxivity is orders of magnitude higher

  7. Quaternized chitosan-coated nanofibrous materials containing gossypol: preparation by electrospinning, characterization and antiproliferative activity towards HeLa cells.

    Science.gov (United States)

    Ignatova, Milena; Manolova, Nevena; Toshkova, Reneta; Rashkov, Iliya; Gardeva, Elena; Yossifova, Liliya; Alexandrov, Marin

    2012-10-15

    Nanofibrous polylactide-based materials loaded with a natural polyphenolic compound gossypol (GOS) with antitumor properties were prepared by electrospinning. The nanofibrous materials were coated with a thin film of crosslinked quaternized chitosan (QCh). GOS incorporated in the nanofibrous mats was in the amorphous state. GOS release was diffusion-controlled and its in vitro release profiles depended on the mat composition. The nanofibrous materials exhibited high cytotoxicity towards HeLa tumor cells. Interestingly, it was particularly pronounced in the case of fibrous materials, which contain both QCh and GOS. The observed strong antiproliferative effect of the nanofibrous mats was mainly due to induction of cell apoptosis.

  8. The effect of a PEG versus a chitosan coating on the interaction of drug colloidal carriers with the ocular mucosa.

    Science.gov (United States)

    De Campos, Angela M; Sánchez, Alejandro; Gref, Ruxandra; Calvo, Pilar; Alonso, María J

    2003-09-01

    The influence of the surface characteristics of colloidal drug carriers in their interaction with different biological surfaces is becoming increasingly evident. In order to investigate the importance of these characteristics in their interaction with the ocular mucosa, we developed three types of nanocapsules that differ in their surface properties: poly- epsilon -caprolactone (PECL) nanocapsules, chitosan (CS)-coated PECL nanocapsules and poly(ethylene glycol) (PEG)-coated PECL nanocapsules. Two different approaches were used to form these polymer coated nanocapsules: (i) the electrostatic anchorage of the coating onto the PECL nanocapsules-in the case of CS-and (ii) the use of the previously synthesized copolymer PECL-PEG for the formation of the nanocapsules. In both cases, the systems, prepared by the interfacial deposition technique, were loaded with a fluorescent dye (rhodamine) in order to quantify and visualize their interaction with the ocular surface ex vivo and in vivo. An important conclusion from the ex vivo studies is that the developed systems, and specially the CS-coated ones, enhanced the penetration of the encapsulated dye through the cornea. This effect was not simple due to the physical presence of the nanocapsules but to their ability to carry the encapsulated compound. The second conclusion from the confocal laser scanning microscopy (CLSM) studies is that the systems were able to enter the corneal epithelium by a transcellular pathway and that the penetration rate was dependent on the coating composition. The images suggest that the PEG coating accelerates the transport of the nanocapsules across the whole epithelium, whereas the CS coating favours the retention of the nanocapsules in the superficial layers of the epithelium. The specific behaviour of CS-coated systems was also corroborated in vivo. These results indicate that the surface composition of colloidal drug carriers affects their biodistribution in the eye. Therefore, this surface

  9. Treatment of bleomycin-induced pulmonary fibrosis by inhaled tacrolimus-loaded chitosan-coated poly(lactic-co-glycolic acid) nanoparticles.

    Science.gov (United States)

    Lee, Changkyu; Seo, Jisoo; Hwang, Ha Shin; Thao, Le Quang; Lee, Seunghyun; Lee, Eun Seong; Lee, Eun Hee; Choi, Han-Gon; Youn, Yu Seok

    2016-03-01

    Pulmonary fibrosis is a chronic lung disease characterized by inflammation and collagen deposition, with an estimated mortality rate exceeding 70%. Here, we evaluated the therapeutic effectiveness of inhaled tacrolimus-loaded chitosan-coated poly(lactic-co-glycolic acid) nanoparticles (chitosan TAC PLGA-NPs) in a bleomycin-induced pulmonary fibrosis mouse model. Chitosan TAC PLGA-NPs were fabricated using an o/w emulsification diffusion method, and uncoated TAC PLGA-NPs and chitosan TAC PLGA-NPs were spherical with approximate diameters of 320 and 441 nm, respectively. The zeta potential of chitosan TAC PLGA-NPs (+13.6 mV) was increased significantly by chitosan-coating versus uncoated TAC PLGA-NPs (-28.3 mV). The incorporation efficiency of tacrolimus was 37.7%, and the tacrolimus was gradually released until about 5 day. Direct inhalation of chitosan TAC PLGA-NPs (TAC 180 μg/mouse) twice a week produced marked anti-fibrotic efficacy in mice with bleomycin-induced pulmonary fibrosis, which was much better than the efficacy resulting from daily oral administration (TAC 300 μg/mouse) on the basis of hematoxylin/eosin and Masson's trichrome staining assessments. Imaging of lung deposition showed that chitosan TAC PLGA-NPs were located well in the lungs and gradually faded over 96 h. The pulmonary delivery of tacrolimus could be therapeutically efficacious for treating pulmonary fibrosis. TAC-loaded PLGA nanoparticles should be considered to be an efficient sustained-release type inhalation system that reduces administration frequency and relevant side effects.

  10. Preparation and characterization of chitosan/cashew gum beads loaded with Lippia sidoides essential oil

    Energy Technology Data Exchange (ETDEWEB)

    Paula, Haroldo C.B., E-mail: hpaula@ufc.br [Department of Analytical and Physical Chemistry, Federal University of Ceara, UFC, Fortaleza-CE (Brazil); Sombra, Fernanda Matoso; Cavalcante, Rafaela de Freitas; Abreu, Flavia O.M.S. [Department of Analytical and Physical Chemistry, Federal University of Ceara, UFC, Fortaleza-CE (Brazil); Paula, Regina C.M. de [Department of Organic and Inorganic Chemistry, Federal University of Ceara, UFC, Fortaleza-CE (Brazil)

    2011-03-12

    Beads based on chitosan (CH) and cashew gum (CG), were prepared and loaded with an essential oil with larvicide activity (Lippia sidoides - Ls). CH and CH-CG beads were characterized by scanning electron microscopy (SEM), infrared and UV-VIS spectroscopy, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), as well as, regarding their larvicide loading, swelling, in vitro and in vivo release kinetics. The oil encapsulation was evidenced by FTIR analysis and LS loading ranges from 2.4% to 4.4%. CH beads duly showed swelling degree (Q) values from 4.0 to 6.7, reaching equilibrium after 30 min, whereas crosslinked CH-CG beads showed lower swelling values, from 0.4 to 3.8, exhibiting a longer equilibrium time. Liquid transport parameters have revealed diffusion coefficient for CH-CG beads, as low as 2 x 10{sup -15} m{sup 2}/s. TGA and DSC revealed that CH:CG crosslinked beads are more thermally stable than CH beads. In vitro release follows a non-Fickian diffusion profile for both bead types, however, and a prolonged release being achieved only after beads crosslinking. In vivo release showed that both CH and CH-CG presented a prolonged larvicide effect. These aforesaid results, indicate that CH-CG beads loaded with LS are efficient for A. aegypti larval control.

  11. Development of a chitosan based double layer-coated tablet as a platform for colon-specific drug delivery

    Directory of Open Access Journals (Sweden)

    Kim MS

    2016-12-01

    Full Text Available Min Soo Kim,1,* Dong Woo Yeom,1,* Sung Rae Kim,1 Ho Yub Yoon,1 Chang Hyun Kim,1 Ho Yong Son,1 Jin Han Kim,1 Sangkil Lee,2 Young Wook Choi1 1College of Pharmacy, Chung-Ang University, Seoul, 2College of Pharmacy, Keimyung University, Daegu, South Korea *These authors contributed equally to this work Abstract: A double layer-coated colon-specific drug delivery system (DL-CDDS was developed, which consisted of chitosan (CTN based polymeric subcoating of the core tablet containing citric acid for microclimate acidification, followed by an enteric coating. The polymeric composition ratio of Eudragit E100 and ethyl cellulose and amount of subcoating were optimized using a two-level factorial design method. Drug-release characteristics in terms of dissolution efficiency and controlled-release duration were evaluated in various dissolution media, such as simulated colonic fluid in the presence or absence of CTNase. Microflora activation and a stepwise mechanism for drug release were postulated. Consequently, the optimized DL-CDDS showed drug release in a controlled manner by inhibiting drug release in the stomach and intestine, but releasing the drug gradually in the colon (approximately 40% at 10 hours and 92% at 24 hours in CTNase-supplemented simulated colonic fluid, indicating its feasibility as a novel platform for CDD. Keywords: chitosan, colon-specific delivery, acidification, microflora, factorial design, controlled release

  12. O/W型茶树精油壳聚糖乳化膜材料的制备%Preparation of O/W chitosan-based tea tree essential oil emulsive film material

    Institute of Scientific and Technical Information of China (English)

    葛彦; 葛明桥

    2014-01-01

    以壳聚糖为基材,利用表面活性剂吐温80包覆茶树精油形成乳液,采用铸膜法制备 O/W 型茶树精油壳聚糖乳化膜,运用扫描电镜、红外光谱仪等对膜的结构特征和性能进行表征.结果表明,茶树精油被吐温80包覆,在壳聚糖溶液中形成稳定的 O/W乳液型铸膜液,成膜后茶树精油微粒呈球形,直径约为1μm.性能测试结果表明,茶树精油的添加大大提高了壳聚糖膜的抑菌效果,该膜具有较好的舒适性、吸水性、透气性和抑菌性,有望将来成为一种新型的医用材料.%Tea tree essential oil was coated with Tween 80 as surfactant to form an emulsion.Chitosan was used for the substrate and O/W chitosan-based tea tree essential oil emulsive film was prepared with cast method. Scanning electron microscopy,infrared spectroscopy,etc.were used to characterize the film’s structural feature and performance.The results showed that tea tree essential oil in chitosan solution was coated by Tween 80 to form a stable O/W emulsion casting solution.The particles of tea tree essential oil were in spherical form with a diameter of about 1μm in the film.The results of performance test indicated that the addition of tea tree es-sential oil greatly enhanced antibacterial effect of chitosan film.Film had good conformability,water absorp-tion,permeability and antibacterial property so that it was expected to be a new type of medical material in the future.

  13. Effects of anti-CD44 monoclonal antibody IM7 carried with chitosan polylactic acid-coated nano-particles on the treatment of ovarian cancer

    Science.gov (United States)

    Yang, Yizhuo; Zhao, Xinghui; Li, Xiuli; Yan, Zhifeng; Liu, Zhongyu; Li, Yali

    2017-01-01

    Failure in early diagnosis and ineffective treatment are the major causes of ovarian cancer mortality. Hyaluronan and its receptor, cluster of differentiation (CD)44, have been considered to be valid targets for treating cancer. The anti-CD44 monoclonal antibody IM7 is effective in treating ovarian cancer; however, its toxicity should not be ignored. The present study has developed a new drug carrier system composed of chitosan nano-particles coated with polylactic acid (PLA) to improve the treatment efficacy and reduce toxicity. An ionic crosslinking method and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride/N-hydroxysuccinimide were used to prepare the IM7 antibody, which was loaded with chitosan nano-particles. The surfaces of the nano-particles were coated with PLA to generate PLA-chitosan-IM7. Subsequently, transmission electron microscopy (TEM) was used to observe the size and zeta potential of the nano-particles. In addition, a spectrophotometer was used to calculate the loading rate and release rate of the nano-particles in acidic and neutral environments. MTT assay was used to evaluate the anti-proliferative effect of PLA-chitosan-IM7 on the human ovarian cancer cell line HO-8910PM. In addition, an in vivo imaging system was used to further investigate the effect of PLA-chitosan-IM7 on the treatment of mice with ovarian cancer. A total of 35 days subsequent to PLA-chitosan-IM7 treatment, all animals were sacrificed by CO2, and the tumors were removed and weighted. The PLA-chitosan-IM7 nano-particles were successfully prepared, since TEM revealed that their size was 300–400 nm and their zeta potential was +25 mV. According to the spectrophotometry results, the loading rate was 52%, and PLA-chitosan-IM7 exhibited good resistance to acids. MTT assay demonstrated that PLA-chitosan-IM7 could suppress the proliferation of HO-8910PM cells in vitro. The in vivo imaging system revealed that PLA-chitosan-IM7 was effective in controlling the

  14. Thermodynamic Insights and Conceptual Design of Skin-Sensitive Chitosan Coated Ceramide/PLGA Nanodrug for Regeneration of Stratum Corneum on Atopic Dermatitis.

    Science.gov (United States)

    Jung, Sang-Myung; Yoon, Gwang Heum; Lee, Hoo Chul; Jung, Moon Hee; Yu, Sun Il; Yeon, Seung Ju; Min, Seul Ki; Kwon, Yeo Seon; Hwang, Jin Ha; Shin, Hwa Sung

    2015-12-15

    Atopic dermatitis (AD) is a complex skin disease primarily characterized by psoriasis of the stratum corneum. AD drugs have usually been used in acidic and hydrophilic solvents to supply moisture and prevent lipid defects. Ceramide is a typical treatment agent to regenerate the stratum corneum and relieve symptoms of AD. However, ceramide has limitation on direct use for skin because of its low dispersion properties in hydrophilic phase and side effects at excessive treatment. In this study, ceramide imbedded PLGA nanoparticles were developed with chitosan coating (Chi-PLGA/Cer) to overcome this problem. The chitosan coating enhanced initial adherence to the skin and prevented the initial burst of ceramide, but was degraded by the weakly acidic nature of skin, resulting in controlled release of ceramide with additional driving force of the squeezed PLGA nanoparticles. Additionally, the coating kinetics of chitosan were controlled by manipulating the reaction conditions and then mathematically modeled. The Chi-PLGA/Cer was not found to be cytotoxic and ceramide release was controlled by pH, temperature, and chitosan coating. Finally, Chi-PLGA/Cer was demonstrated to be effective at stratum corneum regeneration in a rat AD model. Overall, the results presented herein indicated that Chi-PLGA/Cer is a novel nanodrug for treatment of AD.

  15. A Green Route for Substrate-Independent Oil-Repellent Coatings

    Science.gov (United States)

    Xu, Li-Ping; Han, Da; Wu, Xiuwen; Zhang, Qingqing; Zhang, Xueji; Wang, Shutao

    2016-11-01

    Oil repellent surface have lots of practical applications in many fields. Current oil repellent coating may suffer from limited liquid repellency to oils or environmental risks. In this work, we report an eco-friendly ‘green’ processes for preparing oil-repellent surface using a renewable and environmentally benign bioresource alginate. The oil-repellent coating was prepared by a two-step surface coating technique and showed stable oil repellency to many kinds of oils. The fabrication process was very simple with no need for special equipment, and this approach can be successfully employed to various substrates with different compositions, sizes and shapes, or even substrate-independent oil-repellent materials. The as-prepared coating of calcium alginate may have a good future in packaging oil-containing products and foods.

  16. Substrate-Independent, Transparent Oil-Repellent Coatings with Self-Healing and Persistent Easy-Sliding Oil Repellency.

    Science.gov (United States)

    Yu, Li; Chen, George Y; Xu, Haolan; Liu, Xiaokong

    2016-01-26

    Herein we report a simple and substrate-independent approach to fabricate transparent oil-repellent coatings, which involves alternate deposition of poly(diallyldimethylammonium) (PDDA) and poly(styrenesulfonate) (PSS) onto substrates, followed by incubation of the coated objects into perfluorooctanoate (PFO) aqueous solutions for 2 min. Various low-surface-tension liquids can easily slide down the coating surfaces on flat substrates at a sliding angle lower than 12° for 10 μL droplets. The coatings are applicable to different substrates including Si, glass, plastic, steel, and wood, and those with complex shapes and large surface areas. They are also applicable to rough substrates with roughness at both micro/nanoscale and macroscopic scales to realize the easy-sliding oil repellency. Incubation of the PDDA/PSS polyelectrolyte multilayers (PEMs) into PFO solutions induces an effective but nondestructive substitution of PFO anions for PSS in the PEMs, which results in a composite coating with PFO anions homogeneously interspersed in both the coating surface and the bulk. Thanks to the as-described "repeating-layer" composition/structure of the coatings, their easy-sliding oil repellency can be self-healed after surface decomposition or well maintained after physical damages, due to the replenishing surface. Therefore, the advantageous characteristics of the as-developed oil-repellent coatings and the simplicity of the preparation protocol make the coatings highly practical for real-world applications. It is believed that the coatings can perform as antismudge coatings that shield against oil-borne contaminants, chemical-shield coatings that protect coated plastics from dissolution by organic solvents, and nonstick coatings (of oil tankers or pipelines) that enable loss-free oil transportation.

  17. Maize seed coatings and seedling sprayings with chitosan and hydrogen peroxide: their influence on some phenological and biochemical behaviors

    Science.gov (United States)

    Lizárraga-Paulín, Eva-Guadalupe; Miranda-Castro, Susana-Patricia; Moreno-Martínez, Ernesto; Lara-Sagahón, Alma-Virginia; Torres-Pacheco, Irineo

    2013-01-01

    Objective: To evaluate the effect of chitosan (CH) and hydrogen peroxide (H2O2) seed coatings and seedling sprinklings on two different maize varieties by measuring their phenology, the H2O2 presence, the catalase (CAT) activity, and the protein quantity. Methods: Seven groups of ten seeds for each maize variety were treated with CH (2% (20 g/L) and 0.2% (2 g/L)) or H2O2 (8 mmol/L) by coating, sprinkling, or both. Germination and seedling growth were measured. One month after germination, the presence of H2O2 in seedlings in the coated seed treatments was evaluated. Protein content and CAT activity were determined under all treatments. Results: H2O2 seed coating enhanced the germination rate and increased seedling and stem length in the quality protein maize (QPM) variety. Seedlings had a higher emergence velocity under this treatment in both varieties. CH and H2O2 sprinklings did not have an effect on seedling phenology. Exogenous application of H2O2 promoted an increase of endogenous H2O2. CH and H2O2 seedling sprinkling increased the protein content in both maize varieties, while there was no significant effect on the CAT activity of treated seeds and seedlings. Conclusions: CH and H2O2 enhance some phenological and biochemical features of maize depending on their method of application. PMID:23365007

  18. Antibacterial, antioxidant and optical properties of edible starch-chitosan composite film containing Thymus kotschyanus essential oil

    Directory of Open Access Journals (Sweden)

    Tooraj Mehdizadeh

    2012-09-01

    Full Text Available Thyme Essential oils (EO with antimicrobial and antioxidant properties are widely used in pharmaceutical, cosmetic, and perfume industry. It is also used for flavoring and preservation of several foods. Nowadays, packaging research is receiving a considerable attention due to the development of eco-friendly materials made from natural polymers such as starch and chitosan. In this study Thymus kotschyanus EO concentrations ranging from 0 to 2.0%, incorporated in starch-chitosan composite (S-CH film were used. Antimicrobial and antioxidant properties significantly increased with the incorporation of EO (p < 0.05. Incorporating EO, increased total color differences (DE, yellowness index (YI and whiteness index (WI which were significantly higher than control and its transparency was reduced. Our results pointed out that the incorporation of Thymus kotschyanus EO as a natural antibacterial agent has potential for using the developed film as an active packaging.

  19. Matrix Effect on the Spray Drying Nanoencapsulation of Lippia sidoides Essential Oil in Chitosan-Native Gum Blends.

    Science.gov (United States)

    Paula, Haroldo C B; Oliveira, Erick F; Carneiro, Maria J M; de Paula, Regina C M

    2016-05-25

    Essential oils have many applications in the pharmaceutical, chemical, and food fields, however, their use is limited to the fact that they are very labile, requiring their a priori encapsulation, aiming to preserve their properties.This work reports on the preparation of chitosan-gum nanoparticles loaded with thymol containing Lippia sidoides essential oil, using exudates of Anacardium Occidentale (cashew gum), Sterculia striata (chichá gum), and Anadenanthera macrocarpa trees (angico gum). Nanoparticles were produced by spray drying an emulsion of L. sidoides essential oil and aqueous solution of gums with different chitosan : gum ratios. Samples were characterized by FTIR and UV/VIS spectroscopy, particle size, volume distribution, and zeta potential. The FTIR spectrum showed the main signals of chitosan and the gums. Data obtained revealed that the samples had sizes in the nano range, varying from 17 nm to 800 nm. The zeta potential varied from + 30 mV to - 40 mV. Nanoparticle loading values varied from 6.7 % to 15.6 %, with an average encapsulating efficiency of 62 %, where the samples with high ratios of cashew gum and chichá gum presented high oil loading values. The data revealed that both the chitosan : gum ratio and polysaccharide characteristics play major roles in nanoencapsulation processes.

  20. Pharmacodynamics study of zedoary turmeric oil chitosan microspheres administered via arterial embolization.

    Science.gov (United States)

    Song, Tian; Sun, Rongyue

    2016-12-01

    Zedoary turmeric oil, a plant extract currently in clinical use, may provide potent pharmacological actions such as liver injury. In the previous study, to improve the in vivo absorption of ZTO and produce a high oral bioavailability, chitosan was employed to prepare sustained-release microspheres containing ZTO. In this study, a portability liver cancer model of rats was established successfully to compare the pharmacodynamic of ZTO microspheres and injection. In vitro results showed that microspheres had almost uniformly spherical shapes and were well dispersed by a relatively dynamic stable system. In vivo, compared with the control group, all ZTO microspheres groups resulted in growing inhibition of walker-256 cells transplanted solid tumor and the obvious controlled tumor size. At the same dose, ZTO microspheres suggested a better effect. The data showed that three doses of ZTO microspheres could prolong the average survival time considerably. None of the severe signs such as the pimelosis, fibrotic changes and fibrous septum were detected in the histopathology study.

  1. Physicochemical and Antioxidant Properties of Chitosan Films Incorporated with Cinnamon Oil

    Directory of Open Access Journals (Sweden)

    Marco A. López-Mata

    2015-01-01

    Full Text Available Chitosan films (CF with cinnamon bark oil (CO incorporated at 0% (control, 0.25%, 0.5%, and 1.0% v/v were prepared by an emulsion method. The films were characterized based on their physical properties (solubility, water vapor permeability, optical property, and microstructure and antioxidant properties (DPPH, ABTS, and its protective effects on human erythrocytes. The results showed that the incorporation of 0.5 and 1.0% of CO into the CF significantly decreased its solubility to 22% of the control (p<0.05. The water vapor permeability of the CF-CO was significantly reduced to 40% with low concentrations of CO (0.25% incorporated into the CF. In general, the films presented a yellow coloration and an increase in transparency with the incorporation of CO into the CF. It was also observed that the incorporation of CO increased the antioxidant activity between 6.0-fold and 14.5-fold compared to the control, and the protective capacity against erythrocyte hemolysis increased by as much as 80%.

  2. The Coated-Wire Ion Selective Electrode (CWISE of Chromate Using PVC-Membrane Based on Chitosan as A Carrier

    Directory of Open Access Journals (Sweden)

    Dedeh Kurniasih

    2012-10-01

    Full Text Available A coated-wire ion selective electrode (CWISE based on chitosan as a carrier for detection of chromate, was developed. CWISE has easy measurement for field analysis, good selectivity and sensitivity. The CWISE’s membrane consist of mixture an active material of chitosan, aliquat 336-chromate, polyvinylchloride (PVC and dioctylphtalate (DOP as plasticizer = 4:0.5:35:60.5 (% w/w dissolved in tetrahydrofuran (THF solvent (1:3 w/v. The electrode exhibited a good Nernstian slope of 29.77±0.03 mV/decade and a linear concentration range from 10-6 to 10-1 M for chromate. The limit of detection was 1.862 x 10-6 M. It had response time of 20 – 40 sec, and could be used for 49 days. This chromate selective-electrode was found more selective towards the chromate ion than other anions, useable in pH range of 5.0 – 9.0 and temperature of 20 – 50 oC. It was applied as an electrode for direct determination of chromate in water samples and their result compared to standard spectrophotometric method.

  3. Surface functionalization of chitosan-coated magnetic nanoparticles for covalent immobilization of yeast alcohol dehydrogenase from Saccharomyces cerevisiae

    Energy Technology Data Exchange (ETDEWEB)

    Li Guiyin [Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha, Hunan 410078 (China); Biomedical Engineering Research Centre of Guilin University of Electronic Technology, Guilin, Guangxi 541014 (China); Zhou Zhide [Biomedical Engineering Research Centre of Guilin University of Electronic Technology, Guilin, Guangxi 541014 (China); Li Yuanjian, E-mail: yuan_jianli@yahoo.co [Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha, Hunan 410078 (China); Huang Kelong, E-mail: klhuang@mail.csu.edu.c [College of Chemistry and Chemical Engineering, Central South University, Changsha, Hunan 410083 (China); Zhong Ming [College of Chemistry and Chemical Engineering, Central South University, Changsha, Hunan 410083 (China)

    2010-12-15

    A novel and efficient immobilization of yeast alcohol dehydrogenase (YADH, EC1.1.1.1) from Saccharomyces cerevisiae has been developed by using the surface functionalization of chitosan-coated magnetic nanoparticles (Fe{sub 3}O{sub 4}/KCTS) as support. The magnetic Fe{sub 3}O{sub 4}/KCTS nanoparticles were prepared by binding chitosan alpha-ketoglutaric acid (KCTS) onto the surface of magnetic Fe{sub 3}O{sub 4} nanoparticles. Later, covalent immobilization of YADH was attempted onto the Fe{sub 3}O{sub 4}/KCTS nanoparticles. The effect of various preparation conditions on the immobilized YADH process such as immobilization time, enzyme concentration and pH was investigated. The influence of pH and temperature on the activity of the free and immobilized YADH using phenylglyoxylic acid as substrate has also been studied. The optimum reaction temperature and pH value for the enzymatic conversion catalyzed by the immobilized YADH were 30 {sup o}C and 7.4, respectively. Compared to the free enzyme, the immobilized YADH retained 65% of its original activity and exhibited significant thermal stability and good durability.

  4. Surface functionalization of chitosan-coated magnetic nanoparticles for covalent immobilization of yeast alcohol dehydrogenase from Saccharomyces cerevisiae

    Science.gov (United States)

    Li, Gui-yin; Zhou, Zhi-de; Li, Yuan-jian; Huang, Ke-long; Zhong, Ming

    2010-12-01

    A novel and efficient immobilization of yeast alcohol dehydrogenase (YADH, EC1.1.1.1) from Saccharomyces cerevisiae has been developed by using the surface functionalization of chitosan-coated magnetic nanoparticles (Fe 3O 4/KCTS) as support. The magnetic Fe 3O 4/KCTS nanoparticles were prepared by binding chitosan alpha-ketoglutaric acid (KCTS) onto the surface of magnetic Fe 3O 4 nanoparticles. Later, covalent immobilization of YADH was attempted onto the Fe 3O 4/KCTS nanoparticles. The effect of various preparation conditions on the immobilized YADH process such as immobilization time, enzyme concentration and pH was investigated. The influence of pH and temperature on the activity of the free and immobilized YADH using phenylglyoxylic acid as substrate has also been studied. The optimum reaction temperature and pH value for the enzymatic conversion catalyzed by the immobilized YADH were 30 °C and 7.4, respectively. Compared to the free enzyme, the immobilized YADH retained 65% of its original activity and exhibited significant thermal stability and good durability.

  5. Chitosan coatings onto polyethylene terephthalate for the development of potential active packaging material

    Energy Technology Data Exchange (ETDEWEB)

    Zemljic, Lidija Fras, E-mail: lidija.fras@uni-mb.si [Laboratory for Characterization and Processing of Polymers, Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, 2000 Maribor (Slovenia); Tkavc, Tina [Laboratory for Characterization and Processing of Polymers, Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, 2000 Maribor (Slovenia); Vesel, Alenka [Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Sauperl, Olivera [Laboratory for Characterization and Processing of Polymers, Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, 2000 Maribor (Slovenia)

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer The adsorption/desorption of chitosan onto PET plastic film was studied. Black-Right-Pointing-Pointer Chitosan was reversible attached onto PET plastic films. Black-Right-Pointing-Pointer Antimicrobial functionalized PET may provide potential active packaging material. - Abstract: In this paper advanced surface treatment of PET plastic film is presented for introduction of antimicrobial properties as a potential application for food (as for example meat) packaging material. Adsorption/desorption of chitosan onto PET plastic film surface was studied using several analytical techniques such as: X-Ray Photoelectron Spectroscopy (XPS), ATR-FTIR spectroscopy and titrations. Kinetic desorption of chitosan from PET surface was analysed by polyelectrolyte titration and spectrophotometric Ninhydrine reaction. Standard antimicrobial test ASTM E2149-01 was performed for functionalised PET materials in order to determine their antimicrobial properties; i. e. to measure the reductions of some of the meat pathogens; such as bacteria Salmonella enterica, Campylobacter spp., Escherichia coli, Listeria monocytogenes and fungi Candida albicans.

  6. Dual drug loaded chitosan nanoparticles-sugar--coated arsenal against pancreatic cancer.

    Science.gov (United States)

    David, Karolyn Infanta; Jaidev, Leela Raghav; Sethuraman, Swaminathan; Krishnan, Uma Maheswari

    2015-11-01

    Pancreatic cancer is an aggressive form of cancer with poor survival rates. The increased mortality due to pancreatic cancer arises due to many factors such as development of multidrug resistance, presence of cancer stem cells, development of a stromal barrier and a hypoxic environment due to hypo-perfusion. The present study aims to develop a nanocarrier for a combination of drugs that can address these multiple issues. Quercetin and 5-fluorouracil were loaded in chitosan nanoparticles, individually as well as in combination. The nanoparticles were characterized for morphology, size, zeta potential, percentage encapsulation of drugs as well as their release profiles in different media. The dual drug-loaded carrier exhibited good entrapment efficiency (quercetin 95% and 5-fluorouracil 75%) with chitosan: quercetin: 5-fluorouracil in the ratio 3:1:2. The release profiles suggest that 5-fluorouracil preferentially localized in the periphery while quercetin was located towards the core of chitosan nanoparticles. Both drugs exhibited considerable association with the chitosan matrix. The dual drug-loaded carrier system exhibited significant toxicity towards pancreatic cancer cells both in the 2D as well as in the 3D cultures. We believe that the results from these studies can open up interesting options in the treatment of pancreatic cancer.

  7. Preparation, characterization, and in vitro and in vivo investigation of chitosan-coated poly (d,l-lactide-co-glycolide nanoparticles for intestinal delivery of exendin-4

    Directory of Open Access Journals (Sweden)

    Wang M

    2013-03-01

    Full Text Available Mengshu Wang,1* Yong Zhang,1* Jiao Feng,1 Tiejun Gu,1 Qingguang Dong,1 Xu Yang,2 Yanan Sun,1 Yongge Wu,1 Yan Chen,1 Wei Kong1 1National Engineering Laboratory for AIDS Vaccine, College of Life Science, Jilin University, Changchun, People’s Republic of China; 2BCHT Biopharm Co, Ltd, Changchun, People’s Republic of China*These authors contributed equally to this workBackground: Exendin-4 is an incretin mimetic agent approved for type 2 diabetes treatment. However, the required frequent injections restrict its clinical application. Here, the potential use of chitosan-coated poly (d,l-lactide-co-glycolide (CS-PLGA nanoparticles was investigated for intestinal delivery of exendin-4.Methods and results: Nanoparticles were prepared using a modified water–oil–water (w/o/w emulsion solvent-evaporation method, followed by coating with chitosan. The physical properties, particle size, and cell toxicity of the nanoparticles were examined. The cellular uptake mechanism and transmembrane permeability were performed in Madin-Darby canine kidney-cell monolayers. Furthermore, in vivo intraduodenal administration of exendin-4-loaded nanoparticles was carried out in rats. The PLGA nanoparticle coating with chitosan led to a significant change in zeta potential, from negative to positive, accompanied by an increase in particle size of ~30 nm. Increases in both the molecular weight and degree of deacetylation of chitosan resulted in an observable increase in zeta potential but no apparent change in the particle size of ~300 nm. Both unmodified PLGA and chitosan-coated nanoparticles showed only slight cytotoxicity. Use of different temperatures and energy depletion suggested that the cellular uptake of both types of nanoparticles was energy-dependent. Further investigation revealed that the uptake of PLGA nanoparticles occurred via caveolin-mediated endocytosis and that of CS-PLGA nanoparticles involved both macropinocytosis and clathrin-mediated endocytosis

  8. Fabrication and characterization of chitosan/OGP coated porous poly(ε-caprolactone) scaffold for bone tissue engineering.

    Science.gov (United States)

    Cui, Zhixiang; Lin, Luyin; Si, Junhui; Luo, Yufei; Wang, Qianting; Lin, Yongnan; Wang, Xiaofeng; Chen, Wenzhe

    2017-03-14

    As one of the stimulators on bone formation, osteogenic growth peptide (OGP) improves both proliferation and differentiation of the bone cells in vitro and in vivo. The aim of this work was the preparation of three dimensional porous poly(ε-caprolactone) (PCL) scaffold with high porosity, well interpore connectivity, and then its surface was modified by using chitosan (CS)/OGP coating for application in bone regeneration. In present study, the properties of porous PCL and CS/OGP coated PCL scaffold, including the microstructure, water absorption, porosity, hydrophilicity, mechanical properties, and biocompatibility in vitro were investigated. Results showed that the PCL and CS/OGP-PCL scaffold with an interconnected network structure have a porosity of more than 91.5, 80.8%, respectively. The CS/OGP-PCL scaffold exhibited better hydrophilicity and mechanical properties than that of uncoated PCL scaffold. Moreover, the results of cell culture test showed that CS/OGP coating could stimulate the proliferation and growth of osteoblast cells on CS/OGP-PCL scaffold. These finding suggested that the surface modification could be a effective method on enhancing cell adhesion to synthetic polymer-based scaffolds in tissue engineering application and the developed porous CS/OGP-PCL scaffold should be considered as alternative biomaterials for bone regeneration.

  9. Quaternized chitosan-coated nanofibrous implants loaded with gossypol prepared by electrospinning and their efficacy against Graffi myeloid tumor.

    Science.gov (United States)

    Ignatova, Milena; Kalinov, Kalin; Manolova, Nevena; Toshkova, Reneta; Rashkov, Iliya; Alexandrov, Marin

    2014-01-01

    Nanofibrous poly(L-lactide-co-D,L-lactide) (coPLA) or coPLA/poly(ethylene glycol) implants loaded with plant polyphenolic compound gossypol (GOS) with anti-tumor activity were fabricated by electrospinning. Implants containing quaternized chitosan (QCh) were prepared by coating of the obtained fibrous materials with a thin film of cross-linked QCh. The morphology of the implants and chemical composition of the implant surface were studied by means of scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). In vitro cytotoxicity assay showed that GOS-loaded nanofibrous implants, both non-coated and QCh-coated displayed about two-fold higher inhibitory activity against Graffi tumor cells than that of free GOS at the 72nd h of incubation. As evidenced by the performed fluorescence microscopy analyses and SEM observations, the anti-tumor activity of the fibrous implants was mainly due to induction of apoptosis. The experiments in which the implants containing both QCh and GOS were placed locally into the tumor site after the tumor extirpation showed an increase in the survival rate and a lower rate of recurrence in the operative field and of metastases in regional lymph nodes. In this case, 40% of hamsters were alive on the 45th day of implantation and they did not show any clinical sign of recurrence in the operative field and metastases in the regional lymph nodes.

  10. The kinetics of the swelling process and the release mechanisms of Coriandrum sativum L. essential oil from chitosan/alginate/inulin microcapsules.

    Science.gov (United States)

    Dima, Cristian; Pătraşcu, Livia; Cantaragiu, Alina; Alexe, Petru; Dima, Ştefan

    2016-03-15

    The encapsulation by spray drying method of coriander essential oil (CEO) in various materials (chitosan, alginate, chitosan/alginate, chitosan/inulin) was studied. The viscoelastic properties of the oil-in-water (O/W) emulsions and the characteristics of CEO-loaded microcapsules like morphology, moisture, wettability, solubility, flowability properties, swelling and release mechanisms were investigated. The chitosan microcapsules had a brain-like structure while the alginate and chitosan/alginate microcapsules are spherical with a smooth surface. The Compressibility Index (CI=29.09-32.25%) and Hausner Ratio (HR=1.38-1.44) values showed that all the microcapsules prepared correspond to the "poor" flowability powders group. The chitosan microcapsules exhibited the maximum release rate at pH 2.5 while the alginate microcapsules exhibited the maximum release rate at pH 6.5. Kinetics and mechanism of CEO release were studied using various mathematical models such as, zero order, first order, Higuchi model and Peppas model. The diffusional exponent (n) values of Peppas equation explains a non Fickian transport mechanism and diffusion or diffusion-swelling controlled process.

  11. Chitosan coatings onto polyethylene terephthalate for the development of potential active packaging material

    Science.gov (United States)

    Zemljič, Lidija Fras; Tkavc, Tina; Vesel, Alenka; Šauperl, Olivera

    2013-01-01

    In this paper advanced surface treatment of PET plastic film is presented for introduction of antimicrobial properties as a potential application for food (as for example meat) packaging material. Adsorption/desorption of chitosan onto PET plastic film surface was studied using several analytical techniques such as: X-Ray Photoelectron Spectroscopy (XPS), ATR-FTIR spectroscopy and titrations. Kinetic desorption of chitosan from PET surface was analysed by polyelectrolyte titration and spectrophotometric Ninhydrine reaction. Standard antimicrobial test ASTM E2149-01 was performed for functionalised PET materials in order to determine their antimicrobial properties; i. e. to measure the reductions of some of the meat pathogens; such as bacteria Salmonella enterica, Campylobacter spp., Escherichia coli, Listeria monocytogenes and fungi Candida albicans.

  12. Cell line-dependent cytotoxicity of poly(isobutylcyanoacrylate) nanoparticles coated with chitosan and thiolated chitosan: Insights from cultured human epithelial HeLa, Caco2/TC7 and HT-29/MTX cells.

    Science.gov (United States)

    Pradines, Bénédicte; Lievin-Le Moal, Vanessa; Vauthier, Christine; Ponchel, Gilles; Loiseau, Philippe M; Bouchemal, Kawthar

    2015-08-01

    Nanoparticles composed of poly(isobutylcyanoacrylate) core coated with a mixture of chitosan and thiolated chitosan have already shown promising results in terms of mucoadhesion and permeation enhancement properties of pharmaceutical active drugs delivered via mucosal routes. In the present work, the cytotoxicity of these nanoparticles was first investigated using direct contact assay on undifferentiated human cervix epithelial HeLa cells. The results showed strong toxicity in HeLa cells for the two investigated concentrations 25 and 50 μg/mL. The cytotoxic effect was mainly attributed to the poly(isobutylcyanoacrylate) core since no significant differences in nanoparticle cytotoxicity were reported when nanoparticle shell composition was modified by adding chitosan or thiolated chitosan. In contrast, lower nanoparticle toxicity was reported using human fully-differentiated enterocyte-like Caco-2/TC7, and fully-differentiated mucus-secreting HT-29/MTX cells forming monolayer in culture mimicking an intestinal epithelial barrier. This study demonstrated that the toxicity of poly(isobutylcyanoacrylate) nanoparticles is highly cell line-dependent.

  13. Toxicity and antibacterial assessment of chitosan-coated silver nanoparticles on human pathogens and macrophage cells

    Directory of Open Access Journals (Sweden)

    Jena P

    2012-04-01

    Full Text Available Prajna Jena1, Soumitra Mohanty1, Rojee Mallick1, Biju Jacob2, Avinash Sonawane11School of Biotechnology, KIIT University, Bhubaneswar, Orissa, India; 2Center for Innovation, Technopark Technology Business Incubator, Bangalore, Karnataka, IndiaBackground: Pathogenic bacteria are able to develop various strategies to counteract the bactericidal action of antibiotics. Silver nanoparticles (AgNPs have emerged as a potential alternative to conventional antibiotics because of their potent antimicrobial properties. The purpose of this study was to synthesize chitosan-stabilized AgNPs (CS-AgNPs and test for their cytotoxic, genotoxic, macrophage cell uptake, antibacterial, and antibiofilm activities.Methods: AgNPs were synthesized using chitosan as both a stabilizing and a reducing agent. Antibacterial activity was determined by colony-forming unit assay and scanning electron microscopy. Genotoxic and cytotoxic activity were determined by DNA fragmentation, comet, and MTT [3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide] assays. Cellular uptake and intracellular antibacterial activity were tested on macrophages.Results: CS-AgNPs exhibited potent antibacterial activity against different human pathogens and also impeded bacterial biofilm formation. Scanning electron microscopy analysis indicated that CS-AgNPs kill bacteria by disrupting the cell membrane. CS-AgNPs showed no significant cytotoxic or DNA damage effect on macrophages at the bactericidal dose. Propidium iodide staining indicated active endocytosis of CS-AgNPs resulting in reduced intracellular bacterial survival in macrophages.Conclusion: The present study concludes that at a specific dose, chitosan-based AgNPs kill bacteria without harming the host cells, thus representing a potential template for the design of antibacterial agents to decrease bacterial colonization and to overcome the problem of drug resistance.Keywords: chitosan-silver nanoparticles, antibiofilm, cytotoxicity

  14. Phosphatidylcholine nanovesicles coated with chitosan or chondroitin sulfate as novel devices for bacteriocin delivery

    Science.gov (United States)

    da Silva, Indjara Mallmann; Boelter, Juliana Ferreira; da Silveira, Nádya Pesce; Brandelli, Adriano

    2014-07-01

    There is increased interest on the use of natural antimicrobial peptides in biomedicine and food preservation technologies. In this study, the antimicrobial activity of nisin encapsulated into nanovesicles containing polyanionic polysaccharides was investigated. Nisin was encapsulated in phosphatidylcholine (PC) liposomes containing chitosan or chondroitin sulfate by the thin-film hydration method and tested for antimicrobial activity against Listeria spp. The mean particle size of PC liposomes was 145 nm and varied to 210 and 134 nm with the incorporation of chitosan and chondroitin sulfate, respectively. Nisin-containing nanovesicles with and without incorporation of polysaccharides had a zeta potential values around -20 mV, showing mostly spherical structures when observed by transmission electron microscopy. Encapsulated nisin had similar efficiency as free nisin in inhibiting Listeria spp. isolated from bovine carcass, and greater efficiency in inhibiting Listeria monocytogenes. The formulation containing chitosan was more stable and more efficient in inhibiting L. monocytogenes when compared to the other nanovesicles tested. After 24 h, the viable cell counts were 2 log lower as compared with the other treatments and 7 log comparing to controls.

  15. Chitosan-Recombinamer Layer-by-Layer Coatings for Multifunctional Implants

    Science.gov (United States)

    Govindharajulu, Jeevan Prasaad; Chen, Xi; Li, Yuping; Rodriguez-Cabello, Jose Carlos; Battacharya, Mrinal; Aparicio, Conrado

    2017-01-01

    The main clinical problems for dental implants are (1) formation of biofilm around the implant—a condition known as peri-implantitis and (2) inadequate bone formation around the implant—lack of osseointegration. Therefore, developing an implant to overcome these problems is of significant interest to the dental community. Chitosan has been reported to have good biocompatibility and anti-bacterial activity. An osseo-inductive recombinant elastin-like biopolymer (P-HAP), that contains a peptide derived from the protein statherin, has been reported to induce biomineralization and osteoblast differentiation. In this study, chitosan/P-HAP bi-layers were built on a titanium surface using a layer-by-layer (LbL) assembly technique. The difference in the water contact angle between consecutive layers, the representative peaks in diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), X-ray photoelectron spectroscopy (XPS), and the changes in the topography between surfaces with a different number of bi-layers observed using atomic force microscopy (AFM), all indicated the successful establishment of chitosan/P-HAP LbL assembly on the titanium surface. The LbL-modified surfaces showed increased biomineralization, an appropriate mouse pre-osteoblastic cell response, and significant anti-bacterial activity against Streptococcus gordonii, a primary colonizer of tissues in the oral environment. PMID:28208793

  16. Maize seed coatings and seedling sprayings with chitosan and hydrogen peroxide:their influence on some phenological and biochemical behaviors

    Institute of Scientific and Technical Information of China (English)

    Eva-Guadalupe LIZ(A)RRAGA-PAUL(I)N; Susana-Patricia MIRANDA-CASTRO; Ernesto MORENO-MART(I)NEZ; Alma-Virginia LARA-SAGAH(O)N; Irineo TORRES-PACHECO

    2013-01-01

    Objective:To evaluate the effect of chitosan(CH)and hydrogen peroxide(H2O2)seed coatings and seedling sprinklings on two different maize varieties by measuring their phenology,the H2O2 presence,the catalase (CAT)activity,and the protein quantity.Methods:Seven groups of ten seeds for each maize variety were treated with CH(2%(20 g/L)and 0.2%(2 g/L))or H2O2(8 mmol/L)by coating,sprinkling,or both.Germination and seedling growth were measured.One month after germination,the presence of H2O2 in seedlings in the coated seed treatments was evaluated.Protein content and CAT activity were determined under all treatments.Results:H2O2 seed coating enhanced the germination rate and increased seedling and stem length in the quality protein maize(QPM)variety.Seedlings had a higher emergence velocity under this treatment in both varieties.CH and H2O2 sprinklings did not have an effect on seedling phenology.Exogenous application of H2O2 promoted an increase of endogenous H2O2.CH and H2O2 seedling sprinkling increased the protein content in both maize varieties,while there was no significant effect on the CAT activity of treated seeds and seedlings.Conclusions:CH and H2O2 enhance some phenological and biochemical features of maize depending on their method of application.

  17. 油炸涂膜薯片的吸油率和丙烯酰胺含量研究%Research on Oil Absorption Ratio and Acrylamide Content of Fried Potato Chips with Coatings

    Institute of Scientific and Technical Information of China (English)

    盛美香; 尤婷婷; 柳佳齐; 姜燕

    2015-01-01

    Carboxymethylcellulose Sodium (CMC) coating,soy protein isolate (SPI) coating and chitosan coating of different concentrations were coated on the surface of potato chips respectively.According to oil absorption rate and water content of fried potato chips,the appropriate coating solution were determined.The acrylamide content,color and sensory evaluation of fried potato chips coated with three coatings were compared in this situation simultaneously.Comparing with non-coating fried potato chips,the oil absorption ratio of fried chips coated with 1.5%CMC,8%SPI and 1.5%chitosan decreases 17.73%,22.94%and 7.58%and the acrylamide content decreases 21.5%,42.9%and 53.3%,respectively.Results indicate that SPI coating could reduce the oil absorption significantly,and chitosan coating could reduce the acrylamide content of fried potato chips.The product appears good sensory quality.%将不同浓度的羧甲基纤维素钠(CMC)膜液、大豆分离蛋白(SPI)膜液和壳聚糖膜液分别涂覆于薯片表面,高温油炸后,以薯片的吸油率和含水量为评价指标,确定3种膜液的最宜浓度,并对比了3种膜液最佳浓度下油炸薯片的丙烯酰胺含量、色泽值及感官品质.在CMC、SPI和壳聚糖膜液浓度分别为1.5%、8%和1.5%时,与未涂膜薯片对比,油炸涂膜薯片的吸油率分别下降17.73%、22.94%和7.58%,丙烯酰胺含量分别下降21.5%、42.9%和53.3%.结果表明,SPI涂膜可更大程度降低油炸薯片的吸油率,而壳聚糖涂膜可显著减少其丙烯酰胺含量,并具有较好的感官品质.

  18. Fortification of dark chocolate with spray dried black mulberry (Morus nigra) waste extract encapsulated in chitosan-coated liposomes and bioaccessability studies.

    Science.gov (United States)

    Gültekin-Özgüven, Mine; Karadağ, Ayşe; Duman, Şeyma; Özkal, Burak; Özçelik, Beraat

    2016-06-15

    Fine-disperse anionic liposomes containing black mulberry (Morus nigra) extract (BME) were prepared by high pressure homogenization at 25,000 psi. Primary liposomes were coated with cationic chitosan (0.4, w/v%) using the layer-by-layer depositing method and mixed with maltodextrin (MD) (20, w/v%) prior to spray drying. After that, spray dried liposomal powders containing BME were added to chocolates with alkalization degrees (pH 4.5, 6, 7.5) at conching temperatures of 40 °C, 60 °C, and 80 °C. The results showed that, compared to spray dried extract, chitosan coated liposomal powders provided better protection of anthocyanin content in both increased temperature and pH. In addition, encapsulation in liposomes enhanced in vitro bioaccessability of anthocyanins. Chocolate was fortified with encapsulated anthocyanins maximum 76.8% depending on conching temperature and pH.

  19. Application in the Ethanol Fermentation of Immobilized Yeast Cells in Matrix of Alginate/Magnetic Nanoparticles, on Chitosan-Magnetite Microparticles and Cellulose-coated Magnetic Nanoparticles

    CERN Document Server

    Ivanova, Viara; Hristov, Jordan

    2011-01-01

    Saccharomyces cerevisiae cells were entrapped in matrix of alginate and magnetic nanoparticles and covalently immobilized on magnetite-containing chitosan and cellulose-coated magnetic nanoparticles. Cellulose-coated magnetic nanoparticles with covalently immobilized thermostable {\\alpha}-amylase and chitosan particles with immobilized glucoamylase were also prepared. The immobilized cells and enzymes were applied in column reactors - 1/for simultaneous corn starch saccharification with the immobilized glucoamylase and production of ethanol with the entrapped or covalently immobilized yeast cells, 2/ for separate ethanol fermentation of the starch hydrolysates with the fixed yeasts. Hydrolysis of corn starch with the immobilized {\\alpha}-amylase and glucoamylase, and separate hydrolysis with the immobilized {\\alpha}-amylase were also examined. In the first reactor the ethanol yield reached approx. 91% of the theoretical; the yield was approx. 86% in the second. The ethanol fermentation was affected by the typ...

  20. Mineral-Coated Polymer Membranes with Superhydrophilicity and Underwater Superoleophobicity for Effective Oil/Water Separation

    OpenAIRE

    Peng-Cheng Chen; Zhi-Kang Xu

    2013-01-01

    Oil-polluted water is a worldwide problem due to the increasing industrial oily wastewater and the frequent oil spill accidents. Here, we report a novel kind of superhydrophilic hybrid membranes for effective oil/water separation. They were prepared by depositing CaCO3-based mineral coating on PAA-grafted polypropylene microfiltration membranes. The rigid mineral-coating traps abundant water in aqueous environment and forms a robust hydrated layer on the membrane pore surface, thus endowing t...

  1. Development of silver/titanium dioxide/chitosan adipate nanocomposite as an antibacterial coating for fruit storage

    Science.gov (United States)

    A novel nanocomposite of silver/titanium dioxide/chitosan adipate (Ag/TiO2/CS) was developed through photochemical reduction using a chitosan adipate template. Chitosan served as a reducing agent for the metal ions, and anchored metal ions by forming Ag–N coordination bonds and electrostatic attract...

  2. Supercritical CO2-Assisted Spray Drying of Strawberry-Like Gold-Coated Magnetite Nanocomposites in Chitosan Powders for Inhalation

    Directory of Open Access Journals (Sweden)

    Marta C. Silva

    2017-01-01

    Full Text Available Lung cancer is one of the leading causes of death worldwide. Therefore, it is of extreme importance to develop new systems that can deliver anticancer drugs into the site of action when initiating a treatment. Recently, the use of nanotechnology and particle engineering has enabled the development of new drug delivery platforms for pulmonary delivery. In this work, POXylated strawberry-like gold-coated magnetite nanocomposites and ibuprofen (IBP were encapsulated into a chitosan matrix using Supercritical Assisted Spray Drying (SASD. The dry powder formulations showed adequate morphology and aerodynamic performances (fine particle fraction 48%–55% and aerodynamic diameter of 2.6–2.8 µm for deep lung deposition through the pulmonary route. Moreover, the release kinetics of IBP was also investigated showing a faster release of the drug at pH 6.8, the pH of lung cancer. POXylated strawberry-like gold-coated magnetite nanocomposites proved to have suitable sizes for cellular internalization and their fluorescent capabilities enable their future use in in vitro cell based assays. As a proof-of-concept, the reported results show that these nano-in-micro formulations could be potential drug vehicles for pulmonary administration.

  3. Improved wettability and adhesion of polylactic acid/chitosan coating for bio-based multilayer film development

    Science.gov (United States)

    Gartner, Hunter; Li, Yana; Almenar, Eva

    2015-03-01

    The objective of this study was to investigate the effect of methyldiphenyl diisocyanate (MDI) concentration (0, 0.2, 1, 2, and 3%) on the wettability and adhesion of blend solutions of poly(lactic acid) (PLA) and chitosan (CS) when coated on PLA film for development of a bio-based multi-layer film suitable for food packaging and other applications. Characterization was carried out by attenuated total reflectance infrared spectrometry (ATR-FTIR), contact angle (θ), mechanical adhesion pull-off testing, and scanning electron microscopy (SEM). The θ of the PLA/CS blend shifted to a lower value (41-35°) with increasing MDI concentration showing that the surface tension was modified between the PLA/CS blend solution and PLA film and better wettability was achieved. The increase in MDI also resulted in an increased breaking strength (228-303 kPa) due to the increased H-bonding resulting from the more urethane groups formed within the PLA/CS blend as shown by ATR-FTIR. The improved adhesion was also shown by the increased number of physical entanglements observed by SEM. It can be concluded that MDI can be used to improve wettability and adhesion between PLA/CS coating and PLA film.

  4. Encapsulation of cardamom essential oil in chitosan nano-composites: In-vitro efficacy on antibiotic resistant bacterial pathogens and cytotoxicity studies.

    Directory of Open Access Journals (Sweden)

    Bushra Jamil

    2016-10-01

    Full Text Available Natural antimicrobial agents, particularly essential oils present an excellent alternative to current antibiotics due to their potent and broad-spectrum antimicrobial potential, unique mechanisms of action and low tendency to induce resistance. However their potential as a viable therapeutic alternative is greatly compromised due to their hydrophobic and volatile nature. The objective of the current research was to explore the anti-pathogenic potential of essential oils in a bio-based nano-carrier system. Six different essential oils were tested on multi-drug resistant bacterial pathogens. However, cardamom oil was selected for nano-encapsulation because of most potent anti-microbial activity. Cardamom oil loaded chitosan nano-particles were prepared by ionic gelation method with an encapsulation efficiency of more than 90% and size was estimated to be 50-100 nm. The Zeta potential was more than +50 mV that indicate a stable nano-dispersion. Cytotoxicity analysis indicated non haemolytic and non-cytotoxic behaviour on Human Corneal Epithelial Cells and HepG2 cell lines. Cardamom oil loaded chitosan nano-particles were found to exhibit excellent anti-microbial potential against extended spectrum β lactamase producing Escherichia coli and methicillin resistant Staphylococcus aureus. Our results suggested safety and efficacy of cardamom oil loaded chitosan nano-particles for treating multi drug resistant pathogens hence offer an effective alternative to current antibiotic therapy.

  5. Competitive Fixed-Bed Adsorption of Pb(II), Cu(II), and Ni(II) from Aqueous Solution Using Chitosan-Coated Bentonite

    OpenAIRE

    Wan-Chi Tsai; Mark Daniel G. de Luna; Bermillo-Arriesgado, Hanna Lee P.; Futalan, Cybelle M.; Colades, James I.; Meng-Wei Wan

    2016-01-01

    Fixed-bed adsorption studies using chitosan-coated bentonite (CCB) as adsorbent media were investigated for the simultaneous adsorption of Pb(II), Cu(II), and Ni(II) from a multimetal system. The effects of operational parameters such as bed height, flow rate, and initial concentration on the length of mass transfer zone, breakthrough time, exhaustion time, and adsorption capacity at breakthrough were evaluated. With increasing bed height and decreasing flow rate and initial concentration, th...

  6. Design, Development, and Optimization of Sterculia Gum-Based Tablet Coated with Chitosan/Eudragit RLPO Mixed Blend Polymers for Possible Colonic Drug Delivery

    OpenAIRE

    Bipul Nath; Lila Kanta Nath

    2013-01-01

    The purpose of this study is to explore the possible applicability of Sterculia urens gum as a novel carrier for colonic delivery system of a sparingly soluble drug, azathioprine. The study involves designing a microflora triggered colon-targeted drug delivery system (MCDDS) which consists of a central polysaccharide core and is coated to different film thicknesses with blends of chitosan/Eudragit RLPO, and is overcoated with Eudragit L00 to provide acid and intestinal resistance. The microfl...

  7. Control of Salmonella on fresh chicken breasts by κ-carrageenan/chitosan-based coatings containing allyl isothiocyanate or deodorized Oriental mustard extract plus EDTA.

    Science.gov (United States)

    Olaimat, Amin N; Holley, Richard A

    2015-06-01

    Control of Salmonella in poultry is a public health concern as salmonellosis is one of the most common foodborne diseases worldwide. This study aimed to screen the ability of 5 Salmonella serovars to degrade the mustard glucosinolate, sinigrin (by bacterial myrosinase) in Mueller-Hinton broth at 25 °C for 21 d and to reduce Salmonella on fresh chicken breasts by developing an edible 0.2% (w/v) κ-carrageenan/2% (w/v) chitosan-based coating containing Oriental mustard extract, allyl isothiocyanate (AITC), EDTA or their combinations. Individual Salmonella serovars degraded 50.2%-55.9% of the sinigrin present in 21 d. κ-Carrageenan/chitosan-based coatings containing 250 mg Oriental mustard extract/g or 50 μl AITC/g reduced the numbers of Salmonella on chicken breasts 2.3 log10 CFU/g at 21 d at 4 °C. However, when either mustard extract or AITC was combined with 15 mg/g EDTA in κ-carrageenan/chitosan-based coatings, Salmonella numbers were reduced 2.3 log10 CFU/g at 5 d and 3.0 log10 CFU/g at 21 d. Moreover, these treatments reduced numbers of lactic acid bacteria and aerobic bacteria by 2.5-3.3 log10 CFU/g at 21 d. κ-Carrageenan/chitosan coatings containing either 50 μl AITC/g or 250 mg Oriental mustard extract/g plus 15 mg EDTA/g have the potential to reduce Salmonella on raw chicken.

  8. Ionically Crosslinked Chitosan Hydrogels for the Controlled Release of Antimicrobial Essential Oils and Metal Ions for Wound Management Applications

    Directory of Open Access Journals (Sweden)

    Wan Li Low

    2016-03-01

    Full Text Available The emerging problems posed by antibiotic resistance complicate the treatment regime required for wound infections and are driving the need to develop more effective methods of wound management. There is growing interest in the use of alternative, broad spectrum, pre-antibiotic antimicrobial agents such as essential oils (e.g., tea tree oil, TTO and metal ions (e.g., silver, Ag+. Both TTO and Ag+ have broad spectrum antimicrobial activity and act on multiple target sites, hence reducing the likelihood of developing resistance. Combining such agents with responsive, controlled release delivery systems such as hydrogels may enhance microbiocidal activity and promote wound healing. The advantages of using chitosan to formulate the hydrogels include its biocompatible, mucoadhesive and controlled release properties. In this study, hydrogels loaded with TTO and Ag+ exhibited antimicrobial activity against P. aeruginosa, S. aureus and C. albicans. Combining TTO and Ag+ into the hydrogel further improved antimicrobial activity by lowering the effective concentrations required, respectively. This has obvious advantages for reducing the potential toxic effects on the healthy tissues surrounding the wound. These studies highlight the feasibility of delivering lower effective concentrations of antimicrobial agents such as TTO and Ag+ in ionically crosslinked chitosan hydrogels to treat common wound-infecting pathogens.

  9. Design, Development, and Optimization of Sterculia Gum-Based Tablet Coated with Chitosan/Eudragit RLPO Mixed Blend Polymers for Possible Colonic Drug Delivery.

    Science.gov (United States)

    Nath, Bipul; Nath, Lila Kanta

    2013-01-01

    The purpose of this study is to explore the possible applicability of Sterculia urens gum as a novel carrier for colonic delivery system of a sparingly soluble drug, azathioprine. The study involves designing a microflora triggered colon-targeted drug delivery system (MCDDS) which consists of a central polysaccharide core and is coated to different film thicknesses with blends of chitosan/Eudragit RLPO, and is overcoated with Eudragit L00 to provide acid and intestinal resistance. The microflora degradation property of gum was investigated in rat caecal medium. Drug release study in simulated colonic fluid revealed that swelling force of the gum could concurrently drive the drug out of the polysaccharide core due to the rupture of the chitosan/Eudargit coating in microflora-activated environment. Chitosan in the mixed film coat was found to be degraded by enzymatic action of the microflora in the colon. Release kinetic data revealed that the optimized MCDDS was fitted well into first-order model, and apparent lag time was found to be 6 hours, followed by Higuchi release kinetics. In vivo study in rabbits shows delayed T max, prolonged absorption time, decreased C max, and absorption rate constant (Ka), indicating a reduced systemic toxicity of the drug as compared to other dosage forms.

  10. Design, Development, and Optimization of Sterculia Gum-Based Tablet Coated with Chitosan/Eudragit RLPO Mixed Blend Polymers for Possible Colonic Drug Delivery

    Directory of Open Access Journals (Sweden)

    Bipul Nath

    2013-01-01

    Full Text Available The purpose of this study is to explore the possible applicability of Sterculia urens gum as a novel carrier for colonic delivery system of a sparingly soluble drug, azathioprine. The study involves designing a microflora triggered colon-targeted drug delivery system (MCDDS which consists of a central polysaccharide core and is coated to different film thicknesses with blends of chitosan/Eudragit RLPO, and is overcoated with Eudragit L00 to provide acid and intestinal resistance. The microflora degradation property of gum was investigated in rat caecal medium. Drug release study in simulated colonic fluid revealed that swelling force of the gum could concurrently drive the drug out of the polysaccharide core due to the rupture of the chitosan/Eudargit coating in microflora-activated environment. Chitosan in the mixed film coat was found to be degraded by enzymatic action of the microflora in the colon. Release kinetic data revealed that the optimized MCDDS was fitted well into first-order model, and apparent lag time was found to be 6 hours, followed by Higuchi release kinetics. In vivo study in rabbits shows delayed , prolonged absorption time, decreased , and absorption rate constant (Ka, indicating a reduced systemic toxicity of the drug as compared to other dosage forms.

  11. Improved wettability and adhesion of polylactic acid/chitosan coating for bio-based multilayer film development

    Energy Technology Data Exchange (ETDEWEB)

    Gartner, Hunter [School of Packaging, Michigan State University, East Lansing, Michigan (United States); Li, Yana [Mechanical Engineering College, Wuhan Polytechnic University (China); Almenar, Eva, E-mail: ealmenar@msu.edu [School of Packaging, Michigan State University, East Lansing, Michigan (United States)

    2015-03-30

    Graphical abstract: - Highlights: • Surface tension between PLA/CS blend solution and PLA film modified by MDI. • Better wettability between PLA/CS blend solution and PLA film by increasing MDI. • Increased breaking strength by increasing MDI due to the increased H-bonding. • Increased number of physical entanglements between PLA/CS coating and PLA film. • Development of a suitable bio-based multilayer film for food packaging applications. - Abstract: The objective of this study was to investigate the effect of methyldiphenyl diisocyanate (MDI) concentration (0, 0.2, 1, 2, and 3%) on the wettability and adhesion of blend solutions of poly(lactic acid) (PLA) and chitosan (CS) when coated on PLA film for development of a bio-based multi-layer film suitable for food packaging and other applications. Characterization was carried out by attenuated total reflectance infrared spectrometry (ATR-FTIR), contact angle (θ), mechanical adhesion pull-off testing, and scanning electron microscopy (SEM). The θ of the PLA/CS blend shifted to a lower value (41–35°) with increasing MDI concentration showing that the surface tension was modified between the PLA/CS blend solution and PLA film and better wettability was achieved. The increase in MDI also resulted in an increased breaking strength (228–303 kPa) due to the increased H-bonding resulting from the more urethane groups formed within the PLA/CS blend as shown by ATR-FTIR. The improved adhesion was also shown by the increased number of physical entanglements observed by SEM. It can be concluded that MDI can be used to improve wettability and adhesion between PLA/CS coating and PLA film.

  12. Adhesion and viability of two enterococcal strains on covalently grafted chitosan and chitosan/kappa-carrageenan multilayers

    NARCIS (Netherlands)

    Bratskaya, S.; Marinin, D.; Simon, F.; Synytska, A.; Zschoche, S.; Busscher, H. J.; Jager, D.; van der Mei, H. C.

    2007-01-01

    Chitosans are natural aminopolysaccharides, whose low cytotoxicity suggests their potential use for nonadhesive, antibacterial coatings on biomaterials implant surfaces. Here, the antiadhesive behavior and ability to kill bacteria upon adhesion ("contact killing") of chitosan coatings were evaluated

  13. Alginic acid-coated chitosan nanoparticles loaded with legumain DNA vaccine: effect against breast cancer in mice.

    Directory of Open Access Journals (Sweden)

    Ze Liu

    Full Text Available Legumain-based DNA vaccines have potential to protect against breast cancer. However, the lack of a safe and efficient oral delivery system restricts its clinical application. Here, we constructed alginic acid-coated chitosan nanoparticles (A.C.NPs as an oral delivery carrier for a legumain DNA vaccine. First, we tested its characteristic in acidic environments in vitro. DNA agarose electrophoresis data show that A.C.NPs protected DNA better from degradation in acidic solution (pH 1.5 than did chitosan nanoparticles (C.NPs. Furthermore, size distribution analysis showed that A.C.NPs tended to aggregate and form micrometer scale complexes in pH<2.7, while dispersing into nanoparticles with an increase in pH. Mice were intragastrically administrated A.C.NPs carrying EGFP plasmids and EGFP expression was detected in the intestinal Peyer's patches. Full-length legumain plasmids were loaded into different delivery carriers, including C.NPs, attenuated Salmonella typhimurium and A.C.NPs. A.C.NPs loaded with empty plasmids served as a control. Oral vaccination was performed in the murine orthotopic 4T1 breast cancer model. Our data indicate that tumor volume was significantly smaller in groups using A.C.NPs or attenuated Salmonella typhimurium as carriers. Furthermore, splenocytes co-cultured them with 4T1 cells pre-stimulated with CoCl2, which influenced the translocation of legumain from cytoplasm to plasma membrane, showed a 4.7 and 2.3 folds increase in active cytotoxic T lymphocytes (CD3(+/CD8(+/CD25(+ when treated with A.C.NPs carriers compared with PBS C.NPs. Our study suggests that C.NPs coated with alginic acid may be a safe and efficient tool for oral delivery of a DNA vaccine. Moreover, a legumain DNA vaccine delivered orally with A.C.NPs can effectively improve autoimmune response and protect against breast cancer in mice.

  14. Low molecular weight chitosan-coated silver nanoparticles are effective for the treatment of MRSA-infected wounds

    Science.gov (United States)

    Peng, Yinbo; Song, Chenlu; Yang, Chuanfeng; Guo, Qige; Yao, Min

    2017-01-01

    Silver nanoparticles (AgNPs) are being widely applied as topical wound materials; however, accumulated deposition of silver in the liver, spleen, and other main organs may lead to organ damage and dysfunction. We report here that low molecular weight chitosan-coated silver nanoparticles (LMWC-AgNPs) are effective against methicillin-resistant Staphylococcus aureus (MRSA), have better biocompatibility, and have lower body absorption characteristics when compared with polyvinylpyrrolidone-coated silver nanoparticles (PVP-AgNPs) and silver nanoparticles without surface stabilizer (uncoated-AgNPs) in a dorsal MRSA wound infection mouse model. LMWC-AgNPs were synthesized by reducing silver nitrate with low molecular weight chitosan as a stabilizer and reducing agent, while PVP-AgNPs were synthesized using polyvinylpyrrolidone as a stabilizer and ethanol as a reducing agent. AgNPs with different surface stabilizers were identified by UV-visible absorption spectrometry, and particle size was determined by transmission electron microscopy. UV-visible absorption spectra of LMWC-AgNPs, PVP-AgNPs and uncoated-AgNPs were similar and their sizes were in the range of 10–30 nm. In vitro experiments showed that the three types of AgNPs had similar MRSA-killing effects, with obvious effect at 4 μg/mL and 100% effect at 8 μg/mL. Bacteriostatic annulus experiments also showed that all the three types of AgNPs had similar antibacterial inhibitory effect at 10 μg/mL. Cell counting kit-8 assay and Hoechst/propidium iodide (PI) staining showed that LMWC-AgNPs were significantly less toxic to human fibroblasts than PVP-AgNPs and uncoated-AgNPs. Treatment of mice with MRSA wound infection demonstrated that the three types of AgNPs effectively controlled MRSA wound infection and promoted wound healing. After continuous application for 14 days, LMWC-AgNPs-treated mice showed significantly reduced liver dysfunction as demonstrated by the reduced alanine aminotransferase and aspartate

  15. Biological Evaluation (In Vitro and In Vivo) of Bilayered Collagenous Coated (Nano Electrospun and Solid Wall) Chitosan Membrane for Periodontal Guided Bone Regeneration.

    Science.gov (United States)

    Lotfi, Ghogha; Shokrgozar, Mohammad Ali; Mofid, Rasoul; Abbas, Fatemeh Mashhadi; Ghanavati, Farzin; Baghban, Alireza Akbarzadeh; Yavari, Seyedeh Kimia; Pajoumshariati, Seyedramin

    2016-07-01

    The application of barrier membranes in guided bone regeneration (GBR) has become a commonly used surgical technique in periodontal research. The objectives of this study were to evaluate the in vitro biocompatibility and osteogenic differentiation of mesenchymal stem cells (MSCs) on two different collagenous coatings (nano electrospun fibrous vs. solid wall) of bilayered collagen/chitosan membrane and their histological evaluation on bone regeneration in rabbit calvarial defects. It was found that chitosan-nano electrospun collagen (CNC) membranes had higher proliferation/metabolic activity compared to the chitosan-collagen (CC) and pristine chitosan membranes. The qRT-PCR analysis demonstrated the CNC membranes induced significant expression of osteogenic genes (Osteocalcin, RUNX2 and Col-α1) in MSCs. Moreover, higher calcium content and alkaline phosphatase activity of MSCs were observed compared to the other groups. Histologic and histomorphometric evaluations were performed on the uncovered (negative control) as well as covered calvarial defects of ten adult white rabbits with different membranes (CNC, CC, BioGide (BG, positive control)) at 1 and 2 months after surgery. More bone formation was detected in the defects covered with CNC and BG membranes than those covered by CC and the negative control. No inflammation and residual biomaterial particles were observed on the membrane surface or in the surrounding tissues in the surgical areas. These results suggest that bilayer CNC membrane can have the potential for use as a GBR membrane material facilitating bone formation.

  16. Application of a chitosan-immobilized Talaromyces thermophilus lipase to a batch biodiesel production from waste frying oils.

    Science.gov (United States)

    Romdhane, Ines Belhaj-Ben; Romdhane, Zamen Ben; Bouzid, Maha; Gargouri, Ali; Belghith, Hafedh

    2013-12-01

    Waste frying oil, which not only harms people's health but also causes environmental pollution, can be a good alternative to partially substitute petroleum diesel through transesterification reaction. This oil contained 8.8 % of free fatty acids, which cause a problem in a base-catalyzed process. In this study, synthesis of biodiesel was efficiently catalyzed by the covalently immobilized Talaromyces thermophilus lipase and allowed bioconversion yield up to 92 % after 24 h of reaction time. The optimal molar ratio was four to six parts of methanol to one part of oil with a biocatalyst loaded of 25 wt.% of oil. Further, experiments revealed that T. thermophilus lipase, immobilized by a multipoint covalent liaison onto activated chitosan via a short spacer (glutaraldehyde), was sufficiently tolerant to methanol. In fact, using the stepwise addition of methanol, no significant difference was observed from the one-step whole addition at the start of reaction. The batch biodiesel synthesis was performed in a fixed bed reactor with a lipase loaded of 10 g. The bioconversion yield of 98 % was attained after a 5-h reaction time. The bioreactor was operated successfully for almost 150 h without any changes in the initial conversion yield. Most of the chemical and physical properties of the produced biodiesel meet the European and USA standard specifications of biodiesel fuels.

  17. Adsorption of emulsified oil from metalworking fluid on activated bleaching earth-chitosan-SDS composites: Optimization, kinetics, isotherms.

    Science.gov (United States)

    Naowanat, Nitiya; Thouchprasitchai, Nutthavich; Pongstabodee, Sangobtip

    2016-03-15

    The adsorption of emulsified oil from metalworking fluid (MWF) on activated bleaching earth (BE)-chitosan-sodium dodecyl sulfate (SDS) composites (BE/MCS) was investigated under a statistical design of experiments at a 95% confidence interval to identify the critical factors and to optimize the adsorption capacity. The BE/MCS adsorbents were characterized by means of X-ray diffraction, Fourier transform infrared spectroscopy, Brunauer-Emmett-Teller adsorption/desorption isotherms, contact angle analysis (sessile drop technique) and their zeta potential. From the results of a full 2(5) factorial design with three center points, the adsorbent weight and initial pH of the MWF had a significant antagonistic effect on the adsorption capacity while the initial MWF concentration and BE:chitosan:SDS weight ratio had a synergistic influence. Temperature factor has no discernible effect on the capacity. From the FCCC-RSM design, the optimal capacity range of 2840-2922.5 mg g(-1) was achieved at sorbent weight of 1.6-1.9 g, pH of 5.5-6.5, initial MWF concentration of 52-55 g l(-1) and BE:chitosan:SDS (w/w/w) ratio of 4.7:1:1-6.2:1:1. To test the validation and sensitivity of RSM model, the results showed that the estimated adsorption capacity was close to the experimental capacity within an error range of ±3%, suggesting that the RSM model was acceptable and satisfied. From three kinetics models (pseudo-first-order, pseudo-second-order model and Avrami's equation) and two adsorption isotherms (Langmuir model and Freundlich model), assessed using an error function (Err) and the coefficient of determination (R(2)), Avrami's equation and Freundlich isotherm model provided a good fitting for the data, suggesting the presence of more than one reaction pathway in the MWF adsorption process and the heterogeneous surface adsorption of the BC/ABE-5.5 composite.

  18. Encapsulation in alginate and alginate coated-chitosan improved the survival of newly probiotic in oxgall and gastric juice.

    Science.gov (United States)

    Trabelsi, Imen; Bejar, Wacim; Ayadi, Dorra; Chouayekh, Hichem; Kammoun, Radhouane; Bejar, Samir; Ben Salah, Riadh

    2013-10-01

    This study was undertaken to develop an optimum composition model for the microencapsulation of a newly probiotic on sodium alginate using response surface methodology. The individual and interactive effects of three independent variables, namely sodium alginate concentration, biomass concentration, and hardening time, were investigated using Box-Behnken design experiments. A second ordered polynomial model was fitted and optimum conditions were estimated. The optimal conditions identified were 2% for sodium alginate, 10(10)UFC/ml for biomass, and 30 min for hardening time. The experimental value obtained for immobilized cells under these conditions was about 80.98%, which was in close agreement with the predicted value of 82.6%. Viability of microspheres (96%) was enhanced with chitosan as coating materials. The survival rates of free and microencapsulated Lactobacillus plantarum TN8 during exposure to artificial gastrointestinal conditions were compared. The results revealed that the encapsulated cells exhibited significantly higher resistances to artificial intestinal juice (AIJ) and artificial gastric juice (AGJ). Microencapsulation was also noted to effectively protect the strain from heating at 65 °C and refrigerating at 4 °C. Taken together, the findings indicated that microencapsulation conferred important protective effects to L. plantarum against the gastrointestinal conditions encountered during the transit of food.

  19. Effect of PEG and water-soluble chitosan coating on moxifloxacin-loaded PLGA long-circulating nanoparticles.

    Science.gov (United States)

    Mustafa, Sanaul; Devi, V Kusum; Pai, Roopa S

    2017-02-01

    Moxifloxacin (MOX) is a Mycobacterium tuberculosis DNA gyrase inhibitor. Due to its intense hydrophilicity, MOX is cleared from the body within 24 h and required for repetitive doses which may then result in hepatotoxicity and acquisition of MOX resistant-TB, related with its use. To overcome the aforementioned limitations, the current study aimed to develop PLGA nanoparticles (PLGA NPs), to act as an efficient carrier for controlled delivery of MOX. To achieve a substantial extension in blood circulation, a combined design, affixation of polyethylene glycol (PEG) to MOX-PLGA NPs and adsorption of water-soluble chitosan (WSC) (cationic deacetylated chitin) to particle surface, was rose for surface modification of NPs. Surface modified NPs (MOX-PEG-WSC NPs) were prepared to provide controlled delivery and circulate in the bloodstream for an extended period of time, thus minimizing dosing frequency. In vivo pharmacokinetic and in vivo biodistribution following oral administration were investigated. NP surface charge was closed to neutral +4.76 mV and significantly affected by the WSC coating. MOX-PEG-WSC NPs presented striking prolongation in blood circulation, reduced protein binding, and long-drawn-out the blood circulation half-life with resultant reduced liver sequestration vis-à-vis MOX-PLGA NPs. The studies, therefore, indicate the successful formulation development of MOX-PEG-WSC NPs that showed sustained release behavior from nanoparticles which indicates low frequency of dosing.

  20. Chitosan coated alginate-xanthan gum bead enhanced pH and thermotolerance of Lactobacillus plantarum LAB12.

    Science.gov (United States)

    Fareez, Ismail M; Lim, Siong Meng; Mishra, Rakesh K; Ramasamy, Kalavathy

    2015-01-01

    The vulnerability of probiotics at low pH and high temperature has limited their optimal use as nutraceuticals. This study addressed these issues by adopting a physicochemical driven approach of incorporating Lactobacillus plantarum LAB12 into chitosan (Ch) coated alginate-xanthan gum (Alg-XG) beads. Characterisation of Alg-XG-Ch, which elicited little effect on bead size and polydispersity, demonstrated good miscibility with improved bead surface smoothness and L. plantarum LAB12 entrapment when compared to Alg, Alg-Ch and Alg-XG. Sequential incubation of Alg-XG-Ch in simulated gastric juice and intestinal fluid yielded high survival rate of L. plantarum LAB12 (95%) at pH 1.8 which in turn facilitated sufficient release of probiotics (>7 log CFU/g) at pH 6.8 in both time- and pH-dependent manner. Whilst minimising viability loss at 75 and 90 °C, Alg-XG-Ch improved storage durability of L. plantarum LAB12 at 4 °C. The present results implied the possible use of L. plantarum LAB12 incorporated in Alg-XG-Ch as new functional food ingredient with health claims.

  1. Comparative study of chitosan- and PEG-coated lipid and PLGA nanoparticles as oral delivery systems for cannabinoids

    Energy Technology Data Exchange (ETDEWEB)

    Durán-Lobato, Matilde; Martín-Banderas, Lucía, E-mail: luciamartin@us.es [Universidad de Sevilla, Departmento Farmacia y Tecnología Farmacéutica, Facultad de Farmacia (España) (Spain); Gonçalves, Lídia M. D. [Universidade de Lisboa, Research Institute for Medicines and Pharmaceutical Sciences (iMed.UL), Faculdade de Farmácia (Portugal); Fernández-Arévalo, Mercedes [Universidad de Sevilla, Departmento Farmacia y Tecnología Farmacéutica, Facultad de Farmacia (España) (Spain); Almeida, Antonio J. [Universidade de Lisboa, Research Institute for Medicines and Pharmaceutical Sciences (iMed.UL), Faculdade de Farmácia (Portugal)

    2015-02-15

    The cannabinoid derivative 1-naphthalenyl[4-(pentyloxy)-1-naphthalenyl]methanone (CB13) has an important therapeutic potential as analgesic in chronic pain states that respond poorly to conventional drugs. However, the incidence of its mild-to-moderate and dose-dependent adverse effects, as well as its pharmacokinetic profile, actually holds back its use in humans. Thus, the use of a suitable carrier system for oral delivery of CB13 becomes an attractive strategy to develop a valuable therapy. Polymeric poly(lactic-co-glycolic) acid (PLGA) and lipid nanoparticles (LNPs) are widely studied delivery vehicles that improve the bioavailability of lipophilic compounds and present special interest in oral delivery. Their surface can be modified to improve the adhesion of particles to the oral mucosa and increase their circulation time in blood with additives such as chitosan (CS) and polyethylene glycol (PEG), which can be feasibly incorporated onto these particles in a post-production step. In this work, CS- and PEG-modified polymeric PLGA and LNPs were successfully obtained and comparatively evaluated under the same experimental conditions as oral carriers for CB13. All the formulations presented adequate blood compatibility and absence of cytotoxicity in Caco-2 cells. Coating with CS led to a higher interaction with Caco-2 cells and a limited uptake in THP1 cells, while coating with PEG led to a limited uptake in Caco-2 cells and strongly prevented THP1 cells uptake. The performance of each formulation is discussed as a comparison of the potential of these carriers as oral delivery systems of CB13.

  2. High-Performance Capacitive Deionization Disinfection of Water with Graphene Oxide-graft-Quaternized Chitosan Nanohybrid Electrode Coating.

    Science.gov (United States)

    Wang, Yilei; El-Deen, Ahmed G; Li, Peng; Oh, Bernice H L; Guo, Zanru; Khin, Mya Mya; Vikhe, Yogesh S; Wang, Jing; Hu, Rebecca G; Boom, Remko M; Kline, Kimberly A; Becker, David L; Duan, Hongwei; Chan-Park, Mary B

    2015-10-27

    Water disinfection materials should ideally be broad-spectrum-active, nonleachable, and noncontaminating to the liquid needing sterilization. Herein, we demonstrate a high-performance capacitive deionization disinfection (CDID) electrode made by coating an activated carbon (AC) electrode with cationic nanohybrids of graphene oxide-graft-quaternized chitosan (GO-QC). Our GO-QC/AC CDID electrode can achieve at least 99.9999% killing (i.e., 6 log reduction) of Escherichia coli in water flowing continuously through the CDID cell. Without the GO-QC coating, the AC electrode alone cannot kill the bacteria and adsorbs a much smaller fraction (<82.8 ± 1.8%) of E. coli from the same biocontaminated water. Our CDID process consists of alternating cycles of water disinfection followed by electrode regeneration, each a few minutes duration, so that this water disinfection process can be continuous and it only needs a small electrode voltage (2 V). With a typical brackish water biocontamination (with 10(4) CFU mL(-1) bacteria), the GO-QC/AC electrodes can kill 99.99% of the E. coli in water for 5 h. The disinfecting GO-QC is securely attached on the AC electrode surface, so that it is noncontaminating to water, unlike many other chemicals used today. The GO-QC nanohybrids have excellent intrinsic antimicrobial properties in suspension form. Further, the GO component contributes toward the needed surface conductivity of the CDID electrode. This CDID process offers an economical method toward ultrafast, contaminant-free, and continuous killing of bacteria in biocontaminated water. The proposed strategy introduces a green in situ disinfectant approach for water purification.

  3. Mineral-coated polymer membranes with superhydrophilicity and underwater superoleophobicity for effective oil/water separation.

    Science.gov (United States)

    Chen, Peng-Cheng; Xu, Zhi-Kang

    2013-09-27

    Oil-polluted water is a worldwide problem due to the increasing industrial oily wastewater and the frequent oil spill accidents. Here, we report a novel kind of superhydrophilic hybrid membranes for effective oil/water separation. They were prepared by depositing CaCO3-based mineral coating on PAA-grafted polypropylene microfiltration membranes. The rigid mineral-coating traps abundant water in aqueous environment and forms a robust hydrated layer on the membrane pore surface, thus endowing the membranes with underwater superoleophobicity. Under the drive of either gravity or external pressure, the hybrid membranes separate a range of oil/water mixtures effectively with high water flux (>2000 L m(-2) h(-1)), perfect oil/water separation efficiency (>99%), high oil breakthrough pressure (>140 kPa) and low oil fouling. The oil/water mixtures include not only free mixtures but also oil-in-water emulsions. Therefore, the mineral-coated membrane enables an efficient and energy-saving separation for various oil/water mixtures, showing attractive potential for practical oil/water separation.

  4. Preparation and Evaluation of Enteric-Coated Chitosan Derivative-Based Microparticles Loaded with Salmon Calcitonin as an Oral Delivery System

    Directory of Open Access Journals (Sweden)

    Hiraku Onishi

    2016-09-01

    Full Text Available Background: The production of protein drugs has recently increased due to advances in biotechnology, but their clinical use is generally limited to parenteral administration due to low absorption in non-parenteral administration. Therefore, non-parenteral delivery systems allowing sufficient absorption draw much attention. Methods: Microparticles (MP were prepared using chitosan-4-thio-butylamidine conjugate (Ch-TBA, trimethyl-chitosan (TMC, and chitosan (Ch. Using salmon calcitonin (sCT as a model protein drug, Ch-TBA-, Ch-TBA/TMC (4/1-, and Ch-based MP were produced, and their Eudragit L100 (Eud-coated MP, named Ch-TBA-MP/Eud, Ch-TBA/TMC-MP/Eud, and Ch-MP/Eud, respectively, were prepared as oral delivery systems. These enteric-coated microparticles were examined in vitro and in vivo. Results: All microparticles before and after enteric coating had a submicron size (600–800 nm and micrometer size (1300–1500 nm, respectively. In vitro release patterns were similar among all microparticles; release occurred gradually, and the release rate was slower at pH 1.2 than at pH 6.8. In oral ingestion, Ch-TBA-MP/Eud suppressed plasma Ca levels most effectively among the microparticles tested. The relative effectiveness of Ch-TBA-MP/Eud to the intramuscular injection was 8.6%, while the sCT solution showed no effectiveness. Conclusion: The results suggest that Eud-coated Ch-TBA-based microparticles should have potential as an oral delivery system of protein drugs.

  5. A study of chitosan hydrogel with embedded mesoporous silica nanoparticles loaded by ibuprofen as a dual stimuli-responsive drug release system for surface coating of titanium implants.

    Science.gov (United States)

    Zhao, Pengkun; Liu, Hongyu; Deng, Hongbing; Xiao, Ling; Qin, Caiqin; Du, Yumin; Shi, Xiaowen

    2014-11-01

    In this study, the complex pH and electro responsive system made of chitosan hydrogel with embedded mesoporous silica nanoparticles (MSNs) was evaluated as a tunable drug release system. As a model drug, ibuprofen (IB) was used; its adsorption in MSNs was evidenced by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and thermogravimetric analysis (TG). In order to prepare the complex drug release system, the loaded particles IB-MSNs were dispersed in chitosan solution and then the complex IB-MSNs/chitosan film of 2mm thickness was deposited as a hydrogel on the titanium electrode. The codeposition of components was performed under a negative biasing of the titanium electrode at -0.75 mA/cm2 current density during 30 min. The IB release from the IB-MSNs/chitosan hydrogel film was studied as dependent on pH of the release media and electrical conditions applied to the titanium plate. When incubating the complex hydrogel film in buffers with different pH, the IB release followed a near zero-order profile, though its kinetics varied. Compared to the spontaneous IB release from the hydrogel in 0.9% NaCl solution (at 0 V), the application of negative biases to the coated titanium plate had profound effluences on the release behavior. The release was retarded when -1.0 V was applied, but a faster kinetics was observed at -5.0 V. These results imply that a rapid, mild and facile electrical process for covering titanium implants by complex IB-MSNs/chitosan hydrogel films can be used for controlled drug delivery applications.

  6. The Research of Chitosan Coated Membrane Fresh Strawberries%壳聚糖涂膜保鲜草莓的研究

    Institute of Scientific and Technical Information of China (English)

    何士敏; 陈易; 晁利花

    2014-01-01

    本试验用七八成熟的草莓为材料,对草莓果实采用不同浓度的壳聚糖处理涂膜,并分别在4℃和常温(12℃~15℃)下贮藏,测定贮藏期间经壳聚糖处理以后草莓的失重率,可溶性固形物的含量、VC含量、总糖含量、总酸含量和呼吸强度的变化,研究壳聚糖涂膜对草莓果实保鲜的影响。试验结果表明,在草莓的贮藏中,壳聚糖涂膜处理对草莓有一定的保鲜作用,以浓度1.25%壳聚糖溶液处理保鲜效果最佳。尤其是在4℃条件下,浓度1.25%壳聚糖溶液处理明显降低了草莓果实的腐烂程度与失重率,延缓了果实贮藏后期可溶性固形物、有机酸含量、总糖含量以及VC的降低,减少了呼吸损耗,提高了草莓果实贮藏期间品质。%The experiment with seven or eight ripe strawberry on strawberry fruit as material , the different concentration of chitosan treatment, and at 4℃and at room temperature to 12℃-15℃under storage, measured during the storage of strawberry treated by chitosan after the weight loss rate, soluble solids content, vitamin C content, total sugar content, total acid content and the changes of respiration intensity, study of chitosan coating on preservation of strawberry fruits effect. The test results showed that, in the strawberry storage, chitosan coating on strawberry has certain effect, with a concentration of 1.25 % chitosan solution preservation effect best. Especially under the condition of 4 DEG C, the concentration of 1.25%chitosan solution treatment significantly reduces the strawberry fruit decay degree and rate of weight loss, delay fruit storage period of soluble solids, organic acid content, total sugar content and vitamin C reduce, decrease of breathing loss, improves the quality of strawberry fruit during storage.

  7. Complex coacervation of collagen hydrolysate extracted from leather solid wastes and chitosan for controlled release of lavender oil.

    Science.gov (United States)

    Ocak, Buğra

    2012-06-15

    In the world, approximately 600,000 metric tonnes of chromium-containing solid wastes are generated by the leather industry each year. Environmental concerns and escalating landfill costs are becoming increasingly serious problems to the leather industry and seeking solutions to these problems is a prime concern in much research today. In this study, solid collagen-based protein hydrolysate was isolated from chromium-tanned leather wastes and its chemical properties were determined. Microcapsules of collagen hydrolysate (CH) - chitosan (C) crosslinked with glutaraldehyde (GA) containing Lavender oil (LO) were prepared by complex coacervation method. The effects of various processing parameters, including the CH to C ratio, LO content, and GA, on the oil load (%), oil content (%), encapsulation efficiency (%) and release rate of LO from microcapsules were investigated. As the ratio of C present in the CH/C mixture and crosslinking density increased, the release rate of LO from microcapsules slowed down. Optical and scanning electron microscopy images illustrated that the LO microcapsules were spherical in shape. Fourier transform infrared spectroscopy (FTIR) studies confirmed that there was no significant interaction between CH/C complex and LO.

  8. Electrophoretic Deposition of Chitosan Coatings Modified with Gelatin Nanospheres To Tune the Release of Antibiotics

    NARCIS (Netherlands)

    Song, J.; Chen, Q.; Zhang, Y.; Diba, M.; Kolwijck, E.; Shao, J.; Jansen, J.A.; Yang, F.; Boccaccini, A.R.; Leeuwenburgh, S.C.

    2016-01-01

    Orthopedic and dental implants are increasingly used in the medical field in view of their high success rates. Implant-associated infections, however, still occur and are difficult to treat. To combat these infections, the application of an active coating to the implant surface is advocated as an ef

  9. In vitro and in vivo degradation and mechanical properties of ZEK100 magnesium alloy coated with alginate, chitosan and mechano-growth factor.

    Science.gov (United States)

    Gao, Hong; Zhang, Meng; Zhao, Jin; Gao, Lilan; Li, Mingshuo

    2016-06-01

    The biocompatibility, ultimate loading capacity and biodegradability of magnesium alloy make it an ideal candidate in biomedical fields. Fabrications of multilayered coatings carrying sodium alginate (ALG), chitosan (CHI) and mechano-growth factor (MGF) on fluoride-pretreated ZEK100 magnesium alloy have been obtained via layer by layer (LBL) to reduce the degradation rate of magnesium alloy in this study. The modified surfaces of ZEK100 substrates were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier transform infrared (FTIR) and CARE EUT-1020 tester. Results reveal that multilayer-coated magnesium alloy can be successfully obtained with smooth surface morphology, and the mechanical properties of coated samples are almost the same as those of uncoated samples. However, the fatigue life of coated ZEK100 is slightly larger than that of uncoated samples after 1 day of immersion. By comparing the degradation of uncoated and multilayer-coated ZEK100 samples in vitro and in vivo, respectively, it is found that the degradation rate of ZEK100 samples can be inhibited by LBL modification on the surface of the sample; and the corrosion rate in vivo is lower than that in vitro, which help solve the rapid degradation problem of magnesium alloy. In terms of the visible symptom of tissues in the left femur medullary cavity and material responses on the surface, multilayer-coated ZEK100 magnesium alloy has a good biocompatibility. These results indicate that multilayer-coated ZEK100 may be a promising material for bone tissue repair.

  10. Application of fungal chitosan incorporated with pomegranate peel extract as edible coating for microbiological, chemical and sensorial quality enhancement of Nile tilapia fillets.

    Science.gov (United States)

    Alsaggaf, Mohammed S; Moussa, Shaaban H; Tayel, Ahmed A

    2017-06-01

    Fish are generous sources for providing man with his essential nutritional requirements, but the extreme susceptibility to quality deterioration hinders their optimal usage and storage. Natural derivatives are always the perfect alternatives for food preservation. The application of fungal chitosan (Ch), from Aspergillus niger, and pomegranate peel extract (PPE), in coating films for Nile tilapia (Oreochromis niloticus) fillets preservation ‎and maintaining their microbiological, chemical and sensorial quality during cooled storage at 4°C for 30days, was investigated.‎ Fish fillet were coated with Ch (2%) and combined Ch+PPE, at PPE percentages of 0.5, 1.0, 1.5 and 2.0%. Fillets coating resulted in sharp decrease of the entire microbial counts during storage; the increased concentrations from PPE strengthened coating film antimicrobial activity. Additionally, fillets coating could retard the chemical spoilage parameters increasing, i.e. nitrogen volatile base (TVB-N), peroxide value (PV) and reactive substances of thiobarbituric acid (TBARS), during storage period. The sensory evaluation indicated higher preferences for the odor, texture, color and overall quality of coated samples. Fish fillets coating with Ch and Ch+PPE could be recommended for shelf life extension and maintaining the microbiological, chemical and sensorial quality through the application of safe preservatives from natural origins.

  11. Remediation of fluoride from drinking water using magnetic iron oxide coated hydrotalcite/chitosan composite.

    Science.gov (United States)

    Pandi, Kalimuthu; Periyasamy, Soodamani; Viswanathan, Natrayasamy

    2017-02-16

    The present study was performed to examine the probability of magnetic iron oxide fabricated hydrotalcite/chitosan (Fe3O4@HTCS) composite for the removal of excess fluoride content from drinking water. The developed Fe3O4@HTCS composite not only demonstrate the good separation ability but also display an extreme enhanced defluoridation capacity (DC) when compared to other base components and composite. The DCs of Fe3O4@HTCS composite, Fe3O4@HT composite, Fe3O4, HT and CS was found to be 5032, 3041, 1050, 1030 and 52mgF(-)/kg respectively. The structure and morphology of the prepared adsorbent and fluoride sorbed adsorbent was analysed using FTIR, SEM and EDAX with mapping techniques. The dependence of DC on various parameters like initial fluoride concentration, pH, contact time, interfering anions and temperature was studied by batch method. From isotherm modeling, the equilibrium data is well described by Freundlich, Langmuir and Dubinin-Radushkevich (D-R) isotherms. Thermodynamic parameters confirm the spontaneity and endothermic nature of the fluoride adsorption. The performance of Fe3O4@HTCS composite to field water sample designates its adaptable nature at field conditions.

  12. Magnetic removal of Entamoeba cysts from water using chitosan oligosaccharide-coated iron oxide nanoparticles.

    Science.gov (United States)

    Shukla, Sudeep; Arora, Vikas; Jadaun, Alka; Kumar, Jitender; Singh, Nishant; Jain, Vinod Kumar

    2015-01-01

    Amebiasis, a major health problem in developing countries, is the second most common cause of death due to parasitic infection. Amebiasis is usually transmitted by the ingestion of Entamoeba histolytica cysts through oral-fecal route. Herein, we report on the use of chitosan oligosaccharide-functionalized iron oxide nanoparticles for efficient capture and removal of pathogenic protozoan cysts under the influence of an external magnetic field. These nanoparticles were synthesized through a chemical synthesis process. The synthesized particles were characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and zeta potential analysis. The particles were found to be well dispersed and uniform in size. The capture and removal of pathogenic cysts were demonstrated by fluorescent microscopy, transmission electron microscopy, and scanning electron microscopy (SEM). Three-dimensional modeling of various biochemical components of cyst walls, and thereafter, flexible docking studies demonstrate the probable interaction mechanism of nanoparticles with various components of E. histolytica cyst walls. Results of the present study suggest that E. histolytica cysts can be efficiently captured and removed from contaminated aqueous systems through the application of synthesized nanoparticles.

  13. Effective photosensitization-based inactivation of Gram (-) food pathogens and molds using the chlorophyllin-chitosan complex: towards photoactive edible coatings to preserve strawberries.

    Science.gov (United States)

    Buchovec, Irina; Lukseviciute, Viktorija; Marsalka, Arunas; Reklaitis, Ignas; Luksiene, Zivile

    2016-04-01

    This study is focused on the novel approaches to enhance the inactivation of the Gram (-) food pathogen Salmonella enterica and harmful molds in vitro and on the surface of strawberries using the chlorophyllin-chitosan complex. Salmonella enterica (∼1 × 10(7) CFU mL(-1)) was incubated with chlorophyllin 1.5 × 10(-5) M (Chl, food additive), chitosan 0.1% (CHS, food supplement) or the chlorophyllin-chitosan complex (1.5 × 10(-5) M Chl-0.1% CHS) and illuminated with visible light (λ = 405 nm, light dose 38 J cm(-2)) in vitro. Chlorophyllin (Chl)-based photosensitization inactivated Salmonella just by 1.8 log. Chitosan (CHS) alone incubated for 2 h with Salmonella reduced viability 2.15 log, whereas photoactivated Chl-CHS diminished bacterial viability by 7 log. SEM images indicate that the Chl-CHS complex under these experimental conditions covered the entire bacterial surface. Significant cell membrane disintegration was the main lethal injury induced in Gram (-) bacteria by this treatment. Analysis of strawberry decontamination from surface-inoculated Salmonella indicated that photoactivated Chl-CHS (1.5 × 10(-5) M Chl-0.1% CHS, 30 min incubation, light dose 38 J cm(-2)) coatings diminished the pathogen population on the surface of strawberries by 2.2 log. Decontamination of strawberries from naturally distributed yeasts/molds revealed that chitosan alone reduced the population of yeasts/molds just by 0.4 log, Chl-based photosensitization just by 0.9 log, whereas photoactivated Chl-CHS coatings reduced yeasts/molds on the surface of strawberries by 1.4 log. Electron paramagnetic resonance spectroscopy confirmed that no additional photosensitization-induced free radicals have been found in the strawberry matrix. Visual quality (color, texture) of the treated strawberries was not affected either. In conclusion, photoactive Chl-CHS exhibited strong antimicrobial action against more resistant to photosensitization Gram (-) Salmonella enterica in comparison with

  14. Pharmacokinetics of menthol and carvone after administration of an enteric coated formulation containing peppermint oil and caraway oil.

    Science.gov (United States)

    Mascher, H; Kikuta, C; Schiel, H

    2001-01-01

    Enteric coating of peppermint oil/caraway oil capsules avoids subjective discomfort to the patient caused by gastroesophageal reflux. In order to confirm bioequivalence of an enteric coated formulation containing peppermint oil and caraway oil (CAS 277309-55-4, Enteroplant) and an immediate release formulation of both oils, the pharmacokinetics of menthol and carvone after oral administration of the two formulations were studied in a randomized, two-period cross-over study in 16 healthy male volunteers. The subjects received 180 mg peppermint oil and 100 mg caraway oil, once as 2 enteric coated capsules of the fixed enteric coated combination preparation containing 90 mg peppermint oil (WS 1340) and 50 mg caraway oil (WS 1520) each (test) and once in the form of 5 capsules of an immediate release formulation (reference) containing 36 mg peppermint (WS 1340) oil and 20 mg caraway oil (WS 1520) each. The capsules were taken with 250 ml water after a 10 h fast. Both substances were determined in plasma by GC/MS after extraction. The limit of quantification was 10 ng/ml for menthol and 0.5 ng/ml for carvone. The mean maximum plasma levels for menthol were 1196 ng/ml after administration of the test medication and 1492 ng/ml after administration of the reference medication. The bioavailability with respect to the AUC was comparable after administration of test and reference preparation, the 90% confidence interval was 97 to 105%. As expected, there were considerable differences for Tmax. After application of the enteric coated form the maximum concentration was reached significantly later (3.0 h vs. 1.7 h) compared to the immediate release capsule. Corresponding data were also calculated for carvone. After application of the test medication the maxima of 14 ng/ml for both formulations were reached later (2.5 h vs. 1.3 h). The 90% confidence interval of the AUC for carvone was 79 to 119% and therefore slightly outside the acceptable range for bioequivalence of 80 to 125

  15. Natural Minerals Coated by Biopolymer Chitosan: Synthesis, Physicochemical, and Adsorption Properties

    OpenAIRE

    Budnyak, T. M.; Yanovska, E. S.; Kichkiruk, O. Yu.; Sternik, D.; Tertykh, V. A.

    2016-01-01

    Natural minerals are widely used in treatment technologies as mineral fertilizer, food additive in animal husbandry, and cosmetics because they combine valuable ion-exchanging and adsorption properties together with unique physicochemical and medical properties. Saponite (saponite clay) of the Ukrainian Podillya refers to the class of bentonites, a subclass of layered magnesium silicate montmorillonite. Clinoptilolits are aluminosilicates with carcase structure. In our work, we have coated bi...

  16. Self-healing epoxy coating containing linseed oil loaded micro capsules for steel

    Directory of Open Access Journals (Sweden)

    M. Mahmoudian

    2016-12-01

    Full Text Available Effectiveness of epoxy coatings filled with linseed oil loaded micro capsules was investigated for healing the cracks generated on steel. Micro capsules were synthesized by in-situ polymerization method. Characteristics of these micro capsules were studied by Fourier-transform infrared spectroscopy (FTIR, Thermal gravimetric analysis, Scanning electron microscopy (SEM for chemical investigation, thermal stability and surface morphology respectively. Anti-corrosion effect of prepared coating was investigated by electrochemical impedance spectroscopy (EIS. Cracks in a paint film were successfully healed when linseed oil was released from microcapsules ruptured under simulated mechanical action.Linseed oil healed area was found to prevent corrosion of the substrate.

  17. Chitosan-whey protein isolate composite films for encapsulation and stabilization of fish oil containing ultra pure omega-3 fatty acids.

    Science.gov (United States)

    Duan, Jingyun; Jiang, Yan; Zhao, Yanyun

    2011-01-01

    Chitosan (1.5%, w/v)-whey protein isolate (WPI, 5% w/v) composite films were developed for encapsulating and stabilizing fish oil (FO) containing 93.7% eicosapentaenoic acid (EPA). Chitosan-WPI film-forming solutions (FFS) were incorporated with 1.5% or 2% FO (w/v), 2% (w/v) glycerol, Tween 80 (3 times weight of FO), and 0.5% (w/v) oregano or rosemary essential oil (EO), and cast for films at room conditions. Dried films were stored at 2 °C for 30 d for evaluating encapsulation efficiency (EE), lipid stability, and film functionality. Total oil contents in films from FFS incorporating 1.5% or 2% FO were 28.1% to 32.5% and 33.4% to 37.3%, respectively, and free oil contents were 13.5% to 14.7% and 15.5% to 16.3%, respectively. EE, moisture content, and water activity of the films were 47.8% to 66%, 18.7% to 24.9%, and 0.42% to 0.50%, respectively, without significant difference among differently formulated films. Increasing FO concentration from 1.5% to 2% in FFS decreased tensile strength of the films from 0.57-0.73 to 0.34-0.44 MPa, but not the film elongation. Addition of oregano EO in FFS retarded lipid oxidation of the fish oil encapsulated in the films, in which a 43% to 53% reduction in thiobarbituric acid-reactive substances value and 39% to 51% reduction in peroxide value were achieved. Chitosan-WPI composite films with incorporation of oregano essential oil could be applied as a simple and economic means for encapsulating and stabilizing fish oil for fortifying omega-3 fatty acids in various applications.

  18. Effect of packaging with Chitosan biodegradable films formulated with Garlic essential oil (Allium sativum L. on the chemical properties of chicken fillet

    Directory of Open Access Journals (Sweden)

    E Molaee Aghaee

    2016-01-01

    Full Text Available Background and Objective: Considering the environmental problems raised from current plastic packaging, edible and biodegradable films could be developed and also be effective in controlling the chemical and microbial properties of food especially if their effect be strengthened by adding natural antioxidant and antimicrobial agents like herbal essential oils. This study aimed at assessing the effect of packaging with chitosan film containing garlic essential oil on the chemical changes of chicken fillet during storage at refrigeration temperature. Materials and Methods: Different levels of garlic essential oil (0, 0.5, 1 and 2% were used in chitosan film preparation. Through casting method and using glycerol as plasticizer and tween 80 as emulsifier, different films were prepared after homogenization and molding. Chemical tests were conducted in days 0, 2, 4, 7, 10, and 14 on chicken fillets covered with different films and stored at 4 °C. Statistical analysis was performed using SPSS software. Results: Samples covered with different films showed lower values for pH, total volatile nitrogen (TVN, Thiobarbituric acid-reactive substances (TBARs, and peroxide index (P.V compared with controls during the study (p &le 0.05. Generally, a dose-dependent trend was observed by essential oil addition. Conclusion: Chicken packaging with chitosan film especially by adding various levels of garlic essential oil could had a preventive effect on major chemical spoilage factors. Considering the relatively similar preventive effect of 1 and 2 % essential oil levels and also economic aspects, optimum dose for essential oil could be 1 % in the film.

  19. In-vitro bioactivity, biocorrosion and antibacterial activity of silicon integrated hydroxyapatite/chitosan composite coating on 316 L stainless steel implants

    Energy Technology Data Exchange (ETDEWEB)

    Sutha, S.; Kavitha, K.; Karunakaran, G.; Rajendran, V., E-mail: veerajendran@gmail.com

    2013-10-15

    A simple and effective ultrasonication method was applied for the preparation of 0, 0.4, 0.8, 1.0 and 1.6 wt% silicon substituted hydroxyapatite (HAp) (SH). The Ca/P ratio of the synthesised SH nanoparticles were in the range of 1.58–1.70. Morphological changes were noticed in HAp with respect to the amount of Si from 0 to 1.6 wt%. The morphology of the particles changed from spherical shape to rod-like morphology with respect to the amount of Si which was confirmed using transmission electron microscopy. X-ray diffraction studies confirm the formation of phase pure SH nanoparticles without any secondary phase. Chitosan (CTS) blended SH nanocomposites coating on surgical grade 316 L stainless steel (316 L SS) implant was made by spin coating technique. The surface of the coated implant was characterised using scanning electron microscopy which confirms the uniform coating without cracks and pores. The increased corrosion resistance of the 1.6 wt% of SH/CTS-coated SS implant in the simulated body fluid (SBF) indicates the long-term biostability of SH composite-coated ceramics in vitro than the 0 wt% SH/CTS. The testing of SH/CTS nanocomposites with gram-positive and gram-negative bacterial strains confirms that the antibacterial ability improves with the higher substitution of Si. In addition, formation of bone-like apatite layer on the SH/CTS-coated implant in SBF was studied through SEM analysis and it confirms the ability to increase the HAp formation on the surface of 1.0 wt% SH/CTS-coated 316 L SS implant. Highlights: • Hydroxyapatite particles are prepared with various silicon concentration • Prepared composites are blended with chitosan and coated on the implant • Corrosion resistance in simulated body fluid improves its stability • Increase in silicon concentration improves the antibacterial activity • Coated plate exhibit high in-vitro bioactivity in simulated body fluid.

  20. Chitosan coated Ag/ZnO nanocomposite and their antibiofilm, antifungal and cytotoxic effects on murine macrophages.

    Science.gov (United States)

    Thaya, Rajagopalan; Malaikozhundan, Balasubramanian; Vijayakumar, Sekar; Sivakamavalli, Jeyachandran; Jeyasekar, Raja; Shanthi, Sathappan; Vaseeharan, Baskaralingam; Ramasamy, Palaniappan; Sonawane, Avinash

    2016-11-01

    In the present study, chitosan coated Ag/ZnO (CS/Ag/ZnO) nanocomposite was synthesized and characterized by UV-Vis spectroscopy (UV-Vis), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM). The CS/Ag/ZnO nanocomposite exhibited antibacterial activity against Gram positive (B. licheniformis and B. cereus) bacteria at 8 μg mL(-1) compared to Gram negative (V. parahaemolyticus. and P. vulgaris) bacteria. CS/Ag/ZnO nanocomposite effectively inhibited the biofilm growth of Gram positive bacteria compared to Gram negative bacteria at 30 μg mL(-1). The hydrophobicity index and EPS (extracellular polysaccharide) production of both Gram positive and Gram negative bacteria was decreased after treatment with 30 μg mL(-1) of CS/Ag/ZnO nanocomposite. CS/Ag/ZnO nanocomposite showed effective control of fungal C. albicans biofilm (92%) at 50 μg mL(-1). The inhibition of bacterial and fungal biofilms was clearly visualized under light and confocal laser scanning microscopy (CLSM). CS/Ag/ZnO nanocomposite was observed to be non toxic to RAW264.7 murine macrophages and no changes in the morphology of macrophages was observed under phase contrast microscopy. The study concludes that CS/Ag/ZnO nanocomposite is the promising candidate to be used as biomaterial against bacterial and fungal infections without any toxicity risk.

  1. Magnetic resonance imaging of mouse islet grafts labeled with novel chitosan-coated superparamagnetic iron oxide nanoparticles.

    Directory of Open Access Journals (Sweden)

    Jyuhn-Huarng Juang

    Full Text Available OBJECT: To better understand the fate of islet isografts and allografts, we utilized a magnetic resonance (MR imaging technique to monitor mouse islets labeled with a novel MR contrast agent, chitosan-coated superparamagnetic iron oxide (CSPIO nanoparticles. MATERIALS AND METHODS: After being incubated with and without CSPIO (10 µg/ml, C57BL/6 mouse islets were examined under transmission electron microscope (TEM and their insulin secretion was measured. Cytotoxicity was examined in α (αTC1 and β (NIT-1 and βTC cell lines as well as islets. C57BL/6 mice were used as donors and inbred C57BL/6 and Balb/c mice were used as recipients of islet transplantation. Three hundred islets were transplanted under the left kidney capsule of each mouse and then MR was performed in the recipients periodically. At the end of study, the islet graft was removed for histology and TEM studies. RESULTS: After incubation of mouse islets with CSPIO (10 µg/mL, TEM showed CSPIO in endocytotic vesicles of α- and β-cells at 8 h. Incubation with CSPIO did not affect insulin secretion from islets and death rates of αTC1, NIT-1 and βTC cell lines as well as islets. After syngeneic and allogeneic transplantation, grafts of CSPIO-labeled islets were visualized on MR scans as persistent hypointense areas. At 8 weeks after syngeneic transplantation and 31 days after allogeneic transplantation, histology of CSPIO-labeled islet grafts showed colocalized insulin and iron staining in the same areas but the size of allografts decreased with time. TEM with elementary iron mapping demonstrated CSPIO distributed in the cytoplasm of islet cells, which maintained intact ultrastructure. CONCLUSION: Our results indicate that after syngeneic and allogeneic transplantation, islets labeled with CSPIO nanoparticles can be effectively and safely imaged by MR.

  2. Chitosan-Coated Magnetic Nanoparticles Prepared in One-Step by Precipitation in a High-Aqueous Phase Content Reverse Microemulsion

    Directory of Open Access Journals (Sweden)

    María Guadalupe Pineda

    2014-07-01

    Full Text Available Chitosan-coated magnetic nanoparticles (CMNP were prepared in one-step by precipitation in a high-aqueous phase content reverse microemulsion in the presence of chitosan. The high-aqueous phase concentration led to productivities close to 0.49 g CMNP/100 g microemulsion; much higher than those characteristic of precipitation in reverse microemulsions for preparing magnetic nanoparticles. The obtained nanoparticles present a narrow particle size distribution with an average diameter of 4.5 nm; appearing to be formed of a single crystallite; furthermore they present superparamagnetism and high magnetization values; close to 49 emu/g. Characterization of CMNP suggests that chitosan is present as a non-homogeneous very thin layer; which explains the slight reduction in the magnetization value of CMNP in comparison with that of uncoated magnetic nanoparticles. The prepared nanoparticles show high heavy ion removal capability; as demonstrated by their use in the treatment of Pb2+ aqueous solutions; from which lead ions were completely removed within 10 min.

  3. Study of Oil-bearing Wastewater Treatment by Chitosan-bentonite and PDMDAAC-bentonite%壳聚糖和PDMDAAC改性膨润土用于处理含油废水的研究

    Institute of Scientific and Technical Information of China (English)

    邵红; 刘相龙; 王大卫; 徐微雪

    2014-01-01

    modified bentonite to adsorb oil in oil-bearing wastewater were investigated and compared. Experimental results show that removing rates were improved to 87. 8% and 89. 3% by using chitosan-bentonite and PDMDAAC-bentonite,respectively. The processing time is shorter than 15 min. Compared with the traditional method,the new method is less time-consuming and has a higher efficiency. With Fourier Transform Infrared Spectroscopy( FT-IR),X-ray Diffraction( XRD)and Scanning Electron Microscope( SEM),the results show that chitosan and PDMDAAC is coated as Na+-bentonite. Comparisons of adsorption performance show that PDMDAAC-bentonite is an improvement on chitosan-bentonite. PDMDAAC-bentonite has high efficiency,low cost and is easy to operate,and can be used in wastewater treatment extensively.

  4. Primary Study on Impact of Chitosan Coating to Seedling Rate of Chinese Cabbage%壳聚糖包衣对大白菜种子出苗率的影响研究初报

    Institute of Scientific and Technical Information of China (English)

    程季珍; 武峻新; 程伯瑛

    2012-01-01

    Three-year experiment of Chinese cabbage seeds with three specifications of chitosan coating showed: seed with chitosan coating in those years had normal growth, phytotoxicity and increased seedling rate. But considering the relationship of chitosan dosage with seedling rate, seedling rate of the coated seed in 1 ~ 2 storage years, no using of industrial chitosan coating was suggested. When coated seed with aluminum foil bag was kept in storage over 1 year, it was better not to be kept with 0.149 mm chitosan of food level; while available 3.4 ~ 13.6 mg/20 g seed of 0.177 mm chitosan of food level could improve stress and storage resistance of seed.%2003-2005年通过用3种规格的壳聚糖分别包衣大白菜种子进行试验,结果表明,当年包衣种子的幼苗生长正常,无药害,出苗率提高.但结合壳聚糖用量与出苗率之间的关系及包衣种子贮存1~2 a后的出苗率,不宜用工业级壳聚糖包衣大白菜种子;若用铝箔袋贮存包衣种子1a以上,也不宜用0.149 mm食品级壳聚糖,20g种子用3.4~13.6mg的0.177 mm食品级壳聚糖包衣较适用,能提高种子的抗逆性和耐贮性.

  5. In situ preparation of high relaxivity iron oxide nanoparticles by coating with chitosan: A potential MRI contrast agent useful for cell tracking

    Science.gov (United States)

    Tsai, Zei-Tsan; Wang, Jen-Fei; Kuo, Hsiao-Yun; Shen, Chia-Rui; Wang, Jiun-Jie; Yen, Tzu-Chen

    2010-01-01

    Iron oxide nanocrystals are of considerable interest in nanoscience and nanotechnology because of their nanoscale dimensions, nontoxic nature, and superior magnetic properties. Colloidal solutions of magnetic nanoparticles (ferrofluids) with a high magnetite content are highly desirable for most molecular imaging applications. In this paper, we present a method for in situ coating of superparamagnetic iron oxide (SPIO) with chitosan in order to increase the content of magnetite. Iron chloride salts (Fe 3+ and Fe 2+) were directly coprecipitated inside a porous matrix of chitosan by Co-60 γ-ray irradiation in an aqueous solution of acetic acid. Following sonication, iron oxide nanoparticles were formed inside the chitosan matrix at a pH value of 9.5 and a temperature of 50 °C. The [Fe 3+]:[Fe 2+]:[NH 4OH] molar ratio was 1.6:1:15.8. The final ferrofluid was formed with a pH adjustment to approximately 2.0/3.0, alongside with the addition of mannitol and lactic acid. We subsequently characterized the particle size, the zeta potential, the iron concentration, the magnetic contrast, and the cellular uptake of our ferrofluid. Results showed a z-average diameter of 87.2 nm, a polydispersity index (PDI) of 0.251, a zeta potential of 47.9 mV, and an iron concentration of 10.4 mg Fe/mL. The MRI parameters included an R1 value of 22.0 mM -1 s -1, an R2 value of 202.6 mM -1 s -1, and a R2/R1 ratio of 9.2. An uptake of the ferrofluid by mouse macrophages was observed. Altogether, our data show that Co-60 γ-ray radiation on solid chitosan may improve chitosan coating of iron oxide nanoparticles and tackle its aqueous solubility at pH 7. Additionally, our methodology allowed to obtain a ferrofluid with a higher content of magnetite and a fairly unimodal distribution of monodisperse clusters. Finally, MRI and cell experiments demonstrated the potential usefulness of this product as a potential MRI contrast agent that might be used for cell tracking.

  6. In vitro and in vivo degradation and mechanical properties of ZEK100 magnesium alloy coated with alginate, chitosan and mechano-growth factor

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Hong; Zhang, Meng; Zhao, Jin [School of Chemical Engineering and Technology, Tianjin University, Tianjin (China); Gao, Lilan, E-mail: gaolilan780921@163.com [School of Chemical Engineering and Technology, Tianjin University, Tianjin (China); Tianjin Key Laboratory for Control Theory & Applications in Complicated Industry Systems, School of Mechanical Engineering, Tianjin University of Technology, Tianjin (China); Li, Mingshuo [School of Chemical Engineering and Technology, Tianjin University, Tianjin (China)

    2016-06-01

    The biocompatibility, ultimate loading capacity and biodegradability of magnesium alloy make it an ideal candidate in biomedical fields. Fabrications of multilayered coatings carrying sodium alginate (ALG), chitosan (CHI) and mechano-growth factor (MGF) on fluoride-pretreated ZEK100 magnesium alloy have been obtained via layer by layer (LBL) to reduce the degradation rate of magnesium alloy in this study. The modified surfaces of ZEK100 substrates were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier transform infrared (FTIR) and CARE EUT-1020 tester. Results reveal that multilayer-coated magnesium alloy can be successfully obtained with smooth surface morphology, and the mechanical properties of coated samples are almost the same as those of uncoated samples. However, the fatigue life of coated ZEK100 is slightly larger than that of uncoated samples after 1 day of immersion. By comparing the degradation of uncoated and multilayer-coated ZEK100 samples in vitro and in vivo, respectively, it is found that the degradation rate of ZEK100 samples can be inhibited by LBL modification on the surface of the sample; and the corrosion rate in vivo is lower than that in vitro, which help solve the rapid degradation problem of magnesium alloy. In terms of the visible symptom of tissues in the left femur medullary cavity and material responses on the surface, multilayer-coated ZEK100 magnesium alloy has a good biocompatibility. These results indicate that multilayer-coated ZEK100 may be a promising material for bone tissue repair. - Highlights: • The fabrications of multilayered coatings were successfully obtained via layer by layer. • Surface modification has little effect on the mechanical properties of magnesium alloy. • Surface modification can reduce the corrosion rate of magnesium alloy. • Corrosion rate in vivo is lower than that in vitro. • Multilayer-coated ZEK100 magnesium alloy has a good biocompatibility.

  7. Effect of antioxidant and optimal antimicrobial mixtures of carvacrol, grape seed extract and chitosan on different spoilage microorganisms and their application as coatings on different food matrices

    Directory of Open Access Journals (Sweden)

    Javiera F. Rubilar

    2013-04-01

    Full Text Available There is growing interest in the use of natural agents with antimicrobial (AM and antioxidant (AOX properties. Optimization of the AM capacity for mixtures containing carvacrol, grape seed extract (GSE and chitosan, against gram-negative (Pseudomonas aeruginosa, gram-positive bacteria (Staphylococcus aureus, Listeria innocua and Enterococcus faecalis and yeast (Saccharomyces cerevisiae at 106 cfu mL-1 was studied. To observe the synergistic or antagonistic effect and find optimal combinations between the three agents, a simplex centroid mixture design was run for each microorganism, combining carvacrol (0-300 ppm, X1, GSE (0-2000 ppm, X2 and chitosan (0-2% w/v, X3. Results of the response surface analysis showed several synergistic effects for all microorganisms. Combinations of 60 ppm-400 ppm-1.2% w/v (carvacrol-GSE-chitosan; optimal AM combination 1, OAMC-1; 9.6 ppm-684 ppm-1.25% w/v (OAMC-2; 90 ppm-160 ppm-1.24% w/v (OAMC-3 were found to be the optimal mixtures for all microorganisms. Radical scavenging activity (RSA of the same agents was then compared with a standard AOX (butylated hydroxytoluene; BHT at different concentrations (25, 50 and 100 ppm; as well as the optimal AM concentrations by the 1,1-diphenyl-2-picrylhydrazyl (DPPH method. RSA increased in the following order: chitosan< carvacrol< BHT< GSE and for the OAMC: OAMC-2< OAMC-1< OAMC-3. The best RSA (OAMC-3 was applied as a coating in two different food matrices (strawberries and salmon. For strawberries, P. aeruginosa was more sensitive to the action of OAMC-3 than S. cerevisiae. For salmon, S. aureus was more resistant to the action of OAMC-3 than E. faecalis and L. innocua.

  8. In-vitro bioactivity, biocorrosion and antibacterial activity of silicon integrated hydroxyapatite/chitosan composite coating on 316 L stainless steel implants.

    Science.gov (United States)

    Sutha, S; Kavitha, K; Karunakaran, G; Rajendran, V

    2013-10-01

    A simple and effective ultrasonication method was applied for the preparation of 0, 0.4, 0.8, 1.0 and 1.6 wt% silicon substituted hydroxyapatite (HAp) (SH). The Ca/P ratio of the synthesised SH nanoparticles were in the range of 1.58-1.70. Morphological changes were noticed in HAp with respect to the amount of Si from 0 to 1.6 wt%. The morphology of the particles changed from spherical shape to rod-like morphology with respect to the amount of Si which was confirmed using transmission electron microscopy. X-ray diffraction studies confirm the formation of phase pure SH nanoparticles without any secondary phase. Chitosan (CTS) blended SH nanocomposites coating on surgical grade 316 L stainless steel (316 L SS) implant was made by spin coating technique. The surface of the coated implant was characterised using scanning electron microscopy which confirms the uniform coating without cracks and pores. The increased corrosion resistance of the 1.6 wt% of SH/CTS-coated SS implant in the simulated body fluid (SBF) indicates the long-term biostability of SH composite-coated ceramics in vitro than the 0 wt% SH/CTS. The testing of SH/CTS nanocomposites with gram-positive and gram-negative bacterial strains confirms that the antibacterial ability improves with the higher substitution of Si. In addition, formation of bone-like apatite layer on the SH/CTS-coated implant in SBF was studied through SEM analysis and it confirms the ability to increase the HAp formation on the surface of 1.0 wt% SH/CTS-coated 316 L SS implant.

  9. 壳聚糖涂膜对西葫芦保鲜效果的研究%Effect of Chitosan Coating on Preservation of Summer Squash

    Institute of Scientific and Technical Information of China (English)

    袁蒙蒙; 高丽朴; 王清; 高元惠; 杨娜

    2013-01-01

      研究不同浓度的壳聚糖涂膜对西葫芦采后生理生化指标的影响.试验结果表明:采用壳聚糖涂膜处理均可以有效维持西葫芦外观品质,抑制采后呼吸强度,并能延迟呼吸高峰的出现,延缓西葫芦果实中可溶性固形物和叶绿素的降解,抑制细胞膜透性的上升和丙二醛的积累,提高膜脂保护酶CAT的活性.其中以0.75%浓度的壳聚糖涂膜效果最佳.%The effects of different concentrations of chitosan coating films on main physical-chemical characteris changing of summer squash were studied. The results showed that summer squash with chitosan coating treatment can restrain the respiration rate, postpone the appearing time of respiration peak, delay the decline of SSC and chlorophyll. In addition, the raise of cell membrane permeability and MDA were inhabited, the CAT activity was reservedatahighlevel.Thebestconcentrationwas0.75%.

  10. Hemocompatibility of poly(ɛ-caprolactone) lipid-core nanocapsules stabilized with polysorbate 80-lecithin and uncoated or coated with chitosan.

    Science.gov (United States)

    Bender, Eduardo A; Adorne, Márcia D; Colomé, Letícia M; Abdalla, Dulcinéia S P; Guterres, Sílvia S; Pohlmann, Adriana R

    2012-04-15

    The hemocompatibility of nanoparticles is of critical importance for their systemic administration as drug delivery systems. Formulations of lipid-core nanocapsules, stabilized with polysorbate 80-lecithin and uncoated or coated with chitosan (LNC and LNC-CS), were prepared and characterized by laser diffraction (D[4,3]: 129 and 134 nm), dynamic light scattering (119 nm and 133 nm), nanoparticle tracking (D50: 124 and 139 nm) and particle mobility (zeta potential: -15.1 mV and +9.3 mV) analysis. In vitro hemocompatibility studies were carried out with mixtures of nanocapsule suspensions in human blood at 2% and 10% (v/v). The prothrombin time showed no significant change independently of the nanocapsule surface potential or its concentration in plasma. Regarding the activated partial thromboplastin time, both suspensions at 2% (v/v) in plasma did not influence the clotting time. Even though suspensions at 10% (v/v) in plasma decreased the clotting times (p<0.05), the values were within the normal range. The ability of plasma to activate the coagulation system was maintained after the addition of the formulations. Suspensions at 2% (v/v) in blood showed no significant hemolysis or platelet aggregation. In conclusion, the lipid-core nanocapsules uncoated or coated with chitosan are hemocompatible representing a potential innovative nanotechnological formulation for intravenous administration.

  11. Competitive adsorption of Cu (II), Co (II) and Ni (II) from their binary and tertiary aqueous solutions using chitosan-coated perlite beads as biosorbent.

    Science.gov (United States)

    Swayampakula, Kalyani; Boddu, Veera M; Nadavala, Siva Kumar; Abburi, Krishnaiah

    2009-10-30

    A new composite chitosan-coated biosorbent was prepared and was used for the removal and recovery of heavy metals from aqueous solution. In the present investigation, equilibrium adsorption characteristics of Cu (II), Ni (II), and Co (II) from their binary and tertiary solution on newly developed biosorbent chitosan-coated perlite beads were evaluated through batch and column studies. These beads were characterized by using FTIR, EDXRF and surface area analysis techniques. The effect of various biosorption parameters like effect of pH, agitation time, concentration of adsorbate and amount of adsorbent on extent of adsorption was investigated. The adsorption follows Lagergren first order kinetic model. The equilibrium adsorption data were fitted to Freundlich and Langmuir adsorption isotherm models and the model parameters were evaluated. Both the models represent the experimental data satisfactorily. The sorbent loaded with metal was regenerated with 0.1N NaOH solution. Furthermore the column dynamic studies indicate the re-usage of the biosorbent.

  12. Mussel-inspired hydrophobic coatings for water-repellent textiles and oil removal.

    Science.gov (United States)

    García, Beatríz; Saiz-Poseu, Javier; Gras-Charles, Roser; Hernando, Jordi; Alibés, Ramon; Novio, Fernando; Sedó, Josep; Busqué, Félix; Ruiz-Molina, Daniel

    2014-10-22

    A series of catechol derivatives with a different number of linear alkyl chain substituents, and different length, have been shown to polymerize in the presence of aqueous ammonia and air, yielding hydrophobic coatings that present the ability to provide robust and efficient water repellency on weaved textiles, including hydrophilic cotton. The polymerization strategy presented exemplifies an alternative route to established melanin- and polydopamine-like functional coatings, affording designs in which all catechol (adhesive) moieties support specific functional side chains for maximization of the desired (hydrophobic) functionality. The coatings obtained proved effective in the transformation of polyester and cotton weaves, as well as filter paper, into reusable water-repellent, oil-absorbent materials capable of retaining roughly double their weight in model compounds (n-tetradecane and olive oil), as well as of separating water/oil mixtures by simple filtration.

  13. Assessment of penetration potential of pH responsive double walled biodegradable nanogels coated with eucalyptus oil for the controlled delivery of 5-fluorouracil: In vitro and ex vivo studies.

    Science.gov (United States)

    Sahu, Prashant; Kashaw, Sushil K; Jain, Sanyog; Sau, Samaresh; Iyer, Arun K

    2017-03-17

    Penetration enhancers coated biodegradable polymeric nanogels loaded with cytotoxic drugs applied via the topical route, can be a promising strategy for improving the chemotherapeutic efficiency of skin cancers. The major objective of proposed research was to investigate the in vitro and ex vivo chemotherapeutic potential of double walled PLGA-chitosan biodegradable nanogel entrapped with 5-fluororuacil (5-FU) coated with eucalyptus oil, topically applied onto the skin. 5-FU was first entrapped in PLGA core by solvent evaporation technique followed by coating with cationic chitosan for ionic interaction with anionic skin cancer cell membrane. A surface coating of eucalyptus oil (1%) was employed to improve the penetration efficacy of the nanogel into stratum corneum. The surface modified biodegradable double walled nanogel was characterized for particle size, charge and thermal properties followed by pH dependent in vitro analysis. Human keratinocyte (HaCaT) cell line was employed for the bio- and cyto-compatibility testing prior to the hemolysis assay and coagulation assessment. A porcine skin ex vivo screening was performed for assessing the penetration potential of the nanogels. DLS and TEM revealed a particle size of 170nm for the double walled nanogels. The nanogels also exhibited high thermal stability as analyzed by thermogravimetry (TG) and differential thermal analysis (DTA). The drug entrapment efficacy was about ~45%. The drug release showed sustained release pattern noted up to 24h. The low hemolysis of 3.31% with short prothrombin time (PT) and activated partial thromboplastin time (APTT) of 13.5 and 33s respectively, revealed high biocompatibility of the nanogels. The cellular uptake and localization was assessed by confocal microscopy. The cytotoxicity (MTT assay) on HaCaT cell line demonstrated high cytocompatibilty of the nanogels. An ex vivo evaluation using porcine skin displayed efficient and steady state flux of 5-FU from the biodegradable

  14. Transcutaneous iontophoretic delivery of STAT3 siRNA using layer-by-layer chitosan coated gold nanoparticles to treat melanoma.

    Science.gov (United States)

    Labala, Suman; Jose, Anup; Venuganti, Venkata Vamsi Krishna

    2016-10-01

    Overexpression of signal transducer and activator of transcription 3 (STAT3) protein prevents apoptosis and enhances proliferation of melanocytes. The aim of this study was to investigate the feasibility of using layer-by-layer assembled gold nanoparticles (LbL-AuNP) as a carrier for iontophoretic delivery of STAT3 siRNA to treat melanoma. Chitosan coated AuNP (AuNP-CS) were prepared by direct reduction of HAuCl4 in the presence of chitosan. The AuNP-CS were then sequentially layered with siRNA and chitosan to form AuNP-CS/siRNA/CS. STAT3 siRNA replaced with scrambled siRNA or sodium alginate were used as controls. The average particle size and zeta-potential of the prepared LbL-AuNP were 150±10nm (PDI: 0.41±0.06) and 35±6mV, respectively. In vitro studies in B16F10 murine melanoma cells showed that AuNP-CS/siRNA/CS inhibited the cell growth by 49.0±0.6% and 66.0±0.2% at 0.25nM and 0.5nM STAT3 siRNA concentration, respectively. Fluorescence microscopy and flow cytometry studies showed a time dependent cell uptake of the LbL-AuNP up to 120min. Clathrin mediated endocytosis was found to be the predominant cell uptake mechanism for LbL-AuNP. STAT3 siRNA loaded LbL-AuNP reduced the STAT3 protein expression by 47.3% in B16F10 cells. Similarly, apoptosis assay showed 29% and 44% of early and late apoptotic events, respectively after treatment with STAT3 siRNA loaded LbL-AuNP. Confocal microscope and skin cryosections showed that application of 0.47mA/cm(2) of anodal iontophoresis enhanced the skin penetration of LbL-AuNP to reach viable epidermis. In conclusion, layer-by-layer chitosan coated AuNP can be developed as a carrier for iontophoretic delivery of STAT3 siRNA to treat melanoma.

  15. Chitosan-PLGA polymer blends as coatings for hydroxyapatite nanoparticles and their effect on antimicrobial properties, osteoconductivity and regeneration of osseous tissues.

    Science.gov (United States)

    Ignjatović, Nenad; Wu, Victoria; Ajduković, Zorica; Mihajilov-Krstev, Tatjana; Uskoković, Vuk; Uskoković, Dragan

    2016-03-01

    Composite biomaterials comprising nanostructured hydroxyapatite (HAp) have an enormous potential for natural bone tissue reparation, filling and augmentation. Chitosan (Ch) as a naturally derived polymer has many physicochemical and biological properties that make it an attractive material for use in bone tissue engineering. On the other hand, poly-D,L-lactide-co-glycolide (PLGA) is a synthetic polymer with a long history of use in sustained drug delivery and tissue engineering. However, while chitosan can disrupt the cell membrane integrity and may induce blood thrombosis, PLGA releases acidic byproducts that may cause tissue inflammation and interfere with the healing process. One of the strategies to improve the biocompatibility of Ch and PLGA is to combine them with compounds that exhibit complementary properties. In this study we present the synthesis and characterization, as well as in vitro and in vivo analyses of a nanoparticulate form of HAp coated with two different polymeric systems: (a) Ch and (b) a Ch-PLGA polymer blend. Solvent/non-solvent precipitation and freeze-drying were used for synthesis and processing, respectively, whereas thermogravimetry coupled with mass spectrometry was used for phase identification purposes in the coating process. HAp/Ch composite particles exhibited the highest antimicrobial activity against all four microbial strains tested in this work, but after the reconstruction of the bone defect they also caused inflammatory reactions in the newly formed tissue where the defect had lain. Coating HAp with a polymeric blend composed of Ch and PLGA led to a decrease in the reactivity and antimicrobial activity of the composite particles, but also to an increase in the quality of the newly formed bone tissue in the reconstructed defect area.

  16. Wound Healing Bionanocomposites Based on Castor Oil Polymeric Films Reinforced with Chitosan-Modified ZnO Nanoparticles.

    Science.gov (United States)

    Díez-Pascual, Ana M; Díez-Vicente, Angel L

    2015-09-14

    Castor oil (CO), which is a readily available, relatively inexpensive, and environmentally benign nonedible oil, has been successfully used as matrix material to prepare biocompatible and biodegradable nanocomposite films filled with chitosan (CS)-modified ZnO nanoparticles. The biocomposites were synthesized via a simple and versatile solution mixing and casting method. The morphology, structure, thermal stability, water absorption, biodegradability, cytocompatibility, barrier, mechanical, viscoelastic, antibacterial, and wound healing properties of the films have been analyzed. FT-IR spectra were used to obtain information about the nanoparticle-matrix interactions. The thermal stability, hydrophilicity, degree of porosity, water absorption, water vapor transmission rate (WVTR), oxygen permeability (Dk), and biodegradability of the films increased with the CS-ZnO loading. The WVTR and Dk data obtained are within the range of values reported for commercial wound dressings. Tensile tests demonstrated that the nanocomposites displayed a good balance between elasticity, strength, and flexibility under both dry and simulated body fluid (SBF) environments. The flexibility increased in a moist atmosphere due to the plasticization effect of absorbed water. The nanocomposites also exhibited significantly enhanced dynamic mechanical performance (storage modulus and glass transition temperature) than neat CO under different humidity conditions. The antibacterial activity of the films against Escherichia coli, Staphylococcus aureus, and Micrococcus luteus bacteria was investigated in the presence and the absence of UV light. The biocide effect increased progressively with the CS-ZnO content and was systematically stronger against Gram-positive cells. Composites with nanoparticle loading ≤5.0 wt % exhibited very good in vitro cytocompatibility and enabled a faster wound healing than neat CO and control gauze, hence showing great potential to be applied as antibacterial

  17. Sand-wear resistance of brush electroplated nanocomposite coating in oil and its application to remanufacturing

    Institute of Scientific and Technical Information of China (English)

    DONG Shi-yun; XU Bin-shi; DU Ling-zhong; YANG Hua

    2005-01-01

    Sand-wear resistance of nano scale alumina particle reinforced nickel matrix composite coating (n-Al2O3/ Ni) prepared by brush electroplating technique was investigated via wear tests in sand-contaminated oil lubricant,comparing with that of AISI1045 steel and brush electroplated Ni coating. Effects of testing load, sand content and sand size on worn volume of the three materials, and also coating surface roughness on worn volume of the brush electroplated coatings were accessed. Results show that the worn volume of all the three materials increases with increasing of testing load, sand content and sand size. In the same conditions, n-Al2 O3/Ni composite coating has the smallest worn volume while AISI1045 steel has the largest because of the n-Al2 O3 particle effects. As to n-Al2 O3/Ni and Ni coatings, the surface-polished coatings have obviously lower worn volume than the as-plated coatings. The brush electroplated n-Als O3/Ni composite coating was employed to remanufacture the sand-worn bearing seats of a heavy vehicle and good results were gained.

  18. Effect of alginate coatings with cinnamon bark oil and soybean oil on quality and microbiological safety of cantaloupe.

    Science.gov (United States)

    Zhang, Yue; Ma, Qiumin; Critzer, Faith; Davidson, P Michael; Zhong, Qixin

    2015-12-23

    The quality and microbiological safety of cantaloupes can potentially be improved using antimicrobial coatings that are able to maintain effectiveness throughout storage. The objective of this work was to study the effect of coating mixtures containing sodium alginate and cinnamon bark oil (CBO) on the quality of cantaloupes and the survival of inoculated bacterial pathogens and naturally occurring yeasts and molds during ambient storage at 21 °C. Cantaloupes were dipped in mixtures containing 1% sodium alginate with or without 2% CBO and 0 or 0.5% soybean oil (SBO). Weight loss and total soluble solids content of the flesh were not significantly different among coating treatments. However, changes in color and firmness of cantaloupes were delayed to different extents after coating, most significantly for the CBO+SBO treatment. Cocktails of Salmonella enterica, Escherichia coli O157:H7, or Listeria monocytogenes inoculated on cantaloupes were reduced to the detection limit (1.3 log CFU/cm(2)) and completely inhibited during the 15-day storage by the CBO+SBO treatment, while L. monocytogenes and S. enterica reached populations of 2.9 log CFU/cm(2) and 2.4 log CFU/cm(2), respectively, on cantaloupes coated with CBO alone. Antimicrobial coatings, especially with SBO, also reduced yeast and mold counts on cantaloupes by 2.6 log CFU/cm(2). SBO improved the retention of CBO during storage suggesting it is related to the enhancement of quality and microbiological safety. Findings demonstrated the potential of the antimicrobial coating system studied to improve microbiological safety and quality of cantaloupes.

  19. Monitoring of high refractive index edible oils using coated long period fiber grating sensors

    Science.gov (United States)

    Coelho, Luís.; Viegas, Diana; Santos, José Luís.; de Almeida, Jose Manuel M. M.

    2015-05-01

    Monitoring the quality of high refractive index edible oils is of great importance for the human health. Uncooked edible oils in general are healthy foodstuff, olive oil in particular, however, they are frequently used for baking and cooking. High quality edible oils are made from seeds, nuts or fruits by mechanical processes. Nevertheless, once the mechanical extraction is complete, up to 15% of the oil remains in oil pomace and in the mill wastewater, which can be extracted using organic solvents, often hexane. Optical fiber sensors based on long period fiber gratings (LPFG) have very low wavelength sensitivity when the surround refractive index is higher than the refractive index of the cladding. Titanium dioxide (TiO2) coated LPFG could lead to the realization of high sensitivity chemical sensor for the food industry. In this work LPFG coated with a TiO2 thin film were successfully used for to detect small levels of hexane diluted in edible oils and for real time monitoring the thermal deterioration of edible oils. For a TiO2 coating of 30 nm a wavelength sensitivity of 1361.7 nm/RIU (or 0.97 nm / % V/V) in the 1.4610-1.4670 refractive index range was achieved, corresponding to 0 to 12 % V/V of hexane in olive oil. A sensitivity higher than 638 nm/RIU at 225 ºC was calculated, in the 1.4670-1.4735 refractive index range with a detection limit of thermal deterioration of about 1 minute.

  20. Glycol chitosan

    DEFF Research Database (Denmark)

    Danielsen, E Thomas; Danielsen, E Michael

    2017-01-01

    Chitosan is a polycationic polysaccharide consisting of β-(1-4)-linked glucosamine units and due to its mucoadhesive properties, chemical derivatives of chitosan are potential candidates as enhancers for transmucosal drug delivery. Recently, glycol chitosan (GC), a soluble derivative of chitosan...

  1. Effects of lamination and coating with drying oils on tensile and barrier properties of zein films.

    Science.gov (United States)

    Rakotonirainy, A M; Padua, G W

    2001-06-01

    Zein films plasticized with oleic acid have been considered potentially useful for biodegradable packaging applications. However, moisture was found to affect their tensile and gas barrier properties. We investigated the effects of two converting processes, fusion lamination and coating with drying oils, on tensile properties and gas permeability of zein films. Zein films were laminated to 4-ply sheets in a Carver press and coated with tung oil, linseed oil, or a mixture of tung and soybean oils. Tensile properties and permeability to water vapor, oxygen, and carbon dioxide were measured according to ASTM methods. Laminated films were clearer, tougher, and more flexible, and had a smoother finish than nontreated sheets. Lamination decreased O(2) and CO(2) permeability by filling in voids and pinholes in the film structure. Coating increased tensile strength and elongation and decreased water vapor permeability. Coatings acted as a composite layer preventing crack propagation and increasing film strength. They also formed a highly hydrophobic surface that prevented film wetting.

  2. Advanced Anticorrosion Coating Materials Derived from Sunflower Oil with Bifunctional Properties.

    Science.gov (United States)

    Balakrishnan, Thiruparasakthi; Sathiyanarayanan, Sadagopan; Mayavan, Sundar

    2015-09-09

    High-performance barrier films preventing permeation of moisture, aggressive chloride ions, and corrosive acids are important for many industries ranging from food to aviation. In the current study, pristine sunflower oil was used to form uniform adherent films on iron (Fe) via a simple single-step thermal treatment (without involving any initiator/mediator/catalyst). Oxidation of oil on heating results in a highly conjugated (oxidized) crystalline lamellar network with interlayer separation of 0.445 nm on Fe. The electrochemical corrosion tests proved that the coating exhibits superior anticorrosion performance with high coating resistance (>10(9) ohm cm2) and low capacitance values (<10(-10) F cm(-2)) as compared to bare Fe, graphene, and conducting polymer based coatings in 1 M hydrochloric acid solutions. The electrochemical analyses reveal that the oil coatings developed in this study provided a two-fold protection of passivation from the oxide layer and barrier from polymeric films. It is clearly observed that there is no change in structure, morphology, or electrochemical properties even after a prolonged exposure time of 80 days. This work indicates the prospect of developing highly inert, environmentally green, nontoxic, and micrometer level passivating barrier coatings from more sustainable and renewable sources, which can be of interest for numerous applications.

  3. Effect of Edible and Active Coating (with Rosemary and Oregano Essential Oils) on Beef Characteristics and Consumer Acceptability

    Science.gov (United States)

    Vital, Ana Carolina Pelaes; Guerrero, Ana; Monteschio, Jessica de Oliveira; Valero, Maribel Velandia; Carvalho, Camila Barbosa; de Abreu Filho, Benício Alves; Madrona, Grasiele Scaramal; do Prado, Ivanor Nunes

    2016-01-01

    The effects of an alginate-based edible coating containing natural antioxidants (rosemary and oregano essential oils) on lipid oxidation, color preservation, water losses, texture and pH of beef steaks during 14 days of display were studied. The essential oil, edible coating and beef antioxidant activities, and beef consumer acceptability were also investigated. The edible coatings decreased lipid oxidation of the meat compared to the control. The coating with oregano was most effective (46.81% decrease in lipid oxidation) and also showed the highest antioxidant activity. The coatings significantly decreased color losses, water losses and shear force compared to the control. The coatings had a significant effect on consumer perception of odor, flavor and overall acceptance of the beef. In particular, the oregano coating showed significantly high values (approximately 7 in a 9-point scale). Active edible coatings containing natural antioxidants could improve meat product stability and therefore have potential use in the food industry. PMID:27504957

  4. Enteric-coated, pH-dependent peppermint oil capsules for the treatment of irritable bowel syndrome in children.

    Science.gov (United States)

    Kline, R M; Kline, J J; Di Palma J; Barbero, G J

    2001-01-01

    In a randomized, double-blind controlled trial, 42 children with irritable bowel syndrome (IBS) were given pH-dependent, enteric-coated peppermint oil capsules or placebo. After 2 weeks, 75% of those receiving peppermint oil had reduced severity of pain associated with IBS. Peppermint oil may be used as a therapeutic agent during the symptomatic phase of IBS.

  5. Development of palm oil-based UV-curable epoxy acrylate and urethane acrylate resins for wood coating application

    Energy Technology Data Exchange (ETDEWEB)

    Tajau, Rida; Mahmood, Mohd Hilmi; Salleh, Mek Zah; Salleh, Nik Ghazali Nik [Radiation Processing Technology Division, Malaysian Nuclear Agency (Nuclear Malaysia), Bangi, 43000 Kajang, Selangor (Malaysia); Ibrahim, Mohammad Izzat [Faculty of Science, University of Malaya (UM), 50603 Kuala Lumpur (Malaysia); Yunus, Nurulhuda Mohd [Faculty of Science and Technology, National University Malaysia (UKM), 43600 Bangi, Selangor (Malaysia)

    2014-02-12

    The trend of using renewable sources such as palm oil as raw material in radiation curing is growing due to the demand from the market to produce a more environmental friendly product. In this study, the radiation curable process was done using epoxy acrylate and urethane acrylate resins which are known as epoxidised palm olein acrylate (EPOLA) and palm oil based urethane acrylate (POBUA), respectively. The purpose of the study was to investigate curing properties and the application of this UV-curable palm oil resins for wood coating. Furthermore, the properties of palm oil based coatings are compared with the petrochemical-based compound such as ebecryl (EB) i.e. EB264 and EB830. From the experiment done, the resins from petrochemical-based compounds resulted higher degree of crosslinking (up to 80%) than the palm oil based compounds (up to 70%), where the different is around 10-15%. The hardness property from this two type coatings can reached until 50% at the lower percentage of the oligomer. However, the coatings from petrochemical-based have a high scratch resistance as it can withstand at least up to 3.0 Newtons (N) compared to the palm oil-based compounds which are difficult to withstand the load up to 1.0 N. Finally, the test on the rubber wood substrate showed that the coatings containing benzophenone photoinitiator give higher adhesion property and their also showed a higher glosiness property on the glass substrate compared to the coatings containing irgacure-819 photoinitiator. This study showed that the palm oil coatings can be a suitable for the replacement of petrochemicals compound for wood coating. The palm oil coatings can be more competitive in the market if the problems of using high percentage palm oil oligomer can be overcome as the palm oil price is cheap enough.

  6. Development of palm oil-based UV-curable epoxy acrylate and urethane acrylate resins for wood coating application

    Science.gov (United States)

    Tajau, Rida; Ibrahim, Mohammad Izzat; Yunus, Nurulhuda Mohd; Mahmood, Mohd Hilmi; Salleh, Mek Zah; Salleh, Nik Ghazali Nik

    2014-02-01

    The trend of using renewable sources such as palm oil as raw material in radiation curing is growing due to the demand from the market to produce a more environmental friendly product. In this study, the radiation curable process was done using epoxy acrylate and urethane acrylate resins which are known as epoxidised palm olein acrylate (EPOLA) and palm oil based urethane acrylate (POBUA), respectively. The purpose of the study was to investigate curing properties and the application of this UV-curable palm oil resins for wood coating. Furthermore, the properties of palm oil based coatings are compared with the petrochemical-based compound such as ebecryl (EB) i.e. EB264 and EB830. From the experiment done, the resins from petrochemical-based compounds resulted higher degree of crosslinking (up to 80%) than the palm oil based compounds (up to 70%), where the different is around 10-15%. The hardness property from this two type coatings can reached until 50% at the lower percentage of the oligomer. However, the coatings from petrochemical-based have a high scratch resistance as it can withstand at least up to 3.0 Newtons (N) compared to the palm oil-based compounds which are difficult to withstand the load up to 1.0 N. Finally, the test on the rubber wood substrate showed that the coatings containing benzophenone photoinitiator give higher adhesion property and their also showed a higher glosiness property on the glass substrate compared to the coatings containing irgacure-819 photoinitiator. This study showed that the palm oil coatings can be a suitable for the replacement of petrochemicals compound for wood coating. The palm oil coatings can be more competitive in the market if the problems of using high percentage palm oil oligomer can be overcome as the palm oil price is cheap enough.

  7. Magnetorheology of suspensions based on graphene oxide coated or added carbonyl iron microspheres and sunflower oil

    Science.gov (United States)

    Chen, Kaikai; Zhang, Wen Ling; Shan, Lei; Zhang, Xiangjun; Meng, Yonggang; Choi, Hyoung Jin; Tian, Yu

    2014-10-01

    Magnetorheological (MR) fluids based on carbonyl iron (CI) particles coated with graphene oxide (GO) and sunflower oils were studied and compared with MR fluids (MRFs) prepared with CI particles added with GO sheets. Adding GO sheets into CI had a negligible effect on the rheological properties of the MRF. Coating the spheres with GO markedly decreased the shear strength at high shear rates due to the remarkable lubricating function of the GO surface. Different behaviors were observed in the shear thickening phenomenon when the GO surface changed the mechanical interaction between particles. The results demonstrated the importance of the role of interparticle friction for MRF in shear mode and discussed the weak shear thickening phenomenon with fine lubricating coating layers and oils.

  8. Synthesis of chitosan capped copper oxide nanoleaves using high intensity (30kHz) ultrasound sonication and their application in antifouling coatings.

    Science.gov (United States)

    Abiraman, Tamilselvan; Ramanathan, Ethirajan; Kavitha, Ganapathy; Rengasamy, Ramasamy; Balasubramanian, Sengottuvelan

    2017-01-01

    The synthesis of chitosan capped copper oxide nanoleaves (CCCO NLs) was carried out under three different reaction conditions viz. 1) room temperature, 2) 70°C and 3) high intensity ultrasound (30kHz) sonication method and it has been found that the high intensity ultrasound (30kHz) sonication is the best method when compared to other two methods. The advantages of the present synthetic method are: i) easy one step process, ii) lesser reaction time, iii) good yield, iv) reproducible and v) calcination is not required. The resulting chitosan capped copper oxide nanoleaves were characterized by Diffuse Reflectance UV-Visible Spectroscopy (DRS), Fourier Transform Infra-Red Spectroscopy (FT-IR), X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Field Emission Scanning Electron Microscopy (FESEM), High Resolution Transmission Electron Microscopy (HRTEM) and Thermo gravimetric analysis (TGA). The CCCO NLs were blended with commercial paints such as polyurethane clear, polyurethane white and acrylic emulsion and applied on to three different surfaces (wood, mild steel and cement slab panels). The hydrophilicity of CCCONP coated panels was analyzed by water contact angle measurement and their antifouling behavior was investigated against three different green and marine algae viz. Arthrospira, Chlorella and Amphora. The antifouling efficiency of the CCCO NLs against the algae was found to be 78-92%.

  9. The Overcoat Oil Lubrication of Microarc Oxidation Coating on Al Alloy by Liquid Plasma Technique

    Institute of Scientific and Technical Information of China (English)

    LUO Zhuang-zi; ZHANG Zhao-zhu; LIU Wei-ming; WANG Wen-jing; TIAN Jun

    2004-01-01

    Ceramic coatings were deposited on 2Al2 alloy with a 100 kW micro-arc oxidation equipment consisting of a potential adjustable ac power supply and alkali electrolyte. The structure of the micro-arc oxidiation coatings was examined using scanning electron microscopy and transmission electron microscopy. The tribological properties of the coatings sliding against steel under the drop and adsorption lubrication of liquid paraffin were evaluated with a Timken tester. The lower friction coefficient of 0.14 and longer wear life of 2450 m of overcoat were observed for the polished micro-arc oxidation coating of 180μm thick at a sliding speed 2. 50 m/s and load 1500 N. This is because the coating has an interlayer of suitable porosity and thickness, which helps to improve the deposition of lubricants and endure the higher load. In other words, the oil is able to adsorb in the porous holes of the overcoat and provided the lubrication of micro reservoir during friction, and the compact and relatively hard interlayer of oxidation coating is able to support heavy load and prevent the oil lubricating film from damage.

  10. Removal of Petroleum Spill in Water by Chitin and Chitosan

    Directory of Open Access Journals (Sweden)

    Francisco Cláudio de Freitas Barros

    2014-05-01

    Full Text Available The present study was undertaken to evaluate the capacity of adsorption of crude oil spilled in seawater by chitin flakes, chitin powder, chitosan flakes, chitosan powder, and chitosan solution. The results showed that, although chitosan flakes had a better adsorption capacity by oil (0.379 ± 0.030 grams oil per gram of adsorbent, the biopolymer was sinking after adsorbing oil. Chitosan solution did not present such inconvenience, despite its lower adsorption capacity (0.013 ± 0.001 grams oil per gram of adsorbent. It was able to form a polymeric film on the oil slick, which allowed to restrain and to remove the oil from the samples of sea water. The study also suggests that chitosan solution 0.5% has greater efficiency against oil spills in alkaline medium than acidic medium.

  11. Effect of chitosan and its derivatives as antifungal and preservative agents on postharvest green asparagus.

    Science.gov (United States)

    Qiu, Miao; Wu, Chu; Ren, Gerui; Liang, Xinle; Wang, Xiangyang; Huang, Jianying

    2014-07-15

    The antifungal activity and effect of high-molecular weight chitosan (H-chitosan), low-molecular weight chitosan (L-chitosan) and carboxymethyl chitosan (C-chitosan) coatings on postharvest green asparagus were evaluated. L-chitosan and H-chitosan efficiently inhibited the radial growth of Fusarium concentricum separated from postharvest green asparagus at 4 mg/ml, which appeared to be more effective in inhibiting spore germination and germ tube elongation than that of C-chitosan. Notably, spore germination was totally inhibited by L-chitosan and H-chitosan at 0.05 mg/ml. Coated asparagus did not show any apparent sign of phytotoxicity and maintained good quality over 28 days of cold storage, according to the weight loss and general quality aspects. Present results inferred that chitosan could act as an attractive preservative agent for postharvest green asparagus owing to its antifungal activity and its ability to stimulate some defense responses during storage.

  12. Plum coatings of lemongrass oil-incorporating carnauba wax-based nanoemulsion.

    Science.gov (United States)

    Kim, In-Hah; Lee, Hanna; Kim, Jung Eun; Song, Kyung Bin; Lee, Youn Suk; Chung, Dae Sung; Min, Sea C

    2013-10-01

    Nanoemulsions containing lemongrass oil (LO) were developed for coating plums and the effects of the nanoemulsion coatings on the microbial safety and physicochemical storage qualities of plums during storage at 4 and 25 °C were investigated. The emulsions used for coating were produced by mixing a carnauba wax-based solution (18%, w/w) with LO at various concentrations (0.5% to 4.0%, w/w) using dynamic high pressure processing at 172 MPa. The coatings were evaluated for their ability to inhibit the growth of Salmonella Typhimurium and Escherichia coli O157:H7 and their ability to preserve various physicochemical qualities of plums. Uniform and continuous coatings on plums, formed with stable emulsions, initially inhibited S. Typhimurium and E. coli O157:H7 by 0.2 to 2.8 and 0.8 to 2.7 log CFU/g, respectively, depending on the concentration of LO and the sequence of coating. The coatings did not significantly alter the flavor, fracturability, or glossiness of the plums. The antimicrobial effects of the coatings against S. Typhimurium and E. coli O157:H7 were demonstrated during storage at 4 and 25 °C. The coatings reduced weight loss and ethylene production by approximately 2 to 3 and 1.4 to 4.0 fold, respectively, and also retarded the changes in lightness and the concentration of phenolic compounds in plums during storage. The firmness of coated plums was generally higher than uncoated plums when stored at 4 °C and plum respiration rates were reduced during storage. Coatings containing nanoemulsions of LO have the potential to inhibit Salmonella and E. coli O157:H7 contamination of plums and may extend plum shelf life.

  13. Construction of a sensitive and selective sensor for morphine using chitosan coated Fe3O4 magnetic nanoparticle as a modifier.

    Science.gov (United States)

    Dehdashtian, Sara; Gholivand, Mohammad Bagher; Shamsipur, Mojtaba; Kariminia, Samira

    2016-01-01

    A simple and sensitive sensor based on carbon paste electrode (CPE) modified by chitosan-coated magnetic nanoparticle (CMNP) was developed for the electrochemical determination of morphine (MO). The proposed sensor was characterized with scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). The electrooxidation of MO was studied on modified carbon paste electrode using cyclic voltammetry, chronoamperometry and differential pulse voltammetry as diagnostic techniques. The oxidation peak potential of morphine on the CMNP/CPE appeared at 380 mV which was accompanied with smaller overpotential and increase in oxidation peak current compared to that obtained on the bare carbon paste electrode (CPE). Under optimum conditions the sensor provides two linear DPV responses in the range of 10-2000 nM and 2-720 μM for MO with a detection limit of 3 nM. The proposed sensor was successfully applied for monitoring of MO in serum and urine samples and satisfactory results were obtained.

  14. The Applied Validated Ultraviolet-Visible Spectrophotometric Method and the Kinetic Model of the Release of Gedunin from a Chitosan-Coated Liposome

    Science.gov (United States)

    Sahu, A. Kumar; Jain, V.

    2016-11-01

    The aim of this study is to develop a simple and cost-effective ultraviolet-visible spectrophotometric method, validated according to the International Harmonization Guidelines for the determination of gedunin from a chitosan-coated liposome. The liposome was prepared using the conventional thin film hydration method. The absorption maximum in methanol was found to be 220 nm. The linearity was followed in the concentration from 5-25 μg/mL with a high correlation coefficient of 0.999. The detection and quantification limits were found to be 0.2062 and 0.6250 μg/mL. This method was shown to be precise at the intraday (relative standard deviation relative standard deviation relative standard deviation <0.4%). The results of the method robustness study indicate that the method was robust. The method was used to determine encapsulation efficiency and the release profile from a coated liposome. Kinetic models (zero order, first order, Higuchi, Hixson-Crowell, and Korsmeyer-Peppas) were used to fit the obtained release profile and to predict the in vivo performance of a Gedunin containing coated liposome.

  15. Magnesium oxide prepared via metal-chitosan complexation method: Application as catalyst for transesterification of soybean oil and catalyst deactivation studies

    Science.gov (United States)

    Almerindo, Gizelle I.; Probst, Luiz F. D.; Campos, Carlos E. M.; de Almeida, Rusiene M.; Meneghetti, Simoni M. P.; Meneghetti, Mario R.; Clacens, Jean-Marc; Fajardo, Humberto V.

    2011-10-01

    A simple method to prepare magnesium oxide catalysts for biodiesel production by transesterification reaction of soybean oil with ethanol is proposed. The method was developed using a metal-chitosan complex. Compared to the commercial oxide, the proposed catalysts displayed higher surface area and basicity values, leading to higher yield in terms of fatty acid ethyl esters (biodiesel). The deactivation of the catalyst due to contact with CO2 and H2O present in the ambient air was verified. It was confirmed that the active catalytic site is a hydrogenocarbonate adsorption site.

  16. Efficacy of a coating composed of chitosan from Mucor circinelloides and carvacrol to control Aspergillus flavus and the quality of cherry tomato fruits.

    Science.gov (United States)

    de Souza, Evandro L; Sales, Camila V; de Oliveira, Carlos E V; Lopes, Laênia A A; da Conceição, Maria L; Berger, Lúcia R R; Stamford, Thayza C M

    2015-01-01

    Cherry tomato (Lycopersicon esculentum Mill) fruits are susceptible to contamination by Aspergillus flavus, which may cause the development of fruit rot and significant postharvest losses. Currently there are significant drawbacks for the use of synthetic fungicides to control pathogenic fungi in tomato fruits, and it has increased the interest in exploring new alternatives to control the occurrence of fungal infections in these fruits. This study evaluated the efficacy of chitosan (CHI) from Mucor circinelloides in combination with carvacrol (CAR) in inhibiting A. flavus in laboratory media and as a coating on cherry tomato fruits (25°C, 12 days and 12°C, 24 days). During a period of storage, the effect of coatings composed of CHI and CAR on autochthonous microflora, as well as on some quality characteristics of the fruits such as weight loss, color, firmness, soluble solids, and titratable acidity was evaluated. CHI and CAR displayed MIC valuesof 7.5 mg/mL and 10 μL/mL, respectively, against A. flavus. The combined application of CHI (7.5 or 3.75 mg/mL) and CAR (5 or 2.5 μL/mL) strongly inhibited the mycelial growth and spore germination of A. flavus. The coating composed of CHI (3.75 mg/mL) and CAR (2.5 or 1.25 μL/mL) inhibited the growth of A. flavus in artificially contaminated fruits, as well as the native fungal microflora of the fruits stored at room or low temperature. The application of the tested coatings preserved the quality of cherry tomato fruits as measured by some physicochemical attributes. From this, composite coatings containing CHI and CAR offer a promising alternative to control postharvest infection caused by A. flavus or native fungal microflora in fresh cherry tomato fruits without negatively affecting their quality over storage.

  17. Efficacy of a coating composed of chitosan from Mucor circinelloides and carvacrol to control Aspergillus flavus and the quality of cherry tomato fruits

    Science.gov (United States)

    de Souza, Evandro L.; Sales, Camila V.; de Oliveira, Carlos E. V.; Lopes, Laênia A. A.; da Conceição, Maria L.; Berger, Lúcia R. R.; Stamford, Thayza C. M.

    2015-01-01

    Cherry tomato (Lycopersicon esculentum Mill) fruits are susceptible to contamination by Aspergillus flavus, which may cause the development of fruit rot and significant postharvest losses. Currently there are significant drawbacks for the use of synthetic fungicides to control pathogenic fungi in tomato fruits, and it has increased the interest in exploring new alternatives to control the occurrence of fungal infections in these fruits. This study evaluated the efficacy of chitosan (CHI) from Mucor circinelloides in combination with carvacrol (CAR) in inhibiting A. flavus in laboratory media and as a coating on cherry tomato fruits (25°C, 12 days and 12°C, 24 days). During a period of storage, the effect of coatings composed of CHI and CAR on autochthonous microflora, as well as on some quality characteristics of the fruits such as weight loss, color, firmness, soluble solids, and titratable acidity was evaluated. CHI and CAR displayed MIC valuesof 7.5 mg/mL and 10 μL/mL, respectively, against A. flavus. The combined application of CHI (7.5 or 3.75 mg/mL) and CAR (5 or 2.5 μL/mL) strongly inhibited the mycelial growth and spore germination of A. flavus. The coating composed of CHI (3.75 mg/mL) and CAR (2.5 or 1.25 μL/mL) inhibited the growth of A. flavus in artificially contaminated fruits, as well as the native fungal microflora of the fruits stored at room or low temperature. The application of the tested coatings preserved the quality of cherry tomato fruits as measured by some physicochemical attributes. From this, composite coatings containing CHI and CAR offer a promising alternative to control postharvest infection caused by A. flavus or native fungal microflora in fresh cherry tomato fruits without negatively affecting their quality over storage. PMID:26257717

  18. Effect of nano-composite and Thyme oil (Tymus Vulgaris L) coating on fruit quality of sweet cherry (Takdaneh Cv) during storage period.

    Science.gov (United States)

    Nabifarkhani, Naser; Sharifani, Mehdi; Daraei Garmakhany, Amir; Ganji Moghadam, Ebrahim; Shakeri, Alireza

    2015-07-01

    Sweet cherry is one of the most appreciated fruit by consumers since it is an early season fruit and has an excellent quality. In this study effect of active nano composite formed from chitosan (as a matrix material), nano cellulose fiber (1% concentration) and Thyme oils (Tymus Vulgaris L) at 1% concentration on fruits quality was investigated. Treated fruits were stored at 1°C for 5 weeks and changes of different qualities attributes including weight loss, total acidity, TSS, anthocyanin, total sugar and malic acid content (by high performance liquid chromatography (HPLC) method) were measured each week. Results showed that nano composite and Thyme oil significantly affect fruit's water retention and so decrease fruit weight loss and preserve anthocyanin (P < 0.05). None of applied treatments had any significant effects in comparison with control in regard to acidity while total sugar content and TSS significantly affected by treatment compared to control samples. Result of HPLC analysis showed that there was no significant difference between different treatment and control sample in term of malic acid concentrations during storage period but increase storage time lead to increase malic acid concentration in all treatments. For conclusion it can be Saied that fruits coating with nano-composite, lead to increase fruit shelf life, better appearance and prevents fungal growth that may be due to creation of an active packaging by these compounds.

  19. Cleaning of Oil Fouling with Water Enabled by Zwitterionic Polyelectrolyte Coatings: Overcoming the Imperative Challenge of Oil-Water Separation Membranes.

    Science.gov (United States)

    He, Ke; Duan, Haoran; Chen, George Y; Liu, Xiaokong; Yang, Wensheng; Wang, Dayang

    2015-09-22

    Herein we report a self-cleaning coating derived from zwitterionic poly(2-methacryloyloxylethyl phosphorylcholine) (PMPC) brushes grafted on a solid substrate. The PMPC surface not only exhibits complete oil repellency in a water-wetted state (i.e., underwater superoleophobicity), but also allows effective cleaning of oil fouled on dry surfaces by water alone. The PMPC surface was compared with typical underwater superoleophobic surfaces realized with the aid of surface roughening by applying hydrophilic nanostructures and those realized by applying smooth hydrophilic polyelectrolyte multilayers. We show that underwater superoleophobicity of a surface is not sufficient to enable water to clean up oil fouling on a dry surface, because the latter circumstance demands the surface to be able to strongly bond water not only in its pristine state but also in an oil-wetted state. The PMPC surface is unique with its described self-cleaning performance because the zwitterionic phosphorylcholine groups exhibit exceptional binding affinity to water even when they are already wetted by oil. Further, we show that applying this PMPC coating onto steel meshes produces oil-water separation membranes that are resilient to oil contamination with simply water rinsing. Consequently, we provide an effective solution to the oil contamination issue on the oil-water separation membranes, which is an imperative challenge in this field. Thanks to the self-cleaning effect of the PMPC surface, PMPC-coated steel meshes can not only separate oil from oil-water mixtures in a water-wetted state, but also can lift oil out from oil-water mixtures even in a dry state, which is a very promising technology for practical oil-spill remediation. In contrast, we show that oil contamination on conventional hydrophilic oil-water separation membranes would permanently induce the loss of oil-water separation function, and thus they have to be always used in a completely water-wetted state, which significantly

  20. Electrospraying of water in oil emulsions for thin film coating

    NARCIS (Netherlands)

    Khan, M.K.I.; Maan, A.A.; Schutyser, M.A.I.; Schroën, C.G.P.H.; Boom, R.M.

    2013-01-01

    Electrospraying of water-in-oil emulsions was investigated to produce thin edible barriers. A reproducible model surface was used, namely cellulose membranes of which permeability is well-established. PGPR-based emulsions were stable during electrospraying and produced a fine stable jet spray; emuls

  1. Oil-acrylic hybrid latexes as binders for waterborne coatings

    NARCIS (Netherlands)

    Hamersveld, van E.M.S.; Es, van J.; German, A.L.; Cuperus, F.P.; Weissenborn, P.; Hellgren, A.C.

    1999-01-01

    The combination of the characteristics of oil, or alkyd, emulsions and acrylic latexes in a waterborne binder has been the object of various studies in the past. Strategies for combining the positive properties of alkyds, e.g. autoxidative curing, gloss and penetration in wood, with the fast drying

  2. Separation of water and oil by poly (acrylic acid)-coated stainless steel mesh prepared by radiation crosslinking

    Energy Technology Data Exchange (ETDEWEB)

    Nho, Young Chang; Shin, Jung Woong; Park, Jong Seok; Lim, Young Mook; Jeun, Joon Pyo; Kang, Phil Hyun [Research Division for Industry and Environment, Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2015-05-15

    The stainless steel mesh coated with poly(acrylic acid) hydrogel was fabricated and applied for the separation of water and oil. The stainless steel mesh was immersed in aqueous poly (acrylic acid) solution, and then irradiated by radiation to introduce poly(acrylic acid) hydrogel on the surface of mesh by crosslinking. It was possible to separate oil and water from mixtures of oil/water effectively using the hydrogel-coated mesh. The effect of irradiation dose, coating thickness, size of mesh on the separation efficiency was examined.

  3. New multilayer coating using quaternary ammonium chitosan and κ-carrageenan in capillary electrophoresis: application in fast analysis of betaine and methionine.

    Science.gov (United States)

    Vitali, Luciano; Della Betta, Fabiana; Costa, Ana Carolina O; Vaz, Fernando Antonio Simas; Oliveira, Marcone Augusto Leal; Vistuba, Jacqueline Pereira; Fávere, Valfredo T; Micke, Gustavo A

    2014-06-01

    The aim of this study was to develop a new multilayer coating with crosslinked quaternary ammonium chitosan (hydroxypropyltrimethyl ammonium chloride chitosan; HACC) and κ-carrageenan for use in capillary electrophoresis. A new semi-permanent multilayer coating was formed using the procedure developed and the method does not require the presence of polymers in the background electrolyte (BGE). The new capillary multilayer coating showed a cathodic electroosmotic flow (EOF) of around 30×10(-9) m(2) V(-1) s(-1) which is pH-independent in the range of pH 2 to 10. The enhanced EOF at low pH obtained contributed significantly to the development of a fast method of separation. The multilayer coating was then applied in the development of a fast separation method to determine betaine and methionine in pharmaceutical formulations by capillary zone electrophoresis (CZE). The BGE used to determine the betaine and methionine concentrations was composed of 10 mmol L(-1) tris(hydroxymethyl) aminomethane, 40 mmol L(-1) phosphoric acid and 10% (v/v) ethanol, at pH 2.1. A fused-silica capillary of 32 cm (50 µm ID×375 µm OD) was used in the experiments and samples and standards were analyzed employing the short-end injection procedure (8.5 cm effective length). The instrumental analysis time of the optimized method was 1.53 min (approx. 39 runs per hour). The validation of the proposed method for the determination of betaine and methionine showed good linearity (R(2)>0.999), adequate limit of detection (LOD <8 mg L(-1)) for the concentration in the samples and inter-day precision values lower than 3.5% (peak area and time migration). The results for the quantification of the amino acids in the samples determined by the CZE-UV method developed were statistically equal to those obtained with the comparative LC-MS/MS method according to the paired t-test with a confidence level of 95%.

  4. Antimicrobial Nanostructured Bioactive Coating Based on Fe3O4 and Patchouli Oil for Wound Dressing

    Directory of Open Access Journals (Sweden)

    Marius Rădulescu

    2016-04-01

    Full Text Available The aim of this study was to develop a biocompatible coating for wound dressings, containing iron oxide nanoparticles functionalized with patchouli essential oil in order to obtain improved antimicrobial properties able to prevent biofilm development and consecutive associated infections. The bioactive coating was prepared by the co-precipitation of a precursor in an alkaline solution of patchouli oil. The prepared surface was characterized by XRD (X ray diffraction, TEM (transmission electron microscopy, SAED (selected area diffraction, SEM (scanning electron microscopy and FT-IR (Fourier transform infrared spectroscopy. The bioevaluation of the obtained coating consisted in antimicrobial, as well as in vitro and in vivo biocompatibility and biodistribution assays. The obtained coating revealed a strong anti-biofilm activity maintained up to 72 h, as well as a low cytotoxicity on mammalian cells and a good biodistribution after intraperitoneal injection in mice. These results demonstrate the promising potential of the respective coatings for the management of wound infections and for the development of soft materials with improved resistance to microbial colonization.

  5. A novel composite coating mesh film for oil-water separation

    Institute of Scientific and Technical Information of China (English)

    Futao QIN; Zhijia YU; Xinhui FANG; Xinghua LIU; Xiangyu SUN

    2009-01-01

    Polytetrafluoroethylene-polyphenylene sulfide composite coating mesh film was successfully prepared by a simple layered transitional spray-plasticizing method on a stainless steel mesh. It shows super-hydrophobic and super-oleophilic properties. The contact angle of this mesh film is 156.3° for water, and close to 0° for diesel oil and kerosene. The contact angle hysteresis of water on the mesh film is 4.3°. The adhesive force between the film and substrate is grade 0, the flexibility is 1 mm and the pencil hardness is 4H. An oil-water separation test was car-fled out for oil-contaminated water in a six-stage super-hydrophobic film separator. The oil removal rate can reach about 99%.

  6. Pegasus project. DLC coating and low viscosity oil reduce energy losses significantly

    Energy Technology Data Exchange (ETDEWEB)

    Doerwald, Dave; Jacobs, Ruud [Hauzer Techno Coating (Netherlands). Tribological Coatings

    2012-03-15

    Pegasus, the flying horse from Greek mythology, is a suitable name for the research project initiated by a German automotive OEM with participation of Hauzer Techno Coating and several automotive suppliers. It will enable future automotive vehicles to reduce fuel consumption without losing power. The project described in this article focuses on the rear differential, because reducing friction here can contribute considerably to efficiency improvement of the whole vehicle. Surfaces, coating and oil viscosity have been investigated and interesting conclusions have been reached. (orig.)

  7. Efficient mucus permeation and tight junction opening by dissociable "mucus-inert" agent coated trimethyl chitosan nanoparticles for oral insulin delivery.

    Science.gov (United States)

    Liu, Min; Zhang, Jian; Zhu, Xi; Shan, Wei; Li, Lian; Zhong, Jiaju; Zhang, Zhirong; Huang, Yuan

    2016-01-28

    Oral administration of protein drugs is greatly impeded by the lack of drug carriers that can efficiently overcome the absorption barriers of mucosa tissue, which consists of not only epithelium but also a blanket of mucus gel. We herein report a novel self-assembled nanoparticle (NP) platform for oral delivery of insulin by facilitating the efficient permeation through both of these two barriers. The NP possesses a core composed of insulin and trimethyl chitosan (TMC), and a dissociable "mucus-inert" hydrophilic coating of N-(2-hydroxypropyl) methacrylamide copolymer (pHPMA) derivative. The NPs exhibited free Brownian motion and excellent permeability in mucus, which enabled the access of the NP core to the epithelial cell surface underneath the mucus. Moreover, investigation of NP behavior showed that the pHPMA molecules started to dissociate as the NP permeates through mucus, and the TMC NP core was then exposed to facilitate transepithelial transport via paracellular pathway. The pHPMA coating significantly improved transepithelial transport of TMC-based NP and their ability to open tight junctions between the mucus-secreting epithelial cells. Moreover, in diabetic rats, pHPMA coated NPs generated a prominent hypoglycemic response following oral administration, and exhibited a relative bioavailability 2.8-fold higher than that of uncoated TMC-based NPs. Our study provided the evidence of using pHPMA as "mucus-inert" agent to enhance mucus permeation of TMC-based NPs, and validated a novel strategy to overcome the multiple absorption barriers using NP platform with dissociable hydrophilic coating and TMC-based core possessing tight junction-opening ability.

  8. Antibacterial Effect of Carboxymethyl Cellulose Coating Enriched by Zataria Multiflora Essential Oil and Grape Seed Extract

    Directory of Open Access Journals (Sweden)

    Raeisi, M.

    2012-01-01

    Full Text Available Background and objectives: The presence of pathogenicbacteria and the factors causing food spoilage are the greatchallenge for public health. Attention to natural additivesinstead of chemical preservatives resulted in conducting severalstudies on plant essential oil and extracts. We aimed atevaluating the antibacterial effect of carboxymethyl cellulosecoating enriched by Zataria multiflora essential oil and grapeseed extract on rainbow trout meat.Material and methods: In this study, two concentrations ofZataria multiflora essential oil (1% and 2% and twoconcentrations of grape seed extract (0.5% and 1% were usedboth alone and in combination with Carboxymethyl cellulosecoating. Antibacterial effect of these treatments was evaluatedby enumeration of bacteria in special culture media.Results: The results obtained in this study demonstrate thatZataria multiflora essential oil in combination with grape seedextract significantly can decrease the number of bacteria anddelay the spoilage of the samples (p<0.05.Conclusion: Coating enriched by Zataria multiflora and grapeseed extract can properly delay the growth of spoilagemicroorganisms and prolong the shelf life of meat products.Key words: Carboxymethyl cellulose coating, Zatariamultiflora essential oil, Grape seed extract, Microbial flora

  9. Molecular modeling of interactions between heavy crude oil and the soil organic matter coated quartz surface.

    Science.gov (United States)

    Wu, Guozhong; Zhu, Xinzhe; Ji, Haoqing; Chen, Daoyi

    2015-01-01

    Molecular dynamic (MD) simulation was applied to evaluate the mobility, diffusivity and partitioning of SARA (saturates, aromatics, resins, asphaltenes) fractions of heavy crude oil on soil organic matter (SOM) coated quartz surface. Four types of SOM were investigated including Leonardite humic acid, Temple-Northeastern-Birmingham humic acid, Chelsea soil humic acid and Suwannee river fulvic acid. The SOM aggregation at oil-quartz interface decreased the adsorption of SARA on the quartz surface by 13-83%. Although the SOM tended to promote asphaltenes aggregation, the overall mobility of SARA was significantly greater on SOM-quartz complex than on pure quartz. Particularly, the diffusion coefficient of asphaltenes and resins increased by up to one-order of magnitude after SOM addition. The SOM increased the overall oil adsorption capacity but also mobilized SARA by driving them from the viscous oil phase and rigid quartz to the elastic SOM. This highlighted the potential of SOM addition for increasing the bioavailability of heavy crude oil without necessarily increasing the environmental risks. The MD simulation was demonstrated to be helpful for interpreting the role of SOM and the host oil phase for the adsorption and partitioning of SARA molecules, which is the key for developing more realistic remediation appraisal for heavy crude oil in soils.

  10. Surface modification of an Mg-1Ca alloy to slow down its biocorrosion by chitosan.

    Science.gov (United States)

    Gu, X N; Zheng, Y F; Lan, Q X; Cheng, Y; Zhang, Z X; Xi, T F; Zhang, D Y

    2009-08-01

    The surface morphologies before and after immersion corrosion test of various chitosan-coated Mg-1Ca alloy samples were studied to investigate the effect of chitosan dip coating on the slowdown of biocorrosion. It showed that the corrosion resistance of the Mg-Ca alloy increased after coating with chitosan, and depended on both the chitosan molecular weight and layer numbers of coating. The Mg-Ca alloy coated by chitosan with a molecular weight of 2.7 x 10(5) for six layers has smooth and intact surface morphology, and exhibits the highest corrosion resistance in a simulated body fluid.

  11. Surface modification of an Mg-1Ca alloy to slow down its biocorrosion by chitosan

    Energy Technology Data Exchange (ETDEWEB)

    Gu, X N; Zheng, Y F; Lan, Q X [State Key Laboratory for Turbulence and Complex System and College of Engineering, Peking University, Beijing 100871 (China); Cheng, Y; Xi, T F [Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871 (China); Zhang, Z X [Biomedical Engineering Research Center, Research Institute of Peking University in Shenzhen, Shenzhen 518057 (China); Zhang, D Y, E-mail: gxn139888@pku.edu.c, E-mail: yfzheng@pku.edu.c, E-mail: 8lanqiuxiang@163.co, E-mail: chengyan@pku.edu.c, E-mail: top5460@163.co, E-mail: xitingfei@tom.co, E-mail: zhangdeyuan@lifetechmed.co [Lifetech Scientific (Shenzhen) Co. Ltd, Hi-Tech Park, Shenzhen 518000 (China)

    2009-08-15

    The surface morphologies before and after immersion corrosion test of various chitosan-coated Mg-1Ca alloy samples were studied to investigate the effect of chitosan dip coating on the slowdown of biocorrosion. It showed that the corrosion resistance of the Mg-Ca alloy increased after coating with chitosan, and depended on both the chitosan molecular weight and layer numbers of coating. The Mg-Ca alloy coated by chitosan with a molecular weight of 2.7 x 10{sup 5} for six layers has smooth and intact surface morphology, and exhibits the highest corrosion resistance in a simulated body fluid.

  12. Spreading Behaviour of Silicone Oil and Glycerol Drops on Coated Papers

    Directory of Open Access Journals (Sweden)

    Mohammad Ilyas KHAN

    2009-07-01

    Full Text Available The effect of physical properties represented by viscosity and surface tension of liquid spreading on coated papers was investigated. Two substrates of different surface roughness were used to study the spreading behaviour of silicon oil and glycerine/water solutions in terms of contact angle, wetted drop base area and drop height as a function of time. The liquid spreading on coated papers was found to vary depending on the liquid physical properties. Liquids with lower surface tension (silicon oil and viscosity prevailed better wettability and vice versa. High surface roughness reduced the liquid spreading. Despite being traditionally used as a wetting indicator, contact angles were found to be insufficient to evaluate the spreading of liquids on these substrates. Hence, other parameters such as drop base area and drop height should also be considered.

  13. Development of novel cationic chitosan- and anionic alginate–coated poly(D,L-lactide-co-glycolide nanoparticles for controlled release and light protection of resveratrol

    Directory of Open Access Journals (Sweden)

    Sanna V

    2012-10-01

    Full Text Available Vanna Sanna,1 Anna Maria Roggio,1 Silvia Siliani,1 Massimo Piccinini,1 Salvatore Marceddu,2 Alberto Mariani,3 Mario Sechi31Porto Conte Ricerche, Alghero, Italy; 2Istituto di Scienze delle Produzioni Alimentari (ISPA, Consiglio Nazionale delle Ricerche (CNR, Sezione di Sassari, Italy; 3Department of Chemistry and Pharmacy, University of Sassari, Sassari, ItalyBackground: Resveratrol, like other natural polyphenols, is an extremely photosensitive compound with low chemical stability, which limits the therapeutic application of its beneficial effects. The development of innovative formulation strategies, able to overcome physicochemical and pharmacokinetic limitations of this compound, may be achieved via suitable carriers able to associate controlled release and protection. In this context, nanotechnology is proving to be a powerful strategy. In this study, we developed novel cationic chitosan (CS- and anionic alginate (Alg-coated poly(d,l-lactide-co-glycolide nanoparticles (NPs loaded with the bioactive polyphenolic trans-(E-resveratrol (RSV for biomedical applications.Methods: NPs were prepared by the nanoprecipitation method and characterized in terms of morphology, size and zeta potential, encapsulation efficiency, Raman spectroscopy, swelling properties, differential scanning calorimetry, and in vitro release studies. The protective effect of the nanosystems under the light-stressed RSV and long-term stability were investigated.Results: NPs turned out to be spherical in shape, with size ranging from 135 to about 580 nm, depending on the composition and the amount of polyelectrolytes, while the encapsulation efficiencies increased from 8% of uncoated poly(d,l-lactide-co-glycolide (PLGA to 23% and 32% of Alg- and CS-coated PLGA NPs, respectively. All nanocarriers are characterized by a biphasic release pattern, and more effective controlled release rates are obtained for NPs formulated with higher polyelectrolyte concentrations. Stability

  14. Poly(lactic acid) nanoparticles coated with combined WGA and water-soluble chitosan for mucosal delivery of β-galactosidase.

    Science.gov (United States)

    Sheng, Yan; He, Hongjun; Zou, Hui

    2014-08-01

    A combinatorial design, physical adsorption of water-soluble chitosan (WSC) to particle surface and covalent conjugation of wheat germ agglutinin (WGA) to WSC, was applied to surface modification of poly(lactic acid) nanoparticles (NPs) for targeted delivery of β-galactosidase to the intestinal mucosa. All the surface-engineered NPs in the size range of 500-600 nm were prepared by a w/o/w solvent diffusion/evaporation technique. β-Galactosidase encapsulated in these NPs was well protected from external proteolysis and exerted high hydrolytic activity on the permeable lactose. The presence of WSC coating, whether alone or with WGA, highly improved the suspension stability of NPs and tailored the particle surface positively charged. In comparison to NPs modified with WGA or WSC alone, the synergistic action of WGA and WSC greatly enhanced the NP-mucin interactions in vitro. The highest amount of NPs was found in the small intestine at 24 h after oral administration in rats. Notably, calculated half-life of WGA-WSC-NPs in the small intestine was 6.72 h, resulting in 2.1- and 4.3-fold increase when compared to WGA-polyvinylalcohol (PVA)-NPs and WSC-NPs, much longer than that of control PVA-NPs (6.9-fold). These results suggest that NPs with the combined WGA and WSC coating represent promising candidates for efficient mucosal drug delivery as well as biomimetic treatment of lactose intolerance.

  15. Effects and Mechanism of Chitosan Coatings in the Control of Superficial Scald in Apples%壳聚糖涂膜对苹果虎皮病防治效果与机理研究

    Institute of Scientific and Technical Information of China (English)

    吕新刚; 刘兴华; 蔡露阳

    2011-01-01

    The effects of chitosan coatings on the control of superficial scald in " Fuji" apples were investigated, and the dynamic changes in a-farnesene production and oxidation, the texture and function of cell membrane and the activity of enzyme related with browning were also measured to reveal the mechanism of chitosan coatings in the superficial scald control. The results indicated that by chitosan coatings, the respiration rate and the ethylene production were inhibited, the production of a-farnesene and the accumulation of conjugated trienes were reduced, membrane lipid peroxidation was weakened and the integrity of cell membrane was kept, and the increase of polyphenoloxidase ( PPO) activities was inhibited, the chitosan coating could effectively control the superficial scald in apples.%以红富士苹果为试材,研究了壳聚糖涂膜处理对苹果虎皮病的防治效果,并从α-法尼烯的生成及氧化、膜结构和功能及褐变相关酶活性变化3个方面探讨壳聚糖涂膜对贮藏过程中苹果生理变化的影响,以揭示其对虎皮病的作用机理.结果表明:壳聚糖涂膜可以抑制果实呼吸作用和乙烯的生成,降低α-法尼烯生成及氧化产物共轭三烯的积累,降低膜脂过氧化作用,较好地保持细胞膜的完整性,抑制PPO活性的升高;壳聚糖涂膜处理对虎皮病有明显的防治作用.

  16. Development of wear resistant nanostructured duplex coatings by high velocity oxy-fuel process for use in oil sands industry.

    Science.gov (United States)

    Saha, Gobinda C; Khan, Tahir I; Glenesk, Larry B

    2009-07-01

    Oil sands deposits in Northern Alberta, Canada represent a wealth of resources attracting huge capital investment and significant research focus in recent years. As of 2005, crude oil production from the current oil sands operators accounted for 50% of Canada's domestic production. Alberta's oil sands deposits contain approximately 1.7 trillion barrels of bitumen, of which over 175 billion are recoverable with current technology, and 315 billion barrels are ultimately recoverable with technological advances. A major problem of operating machinery and equipment in the oil sands is the unpredictable failure from operating in this highly aggressive environment. One of the significant causes of that problem is premature material wear. An approach to minimize this wear is the use of protective coatings and, in particular, a cermet thin coating. A high level of coating homogeneity is critical for components such as bucketwheels, draglines, conveyors, shovels, heavyhauler trucks etc. that are subjected to severe degradation through abrasive wear. The identification, development and application of optimum wear solutions for these components pose an ongoing challenge. Nanostructured cermet coatings have shown the best results of achieving the degree of homogeneity required for these applications. In this study, WC-17Co cermet powder with nanocrystalline WC core encapsulated with 'duplex' Co layer was used to obtain a nanostructured coating. To apply this coating, high velocity oxy-fuel (HVOF) thermal spraying technique was used, as it is known for producing wear-resistant coatings superior to those obtained from plasma-based techniques. Mechanical, sliding wear and microstructural behavior of the coating was compared with those of the microstructured coating obtained from spraying WC-10Co-4Cr cermet powder by HVOF technique. Results from the nanostructured coating, among others, showed an average of 25% increase in microhardness, 30% increase in sliding wear resistance and

  17. Tribological Performance of Hydrogenated Amorphous Carbon (a-C: H DLC Coating when Lubricated with Biodegradable Vegetal Canola Oil

    Directory of Open Access Journals (Sweden)

    H.M. Mobarak

    2014-06-01

    Full Text Available Increasing environmental awareness and demands for lowering energy consumptions are strong driving forces behind the development of the vehicles of tomorrow. Without the advances of lubricant chemistry and adequate lubricant formulation, expansion of modern engines would not have been possible. Considering environmental awareness factors as compared to mineral oils, vegetal oil based biolubricants are renewable, biodegradable, non-toxic and have a least amount of greenhouse gases. Furthermore, improvement in engine performance and transmission components, which were impossible to achieve by applying only lubricants design, is now possible through diamond like carbon (DLC coatings. DLC coatings exhibit brilliant tribological properties, such as good wear resistance and low friction. In this regard, tribological performance of a-C: H DLC coating when lubricated with Canola vegetal oil has been investigated by the help of a ball-on-flat geometry. Experimental results demonstrated that the a-C: H DLC coating exhibited better performance with Canola oil in terms of friction and wear as compared to the uncoated materials. Large amount of polar components in the Canola oil significantly improved the tribological properties of the a-C:H coating. Thus, usage of a-C: H DLC coating with Canola oil in the long run may have a positive impact on engine life.

  18. Influence of solid contaminants in oil on wear characteristics of nano-Al2O3/Ni composite coating

    Institute of Scientific and Technical Information of China (English)

    杜令忠; 徐滨士; 董世运; 杨华; 吴毅雄

    2004-01-01

    Solid contaminants in lubrication system will cause severe wear of sliding components. In order to improve the wear resistance of the material in oil containing solid contaminants, the brush plated nano-A12 O3/Ni composite coating was prepared and the influence of the sand content and sand size on the tribological property of the coating in oil containing solid contaminants was tested with ball-on-disc tester. The results show that the wear volume increases with increasing the sand content and sand size, and the wear resistance of the composite coating is 20% higher than that of the high-speed plain nickel coating. The main wear mechanisms of the coatings are abrasive wear and adhesive wear. And due to the nano-particle strengthening effect, the wear resistance of the composite coating is improved.

  19. Moisture-Thermo-Resistant Properties of Starch-Based Composite Coating with Chitosan%壳聚糖涂布淀粉基复合材料的耐湿热性能

    Institute of Scientific and Technical Information of China (English)

    林宝凤; 黎演明; 周妤莲; 李磊; 杜予民

    2011-01-01

    Starch-based composite coating with chitosan was prepared through blend under hot-pressing and coating treatment. The Fourier transform infrared spectrum(FT-IR) and scanning electron microscope (SEM) results show that the blend has a good compatibility, strong hydrogen bond exists between chitosan and other components resulting to form compact coating on the surface of composition. The moisture-thermo-resistant properties of the composite have been researched by two different moisture heat treatment methods. It is indicated that the moisture-thermo-resistant properties obviously improves after coating with chitosan. Coating chitosan can decrease the water absorption from 72.5 % to 40.3 % and increase the rate of remaining tensile strength from 62.9 %to 95.7 % after the composites have been treatment in water vapor for 30 min; Coating chitosan also can increase the rate of remaining tensile strength from 15.9 % to 39.9 % after socked in water of 50 ℃ for 30 min.%采用热压共混、涂布的方法制备了壳聚糖涂布淀粉基复合材料.红外光谱和扫描电镜研究表明该复合材料有着良好的相容性,壳聚糖溶液与基材间通过氢键作用而形成致密涂层;用两种湿热处理方法研究了该复合材料的耐湿热性能,结果显示,壳聚糖涂布能显著提高材料的耐湿热性能.经水蒸汽熏蒸30 min后,壳聚糖涂布使材料的吸水率从72.5%降低至40.3%,拉伸强度保留率由62.9%提高至95.7%.经50℃水浸泡30 min后,壳聚糖涂布使材料的拉伸强度保留率由15.5%提高至39.9%.

  20. Chitosan as an edible invisible film for quality preservation of herring and atlantic cod.

    Science.gov (United States)

    Jeon, You-Jin; Kamil, Janak Y V A; Shahidi, Fereidoon

    2002-08-28

    The effect of chitosan with different molecular weights as coatings for shelf-life extension of fresh fillets of Atlantic cod (Gadus morhua) and herring (Clupea harengus) was evaluated over a 12-day storage at refrigerated temperature (4 +/- 1 degrees C). Three chitosan preparations from snow crab (Chinoecetes opilio) processing wastes, differing in viscosities and molecular weights, were prepared; their apparent viscosities (360, 57, and 14 cP) depended on the deacetylation time (4, 10, and 20 h, respectively) of the chitin precursor. Upon coating with chitosans, a significant (p chitosan after 4, 6, 8, 10, and 12 days of storage, respectively. Chitosan coating significantly (p chitosan were inter-related; the efficacy of chitosans with viscosities of 57 and 360 cP was superior to that of chitosan with a 14 cP viscosity. Thus, chitosan as edible coating would enhance the quality of seafoods during storage.

  1. Design and construction of polymerized-chitosan coated Fe{sub 3}O{sub 4} magnetic nanoparticles and its application for hydrophobic drug delivery

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Yongling [Key Laboratory for Liquid–solid Structural Evolution and Processing of Materials (Ministry of Education), Engineering Ceramics Key Laboratory of Shandong Province, Shandong University, Jinan 250061 (China); School of Materials Science and Engineering, University of Jinan, Jinan 250022 (China); Shen, Shirley Z. [Materials Science and Engineering, CSIRO, Highett Vic 3190 (Australia); Sun, Huadong [College of Chemical Engineering, China University of Petroleum, Qing Dao 266555 (China); Sun, Kangning, E-mail: sunkangning@sdu.edu.cn [Key Laboratory for Liquid–solid Structural Evolution and Processing of Materials (Ministry of Education), Engineering Ceramics Key Laboratory of Shandong Province, Shandong University, Jinan 250061 (China); School of Materials Science and Engineering, University of Jinan, Jinan 250022 (China); Liu, Futian, E-mail: mse_liuft@ujn.edu.cn [Key Laboratory for Liquid–solid Structural Evolution and Processing of Materials (Ministry of Education), Engineering Ceramics Key Laboratory of Shandong Province, Shandong University, Jinan 250061 (China); School of Materials Science and Engineering, University of Jinan, Jinan 250022 (China); Qi, Yushi; Yan, Jun [School of Materials Science and Engineering, University of Jinan, Jinan 250022 (China)

    2015-03-01

    In this study, a novel hydrogel, chitosan (CS) crosslinked carboxymethyl-β-cyclodextrin (CM-β-CD) polymer modified Fe{sub 3}O{sub 4} magnetic nanoparticles was synthesized for delivering hydrophobic anticancer drug 5-fluorouracil (CS-CDpoly-MNPs). Carboxymethyl-β-cyclodextrin being grafted on the Fe{sub 3}O{sub 4} nanoparticles (CDpoly-MNPs) contributed to an enhancement of adsorption capacities because of the inclusion abilities of its hydrophobic cavity with insoluble anticancer drugs through host–guest interactions. Experimental results indicated that the amounts of crosslinking agent and bonding times played a crucial role in determining morphology features of the hybrid nanocarriers. The nanocarriers exhibited a high loading efficiency (44.7 ± 1.8%) with a high saturation magnetization of 43.8 emu/g. UV–Vis spectroscopy results showed that anticancer drug 5-fluorouracil (5-Fu) could be successfully included into the cavities of the covalently linked CDpoly-MNPs. Moreover, the free carboxymethyl groups could enhance the bonding interactions between the covalently linked CDpoly-MNPs and anticancer drugs. In vitro release studies revealed that the release behaviors of CS-CDpoly-MNPs carriers were pH dependent and demonstrated a swelling and diffusion controlled release. A lower pH value led to swelling effect and electrostatic repulsion contributing to the protonation amine impact of NH{sub 3}{sup +}, and thus resulted in a higher release rate of 5-Fu. The mechanism of 5-Fu encapsulated into the magnetic chitosan nanoparticles was tentatively proposed. - Graphical abstract: A novel nanocarrier, chitosan-coated magnetic drug carrier nanoparticle (CS-CDpoly-MNPs) is fabricated for the delivery of insoluble anticancer drug by grafting CM-β-CD onto the magnetite surface. The grafting of CM-dextrins onto the surface of Fe{sub 3}O{sub 4} nanocrystal clusters can markedly increase the loading capacity of 5-Fu by virtue of CM-dextrins/5-Fu inclusion complex

  2. Replacement of cocoa butter with cocoa butter - like fat from modified palm oil in coating chocolate

    Directory of Open Access Journals (Sweden)

    Jitbunjerdkul, S.

    2007-07-01

    Full Text Available Chocolate is a confectionery product, mainly containing cocoa mass or liquor, cocoa butter (CB and sugar. Nowadays vegetable fats and modified oil are used instead of CB in chocolate products to lower the cost and to obtain the varieties of products with different characteristics and textures. Cocoa butter-like fat from modified palm oil (CBFMPO at different levels of CB replacement (60,80 and 100% were used to develop a formulation of coating chocolate. When physical and sensory properties were evaluated, the viscosity and coating ability on biscuit sticks were remarkedly decreased with increasing CBFMPO content. Hedonic mean scores of mouthfeel and coating ability of the chocolate containing 100% CBFMPO were greater than those of chocolate containing 60 and 80% CBFMPO (p<0.05. During storage of biscuit sticks dipped in the chocolate coating (chocolate containing 100% CBFMPO at room temperature (27-29oC and low temperature (20-22oC for 30 days, blooming (as shown by whiteness index occurred to a greater extent at higher temperature. At both storage temperatures, the intensity scores of glossiness and hedonic mean scores of overall liking of samples decreased but intensity scores of off-odor increased during the first 6 of days storage (p<0.05.

  3. Improving Mechanical Properties of Thermoset Biocomposites by Fiber Coating or Organic Oil Addition

    Directory of Open Access Journals (Sweden)

    Truc T. Ngo

    2015-01-01

    Full Text Available Two different thermoset biocomposite systems are experimented in this study with the hope to improve their mechanical properties. Fiberglass and hemp, in form of fabrics, are used to reinforce the thermoset polymer matrix, which includes a traditional epoxy resin and a linseed oil-based bioresin (UVL. The fiber/polymer matrix interface is modified using two different approaches: adding a plant-based oil (pine or linseed to the polymer matrix or coating the fibers with 3-(aminopropyltriethoxysilane (APTES prior to integrating them into the polymer matrix. Epoxy resin is cured using an amine-based initiator, whereas UVL resin is cured under ultraviolet light. Results show that hemp fibers with APTES prime coat used in either epoxy or UVL matrix exhibit some potential improvements in the composite’s mechanical properties including tensile strength, modulus of elasticity, and ductility. It is also found that adding oil to the epoxy matrix reinforced with fiberglass mostly improves the material’s modulus of elasticity while maintaining its tensile strength and ductility. However, adding oil to the epoxy matrix reinforced with hemp doubles the material’s ductility while slightly reducing its tensile strength and modulus of elasticity.

  4. The Effect of Reactives Diluents to the Physical Properties of Acrylated Palm Oil Based Polyurethane Coatings

    Directory of Open Access Journals (Sweden)

    Onn Munirah

    2016-01-01

    Full Text Available The development of polyurethane with hydroxyl access in a molecule leads to a new alternative of low toxicity green product. Palm oil is one of the major commodities in Malaysia. The potential of palm oil to be used as coatings raw material such as alkyd is limited due to low unsaturated side on fatty acid chains. To overcome this limitation, palm oil was modified through transesterification process to produce polyol. Acrylated isocyanate (urethane oligomer was then grafted onto polyol to produce polyurethane with vinylic ends. The polyurethane was formulated with different cross-linkers (reactive diluents and cured under UV radiation. The effect of three different diluents; monoacrylate, diacrylate and triacrylate on the properties of cured polymer were studied in this research. Fourier Transform Infrared (FTIR, Hydroxyl Value Titration, Gel Content, and Volatile Organic Compound (VOC were used for characterization. Physical testing performed were Pencil Hardness and Pull-Off Adhesion test. Novel palm oil-based polyurethane coatings have been found to have good properties with mono acrylate functionality.

  5. The Wear Characteristics of Heat Treated Manganese Phosphate Coating Applied to AlSi D2 Steel with Oil Lubricant

    Directory of Open Access Journals (Sweden)

    Venkatesan Alankaram

    2012-12-01

    Full Text Available Today, in the area of material design conversion coatings play an important role in the applications where temperature, corrosion, oxidation and wear come in to play. Wear of metals occurs when relative motion between counter-surfaces takes place, leading to physical or chemical destruction of the original top layers. In this study, the tribological behaviour of heat treated Manganese phosphate coatings on AISI D2 steel with oil lubricant was investigated. The Surface morphology of manganese phosphate coatings was examined by Scanning Electron Microscope (SEM and Energy Dispersive X-ray Spectroscopy (EDX .The wear tests were performed in a pin on disk apparatus as per ASTM G-99 Standard. The wear resistance of the coated steel was evaluated through pin on disc test using a sliding velocity of 3.0m/s under Constant loads of 40 N and 100 N with in controlled condition of temperature and humidity. The Coefficient of friction and wear rate were evaluated. Wear pattern of Manganese phosphate coated pins with oil lubricant, Heat treated Manganese phosphate coated pins with oil lubricant were captured using Scanning Electron Microscope (SEM. The results of the wear test established that the heat treated manganese phosphate coating with oil lubricant exhibited the lowest average coefficient of friction and the lowest wear loss up to 6583 m sliding distance under 40 N load and 3000 m sliding distance even under 100 N load respectively. The Wear volume and temperature rise in heat treated Manganese Phosphate coated pins with oil lubricant is lesser than the Manganese Phosphate coated pins with oil lubricant

  6. Stability assessment of injectable castor oil-based nano-sized emulsion containing cationic droplets stabilized by poloxamer-chitosan emulsifier films.

    Science.gov (United States)

    Tamilvanan, S; Kumar, B Ajith; Senthilkumar, S R; Baskar, Raj; Sekharan, T Raja

    2010-06-01

    The objectives of the present work were to prepare castor oil-based nano-sized emulsion containing cationic droplets stabilized by poloxamer-chitosan emulgator film and to assess the kinetic stability of the prepared cationic emulsion after subjecting it to thermal processing and freeze-thaw cycling. Presence of cryoprotectants (5%, w/w, sucrose +5%, w/w, sorbitol) improved the stability of emulsions to droplet aggregation during freeze-thaw cycling. After storing the emulsion at 4 degrees C, 25 degrees C, and 37 degrees C over a period of up to 6 months, no significant change was noted in mean diameter of the dispersed oil droplets. However, the emulsion stored at the highest temperature did show a progressive decrease in the pH and zeta potential values, whereas the emulsion kept at the lowest temperatures did not. This indicates that at 37 degrees C, free fatty acids were formed from the castor oil, and consequently, the liberated free fatty acids were responsible for the reduction in the emulsion pH and zeta potential values. Thus, the injectable castor oil-based nano-sized emulsion could be useful for incorporating various active pharmaceutical ingredients that are in size from small molecular drugs to large macromolecules such as oligonucleotides.

  7. Mechanically durable, superoleophobic coatings prepared by layer-by-layer technique for anti-smudge and oil-water separation

    Science.gov (United States)

    Brown, Philip S.; Bhushan, Bharat

    2015-03-01

    Superoleophobic surfaces are of interest for anti-fouling, self-cleaning, anti-smudge, low-drag, anti-fog, and oil-water separation applications. Current bioinspired surfaces are of limited use due to a lack of mechanical durability. A so-called layer-by-layer approach, involving charged species with electrostatic interactions between layers, can provide the flexibility needed to improve adhesion to the substrate while providing a low surface tension coating at the air interface. In this work, a polyelectrolyte binder, SiO2 nanoparticles, and a fluorosurfactant are spray deposited separately to create a durable, superoleophobic coating. Polydiallyldimethylammonium chloride (PDDA) polyelectrolyte was complexed with a fluorosurfactant layer (FL), which provides oil repellency while being hydrophilic. This oleophobic/superhydrophilic behavior was enhanced through the use of roughening with SiO2 particles resulting in a superoleophobic coating with hexadecane contact angles exceeding 155° and tilt angles of less than 4°. The coating is also superhydrophilic, which is desirable for oil-water separation applications. The durability of these coatings was examined through the use of micro- and macrowear experiments. These coatings currently display characteristics of transparency. Fabrication of these coatings via the layer-by-layer technique results in superoleophobic surfaces displaying improved durability compared to existing work where either the durability or the oil-repellency is compromised.

  8. Mechanically durable, superoleophobic coatings prepared by layer-by-layer technique for anti-smudge and oil-water separation

    Science.gov (United States)

    Brown, Philip S.; Bhushan, Bharat

    2015-01-01

    Superoleophobic surfaces are of interest for anti-fouling, self-cleaning, anti-smudge, low-drag, anti-fog, and oil-water separation applications. Current bioinspired surfaces are of limited use due to a lack of mechanical durability. A so-called layer-by-layer approach, involving charged species with electrostatic interactions between layers, can provide the flexibility needed to improve adhesion to the substrate while providing a low surface tension coating at the air interface. In this work, a polyelectrolyte binder, SiO2 nanoparticles, and a fluorosurfactant are spray deposited separately to create a durable, superoleophobic coating. Polydiallyldimethylammonium chloride (PDDA) polyelectrolyte was complexed with a fluorosurfactant layer (FL), which provides oil repellency while being hydrophilic. This oleophobic/superhydrophilic behavior was enhanced through the use of roughening with SiO2 particles resulting in a superoleophobic coating with hexadecane contact angles exceeding 155° and tilt angles of less than 4°. The coating is also superhydrophilic, which is desirable for oil-water separation applications. The durability of these coatings was examined through the use of micro- and macrowear experiments. These coatings currently display characteristics of transparency. Fabrication of these coatings via the layer-by-layer technique results in superoleophobic surfaces displaying improved durability compared to existing work where either the durability or the oil-repellency is compromised. PMID:25731716

  9. Effects of Chitosan Coating on Factors Relating to Enzymatic Browning of Fresh-Cut Lotus Root Slices%壳聚糖对鲜切莲藕酶促褐变相关因子的影响

    Institute of Scientific and Technical Information of China (English)

    汪伟; 张伟; 孙莹; 高成; 朱丽琴

    2014-01-01

    The effects of chitosan coating of fresh-cut lotus root slices on the quality and relating factors in enzymatic browning were studied to explore the mechanism of chitosan in inhibition of enzymatic browning of fresh-cut lotus roots.Fresh-cut lotus root slices were coated with chitosan in different concentrations ( 1%, 2%) and then stored at 4℃.The results showed that chitosan treatment significantly inhibited the increase of browning degree and weight loss rate, and maintained higher vitamin C and total phenolic content.Chitosan coating significantly inhibited the production of superoxide free radicals ( O2 · -) and H2 O2 content,maintained high catalase activity,and significantly inhibited the activity of polyphenol oxidase and peroixdase during stor-age.Treatment with 2%chitosan showed better effect.%为探讨壳聚糖对鲜切莲藕的酶促褐变抑制机理,在4℃下对鲜切莲藕进行壳聚糖涂膜保鲜试验,研究了不同质量分数(1%、2%)壳聚糖对鲜切莲藕品质的影响和酶促褐变相关因子的影响。结果表明:壳聚糖处理显著抑制了鲜切莲藕贮藏过程中的褐变和水分损失,保持较高的维生素C和总酚含量,显著抑制了超氧阴离子(O2·-)和过氧化氢(H2O2)的积累,保持较高的过氧化氢酶(CAT)活性,并显著抑制了多酚氧化酶(PPO)和过氧化物酶(POD)活性。且2%的壳聚糖处理效果更好。

  10. New backing layer for transdermal drug delivery systems: coatings based on fatty acid and beeswax on chitosan films

    OpenAIRE

    Rullier-Birat, Bénédicte; Cazalbou, Sophie; Nassar, Maria Alejandra; Sandrine, Cavalie; Tourrette, Audrey

    2015-01-01

    International audience; Fatty acids and beeswax are known to improve barrier properties of biodegradable materials. Thanks to their hydrophobic character, they can act as a barrier against water giving to the material more occlusive properties. This work was aimed at preparing fatty acid and beeswax coatings for a transdermal drug delivery system. In order to study occlusive properties of these coatings, water vapor permeability and contact angle measurements were carried out. The most homoge...

  11. Water and oil repellency of flexible silica-coated polymeric substrates

    Science.gov (United States)

    Hsieh, Chien-Te; Cheng, Yu-Shun; Hsu, Shu-Min; Lin, Jia-Yi

    2010-06-01

    A facile coating technique was used for the one-step creation of silica-sphere layers onto flexible polypropylene (PP) substrates, which showed the enhanced repellency toward liquid droplets with different surface tensions, ranging from 25.6 to 72.3 mN/m. One-step solution preparation comprised the homogenous mixing of colloidal silica nanospheres and perfluoroalkyl methacrylic copolymer, and the resulting F-silica slurry was subsequently deposited over the PP films, which showed good adhesion. The flexible silica-coated polymeric film displayed a remarkable repellency toward water and oil drops, when compared with the F-coated PP flat film. The silica-stacking layers on the PP substrate generated a roughened surface, owing to the creation of bionic surface hierarchically combined with multiple-scale architecture. To clarify this, the wetted fraction was determined from Cassie-Baxter equation, and the work of adhesion, based on Young-Duprè equation, was used to examine the sliding ability of the resulting polymeric films. The cross-cut test incorporated with film bending proved the excellent adherence between silica layer and PP substrate. A satisfactory durability in water and oil immersions for 10 days showed that the resulting PP film possesses strong adhesion and better repellency for a long period, confirming a promising commercial feasibility.

  12. Quality enhancement in the Japanese sea bass (Lateolabrax japonicas) fillets stored at 4°C by chitosan coating incorporated with citric acid or licorice extract.

    Science.gov (United States)

    Qiu, Xujian; Chen, Shengjun; Liu, Guangming; Yang, Qiuming

    2014-11-01

    The preserving effects of chitosan, chitosan and citric acid, chitosan and licorice extract on fresh Japanese sea bass fillets stored at 4 °C for 12 days were studied. Results showed that citric acid or licorice extract can enhance the preserving function of chitosan significantly by retarding lipid oxidation and inhibiting microbial growth as reflected in thiobarbituric acid reactive substances and total plate count, respectively. Both total volatile basic nitrogen values and sensory scores indicated chitosan and citric acid or licorice extract can significantly reduce the quality loss and extend the shelf life of Japanese sea bass fish fillets during refrigerated storage. Citric acid or licorice extract with chitosan could thus be applied in the seafood industry to enhance quality of fish fillets as natural preservatives.

  13. Effect of chitosan-carvacrol edible coatings on the quality and shelf life of tilapia (Oreochromis niloticus fillets stored in ice

    Directory of Open Access Journals (Sweden)

    Saraí CHAPARRO-HERNÁNDEZ

    2015-01-01

    Full Text Available Abstract Fish consumption has increased in recent years. However, fish meat is highly perishable, which demonstrates the need for technologies to preserve its quality. Edible coatings (EC might provide an alternative to extend the shelf life of fish. The goal of this study was to evaluate the effect of EC of chitosan (C in combination with carvacrol (CAR on the physical and microbiological changes of tilapia fillets. Fillets were submerged for two minutes in different treatments (T1: control; T2: C 2%; T3: C 2% + 0.125% CAR; T 4: C 2% + 0.25% CAR. At the end of storage, T1 and T2 showed the lowest values of total volatile bases (TVB. The color parameters L*, a* and b* varied from each treatment. The texture decreased and the different treatments reduced the microbial population in relation to the control; T3 and T4 were the most effective. These results show that the use of C with CAR might be an alternative method to preserve the quality and safety of tilapia fillets.

  14. Competitive Fixed-Bed Adsorption of Pb(II, Cu(II, and Ni(II from Aqueous Solution Using Chitosan-Coated Bentonite

    Directory of Open Access Journals (Sweden)

    Wan-Chi Tsai

    2016-01-01

    Full Text Available Fixed-bed adsorption studies using chitosan-coated bentonite (CCB as adsorbent media were investigated for the simultaneous adsorption of Pb(II, Cu(II, and Ni(II from a multimetal system. The effects of operational parameters such as bed height, flow rate, and initial concentration on the length of mass transfer zone, breakthrough time, exhaustion time, and adsorption capacity at breakthrough were evaluated. With increasing bed height and decreasing flow rate and initial concentration, the breakthrough and exhaustion time were observed to favorably increase. Moreover, the adsorption capacity at breakthrough was observed to increase with decreasing initial concentration and flow rate and increasing bed height. The maximum adsorption capacity at breakthrough of 13.49 mg/g for Pb(II, 12.14 mg/g for Cu(II, and 10.29 mg/g for Ni(II was attained at an initial influent concentration of 200 mg/L, bed height of 2.0 cm, and flow rate of 0.4 mL/min. Adsorption data were fitted with Adams-Bohart, Thomas, and Yoon-Nelson models. Experimental breakthrough curves were observed to be in good agreement (R2>0.85 and E%<50% with the predicted curves generated by the kinetic models. This study demonstrates the effectiveness of CCB in the removal of Pb(II, Cu(II, and Ni(II from a ternary metal solution.

  15. Bifunctional coating based on carboxymethyl chitosan with stable conjugated alkaline phosphatase for inhibiting bacterial adhesion and promoting osteogenic differentiation on titanium

    Science.gov (United States)

    Zheng, Dong; Neoh, Koon Gee; Kang, En-Tang

    2016-01-01

    In this work, alkaline phosphatase (ALP) was covalently immobilized on carboxymethyl chitosan (CMCS)-coated polydopamine (PDA)-functionalized Ti to achieve a bifunctional surface. Our results showed ∼89% reduction in Staphylococcus epidermidis adhesion on this surface compared to that on pristine Ti. The ALP-modified Ti supported cell proliferation, and significantly enhanced cellular ALP activity and calcium deposition of osteoblasts, human mesenchymal stem cells (hMSCs) and human adipose-derived stem cells (hADSCs). The extent of enhancement in the functions of these cells is dependent on the surface density of immobilized ALP. The substrate prepared using an ALP solution of 50 μg/cm2 resulted in 44%, 54% and 129% increase in calcium deposited by osteoblasts, hMSCs and hADSCs, respectively, compared to those cultured on pristine Ti. The ALP-modified substrates also promoted the osteogenic differentiation of hMSCs and hADSCs by up-regulating gene expressions of runt-related transcription factor 2 (RUNX2), osterix (OSX), and osteocalcin (OC) in the two types of stem cells. The surface-immobilized ALP was stable after being subjected to 1 h immersion in 70% ethanol and autoclaving at 121 °C for 20 min. However, the enzymatic bioactivity of the surface-immobilized ALP was reduced by about 50% after these substrates were immersed in phosphate buffered saline (PBS) or PBS containing lysozyme for 14 days.

  16. Preparation and characterization of chitosan-Polyethylene glycol-polyvinylpyrrolidone-coated superparamagnetic iron oxide nanoparticles as carrier system: Drug loading and in vitro drug release study.

    Science.gov (United States)

    Prabha, G; Raj, V

    2016-05-01

    In the present research work, the anticancer drug "curcumin" is loaded with Chitosan (CS)-polyethylene glycol (PEG)-polyvinylpyrrolidone (PVP) (CS-PEG-PVP) polymer nanocomposites coated with superparamagnetic iron oxide (Fe3 O4 ) nanoparticles. The system can be used for targeted and controlled drug delivery of anticancer drugs with reduced side effects and greater efficiency. The prepared nanoparticles were characterized by Fourier transmission infrared spectroscopy (FTIR), vibrating sample magnetometry (VSM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Curcumin drug-loaded Fe3 O4 -CS, Fe3 O4 -CS- PEG and Fe3 O4 -CS-PEG-PVP nanoparticles exhibited the mean particle size in the range of 183 - 390 nm with a zeta potential value of 26 mV-41 mV as measured using Malvern Zetasizer. The encapsulation efficiency, loading capacity and in-vitro drug release behaviour of curcumin drug-loaded Fe3 O4 -CS, Fe3 O4 -CS-PEG, and Fe3 O4 -CS-PEG-PVP nanoparticles were studied using UV spectrophotometer. Besides, the cytotoxicity of the prepared nanoparticles using MTT assay was also studied. The curcumin drug release was examined at different pH medium (4.5 and 7.4) and temperature (37°C and 45°C), and it was proved that the drug release depends upon the pH medium and temperature in addition to the nature of matrix.

  17. Improving the encapsulation efficiency and sustained release behaviour of chitosan/β-lactoglobulin double-coated microparticles by palmitic acid grafting.

    Science.gov (United States)

    Yang, Han-Joo; Lee, Pei Sia; Choe, Jaehyeog; Suh, Seokjin; Ko, Sanghoon

    2017-04-01

    Chitosan (CS) was grafted with 0.1 and 0.5% (w/v) palmitic acid (PA) to improve its encapsulation efficiency (EE) and sustained release characteristics when forming CS microparticles. Thereafter, PA-grafted CS (PA-CS) microparticles were coated with denatured β-lactoglobulin (βlg), which forms an outer protective layer. The possibility of hydrophobic interaction with the hydrophobic substances in the CS microparticles increased as the proportion of the grafted PA increased. EE was measured as 64.79, 83.72, and 85.00% for the non-grafted, 0.1, and 0.5% PA-CS microparticles, respectively. In simulated small intestinal conditions, 4.66 and 17.55% of the core material release in the PA-CS microparticles were sustained after 180min by 0.1, and 0.5% PA grafting, respectively. PA grafting enables the sustained release in simulated gastrointestinal fluids by enhancing the hydrophobic interaction between CS and the hydrophobic core material.

  18. Optimization of process parameters for removal of heavy metals by biomass of Cu and Co-doped alginate-coated chitosan nanoparticles.

    Science.gov (United States)

    Esmaeili, Akbar; Khoshnevisan, Najmeh

    2016-10-01

    In this study, the efficiency of alginate-coated chitosan nanoparticles (Alg-CS-NPs) for removal of heavy metals from industrial effluents was investigated. To this end, the researchers constructed a reactor containing biomass, using response surface methodology (RSM) for process optimization. Reactor tests were carried out with both synthetic and industrial effluents containing nickel. The optimum conditions to achieve maximum removal efficiency (RE) rates for both synthetic and industrial effluents were specified for contact time (0-120min), pH level (1-9), biomass dose (0.1-0.9g), and initial metal ion concentration (10-90mg/L). It was determined that 94.48% of the nickel could be removed at pH=3, 70mg/L initial nickel concentration, a dose of 0.3g biomass, and 30min contact time. The kinetic data fit well to a pseudo second-order model and the equilibrium data of the metal ions could be described well with Freundlich isotherm models.

  19. Construction of a sensitive and selective sensor for morphine using chitosan coated Fe{sub 3}O{sub 4} magnetic nanoparticle as a modifier

    Energy Technology Data Exchange (ETDEWEB)

    Dehdashtian, Sara [Department of Chemistry, Behbahan Khatam Al-Anbia University of Technology, Behbahan (Iran, Islamic Republic of); Gholivand, Mohammad Bagher, E-mail: mbgholivand@yahoo.com [Department of Analytical Chemistry, Faculty of Chemistry, Razi University, Kermanshah (Iran, Islamic Republic of); Shamsipur, Mojtaba; Kariminia, Samira [Department of Analytical Chemistry, Faculty of Chemistry, Razi University, Kermanshah (Iran, Islamic Republic of)

    2016-01-01

    A simple and sensitive sensor based on carbon paste electrode (CPE) modified by chitosan-coated magnetic nanoparticle (CMNP) was developed for the electrochemical determination of morphine (MO). The proposed sensor was characterized with scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). The electrooxidation of MO was studied on modified carbon paste electrode using cyclic voltammetry, chronoamperometry and differential pulse voltammetry as diagnostic techniques. The oxidation peak potential of morphine on the CMNP/CPE appeared at 380 mV which was accompanied with smaller overpotential and increase in oxidation peak current compared to that obtained on the bare carbon paste electrode (CPE). Under optimum conditions the sensor provides two linear DPV responses in the range of 10–2000 nM and 2–720 μM for MO with a detection limit of 3 nM. The proposed sensor was successfully applied for monitoring of MO in serum and urine samples and satisfactory results were obtained. - Highlights: • A sensitive and selective voltammetric sensor for MO by using a carbon paste electrode modified with CMNP was introduced. • CMNP as a new modifier facilitates the charge transfer of MO oxidation process. • The proposed sensor was used successfully for MO determination in biological fluids such as serum and urine samples. • This sensor is fabricated easily and has good stability and high sensitivity.

  20. Vegetable oil based eco-friendly coating materials: A review article

    Directory of Open Access Journals (Sweden)

    Manawwer Alam

    2014-09-01

    Full Text Available Vegetable oils (VO constitute the single, largest, easily available, low cost, non-toxic, non-depletable, biodegradable family yielding materials that are capable of competing with fossil fuel derived petro-based products. The outstanding feature of VO is their unique chemical structure with to unsaturation sites, epoxies, hydroxyls, esters and other functional groups along with inherent fluidity characteristics. These enable them to undergo various chemical transformations producing low molecular weight polymeric materials with versatile applications, particularly as chief ingredients in paints and coatings. In this manuscript, we have briefly described important VO derived materials such as alkyds, polyesteramides, polyetheramides, polyurethanes, epoxies, polyols, along with their preparation and applications as protective coatings. A small portion of the review is also dedicated to the future perspectives in the field. Inspite of their extensive utilization in the world of coatings, literature survey revealed that in the past (from 1990s to date no review has come up describing the chemistry and applications of VO polymer based coating materials.

  1. Obtention, characterization and in vitro evaluation of polycaprolactone-chitosan coatings growth on chemically treated Ti6Al4V alloy; Obtencion, caracterizacion y evaluacion in vitro de recubrimientos de policaprolactona-quitosano sobre la aleacion Ti6Al4V tratada quimicamente

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Rodriguez, L. S.; Quintero Jaime, A. F.; Pena Ballesteros, D. Y.; Estupinan Duran, H. A.

    2014-07-01

    Polymeric coatings were obtained polycaprolactone-chitosan. The coatings were applied by dip-coating technique, on Ti6Al4V substrates chemically treated with NaOH solution. Based on SEM morphological analysis and infrared spectra, it was observed that the amount of polycaprolactone in the coating obtained had an effect in retaining the chitosan on the surface, associated with the emission of R-OH bond and the morphological characteristics. Impedance spectra performed on the polymeric films showed phenomena related processes adsorption of ionic species to monolayer formation on the surface. These spectra showed equally charge transfer phenomena generated by the morphological characteristics of the coatings, such as its porosity, density and homogeneity. The coated substrate was immersing in SBF solution for 8 days, allowed to observe its adsorption capacity of calcium through nucleation and precipitation of calcium phosphates, bioactive character displaying a front medium. (Author)

  2. Edible coatings enriched with essential oils and their compounds for fresh and fresh-cut fruit.

    Science.gov (United States)

    Antunes, Maria D; Gago, Custodia M; Cavaco, Ana M; Miguel, Maria G

    2012-08-01

    Fresh fruit and vegetables consumption has increased in the past few years due to the enhanced awareness of consumers for healthy food. However, these products are highly perishable, and losses can be of great significance if postharvest correct management is not provided. Fresh-cut products are of increasing importance, since they are presented to the consumer in a state that allows for direct and immediate consumption. However, those products are even more perishable since cutting can induce a series of senescence associated responses to wounding, and are more susceptible to microbial spoilage. Edible coatings, which intend to reduce ripening processes and protect the fruit from water loss and spoilage may be a good way to enhance the shelf life of these products. More recently, the inclusion of additives into these edible coatings to increase their effectiveness, such as essential oils and their constituents with antimicrobial and antioxidant activities, has been reported and patented.

  3. PHYSIOLOGICAL STATUS, BLOOD PROFILE AND BODY COMPOSITION OF SHEEP FED WITH CA-SAPONIFIED LEMURU OIL COATED BY HERBS

    Directory of Open Access Journals (Sweden)

    Dewi Apri Astuti

    2015-06-01

    Full Text Available This study was aimed to evaluate the physiological status, blood profiles and body composition of sheep fed with Ca-saponified lemuru oil coated by herbs. Twenty fat-tailed sheep (av. BW 23±1.2 kg were used in this experiment by using Completely Randomized Design with five treatments ration and four replications of each. Sheep fed with concentrate containing 3% Ca-saponified lemuru oil and king grass (1:1 ad libitum. Treatments were control diet without herbs (R1; Ca-saponified lemuru oil coated by curcumae domestica (R2; coated by Zingiber officinale Rosc (R3; coated by Eugenia polyantha (R4 and coated by Pluchea indica Less (R5. Data of physiological parameters were measured three times a day, in the morning, at noon and afternoon. Blood samples were collected at the end of the experiment through jugular vein, together with zero sample for Urea Space measurement. The variables observed were physiological data (heart rate, respiration rate, and rectal temperature, blood profiles (erythrocyte, hemoglobin, packed cell volume (PCV, leucocytes and body composition (water, protein and fat measured using Urea Space technique. Results of the study showed that sheep fed with Ca-saponified lemuru oil coated by herbs was not significantly different on heart rate, respiration rate and rectal temperature among treatments. Meanwhile, total leucocytes, neutrophil cell, and lymphocytes significantly increased (P<0.05 by the treatment. Body composition percentage (water, protein and fat were same in all treatments, except the total body fat and energy retained. In conclusion, supplementation of 3% Ca-saponified lemuru oil coated by Curcumae domestica, Zingiber officinale Rosc, Eugenia polyantha and Pluchea indica Less in fat-tailed sheep had no effect on physiological parameters, but improved the leucocyte and neutrophil cells. Total body fat and energy retained lower compared to control treatment. (Key words: Body composition, Ca-saponified, Herbs, Lemuru

  4. Chitosan magnetic nanoparticles for drug delivery systems.

    Science.gov (United States)

    Assa, Farnaz; Jafarizadeh-Malmiri, Hoda; Ajamein, Hossein; Vaghari, Hamideh; Anarjan, Navideh; Ahmadi, Omid; Berenjian, Aydin

    2016-06-01

    The potential of magnetic nanoparticles (MNPs) in drug delivery systems (DDSs) is mainly related to its magnetic core and surface coating. These coatings can eliminate or minimize their aggregation under physiological conditions. Also, they can provide functional groups for bioconjugation to anticancer drugs and/or targeted ligands. Chitosan, as a derivative of chitin, is an attractive natural biopolymer from renewable resources with the presence of reactive amino and hydroxyl functional groups in its structure. Chitosan nanoparticles (NPs), due to their huge surface to volume ratio as compared to the chitosan in its bulk form, have outstanding physico-chemical, antimicrobial and biological properties. These unique properties make chitosan NPs a promising biopolymer for the application of DDSs. In this review, the current state and challenges for the application magnetic chitosan NPs in drug delivery systems were investigated. The present review also revisits the limitations and commercial impediments to provide insight for future works.

  5. Surface Coating Studies of Polyurethane Derived from [(Alkyd-(Epoxy Resin Treated Castor Oil] Using Isophorene Diisocynate - II

    Directory of Open Access Journals (Sweden)

    Dinesh. P. Patel

    2012-07-01

    Full Text Available Castor oil (C was reacted with profitable epoxy resin (E (diglycidylether of bisphenol-A, DGEBF at a range of mole ratios. The consequential products (Castor oil- Epoxy resin were nominated as CEs. Isocyanate terminated castor oil Polyurethane (ICOPU was prepared by reaction of castor oil and various proportion of Isophoren diisocyanate. A commercial alkyd resin was blended with various proportions of CEs and ICOPU. A unique solvent system, which shows a one – phase clear solution and a clear coat of binder system, was used. All the blends were applied on mild steel panels and characterized for drying time, adhesion, flexibility, hardness, impact resistance and chemical resistance properties.

  6. Synthesizing of oil palm empty fruit bunch lignin derivatives and potential use for production of linerboard coating

    Directory of Open Access Journals (Sweden)

    Danupong Narapakdeesakul

    2013-12-01

    Full Text Available This work describes the synthesis of oil palm empty fruit bunch (OPEFB lignin derivatives and their performance for the production of linerboard coating. OPEFB lignin derivatives were synthesized by the reactions of OPEFB lignin and soy bean oil with two proportions (OPEFB lignin: soy bean oil at 1:1 and 1:2. The formation of the derivatives was confirmed by FTIR analysis. OPEFB lignin derivative-based coatings were produced by mixing of oxidized starch solution and 5% lignin derivatives with the addition of 1% arabic gum (w/w of the derivatives as the stabilizer. It was found that the OPEFB lignin derivative-based coatings had low viscosity similar to commercial wax. OPEFB lignin derivative-coated linerboards had a better (p0.05. The mechanical properties, including ring crush, tensile and bursting strength of linerboards coated with OPEFB lignin derivatives and commercial wax were not different (p>0.05. The results point out that the OPEFB lignin derivatives had a performance suitable for use as linerboard coating. It provided a better water resistance of the coated linerboards, and was also more environmental friendly.

  7. The Tribological Properties of the Hot-extrusion Nylon Coating in the Oil Well Environment

    Institute of Scientific and Technical Information of China (English)

    MO Yi-min; PAN Yun-ping; WANG Xiu-mei

    2003-01-01

    The friction and wear properties of the nylon coating, prepared by hot-extrusion, used to protect the surface of the flexible continuous sucker rod were studied by using a pin-on-disc wear tester in the simulated oil well environment. The effects of sliding speed and load were considered. The wear mechanism was also studied by using a scanning electron microscope ( SEM ). The result shows that the friction coefficients of both kinds of materials, JKPA and ZZ7024B, used to protect the surface of the flexible continuous sucker rod decrease with sliding speed increase , but change little with load increase in the simulated oil well environment . The value of friction coefficient of ZZ7024 B is smaller than that of JKPA. The minimum value of friction coefficient of ZZ7024 B is about 0.05. The wear volume of ZZ7024 B is smaller than that of JKPA under the same conditions of experimentation.

  8. Modeling the changes in the concentration of aromatic hydrocarbons from an oil-coated gravel column

    Science.gov (United States)

    Jung, Jee-Hyun; Kang, Hyun-Joong; Kim, Moonkoo; Yim, Un Hyuk; An, Joon Geon; Shim, Won Joon; Kwon, Jung-Hwan

    2015-12-01

    The performance of a lab-scale flow-through exposure system designed for the evaluation of ecotoxicity due to oil spills was evaluated. The system simulates a spill event using an oil-coated gravel column through which filtered seawater is passed and flows into an aquarium containing fish embryos of olive flounder ( Paralichthys olivaceus) and spotted sea bass ( Lateolabrax maculates). The dissolved concentrations of individual polycyclic aromatic hydrocarbons (PAHs) in the column effluent were monitored and compared with theoretical solubilities predicted by Raoult's law. The effluent concentrations after 24 and 48 h were close to the theoretical predictions for the higher molecular weight PAHs, whereas the measured values for the lower molecular weight PAHs were lower than predicted. The ratios of the concentration of PAHs in flounder embryos to that in seawater were close to the lipid-water partition coefficients for the less hydrophobic PAHs, showing that equilibrium was attained between embryos and water. On the other hand, 48 h were insufficient to attain phase equilibrium for the more hydrophobic PAHs, indicating that the concentration in fish embryos may be lower than expected by equilibrium assumption. The results indicate that the equilibrium approach may be suitable for less hydrophobic PAHs, whereas it might overestimate the effects of more hydrophobic PAHs after oil spills because phase equilibrium in an oil-seawater-biota system is unlikely to be achieved. The ecotoxicological endpoints that were affected within a few days are likely to be influenced mainly by moderately hydrophobic components such as 3-ring PAHs.

  9. Pharmacokinetics, tissue distribution, and metabolites of a polyvinylpyrrolidone-coated norcantharidin chitosan nanoparticle formulation in rats and mice, using LC-MS/MS

    Directory of Open Access Journals (Sweden)

    Ding XY

    2012-04-01

    Full Text Available Xin-Yuan Ding1, Cheng-Jiao Hong2, Yang Liu1, Zong-Lin Gu1, Kong-Lang Xing1, Ai-Jun Zhu1, Wei-Liang Chen1, Lin-Seng Shi1, Xue-Nong Zhang1, Qiang Zhang31Department of Pharmaceutics, College of Pharmaceutical science, Soochow University, Suzhou, 2Jiang Su Provincial Key Laboratory of Radiation Medicine and Protection, Suzhou, 3Department of Pharmaceutics, School of Pharmaceutical Science, Peking University, Beijing, People’s Republic of ChinaAbstract: A novel formulation containing polyvinylpyrrolidone (PVP K30-coated norcantharidin (NCTD chitosan nanoparticles (PVP–NCTD–NPs was prepared by ionic gelation between chitosan and sodium tripolyphosphate. The average particle size of the PVP–NCTD–NPs produced was 140.03 ± 6.23 nm; entrapment efficiency was 56.33% ± 1.41%; and drug-loading efficiency was 8.38% ± 0.56%. The surface morphology of NCTD nanoparticles (NPs coated with PVP K30 was characterized using various analytical techniques, including X-ray diffraction and atomic force microscopy. NCTD and its metabolites were analyzed using a sensitive and specific liquid chromatography-tandem mass spectrometry method with samples from mice and rats. The results indicated the importance of the PVP coating in controlling the shape and improving the entrapment efficiency of the NPs. Pharmacokinetic profiles of the NCTD group and PVP–NCTD–NP group, after oral and intravenous administration in rats, revealed that relative bioavailabilities were 173.3% and 325.5%, respectively. The elimination half-life increased, and there was an obvious decrease in clearance. The tissue distribution of NCTD in mice after the intravenous administration of both formulations was investigated. The drug was not quantifiable at 6 hours in all tissues except for the liver and kidneys. The distribution of the drug in the liver and bile was notably improved in the PVP–NCTD–NP group. The metabolites and excretion properties of NCTD were investigated by analyzing

  10. An Improved Chitosan Coating Method for Bacteriostasis and Preservation of Grass Carp During Refrigerated Storage%改良壳聚糖涂膜技术对草鱼肉抑菌保鲜效果的研究

    Institute of Scientific and Technical Information of China (English)

    王发祥; 王满生; 刘永乐; 俞健; 王建辉; 李向红

    2013-01-01

    Chitosan coating is a new preservation technology with good preservation effect and superiority,but has some disadvantages,such as slow speed of film forming,difficulty in the operating and controlling the film thickness.Thus,improving the composition of coating solution and the coating technology is important for its preservation effect.The improved preservative and antibacterial effects on refrigerated grass carp meat was investigated by using new coating method with adding volatile ethanol.By varying the concentrations of ethanol and chitosan in coating solution,as well as coating methods,the total bacteria colony and TVB-N of the fish during its cold storage were studied.The results showed that the coating solution containing 75% ethanol had better antimicrobial and bactericidal effects with a decrease of>51% in initial bacterial count of fresh fish meat.The best chitosan concentration was 1.0% comprehensively considering its film-forming ability and antibacterial effect.In addition,the coating methods showed little difference in affecting the preservation of Grass carp,while spray coating pattern was relatively convenient in operation and economical in coating solution.These findings demonstrated that spray coating using acidic chitosan solution containing 75% ethanol was an effectvely new fish preservation technology.%壳聚糖溶液涂膜是一种新兴的保鲜技术,具有较好的保鲜效果和优越性,但尚存在成膜较慢、不易操作、膜层厚度难控制等缺点,因而改善涂膜液的组成和涂膜技术是涂膜保鲜的关键.本文研究了新的涂膜方式和添加易挥发的乙醇来改进壳聚糖涂膜液的成膜和抑菌效果.通过改变不同乙醇浓度、壳聚糖浓度和涂膜方式等条件,分析其对冷藏过程中草鱼肉的微生物菌落总数和TVB-N值的影响.结果表明,涂膜溶液中含有75%的乙醇时,不仅对冷藏草鱼肉的抑菌效果好,而且还具有减菌作用,使样品初始微

  11. Fabrication of polydopamine-coated superhydrophobic fabrics for oil/water separation and self-cleaning

    Science.gov (United States)

    Xu, Zhanglian; Miyazaki, Koji; Hori, Teruo

    2016-05-01

    We report a fabric coating method inspired the superhydrophobic properties of lotus leaves and the strong adhesion of the adhesive proteins in mussels. Dopamine, which mimics the single units of the adhesive mussel proteins, was polymerized in an alkaline aqueous solution to coat the surface of fabrics. The versatile reactivity of polydopamine allows subsequent Ag deposition to form a lotus-leaf-like rough structure on the fabric surface. The composite fabric exhibited high water repellence after fluorination. Because dopamine can adhere to all kinds of materials, this method can be applied to many fabrics regardless of their properties and chemical compositions using a universal process. The modified fabrics exhibited excellent anti-wetting and self-cleaning properties with contact angles of >150° and sliding angles lower than 9°. The fabrics also efficiently separated oil from oil/water mixtures under various conditions. Our method is versatile and simple compared with other hydrophobic treatment methods, which usually only work on one type of fabric.

  12. Sensory and chemical stability in coated peanuts with the addition of essential oils and synthetic antioxidants

    Directory of Open Access Journals (Sweden)

    Olmedo, R. H.

    2012-03-01

    Full Text Available The objective of this work was to evaluate the antioxidant effect of essential oils on the oxidative stability of coated peanuts. Untreated coated peanuts (CP and treated coated peanuts with the addition of rosemary (CP-R, oregano (CP-O and laurel (CP-L essential oils and BHT (CPBHT were prepared. Peroxide values (PV and p-anisidine values (AV and the intensity ratings of sensory attributes by descriptive analysis were measured during 112 days of storage at room temperature (23°C. CP-BHT exhibited the lowest PV and AV increase. CP-R, CP-O and CP-L showed lower rates of increase in PV and AV than CP. The oxidized and cardboard flavor intensity ratings increased much more in CP during storage than the other studied products. CPBHT also showed the lowest increase in the intensity ratings of these sensory attributes. Three essential oils, namely, laurel, oregano and rosemary showed antioxidant activity and increased the shelf life of coated peanuts.

    El objetivo de este trabajo fue evaluar el efecto antioxidante de aceites esenciales sobre la estabilidad oxidativa en maní recubiertos. Se prepararon maníes recubiertos sin agregados (CP, y con el agregado de aceites esenciales de romero (CP-R, orégano (CP-O y laurel (CP-L y BHT (CPBHT. Se midieron, durante 112 días de almacenamiento, los valores de peróxidos (PV y p-anisidina (AV, y las intensidades de atributos sensoriales mediante análisis descriptivo. CP-BHT presentó el menor valor de PV y AV. CP-R, CP-O y CP-L tuvieron mayor PV y AV respecto a CP. Los valores de intensidad del sabor oxidado y cartón tuvieron un mayor incremento en CP durante el almacenamiento con respecto a los otros productos estudiados. La muestra CP-BHT también mostró los menores valores de intensidad de estos atributos sensoriales. Los aceites esenciales de laurel, orégano y romero presentaron actividad antioxidante e incrementaron la vida útil del maní recubierto.

  13. Effect of Nano-chitosan Coating on Quality of Fresh-cut Zizania latifolia%纳米壳聚糖涂膜对鲜切茭白品质的影响

    Institute of Scientific and Technical Information of China (English)

    周静峰; 罗海波; 王隽; 江凯; 郁志芳

    2013-01-01

    研究了纳米壳聚糖涂膜对鲜切茭白品质的影响.鲜切茭白分别在去离子水(对照)、10g/L壳聚糖或10g/L壳聚糖+1.5 g/L纳米壳聚糖溶液中浸泡3min,自然晾干包装后于1±0.5℃下贮藏12d.贮藏过程中每3d测定鲜切茭白的白色指数(WI)、硬度、失重率及木质素、还原糖、抗坏血酸含量,PAL、SOD、CAT和POD活力.结果显示,纳米壳聚糖涂膜显著抑制了鲜切茭白WI值的下降和木质素含量的增加,维持了相对高的硬度及还原糖和抗坏血酸含量;贮藏12d后失重率为1.12%; PAL和POD活性显著低于对照(P<0.05),SOD和CAT活性显著高于对照(P<0.05).以上结果表明,纳米壳聚糖涂膜能有效延缓鲜切茭白褐变和木质化,提高抗氧化酶类活性,提示纳米壳聚糖涂膜具有商业上控制鲜切茭白品质劣变的潜在价值.%The effect of nano-chitosan coating on the quality of fresh-cut Z.latifolia was investigated.Fresh-cut Z.latifolia slices were dipped into deionised water (the control),10 g/L chitosan or the mixture of 10 g/L chitosan and 1.5 g/L nano-chitosan for 3 min,and then dried,packaged and finally stored for 12 days at 1±0.5 ℃.Changes in whiteness index (WI),firmness,weight loss,lignin,reducing sugar and ascorbic acid contents,phenylalanine ammonia-lyase (PAL),superoxide dismutase (SOD),eatalase (CAT) and peroxidase (POD) activities were evaluated at intervals of two days.The results showed that the nano-chitosan coating significantly inhibited the decline of WI value and the increase of lignin content,maintained relatively high firmness,reducing sugars and ascorbic acid contents of fresh-cut Z.latifolia.After a 12-day storage at 1±0.5 ℃,the weight loss of the fresh-cut Z.latifolia slices was 1.12%.The treatment also inhibited the activities of PAL and POD but promoted SOD and CAT activities compared with the control.The present findings indicated that the nano-chitosan coating could inhibit browning and

  14. Effect of cassava starch-based edible coating incorporated with lemongrass essential oil on the quality of papaya MJ9

    Science.gov (United States)

    Praseptiangga, D.; Utami, R.; Khasanah, L. U.; Evirananda, I. P.; Kawiji

    2017-02-01

    Edible films and coatings have emerged as an alternative packaging in food applications and have received much attention due to their advantages. The incorporation of essential oils in film matrices to give antimicrobial properties had been observed recently, and could be used as promising preservation technology. In this study, cassava starch-based edible coating incorporated with lemongrass essential oil (1%) was applied by spraying and dipping methods to preserve papaya MJ9 during storage at room temperature. The quality of papaya MJ9 was analyzed based on its physicochemical and microbiological properties. The addition of lemongrass essential oil (1%) significantly inhibited the microbial growth on papaya MJ9 by reducing the value of total yeast and mold as compared to the control. This study also showed that for parameters of weight loss, total soluble solid, vitamin C, and total titratable acid, papaya MJ9 with cassava starch-based edible coating incorporated with lemongrass essential oil (1%) had the lower values than control, however, they had the higher value than control on firmness parameter. These results indicate that cassava starch-based edible coating incorporated with lemongrass essential oil (1%) can be used as an alternative preservation for papaya MJ9.

  15. Effects of Nano TiO2-Chitosan Coating on the Preservation of Shatang Orange%纳米TiO_2-壳聚糖复合涂膜对砂糖橘的保鲜效果

    Institute of Scientific and Technical Information of China (English)

    解淑慧; 王维琴; 叶卫东; 黄少波; 邵兴锋

    2012-01-01

    以砂糖橘为试验材料,从腐烂果实上分离并鉴定腐败菌,筛选合适的壳聚糖-纳米TiO2复合涂膜,研究该涂膜对砂糖橘采后贮期品质的影响及其体外抑菌效果。结果表明:引起砂糖橘致病的主要真菌为指状青霉(Penicillium digitatum);当涂膜液中壳聚糖、纳米TiO2的质量分数皆为2%时,涂膜组保持较高的果实硬度、可溶性固形物、可滴定酸和VC含量;该复合涂膜还能有效的抑制P.digitatum的生长及其病斑的扩展。%The natural rot Shatang orange fruits were used to isolate and identify the pathogen. , The effects of nano TiO2-chitosan coating on the quality of Shatang orange and inhibition of fungistatic ability in vitro experiment were investigated. The results showed that the main pathogenic fungi on Shatang orange was Penicillium digitatum. The coating contained with 2% chitosan and 2% nano Ti02 can maintain higher firmness, soluble solids and titratable acid and Vc content, significantly reduce the growth of P. digitatum and the lesion diameter. It was suggested that the nano TiO2-chitosan coating can maintain the natural quality and inhibit the postharvest diseases of Shatang orange.

  16. Effect of Chitosan Coating on the Quality of Fresh-cut Pumpkin(Cucurbita Moschata) during Storage%壳聚糖涂膜对鲜切南瓜贮藏品质的影响

    Institute of Scientific and Technical Information of China (English)

    张丹丹; 杨绍兰; 吴昊; 张宏斌; 王成荣

    2012-01-01

    Fresh "MiBen" pumpkins were subjected to coating with chitosan at different concentrations (0.5%, 1.0%, 1.5%)and subsequent storage at 4 ℃ in order to examine the fresh-keeping effect of chitosan coating on fresh-cut pumpkin. During the storage, changes in polysaccharose, carotenoid and total phenol contents, ethylene production, weight loss rate, firmness and the activity of PAL and POD of fresh-cut pumpkin were measured. Results showed that chitosan coating could delay the reductions of firmness, polysaccharose, carotenoid and total phenol contents, and also could delay the increase of ethylene production, obviously enhance PAL and POD activities, reduce weight loss rate, and substantially extend the shelf life of fresh-cut pumpkin, especially at a concentration of 1.0%.%以新鲜的“蜜本”南瓜(Cucurbita moschata)为试验材料,探讨不同质量分数(0.5%、1.0%、1.5%)壳聚糖涂膜液处理对鲜切南瓜贮藏品质的影响.结果表明:采用壳聚糖涂膜液处理,不同程度地延缓了鲜切南瓜乙烯释放量的增加和硬度的下降,阻止了多糖和类胡萝卜素的减少,抑制了POD、PAL酶活性的下降和总酚含量的降低.其中以质量分数为1.0%壳聚糖涂膜液处理的效果最好,有效地保持了鲜切南瓜贮藏期间的品质.

  17. Kanamycin Sulphate Loaded PLGA-Vitamin-E-TPGS Long Circulating Nanoparticles Using Combined Coating of PEG and Water-Soluble Chitosan

    Science.gov (United States)

    Mustafa, Sanaul

    2017-01-01

    Kanamycin sulphate (KS) is a Mycobacterium tuberculosis protein synthesis inhibitor. Due to its intense hydrophilicity, KS is cleared from the body within 8 h. KS has a very short plasma half-life (2.5 h). KS is used in high concentrations to reach the therapeutic levels in plasma, which results in serious nephrotoxicity/ototoxicity. To overcome aforementioned limitations, the current study aimed to develop KS loaded PLGA-Vitamin-E-TPGS nanoparticles (KS-PLGA-TPGS NPs), to act as an efficient carrier for controlled delivery of KS. To achieve a substantial extension in blood circulation, a combined design, affixation of polyethylene glycol (PEG) to KS-PLGA-TPGS NPs and adsorption of water-soluble chitosan (WSC) (cationic deacetylated chitin) to particle surface, was raised for surface modification of NPs. Surface modified NPs (KS-PEG-WSC NPs) were prepared to provide controlled delivery and circulate in the bloodstream for an extended period of time, thus minimizing dosing frequency. In vivo pharmacokinetics and in vivo biodistribution following intramuscular administration were investigated. NPs surface charge was close to neutral +3.61 mV and significantly affected by the WSC coating. KS-PEG-WSC NPs presented striking prolongation in blood circulation, reduced protein binding, and long drew-out the blood circulation half-life with resultant reduced kidney sequestration vis-à-vis KS-PLGA-TPGS NPs. The studies, therefore, indicate the successful formulation development of KS-PEG-WSC NPs with reduced frequency of dosing of KS indicating low incidence of nephrotoxicity/ototoxicity.

  18. Advances in the Application of Chitosan Coating in Fresh-keeping of Fruits and Vegetables%壳聚糖复合涂膜在果蔬保鲜中的应用研究进展

    Institute of Scientific and Technical Information of China (English)

    张洪; 王明力; 毛玉涛

    2011-01-01

    Chitosan is safe and non-toxic to people, which has the advantages of biodegradability and strong antimicrobial activity as a natural food preservative. In recent years, the technology of chitosan coating has become a research focus on storage of fruits and vegetables. In this paper, the studies on application of chitosan in fresh-keeping of fruits and vegetables at home and abroad were reviewed. Moreover, the existing problems and development trends were proposed.%天然食品防腐剂壳聚糖具有易于生物降解、抗菌性强、安全无毒等优点.近年来,壳聚糖复合涂膜保鲜技术已成为保鲜领域的研究热点.笔者从壳聚糖与其他天然防腐剂的复合及改性壳聚糖在果蔬保鲜中的应用等方面,对国内外有关壳聚糖复合物保鲜应用的研究进行了综述,提出了现阶段壳聚糖复合物保鲜技术研究与应用中存在的问题及其今后的研究发展方向.

  19. Combination of Tung oil and Natural Rubber Latex in PVA as Water Based Coatings for Paperboard Application

    Directory of Open Access Journals (Sweden)

    Jianprasert Apichaya

    2015-01-01

    Full Text Available This research is focused on the preparation of the PVA/TO/NRL coatings for paperboard by using poly(vinyl alcohol (PVA as substance and blending with Tung oil (TO and/or natural rubber latex (NRL in order to enhance water resistance and dynamic mechanical properties. The effects of TO: NRL ratios on the structures were investigated by water resistance property and dynamic mechanical thermal analysis (DMA. The results showed that the water resistance property was improved by crosslinking of TO and film forming of NRL. The PVA/TO/NRL coating containing both TO and NRL gave better thermal behavior than those with only TO or NRL. For paperboard application, the PVA/TO/NRL coatings were applied on the paperboard to study water affinity and absorption rate on the coated surface. The rate of contact angle change of water on coated paperboards decreased depending on the ratios of TO and NRL.

  20. Synthesis of sustainable polymers from vegetable oil: Applications in coatings and nanoparticle surface modification

    Science.gov (United States)

    Kalita, Harjyoti

    Polymeric materials are increasing being used in many household, industrial, and health and personal care products. These materials, being either non-degradable or slow degradable, remain in the environment for a long time and are posing increasingly significant threats to the ecosystem components including mammals, birds, fish, reptiles, and crustaceans. Renewable resource based materials are the best raw materials for the development of sustainable products. Vegetable oil and polyglycol based novel copolymers have been synthesized in this research. Poly(2-VOES-r-TEGEVE) copolymers were synthesized from 2-(vinyloxyethyl) soyate (2-VEOS) and tri(ethylene glycol) ethyl vinyl ether (TEGEVE) via cationic polymerization. They were used in waterborne coating as self-dispersible polymers and as surfmers. Four different copolymers were synthesized having 2-VOES wt% as 10, 15, 25, 50 and rest being TEGEVE. In addition to that water insoluble poly(2-VOES) copolymers were synthesized from soybean oil. All copolymers were used as self-dispersible polymers and their coating property were analyzed by measuring glass transition temperature, drying time, gloss, transparency, contact angle, hysteresis, tensile strength, and hardness. Results showed that the coatings can be cured by autoxidation drying process within 6.1 to 8.2 h. Results also showed high transparency (coated in glass panel) with maximum 2% absorbance which is comparable to uncoated substrate (clean glass). Copolymer having 2-VOES wt% 15 and 50 were used as surfmers to disperse poly(2-VOES) and they were cured using autoxidation method. Results showed that the curing of film can be achieved within 2.6 to 8.0 h. High gloss and transparency confirmed that the surfmers get copolymerized with poly(2-VOES). Another set of poly(2-VOES-r-TEGEVE) copolymers with 2-VOES wt% 15, 25, 50, 75 and 85 were synthesized and then functionalized with a carboxyl group. These carboxyl functionalized polymer were used to coat nanoscale

  1. Preservation Effect of Composite Chitosan Coating Treatment on Sea Asparagus%复合壳聚糖涂膜处理对海芦笋保鲜效果的影响

    Institute of Scientific and Technical Information of China (English)

    胡烨; 徐青; 辛建美; 滕宏飞; 罗红宇

    2012-01-01

    Composite chitosan preservative was prepared using chitosan, phytic acid, sodium chloride and orange peel extract according to a certain proportion and storage tests were made at room temperature after sea asparagus immersion and coating. And preservative formula with better preservation effect was selected through orthogonal design. The results showed that each test group of composite chitosan coating could significantly reduce the rot rate and water loss rate of sea asparagus during storage and could effectively delay the oxidation of VC and chlorophyll compared with the control group. The optimized formulation of composite chitosan preservative was chitosan 1.5%, phytic acid 1.5%, sodium chloride 0.2% and orange peel extract 10%. The preservation period of sea asparagus using this formulation could be prolonged for more than 10 days compared with that of the untreated sea asparagus and it can fully meet the requirements of current logistics rate and logistics technology for vegetable preservation period.%壳聚糖、植酸、氯化钠、桔皮提取液按一定比例配制成复合壳、聚糖保鲜剂,在常温下对海芦笋浸泡涂膜后做贮藏试验.采用正交设计筛选保鲜效果较佳的保鲜剂配方.试验结果表明:与空白对照组相比,经复合壳聚糖涂膜处理的各试验组,明显降低海芦笋贮藏期间的腐烂率和失水率,有效延缓VC和叶绿素的氧化.复合壳聚糖涂膜液的优化配方为壳聚糖1.5%,植酸1.5%,氧化钠0.2%,桔度提取液10%(质量分数).经该配方涂膜密封贮藏的海芦笋比未处理的海芦笋保鲜期延长10d以上,可以满足目前物流速率和物流技术对蔬菜保鲜期的要求.

  2. Chitosan-coated poly(lactic-co-glycolic acid nanoparticles as an efficient delivery system for Newcastle disease virus DNA vaccine

    Directory of Open Access Journals (Sweden)

    Zhao K

    2014-09-01

    Full Text Available Kai Zhao,1,* Yang Zhang,1,2,* Xiaoyan Zhang,1,* Ci Shi,1,2 Xin Wang,1 Xiaohua Wang,1 Zheng Jin,3 Shangjin Cui2 1Laboratory of Microbiology, School of Life Science, Heilongjiang University, 2Division of Swine Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, 3Key Laboratory of Chemical Engineering Process and Technology for High-efficiency Conversion, Heilongjiang University, Harbin, People’s Republic of China *These authors contributed equally to this work Abstract: We determined the efficacy and safety of chitosan (CS-coated poly(lactic-co-glycolic acid (PLGA nanoparticles (NPs as a delivery system for a vaccine to protect chickens against Newcastle disease virus (NDV. The newly constructed vaccine contained DNA (the F gene of NDV. The Newcastle disease virus (NDV F gene deoxyribonucleic acid (DNA plasmid (pFDNA-CS/PLGA-NPs were spherical (diameter =699.1±5.21 nm [mean ± ­standard deviation] and smooth, with an encapsulation efficiency of 98.1% and a Zeta potential of +6.35 mV. An in vitro release assay indicated that CS controlled the burst release of plasmid DNA, such that up to 67.4% of the entire quantity of plasmid DNA was steadily released from the pFDNA-CS/PLGA-NPs. An in vitro expression assay indicated that the expression of nanoparticles (NPs was maintained in the NPs. In an immunization test with specific pathogen-free chickens, the pFDNA-CS/PLGA-NPs induced stronger cellular, humoral, and mucosal immune responses than the plasmid DNA vaccine alone. The pFDNA-CS/PLGA-NPs did not harm 293T cells in an in vitro assay and did not harm chickens in an in vivo assay. Overall, the results indicated that CS-coated PLGA NPs can serve as an efficient and safe mucosal immune delivery system for NDV DNA vaccine.Keywords: mucosal immune delivery system, immune effect

  3. Application of lemon peel essential oil with edible coating agent to prolong shelf life of tofu and strawberry

    Science.gov (United States)

    Rahmawati, Della; Chandra, Mega; Santoso, Stefanus; Puteri, Maria Gunawan

    2017-01-01

    The essential oil of sweet orange, lemon, and key lime peel were analyzed for their antimicrobial activity. The antimicrobial activity of each citrus essential oil with different concentration was assessed using broth macro-dilution against Bacillus sp, Eschericia coli, Rhizopus stolonifer, and Botrytis sp which represented specific spoilage microorganism in tofu and fresh strawberry. Among all the citrus peel essential oils tested, lemon peel essential oil with 0.6% concentration showed significant activity as an antimicrobial agent against Escherichia coli and Bacillus sp. In other hand 1% of lemon peel essential oil is also considered to be the best concentration of inhibiting the Rhizopus Stolonifer and Botrytis sp. Lemon peel essential oil which has the highest antimicrobial activity was combined with two different kind of edible coating agents (cassava starch and sodium alginate) and was applied in both tofu and strawberry to observe whether it had possibility to decrease the degradation rate of tofu and strawberry. The addition of 0.6% and 1% lemon peel essential oil with each of edible coating agents was significantly able to reduce the degradation of tofu and fresh strawberry.

  4. Alginate gel-coated oil-entrapped alginate-tamarind gum-magnesium stearate buoyant beads of risperidone.

    Science.gov (United States)

    Bera, Hriday; Boddupalli, Shashank; Nandikonda, Sridhar; Kumar, Sanoj; Nayak, Amit Kumar

    2015-01-01

    A novel alginate gel-coated oil-entrapped calcium-alginate-tamarind gum (TG)-magnesium stearate (MS) composite floating beads was developed for intragastric risperidone delivery with a view to improving its oral bioavailability. The TG-blended alginate core beads containing olive oil and MS as low-density materials were accomplished by ionotropic gelation technique. Effects of polymer-blend ratio (sodium alginate:TG) and crosslinker (CaCl2) concentration on drug entrapment efficiency (DEE, %) and cumulative drug release after 8 h (Q8h, %) were studied to optimize the core beads by a 3(2) factorial design. The optimized beads (F-O) exhibited DEE of 75.19±0.75% and Q8h of 78.04±0.38% with minimum errors in prediction. The alginate gel-coated optimized beads displayed superior buoyancy and sustained drug release property. The drug release profiles of the drug-loaded uncoated and coated beads were best fitted in Higuchi kinetic model with Fickian and anomalous diffusion driven mechanisms, respectively. The optimized beads yielded a notable sustained drug release profile as compared to marketed immediate release preparation. The uncoated and coated Ca-alginate-TG-MS beads were also characterized by SEM, FTIR and P-XRD analyses. Thus, the newly developed alginate-gel coated oil-entrapped alginate-TG-MS composite beads are suitable for intragastric delivery of risperidone over a prolonged period of time.

  5. Chitosan in Mucoadhesive Drug Delivery: Focus on Local Vaginal Therapy

    Directory of Open Access Journals (Sweden)

    Toril Andersen

    2015-01-01

    Full Text Available Mucoadhesive drug therapy destined for localized drug treatment is gaining increasing importance in today’s drug development. Chitosan, due to its known biodegradability, bioadhesiveness and excellent safety profile offers means to improve mucosal drug therapy. We have used chitosan as mucoadhesive polymer to develop liposomes able to ensure prolonged residence time at vaginal site. Two types of mucoadhesive liposomes, namely the chitosan-coated liposomes and chitosan-containing liposomes, where chitosan is both embedded and surface-available, were made of soy phosphatidylcholine with entrapped fluorescence markers of two molecular weights, FITC-dextran 4000 and 20,000, respectively. Both liposomal types were characterized for their size distribution, zeta potential, entrapment efficiency and the in vitro release profile, and compared to plain liposomes. The proof of chitosan being both surface-available as well as embedded into the liposomes in the chitosan-containing liposomes was found. The capability of the surface-available chitosan to interact with the model porcine mucin was confirmed for both chitosan-containing and chitosan-coated liposomes implying potential mucoadhesive behavior. Chitosan-containing liposomes were shown to be superior in respect to the simplicity of preparation, FITC-dextran load, mucoadhesiveness and in vitro release and are expected to ensure prolonged residence time on the vaginal mucosa providing localized sustained release of entrapped model substances.

  6. Effect of chitosan/nano-ZnO coating on the quality of cherry tomato%壳聚糖/纳米ZnO涂膜对圣女果的保鲜作用

    Institute of Scientific and Technical Information of China (English)

    李亚娜

    2013-01-01

    The effect of mixing chitosan/nano-ZnO coating with different content of nano-ZnO on quality of cherry tomato was studied.The SEM pictures showed that the nanoparticles had a better dispersion in chitosan matrix at a relative low content of 1% and 2%.However, the aggregation of nanoparticles occurred when the content of nano-ZnO was up to 3wt%.The chitosan/nano-ZnO coating with 1% content of nano-ZnO had a better preservation effect on improving the sensory quality, decreasing the weight loss, Vc and acid content of cherry tomato.In contrast, the chitosan/nano-ZnO coating (2% and 3% content of nano-ZnO) showed little fresh-keeping effect on cherry tomato.%通过溶液共混制备得到不同纳米ZnO含量的壳聚糖/纳米ZnO涂液,观测了该涂膜的微观结构,并考察了其对圣女果的保鲜性.结果发现:当纳米ZnO含量较低(1%和2%)时,纳米粒子较均匀的分散于壳聚糖膜中.但当纳米ZnO含量增加到3%时,纳米ZnO出现了团聚.保鲜实验发现,纳米ZnO含量为1%的壳聚糖/纳米ZnO涂膜能够最大程度的提高圣女果的感官品质、降低其失重率,并减少其在贮藏过程中Vc及可滴定酸含量的损失.而纳米ZnO含量为2%和3%的壳聚糖/纳米ZnO涂膜的保鲜效果不明显.

  7. The Effect of N-trimethyl Chitosan as Coating Materials on Corneal Permeability of Curcu-min%姜黄素眼用脂质体的角膜透过性研究

    Institute of Scientific and Technical Information of China (English)

    张婧; 李翔; 罗云; 梁新丽; 廖正根

    2015-01-01

    Objective:To study the effect of N-trimethyl chitosan as coating materials on corneal permeability of curcumin.Methods:Curcumin-loaded liposomes were prepared by ethanol injection method, and the vesicles were coated with trimethyl chitosan.Mem-brane filter, dynamic light scattering and electrophoretic light scattering were employed to study the physicochemical parameters.Cor-neal permeability of trimethyl chitosan-coated liposomes was carried out by transcorneal permeation study and confocal laser scanning microscopy ( CLSM) .Results:It was shown that the entrapment efficiency was not changed significantly with enlarged size and zeta po-tential with the coating of TMC.The TMC-coated liposomes produced the more pronounced corneal permeation, compared with the uncoated preparations.With the increased contact time, the fluorescence in rabbit corneal epithelium can be detected down to 60 μm below the surface via paracellular route.Conclusion:TMC has significant effect on the transport of curcumin through rabbit cornea in vitro.%目的:研究姜黄素眼用脂质体的角膜透过性。方法:采用乙醇注入法制备姜黄素脂质体,以三甲基壳聚糖对脂质体囊泡进行包覆;采用过膜法、粒径及电位测定仪对脂质体进行理化性质分析;采用离体兔角膜透过实验及共聚焦激光扫描显微镜成像技术,对三甲基壳聚糖包覆的脂质体的角膜透过作用进行研究。结果:三甲基壳聚糖对脂质体的包覆对脂质体的包封率无明显影响,但粒径、电位有所增大,同时角膜透过显著高于未包覆脂质体组,随着作用时间的延长,可促进脂质体囊泡渗透至角膜上皮深层60μm处,并主要以细胞旁路途径发生角膜透过。结论:该研究表明三甲基壳聚糖对脂质体囊泡具有明显的角膜促透作用。

  8. Electro-rheological properties of montmorillonite particles coated with titania in methyl silicone oil

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xu-ping; XU Ling-li; WANG Qing-liang

    2008-01-01

    Montmorillonite particles coated with titania were synthesized by means of a sol-gel method to use with elec-tro-theological material. The characteristics of these composite particles were studied by X-ray diffraction, scanning electron mi-croscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). The electro-rheological (ER) effects were measured after these particles were mixed with methyl-silicon oil by 20% and 30% (weight percent). The experimental results show that these montmorillonite/titania particles exhibit a marked ER effect compared with pure montmorillonite particles under a DC electric field.The highest static yield stress is up to 4.28 kPa, which is an increase of about 3.13 kPa over that of untreated montmorillonite pow-der under the electrical field strength of 3.2 kV/mm at room temperature.

  9. 壳聚糖涂膜保藏技术在卤鹅加工中的应用%Application of Coating Storage Technology with Chitosan in Sauce and Pot-roast Goose Processing

    Institute of Scientific and Technical Information of China (English)

    张晓春; 葛良鹏; 欧秀琼; 景绍红; 杜金平

    2013-01-01

    Study of the composite preserving techniques of sauce and pot-roast gooses were carried out by the coating storage technology with chitosan, natural biologic preservatives, vacuum packaging technology and pasteurized repasteurization. The result showed that the shelf-life of sauce and pot-roast goose could extended to 4 weeks at 30℃-35℃by coating the surface of sauce and pot-roast goose with the solutions containing 1%chitosan,1%Nisin and 0.2%acetic acid, then combined with vacuum packaging, pasteurized repasteurization treatment(80℃-85℃,heating 5 min).%  采用壳聚糖涂膜保藏技术,结合天然生物防腐剂、真空包装及低温二次杀菌技术,对卤鹅综合保鲜技术进行了研究.结果表明:利用复配的壳聚糖涂膜液(含1%壳聚糖、1%Nisin和0.2%醋酸)对卤鹅表面作涂膜,然后真空包装,低温二次杀菌(80℃~85℃,5 min)处理,卤鹅在常温下(30℃~35℃)的货架期可达到4周.

  10. Adsorption and preconcentration of divalent metal ions in fossil fuels and biofuels: gasoline, diesel, biodiesel, diesel-like and ethanol by using chitosan microspheres and thermodynamic approach.

    Science.gov (United States)

    Prado, Alexandre G S; Pescara, Igor C; Evangelista, Sheila M; Holanda, Matheus S; Andrade, Romulo D; Suarez, Paulo A Z; Zara, Luiz F

    2011-05-15

    Biodiesel and diesel-like have been obtained from soybean oil by transesterification and thermal cracking process, respectively. These biofuels were characterized as according to ANP standards by using specific ASTM methods. Ethanol, gasoline, and diesel were purchased from a gas station. Deacetylation degree of chitosan was determined by three distinct methods (conductimetry, FTIR and NMR), and the average degree was 78.95%. The chitosan microspheres were prepared from chitosan by split-coating and these spheres were crosslinked using glutaraldehyde. The surface area of microspheres was determined by BET method, and the surface area of crosslinked microspheres was 9.2m(2)g(-1). The adsorption isotherms of cooper, nickel and zinc on microspheres of chitosan were determined in petroleum derivatives (gasoline and diesel oil), as well as in biofuels (alcohol, biodiesel and diesel-like). The adsorption order in all fuels was: Cu>Ni>Zn. The elution tests presented the following preconcentration degrees: >4.5 to ethanol, >4.4 to gasoline, >4.0 to diesel, >3.8 to biodiesel and >3.6 to diesel-like. The application of chitosan microspheres in the metal ions preconcentration showed the potential of this biopolymer to enrich fuel sample in order to be analyzed by flame atomic absorption spectrometry.

  11. Surfactant-coated Candida rugosa Lipase as Catalyst for Hydrolysis of Olive Oil in Solvent-Free Two-Phase System

    Institute of Scientific and Technical Information of China (English)

    宋宝东; 丁辉; 吴金川; HayashiY.; TalukderMMR; 王世昌

    2003-01-01

    The surfactant-coated Candida rugosa lipase was used as catalyst for hydrolysis of olive oil in two-phase system consisting of olive oil and phosphate buffer without organic solvent. For both the coated and native lipases,the optimal buffer/oil volume ratio of 1.0, aqueous pH 6.8 and reaction temperature 30℃ were determined. The maximum activity of the coated lipase was ca 1.3 times than that of the native lipase. The half-life of the coated lipase in olive oil and the native lipase in phosphate buffer was ca 9 h and 12 h, and the final residual activity was 27% and 20% of their initial values, respectively. The final substrate conversion by the coated lipase was ca 20% higher than that of the native lipase.

  12. Structure, properties and application to water-soluble coatings of complex antimicrobial agent Ag-carboxymethyl chitosan-thiabendazole

    Institute of Scientific and Technical Information of China (English)

    XIA Jin-lan; WANG Chun; NIE Zhen-yuan; Peng An-an; Guan Xin

    2005-01-01

    The structure, properties and application to water-soluble coatings of a new complex antimicrobial agent Ag-carboxylmethyl citosan-thiabendazole (Ag-CMCTS-TBZ) prepared from different materiel ratios were reported. The silver ions were preferably coordinated with the free -NH2 groups and the -OH groups of secondary alcohol and carboxyl in CMCTS. TBZ preferably bonded to carboxyl group in CMCTS by electrostatic force and hydrogen bonding. Increase in silver ions content in the complex agent improved to some limited extent the antibacterial activity, but enhanced coloring and cost of the complex agent. Increase in TBZ content resulted in increase of antifungal activity, but decrease of water solubility of the complex agent. The antimicrobial MICs of the complex agent to Esherichia coli, Staphylococcus aureus, Candida albicans, Aspergillus niger, Mucor sp. were 20-80, 15-60, 20-55, 40-250, and 400-1 700 mg/kg, respectively. Addition of 0.1% of this complex agent to acrylic emulsion paint made the paint without substantial change in color, luster, viscosity, odor or pH value, but with an excellent and chronically persisting broad-spectra antimicrobial activity.

  13. Preparation and characterisation of irradiated crab chitosan and New Zealand Arrow squid pen chitosan

    Energy Technology Data Exchange (ETDEWEB)

    Shavandi, Amin, E-mail: amin.shavandi@postgrad.otago.ac.nz [Department of Food Sciences, University of Otago, Dunedin (New Zealand); Bekhit, Adnan A. [Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Alexandria, Alexandria (Egypt); Bekhit, Alaa El-Din A. [Department of Food Sciences, University of Otago, Dunedin (New Zealand); Sun, Zhifa [Department of Physics, University of Otago, Dunedin (New Zealand); Ali, M. Azam [Department of Applied Sciences, University of Otago, Dunedin (New Zealand)

    2015-11-01

    The properties of chitosan from Arrow squid (Nototodarus sloanii) pen (CHS) and commercial crab shell (CHC) were investigated using FTIR, DSC, SEM and XRD before and after irradiation at the dose of 28 kGy in the presence or absence of 5% water. Also, the viscosity, deacetylation degree, water and oil holding capacities, colour and antimicrobial activities of the chitosan samples were determined. Irradiation decreased (P < 0.05) the viscosity of CHC from 0.21 to 0.03 Pa s and of CHS from 1.71 to 0.23 Pa s. The inclusion of water had no effect on the viscosity of irradiated chitosan. Irradiation did not affect the degree of deacetylation of CHC, but increased the deacetylation degree of CHS from 72.78 to 82.29% in samples with 5% water. Water and oil holding capacities of CHS (1197.30% and 873.3%, respectively) were higher (P < 0.05) than those found in CHC (340.70% and 264.40%, respectively). The water and oil holding capacities were decreased for both types of chitosan irradiation, but were not affected by the addition of water. Squid pen chitosan was whiter in colour (White Index = 90.06%) compared to CHC (White Index = 83.70%). Generally, the CHC samples (control and irradiated) exhibited better antibacterial activity compared to CHS, but the opposite was observed with antifungal activity. - Highlights: • Chitosan prepared from Arrow squid pens (Nototodarus sloanii). • Chitosan samples were gamma irradiated at 28 kGy. • Squid pen chitosan showed high fat and water uptake capacities compared to crab shell chitosan. • Gamma irradiation enhanced the DDA of squid pen chitosan but not crab shell chitosan.

  14. Lipase immobilized on polydopamine-coated magnetite nanoparticles for biodiesel production from soybean oil

    Directory of Open Access Journals (Sweden)

    Marcos F. C. Andrade

    2016-06-01

    Full Text Available Lipase from Pseudomonas cepacia was covalently attached to magnetite nanoparticles coated with a thin polydopamine film, and employed in the enzymatic conversion of soybean oil into biodiesel, in the presence of methanol.  The proposed strategy explored the direct immobilization of the enzyme via Michael addition and aldolic condensation reactions at the catechol rings, with no need of using specific coupling agents. In addition, a larger amount of enzymes could be bound to the magnetic nanoparticles, allowing their efficient recycling with the use of an external magnet. In the biodiesel conversion, the transesterification reaction was carried out directly in soybean oil by the stepwise addition of methanol, in order to circumvent its inactivation effect on the enzyme. A better yield was  obtained in relation to the free enzyme, achieving 90% yield at 37 oC.  However, the catalysis became  gradually less effective after the third cycle, due to its prolonged exposition to the denaturating methanol medium.

  15. The addition of rosehip oil to Aloe gels improves their properties as postharvest coatings for maintaining quality in plum.

    Science.gov (United States)

    Martínez-Romero, Domingo; Zapata, Pedro J; Guillén, Fabián; Paladines, Diego; Castillo, Salvador; Valero, Daniel; Serrano, María

    2017-02-15

    The effect of Aloe vera gel (AV) and Aloe arborescens gel (AA) alone or in combination with rosehip oil (RO) at 2% on ethylene production, respiration rate, quality parameters, bioactive compounds and antioxidant activity during plum postharvest storage was studied. Coated plums showed a delay in ethylene production and respiration rate at 20°C and during cold storage and subsequent shelf life, the main effect being observed for those fruits coated with AA+RO. Quality parameters such as softening, colour and maturity index was also delayed during storage by the use of the coatings, which led to a 2-fold increase in plum storability. Accumulation of bioactive compounds was also delayed although at the end of the experiment the content of bioactive compounds was higher than those found for control fruits at the estimated shelf life. The most effective coating for maintaining plum quality and bioactive compounds was AA+RO.

  16. Preparation and Characterization of Chitosan /Ethylcellulose Complex Microcapsule

    Institute of Scientific and Technical Information of China (English)

    史新元; 谭天伟

    2003-01-01

    In this work a system which consists of chitosan microcores entrapped in ethylcellulose is presented.Vitamin D2 was eficiently entrapped in chitosan microcores with spray-drying method and was microencapsulated by coating of ethylcellulose.The average size of chitosan microspheres was 6.06μm.The morphology and release properties of microcapsules were tested.The results of release in vitro showed that the microcapsule could realize sustained release for 12h in artificial intestinal juice.

  17. Ionically Crosslinked Chitosan Hydrogels for the Controlled Release of Antimicrobial Essential Oils and Metal Ions for Wound Management Applications

    OpenAIRE

    Wan Li Low; Kenward, M A; Mohd Cairul Iqbal Mohd Amin; Claire Martin

    2016-01-01

    The emerging problems posed by antibiotic resistance complicate the treatment regime required for wound infections and are driving the need to develop more effective methods of wound management. There is growing interest in the use of alternative, broad spectrum, pre-antibiotic antimicrobial agents such as essential oils (e.g., tea tree oil, TTO) and metal ions (e.g., silver, Ag+). Both TTO and Ag+ have broad spectrum antimicrobial activity and act on multiple target sites, hence reducing the...

  18. Synthesis and evaluation of antibacterial polyurethane coatings made from soybean oil functionalized with dimethylphenylammonium iodide and hydroxyl groups.

    Science.gov (United States)

    Bakhshi, Hadi; Yeganeh, Hamid; Mehdipour-Ataei, Shahram

    2013-06-01

    Preparation of antibacterial polyurethane coatings from novel functional soybean oil was considered in this work. First, epoxidized soybean oil (ESBO) as a low price and widely available renewable resource raw material was subjected to the reaction with aniline using an ionic liquid as a green catalyst. The intermediate phenylamine containing polyol (SAP) was then methylated by reaction with methyl iodide to produce a polyol (QAP) with pendant dimethylphenylammonium iodide groups. To regulate the physical and mechanical properties as well as biological characteristics of final coatings, QAP was mixed with different portions of a similar soybean oil-based polyol (MSP) without quaternary ammonium groups. The mixtures were reacted with isophorone diisocyanate to produce crosslinked polyurethane coatings. Evaluation of viscoelastic properties by DMA method revealed single phase structure with Tg in the range of 50-82°C. Stress-strain analysis of the prepared polyurethanes showed initial modulus, tensile strength, and elongation at break in the ranges of 13-299 MPa, 4.5-13.8 MPa, and 16-109%, respectively. Additionally, the coatings showed good adherence to aluminum and PVC substrates. The solvent extracted samples showed excellent biocompatibility as determined by monitoring L929 fibroblast cells morphology and MTT assay. Meanwhile, very promising antibacterial properties against both Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria with bacterial reduction in the range of 83-100% was observed.

  19. Electrospun antibacterial chitosan-based fibers.

    Science.gov (United States)

    Ignatova, Milena; Manolova, Nevena; Rashkov, Iliya

    2013-07-01

    Chitosan is non-toxic, biocompatible, and biodegradable polysaccharide from renewable resources, known to have inherent antibacterial activity, which is mainly due to its polycationic nature. The combining of all assets of chitosan and its derivatives with the unique properties of electrospun nanofibrous materials is a powerful strategy to prepare new materials that can find variety of biomedical applications. In this article the most recent studies on different approaches for preparation of antibacterial fibrous materials from chitosan and its derivatives such as electrospinning, coating, and electrospinning-electrospraying, loading of drugs or bioactive nanoparticles are summarized.

  20. PENGARUH MINYAK ATSIRI JAHE MERAH DAN LENGKUAS MERAH PADA EDIBLE COATING TERHADAP KUALITAS FILLET IKAN PATIN (Effect of Edible Coating Enriched with Red Ginger and Red Galangal Essential Oil on the Quality of Patin Fillet)

    OpenAIRE

    Rohula Utami; Kawiji Kawiji; Edhi Nurhartadi; Muslika Kurniasih; Dedy Indianto

    2014-01-01

    The effects of edible coating enriched with red ginger and red galangal essential oil on the quality of patin fillets during refrigerated storage of 8 days were examined. fish quality determined was based on microbiological (Total Plate Count /TPc) and physicochemical (Total Volatile Bases/TVB, Thiobarbituricacid/TBa, pH, and color) quality. Treatment variation of patin fillets were essential oil concentration enriched in edible coating (0 %, 0.1%, 1%). The results indicated that both red gin...

  1. Spontaneous changes in contact angle of water and oil on novel flip-flop-type hydrophobic multilayer coatings

    Science.gov (United States)

    Kawamura, Go; Ema, Tomoyuki; Sakamoto, Hisatoshi; Wei, Xing; Muto, Hiroyuki; Matsuda, Atsunori

    2014-04-01

    Multilayer structures composed of poly(allylamine hydrochloride) (PAH) and Nafion were fabricated on glass substrates by layer-by-layer assembly. Some of the multilayers demonstrated spontaneous changes in contact angle of water and oil due to flip-flop movements of free sulfo groups in the Nafion layer, and the multilayers eventually possessed water repellency in air and oil repellency in water. The repellencies were enhanced by applying primer layers that were formed using SiO2 fine particles to increase surface roughness. Compared to typical hydrophobic and oleophobic surfaces, the multilayers showed practical levels for a use as soil release coatings.

  2. Study on Immobilization of Acetylcholinesterase with Filter Paper Coated with Chitosan%滤纸壳聚糖膜固定乙酰胆碱酯酶的研究

    Institute of Scientific and Technical Information of China (English)

    郭尽力; 姜爱莉; 于贞; 郑舒文

    2012-01-01

    [目的]探索滤纸壳聚糖膜固定乙酰胆碱酯酶( AChE)的最佳条件.[方法]以滤纸壳聚糖膜为我体,戊二醛为交联剂,牛血清白蛋白( BSA)为保护剂,进行AChE的固定.并对固定化酶的理化性质进行研究.[结果]固定AChE的最佳条件为将50μl150 U/mlAChE液,50 μl 5%(V/V)戊二醛溶液,100μl1%(W/W) BSA,pH 8.0的0.2 mol/L的PBS缓冲液配制成1 ml酶液,滤纸壳聚糖膜浸于该酶液4℃固定8h.固定化酶的最适反应温度为37℃,最适pH为8.0,能够重复利用4次以上.[结论]该研究为利用AChE快速检测蔬菜水果中有机磷农药残留提供了理论依据.%[Objective] The aim was to explore the optimum immobilized conditions of acetylcholinesterase on filter paper coated with chitosan. [Method] Acetylcholinesterase was immobilized on filter paper coated with chitosan using glutaraldehyde as cross-linking reagent, bovine serum albumin as protective agent. And the physical and chemical properties of the immobilized enzyme were studied. [Result] The optimal immobilized conditions were as follows: 1 ml solution was prepared with 50 μl 150 U/ml acetylcholinesterase solution, 50 μl 5% ( V/V) glutaraldehyde, 100 μl 1% (W/W) BSA and 0.2 mol/L phosphate buffer(pH 8.0) , and then the filter paper coated with chitosan was immersed for 8 h at 4 ℃.. The optimum temperature of the immobilized acetylcholinesterase was 37 ℃ , the optimum pH was 8.0, and its could be reused four times. [ Conclusion] The study provides a theory basis for rapid determination of organophosphorus pesticide residues in vegetables and fruits.

  3. Functionalization of Titanium with Chitosan via Silanation: Evaluation of Biological and Mechanical Performances

    Science.gov (United States)

    Renoud, Pauline; Toury, Bérangère; Benayoun, Stéphane; Attik, Ghania; Grosgogeat, Brigitte

    2012-01-01

    Complications in dentistry and orthopaedic surgery are mainly induced by peri-implant bacterial infections and current implant devices do not prevent such infections. The coating of antibacterial molecules such as chitosan on its surface would give the implant bioactive properties. The major challenge of this type of coating is the attachment of chitosan to a metal substrate. In this study, we propose to investigate the functionalization of titanium with chitosan via a silanation. Firstly, the surface chemistry and mechanical properties of such coating were evaluated. We also verified if the coated chitosan retained its biocompatibility with the peri-implant cells, as well as its antibacterial properties. FTIR and Tof-SIMS analyses confirmed the presence of chitosan on the titanium surface. This coating showed great scratch resistance and was strongly adhesive to the substrate. These mechanical properties were consistent with an implantology application. The Chitosan-coated surfaces showed strong inhibition of Actinomyces naeslundii growth; they nonetheless showed a non significant inhibition against Porphyromonas gingivalis after 32 hours in liquid media. The chitosan-coating also demonstrated good biocompatibility to NIH3T3 fibroblasts. Thus this method of covalent coating provides a biocompatible material with improved bioactive properties. These results proved that covalent coating of chitosan has significant potential in biomedical device implantation. PMID:22859940

  4. Functionalization of titanium with chitosan via silanation: evaluation of biological and mechanical performances.

    Science.gov (United States)

    Renoud, Pauline; Toury, Bérangère; Benayoun, Stéphane; Attik, Ghania; Grosgogeat, Brigitte

    2012-01-01

    Complications in dentistry and orthopaedic surgery are mainly induced by peri-implant bacterial infections and current implant devices do not prevent such infections. The coating of antibacterial molecules such as chitosan on its surface would give the implant bioactive properties. The major challenge of this type of coating is the attachment of chitosan to a metal substrate. In this study, we propose to investigate the functionalization of titanium with chitosan via a silanation. Firstly, the surface chemistry and mechanical properties of such coating were evaluated. We also verified if the coated chitosan retained its biocompatibility with the peri-implant cells, as well as its antibacterial properties. FTIR and Tof-SIMS analyses confirmed the presence of chitosan on the titanium surface. This coating showed great scratch resistance and was strongly adhesive to the substrate. These mechanical properties were consistent with an implantology application. The Chitosan-coated surfaces showed strong inhibition of Actinomyces naeslundii growth; they nonetheless showed a non significant inhibition against Porphyromonas gingivalis after 32 hours in liquid media. The chitosan-coating also demonstrated good biocompatibility to NIH3T3 fibroblasts. Thus this method of covalent coating provides a biocompatible material with improved bioactive properties. These results proved that covalent coating of chitosan has significant potential in biomedical device implantation.

  5. Functionalization of titanium with chitosan via silanation: evaluation of biological and mechanical performances.

    Directory of Open Access Journals (Sweden)

    Pauline Renoud

    Full Text Available Complications in dentistry and orthopaedic surgery are mainly induced by peri-implant bacterial infections and current implant devices do not prevent such infections. The coating of antibacterial molecules such as chitosan on its surface would give the implant bioactive properties. The major challenge of this type of coating is the attachment of chitosan to a metal substrate. In this study, we propose to investigate the functionalization of titanium with chitosan via a silanation. Firstly, the surface chemistry and mechanical properties of such coating were evaluated. We also verified if the coated chitosan retained its biocompatibility with the peri-implant cells, as well as its antibacterial properties. FTIR and Tof-SIMS analyses confirmed the presence of chitosan on the titanium surface. This coating showed great scratch resistance and was strongly adhesive to the substrate. These mechanical properties were consistent with an implantology application. The Chitosan-coated surfaces showed strong inhibition of Actinomyces naeslundii growth; they nonetheless showed a non significant inhibition against Porphyromonas gingivalis after 32 hours in liquid media. The chitosan-coating also demonstrated good biocompatibility to NIH3T3 fibroblasts. Thus this method of covalent coating provides a biocompatible material with improved bioactive properties. These results proved that covalent coating of chitosan has significant potential in biomedical device implantation.

  6. Mechanically durable, superoleophobic coatings prepared by layer-by-layer technique for anti-smudge and oil-water separation

    OpenAIRE

    Philip S. Brown; Bhushan, Bharat

    2015-01-01

    Superoleophobic surfaces are of interest for anti-fouling, self-cleaning, anti-smudge, low-drag, anti-fog, and oil-water separation applications. Current bioinspired surfaces are of limited use due to a lack of mechanical durability. A so-called layer-by-layer approach, involving charged species with electrostatic interactions between layers, can provide the flexibility needed to improve adhesion to the substrate while providing a low surface tension coating at the air interface. In this work...

  7. Friction and Wear Characteristics of Brush Plating Ni/nano-Al2O3 Composite Coating under Sand-Containing Oil

    Institute of Scientific and Technical Information of China (English)

    Lingzhong DU; Binshi XU; Shiyun DONG; Xin LI; Hua YANG; Weiyi TU; Zixin ZHU

    2005-01-01

    Ni-matrix composite coating containing Al2O3 nano-particles is prepared by brush plating. The effects of the nanoparticles on the microstructure, microhardness and tribological properties of the composite coating under the lubrication of a diesel oil containing sand are investigated. The results show that the microstructure of the composite coating is finer than that of the pure nickel coating due to the codeposition of the nano-particles. When the nano-particle concentration in the electroplating bath reaches 20 g/L, the microhardness, and wear resistance of the composite coating is as much as 1.6 times and 1.3~2.5 times of those of the pure nickel coating respectively. The main hardening mechanism of the composite coating is superfine crystal grain strengthening and dispersion strengthening. The composite coating is characterized by scuffing as it slides against Si3N4 under the present test conditions.

  8. Development of Self-Healing Coatings Based on Linseed Oil as Autonomous Repairing Agent for Corrosion Resistance

    Directory of Open Access Journals (Sweden)

    Karan Thanawala

    2014-11-01

    Full Text Available In recent years corrosion-resistant self-healing coatings have witnessed strong growth and their successful laboratory design and synthesis categorises them in the family of smart/multi-functional materials. Among various approaches for achieving self-healing, microcapsule embedment through the material matrix is the main one for self-healing ability in coatings. The present work focuses on optimizing the process parameters for developing microcapsules by in-situ polymerization of linseed oil as core and urea-formaldehyde as shell material. Characteristics of these microcapsules with respect to change in processing parameters such as stirring rate and reaction time were studied by using optical microscopy (OM, scanning electron microscopy (SEM and Fourier transform infrared spectroscopy (FT-IR. The effectiveness of these microcapsules in coatings was characterized by studying their adhesion, performance, and mechanical properties.

  9. Synthesis of polyurethane/clay nanocomposites based palm oil polyol coating

    Directory of Open Access Journals (Sweden)

    Teuku Rihayat

    2015-12-01

    Full Text Available In this study, we investigated the Polyurethane paint based on palm oil with the addition of nanoparticles montmorillonite as a heat-resistant. The composites with 1 wt%, 3 wt% and 5 wt% of bentonite filler content obtained by synthesizing in situ were investigated and compared to the neat polyurethane matrix material. The processing of bentonite for montmorillonite was done through several stages including: sedimentation, ultrasonication, dried, sieved with a 200 mesh sieve, then characterized. Untreated MMT were isolated and modified with CTAB. The addition of MMT into polyurethane, as much as 5% wt, can increase the heat as evidenced by the TGA test. The TGA results indicated an enhanced thermal stability, as compared to the neat polyurethane. The onset degradation of neat polyurethane and weight reduction began at a temperature of 50-150°C and completely decomposed at the temperatures of 380°C and for PU MKS-MMT reduction, the initial weight started at a temperature of 150-200°C in 5 %wt and decomposed in the end at a temperature of 490°C. In this research, we also tested the gloss adhesive polyurethane with the addition of MMT; the result stated that the addition of 5%wt MMT can improve the adhesion of polyurethane. The addition of MMT in polyurethane can also enhance the gloss polyurethane compared with polyurethane coated without the addition of MMT.

  10. Bioinspired, roughness-induced, water and oil super-philic and super-phobic coatings prepared by adaptable layer-by-layer technique

    Science.gov (United States)

    Brown, Philip S.; Bhushan, Bharat

    2015-09-01

    Coatings with specific surface wetting properties are of interest for anti-fouling, anti-fogging, anti-icing, self-cleaning, anti-smudge, and oil-water separation applications. Many previous bioinspired surfaces are of limited use due to a lack of mechanical durability. Here, a layer-by-layer technique is utilized to create coatings with four combinations of water and oil repellency and affinity. An adapted layer-by-layer approach is tailored to yield specific surface properties, resulting in a durable, functional coating. This technique provides necessary flexibility to improve substrate adhesion combined with desirable surface chemistry. Polyelectrolyte binder, SiO2 nanoparticles, and silane or fluorosurfactant layers are deposited, combining surface roughness and necessary chemistry to result in four different coatings: superhydrophilic/superoleophilic, superhydrophobic/superoleophilic, superhydrophobic/superoleophobic, and superhydrophilic/superoleophobic. The superoleophobic coatings display hexadecane contact angles >150° with tilt angles 160° with tilt angles <2°. One coating combines both oleophobic and hydrophobic properties, whilst others mix and match oil and water repellency and affinity. Coating durability was examined through the use of micro/macrowear experiments. These coatings display transparency acceptable for some applications. Fabrication via this novel combination of techniques results in durable, functional coatings displaying improved performance compared to existing work where either durability or functionality is compromised.

  11. 气管导管壳聚糖涂膜的制备与性能研究%Preparation and Characterization of Chitosan Plastics Coated on the Endotracheal Tube

    Institute of Scientific and Technical Information of China (English)

    王彦荣; 白锡波; 高敬华; 董爱琴; 胡金树; 顾吉顺

    2011-01-01

    Objective: To prepare chitosan film coated on the endotracheal tube which can inhibit formation of bacterial biofilm effectively.Methods: The chitosan plastics were prepared and coated on the endotracheal tube with molecular weight of 5 000 and 1 000 000(in ratio of 2∶1),the filming effect and adhesion to endotracheal tube were investigated by in vitro study.E.colibio films of 7 days were established adopting the blank tubes, tubes coated chitosans with molecular weigh 5000 and 1000000 respectively, which arranged as the first and second group.Each group was carried out on bacterial counting, biofilm ration and observation under SEM respectively.Results: The adhesion time was 18d of the chitosan plastics in physiological environment.The bacterial quantity of group 1,2,were 2.29×107 CFU/ml, 1.19×107 CFU/ml respectively.The absorbency value of group 1,2 were 0.137,0.050 respectively.Under the circumstance of SEM, there were uniform and intensive bacteria on photograph of group 1.The bacterias had smooth cell wall, the regular body.There were few bacteria showing gathering state on photograph of group 2.The bacteria had sinking or scarred body.Conclusion: Film prepared by this method had good film forming properties, adhesion and inhibition on formation of bacterial biofilm.%目的:制备能有效抑制细菌生物被膜(BF)生成的壳聚糖气管导管涂膜.方法:以分子量5000和100万的壳聚糖为原料制备在气管导管内壁制膜(按2:1比例混合后涂膜),考察壳聚糖膜的成膜性、与气管导管的黏附性.以空白导管(对照组)和涂膜后的导管为载体,依次设为第1、2实验组,构建形成7d的大肠埃希菌生物被膜,然后细菌计数、生物被膜定量、扫描电镜(SEM)观察.结果:涂膜可紧密贴台在气管导管内壁,生理条件下与气管导管黏附时间为18d.对照组和实验组的细菌计数分别是2.29×10CFU/ml、1.19×10CFU/ml;吸光度为0.137、0.050;扫描电镜下,对照组的细菌密

  12. 壳聚糖涂层对Mg-6%Zn-10%Ca3(PO4)2植入材料生物相容性的影响%Effects of chitosan coating on biocompatibility of Mg-6%Zn-10%Ca3(PO4)2implant

    Institute of Scientific and Technical Information of China (English)

    赵俊; 陈良建; 余琨; 陈畅; 戴翌龙; 乔雪岩; 颜阳; 余志明

    2015-01-01

    研究壳聚糖包覆的Mg−6%Zn−10%Ca3(PO4)2植入材料生物体内的降解特性。采用0.2%的醋酸溶液溶解壳聚糖,将其在60°C下涂覆在复合材料样品表面,固化30 min得到壳聚糖的涂层。壳聚糖涂覆后的样品细胞毒性为0级,说明该涂层完全没有毒性,可以用于生物实验。生物体内实验表明:与无涂层的样品相比,植入涂覆有壳聚糖的复合材料后,在新西兰兔静脉血中的离子浓度较低。壳聚糖涂层可以减缓复合材料在生物体内的降解速率。生物体内实验表明,涂覆壳聚糖的复合材料对新西兰兔的重要器官,如心、肾、肝、肌肉都没有损伤,而新生骨组织会聚集在壳聚糖涂覆的复合材料周围,有利于骨组织的生长。壳聚糖涂层有利于减缓植入材料在生物体中的降解过程,减少氢气析出造成的皮下气泡产生,有利于提高复合材料的生物相容性。%A Mg−6%Zn−10%Ca3(PO4)2 composite with a chitosan coating was prepared to study its in vivo biodegradation properties. The chitosan dissolved in a 0.2% acetic acid solution was applied on the surface of Mg−6%Zn−10%Ca3(PO4)2 composite specimens and solidified at 60 °C for 30 min to form the coating. The cytotoxicity evaluation of chitosan coated specimens is at level 0, which indicates that such coating is safe for cellular applications. The in vivotests of chitosan coated composite show that the concentration of metal ions from the composite measured in the venous blood of Zelanian rabbits is less than that from the uncoated composite specimens. The chitosan coating impedes the in vivo degradation of the composite after surgery. The in vivo testing also indicates that the chitosan coated composite is harmless to important visceral organs, including the heart, kidneys and liver of the rabbits. The new bone formation surrounding the chitosan coated composite implant shows that the composite improves the

  13. Bioinspired, roughness-induced, water and oil super-philic and super-phobic coatings prepared by adaptable layer-by-layer technique

    Science.gov (United States)

    Brown, Philip S.; Bhushan, Bharat

    2015-01-01

    Coatings with specific surface wetting properties are of interest for anti-fouling, anti-fogging, anti-icing, self-cleaning, anti-smudge, and oil-water separation applications. Many previous bioinspired surfaces are of limited use due to a lack of mechanical durability. Here, a layer-by-layer technique is utilized to create coatings with four combinations of water and oil repellency and affinity. An adapted layer-by-layer approach is tailored to yield specific surface properties, resulting in a durable, functional coating. This technique provides necessary flexibility to improve substrate adhesion combined with desirable surface chemistry. Polyelectrolyte binder, SiO2 nanoparticles, and silane or fluorosurfactant layers are deposited, combining surface roughness and necessary chemistry to result in four different coatings: superhydrophilic/superoleophilic, superhydrophobic/superoleophilic, superhydrophobic/superoleophobic, and superhydrophilic/superoleophobic. The superoleophobic coatings display hexadecane contact angles >150° with tilt angles 160° with tilt angles oleophobic and hydrophobic properties, whilst others mix and match oil and water repellency and affinity. Coating durability was examined through the use of micro/macrowear experiments. These coatings display transparency acceptable for some applications. Fabrication via this novel combination of techniques results in durable, functional coatings displaying improved performance compared to existing work where either durability or functionality is compromised. PMID:26353971

  14. Effect of active edible coatings made by basil seed gum and thymol on oil uptake and oxidation in shrimp during deep-fat frying.

    Science.gov (United States)

    Khazaei, Naimeh; Esmaiili, Mohsen; Emam-Djomeh, Zahra

    2016-02-10

    The effect of active coating treatments on oil uptake, moisture loss, lipid oxidation, texture, color, and sensory evaluation of shrimp after deep-fat frying process was investigated. Compared with the uncoated samples, coating treatments decreased the oil uptake and moisture loss of fried shrimp by 34.50 and 13.9%, respectively. Fried shrimp samples were analyzed for peroxide value (PV) and thiobarbituric acid (TBA). The most reduction in lipid oxidation (46.4% for PV and 40.8% for TBA) was observed when shrimp samples were coated with CS4 (containing 10% thyme), while the control samples had the highest values of PV and TBA after deep-fat frying process. Coated fried samples had significantly lower toughness and stiffness than control samples (P0.05). However, for the texture, juiciness, chewiness, and overall acceptability, coated fried samples had higher scores than control.

  15. Fabrication and Wear Behavior Analysis on AlCrFeNi High Entropy Alloy Coating Under Dry Sliding and Oil Lubrication Test Conditions

    Science.gov (United States)

    Tang, Yipin; Wang, Shouren; Sun, Bin; Wang, Yan; Qiao, Yang

    2016-03-01

    In this paper, AlCrFeNi high entropy alloy coating was fabricated on the surface of Q235 steel using hot pressing sintering process. The coating has the controlled thickness size and excellent mechanical properties. Scanning electron microscopy (SEM), XRD and hardness testing method were used to study the morphology, phase structure and hardness of high entropy alloys coating. The lattice distortion plays a significant role in increasing the hardness. Coating formation mechanism caused by the element diffusion under the hot pressing effect is also discussed in the paper. Simultaneously, the dry sliding and oil lubrication wear tests, wear morphology observation and wear mechanism discussion were completed. As the result shows, AlCrFeNi high entropy alloys coating exhibits superior wear resistance either at dry sliding or oil lubrication tests owing to its hard high entropy solid solution structure.

  16. Vegetable-Oil-Based Hyperbranched Polyester-Styrene Copolymer Containing Silver Nanoparticle as Antimicrobial and Corrosion-Resistant Coating Materials

    Directory of Open Access Journals (Sweden)

    Manawwer Alam

    2013-01-01

    Full Text Available Pongamia oil (PO was converted to Pongamia oil hydroxyl (POH via epoxidation process. The esterification of POH with linolenic acid was carried out to form hyperbranched polyester (HBPE, and further styrenation was performed at the conjugated double bond in the chain of linolenic acid. After styrenation, silver nanoparticle was added in different weight percentages (0.1–0.4 wt%. The structural elucidation of POH, HBPE, and HBPE-St was carried out by FT-IR, 1H-NMR, and 13C-NMR spectroscopic techniques. Physicochemical and physicomechanical analyses were performed by standard method. Thermal behavior of the HBPE-St was analyzed by using thermogravimetric analysis (TGA and differential scanning calorimetry (DSC. The coatings of HBPE-St were prepared on mild steel strips. The anticorrosive behavior of HBPE-St resin-based coatings in acid, saline, and tap water was evaluated, and the molecular weight of HBPE-St was determined by gel permeation chromatography (GPC. The antibacterial activities of the HBPE-St copolymers were tested in vitro against bacteria and fungi by disc diffusion method. The HBPE-St copolymers exhibited good antibacterial activities and can be used as antimicrobial and corrosion-resistant coating materials.

  17. Effects of Chitosan, Lysozyme and Oregano Oil on Antimicrobial Activity of Soy Protein Isolate Film%壳聚糖、溶菌酶和牛至油对大豆分离蛋白膜抑菌效果的影响

    Institute of Scientific and Technical Information of China (English)

    杜会云; 赵寿经; 王新伟; 马中苏; 吴晓艳; 张艳平

    2011-01-01

    采用双倍稀释法研究壳聚糖、溶菌酶和牛至油对大肠杆菌和金黄色葡萄球菌的最小抑菌浓度.采用抑菌圈法研究添加天然抑菌剂壳聚糖、溶菌酶和牛至油的大豆分离蛋白膜对大肠杆菌、金黄色葡萄球菌、酿酒酵母和黑曲霉的抑菌效果.结果表明,添加壳聚糖、溶菌酶和牛至油的大豆分离蛋白膜对大肠杆菌、金黄色葡萄球菌、酿酒酵母和黑曲霉均有抑制作用.对大肠杆菌和金黄色葡萄球菌抑制效果为:牛至油>壳聚糖>溶菌酶.对酿酒酵母的抑制效果为:壳聚糖>牛至油>溶菌酶;对黑曲零的抑制效果为:牛至油>壳聚糖>溶菌酶.因此,添加壳聚糖、溶菌酶和牛至油的大豆分离蛋白膜具有较好的抑菌效果和应用前景.%Double dilution method was used to determine minimum inhibitory concentration of chitosan, lysozyme and oregano oil against Escherichia coli and Staphyloccocus aureus.Inhibition zone method was used to determine antimicrobial effect of soy protein isolate films enriched with chitosan, lysozyme and oregano oil against E.coli, S.aureus,Saccharomyces cerevisiae and Aspergillus niger.Results indicated that soy protein isolate films enriched with chitosan,lysozyme and oregano oil could inhibit the growth of E.coli, S.aureus, S.cerevisiae and A.niger.The inhibitory effect on E.coli and S.aureus: oregano oilchitosan > lysozyme.The inhibitory effect on S.cerevisiae: chitosan > oregano oil > lysozyme; the inhibitory effect on A.niger: oregano oilchitosan > lysozyme.This study showed the films enriched with chitosan, lysozyme and oregano oil have potential to be used as active biodegradable films with strong antimicrobial effects.

  18. Preparation of nano-TiO2/carboxymethyl chitosan compouded coatings and its application in antibacterial paper%纳米TiO2/羧甲基壳聚糖复合涂料的制备及其在抗菌纸中的应用

    Institute of Scientific and Technical Information of China (English)

    曹晓瑶; 黄元盛

    2015-01-01

    本文旨在探索能作为抗菌纸材料的优良品种。以纳米TiO2和实验室自制羧甲基壳聚糖为抗菌剂,制备了纳米TiO2/羧甲基壳聚糖复合涂料。利用FTIR对制备的羧甲基壳聚糖和复合涂料的基本结构进行了表征,并用MDS倒置金相显微镜对抗菌纸抗菌作用后的培养基形貌进行表征,对涂布抗菌纸的抗菌性能进行了研究。结果表明,纳米T i O2的加入能够提高羧甲基壳聚糖涂布抗菌纸的抑菌活性,而且当纳米T i O2和羧甲基壳聚糖的质量比为1.5∶1时,其涂料涂布后的抗菌纸抗菌率较高,达到86.5%。因此纳米T i O2和羧甲基壳聚糖二者互配可以作为抗菌纸的优良材料。%This paper aims to explore the good species used as antibacterial materials in antibacterial paper. Using nano-TiO2 and self-made carboxymethyl chitosan as the antimicrobial agent, the nano-TiO2/carboxymethyl chitosan compounded coating has been made. The basic structure of the self-made carboxymethyl chitosan and compouded coatings were characterized by FTIR. The morphology of the nutrient medium inlfuenced by the antibacterial effect of antibacterial paper were characterized by the MDS inverted microscope. The antibacterial properties of coated paper were studied. The results showed that the addition of nano-TiO2 can improve the antibacterial activity of antibacterial paper coated by carboxymethyl chitosan, furthermore, when the ratio of nanometer TiO2 and carboxymethyl chitosan is 1.5 to 1, the antibacterial rate of the coated antibacterial paper will be higher, reaching 86.5%. Therefore, nano-TiO2 and carboxymethyl chitosan matched mutually can be used as good materials in antibacterial paper.

  19. CORROSION RESISTANCE OF Fe–Al/Al2O3 DUPLEX COATING ON PIPELINE STEEL X80 IN SIMULATED OIL AND GAS WELL ENVIRONMENT

    OpenAIRE

    MIN HUANG; YU WANG; PING-GU WANG; QIN-YI SHI; MENG-XIAN ZHANG

    2015-01-01

    Corrosion resistant Fe–Al/Al2O3 duplex coating for pipeline steel X80 was prepared by a combined treatment of low-temperature aluminizing and micro-arc oxidation (MAO). Phase composition and microstructure of mono-layer Fe–Al coating and Fe–Al/Al2O3 duplex coating were studied by X-ray diffraction (XRD), scanning electron microscope (SEM) with energy dispersive spectrometer (EDS). Corrosion resistance of the coated pipeline steel X80 in a simulated oil and gas well condition was also investig...

  20. of Clove on Physicochemical Properties of Chitosan-Based Films

    Directory of Open Access Journals (Sweden)

    Paola Reyes-Chaparro

    2015-01-01

    Full Text Available Mechanical and barrier properties of chitosan films prepared with essential oils of clove and functional extract were studied. The films made with functional extracts (esters E6 and E7 presented the significant increment of extensibility compared with the untreated chitosan films. In the case of punction test, the films made with the esters E6 and E7 resisted more the applied strength before tearing up compared with the chitosan control film (without any treatment. Thermogravimetric analysis values were determined for the chitosan control film and chitosan film treated with clove essential oil obtaining 112.17°C and 176.73°C, respectively. Atomic force microscopy (AFM was used to determine their morphology by analyzing their surfaces and phase arrangement; AFM was also used to observe the porosity in chitosan-based antimicrobial films and the chitosan films incorporating functional extracts. The water vapour permeability (WVP data showed that incorporating the functional extract to the formulation of films has a positive effect on water vapour barrier properties. In general, the incorporation of essential oils and functional extract of clove at 20% in chitosan films caused microstructural changes that were dependent on the different affinity of components.

  1. Properties of emulsions stabilised by sodium caseinate–chitosan complexes

    NARCIS (Netherlands)

    Zinoviadou, K.; Scholten, E.; Moschakis, T.; Biliaderis, C.G.

    2012-01-01

    Oil-in-water emulsions (10%, w/w, oil) were prepared at pH 5.7 by using electrostatically formed complexes of 0.5% (w/w) sodium caseinate (Na-CAS) and 0–0.6% (w/w) chitosan. Emulsions stabilized by complexes with increased levels of chitosan (>0.2% w/w) had a smaller average droplet size and exhi

  2. Effect of nano-composite and Thyme oil (Tymus Vulgaris L) coating on fruit quality of sweet cherry (Takdaneh Cv) during storage period

    OpenAIRE

    Nabifarkhani, Naser; Sharifani, Mehdi; Daraei Garmakhany, Amir; Ganji Moghadam, Ebrahim; Shakeri, Alireza

    2015-01-01

    Sweet cherry is one of the most appreciated fruit by consumers since it is an early season fruit and has an excellent quality. In this study effect of active nano composite formed from chitosan (as a matrix material), nano cellulose fiber (1% concentration) and Thyme oils (Tymus Vulgaris L) at 1% concentration on fruits quality was investigated. Treated fruits were stored at 1°C for 5 weeks and changes of different qualities attributes including weight loss, total acidity, TSS, anthocyanin, t...

  3. Reactive coating of soybean oil-based polymer on nanofibrillated cellulose film for water vapor barrier packaging.

    Science.gov (United States)

    Lu, Peng; Xiao, Huining; Zhang, Weiwei; Gong, Glen

    2014-10-13

    Nanofibrillated cellulose (NFC) easily forms a high strength film but is unable to withstand the influence of water vapor when used in high moisture situations. The water vapor transmission rate (WVTR) of a NFC film was as high as 5088 g/m(2)24h (38 °C, 90% RH). The addition of beeswax latex in a NFC casting film (NFX) lowered the WVTR to 3918 g/m(2)24h. To further reduce the WVTR, a coating agent comprised of acrylated epoxidized soybean oil (AESO) and 3-aminopropyltriethoxysilane (APTS) was applied onto the NFX film using a rod coater. A combination of the suitable AESO/APTS ratio, initiator dosing, curing time and temperature could reduce the WVTR to 188 g/m(2) 24h when the coat weight was 5 g/m(2). Moreover, the coated NFX film was highly hydrophobic along with the improved transparency and thermal stability. This biodegradable polymer-coated NFC film can be used as potential packaging barrier in certain areas.

  4. PENGARUH MINYAK ATSIRI JAHE MERAH DAN LENGKUAS MERAH PADA EDIBLE COATING TERHADAP KUALITAS FILLET IKAN PATIN (Effect of Edible Coating Enriched with Red Ginger and Red Galangal Essential Oil on the Quality of Patin Fillet

    Directory of Open Access Journals (Sweden)

    Rohula Utami

    2014-02-01

    edible coating will retain the patin fillets quality. In terms of microbial quality and TVB value, 1% essential oil of red ginger and red galangal enrichment in edible coating could extend shelf life of patin fillets for 2-4 days. Keywords: Edible coating, essential oil, patin, red ginger, red galangal   ABSTRAK Penentuan pengaruh penambahan minyak atsiri jahe merah dan lengkuas merah dalam edible coating terhadap kualitas fillet ikan patin selama penyimpanan dingin dilakukan pada periode waktu 8 hari. Parameter kualitas ikan yang dianalisis adalah kualitas mikrobiologis (Total Plate Count/TPc, dan kualitas fisikokimia (Total Volatile Bases/TVB, Thiobarbituricacid/TBa, pH, dan warna. Variasi perlakuan fillet ikan patin yaitu konsentrasi minyak atsiri (0 %; 0,1%; 1% yang ditambahkan dalam edible coating. Hasil penelitian ini mengindikasikan bahwa penambahan minyak atsiri baik jahe merah maupun lengkuas merah berpengaruh terhadap kualitas fillet ikan patin selama penyimpanan dingin. Penambahan minyak atsiri dalam edible coating mampu mempertahankan kualitas fillet ikan patin lebih baik dibandingkan perlakuan edible coating tanpa minyak atsiri. Berdasarkan kualitas mikrobiologis dan nilai TVB, perlakuan minyak atsiri jahe merah 1% dan minyak atsiri lengkuas merah 1% mampu meningkatkan umur simpan fillet ikan patin selama 2-4 hari. Kata kunci: Edible coating, jahe merah, lengkuas merah, minyak atsiri, patin

  5. Effects of Chitosan on the Shelf Life of Harbin Red-sausage

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Chitosan and Chitin can inhibit the growth of bacteria. The effect of different concentrations of chitosan solutions on the shelf life of Harbin Red-sausage was studied in this paper. Dipping the Red-sausage with chitosan could extend the shelf life significantly. The optimal composition of coating solution was 3% chitosan solution, whose deacetylated rate was 94%, which was dissolved in 2% acetic acid solution. The CFUs of the sausages with the chitosan deacetylated rate 94% treatment were significantly lower than control at the whole storage (P <0.05).

  6. Coated carbide drill performance under soluble coconut oil lubricant and nanoparticle enhanced MQL in drilling AISI P20

    Science.gov (United States)

    Jamil, N. A. M.; Azmi, A. I.; Fairuz, M. A.

    2016-02-01

    This research experimentally investigates the performance of a TiAlN coated carbide drill bit in drilling AISI P20 through two different kinds of lubricants, namely; soluble coconut oil (SCO) and nanoparticle-enhanced coconut oil (NECO) under minimum quantity lubrication system. The tool life and tool wear mechanism were studied using various cutting speeds of 50, 100 and 150 m/min with a constant feed of 0.01 mm/rev. Since the flank wear land was not regular along the cutting edge, the average flank wear (VB) was measured at several points using image analysis software. The drills were inspected using a scanning electron microscope to further elucidate the wear mechanism. The result indicates that drilling with the nanoparticle- enhanced lubricant was better in resisting the wear and improving the drill life to some extent

  7. HYDROXYAPATITE/CHITOSAN COMPOSITE COATINGS ON TITANIUM SURFACES BY PULSED ELECTROCHEMICAL DEPOSITION%脉冲电化学沉积法制备羟基磷灰石/壳聚糖复合涂层的研究

    Institute of Scientific and Technical Information of China (English)

    王英波; 鲁雄; 李丹; 冯波; 屈树新; 翁杰

    2011-01-01

    A pulsed electrochemical deposition (ED) method was employed to produce hydroxyapatite ( HA )/ chitosan(CS) composite coatings on Ti substrates. HA dispersed uniformly in the CS network. There was nano-scale hybridization between HA and CS due to in situ co-precipitation. ED was conducted in the cell that had three electrodes: a Ti plate as the working electrode, a platinum plate as the counter electrode and a saturated calomel electrode ( SCE) as the reference electrode. Electrolytes were aqueous solution of 5 mmol/L Ca(NO3)2,3 mmol/L (NH4)2HPO4 and CS aqueous solutions with different concentrations (0. 17 g/L,0. 33 g/L,0. 67 g/L). The coatings were prepared under constant voltage and pulsed voltage modes. The experiment results indicated that the pulsed voltage mode can improve the CS content in the coatings and obtain uniform coatings, compared with the constant voltage mode. The pulsed voltage mode also promoted the interaction between Ca and CS according to XPS analysis. Pulsed voltage affected the morphology of the coatings and improved the efficiency of the deposition. The suitable pulsed voltage was -1.3 V. The concentration of CS in the electrolyte affected the CS content in the coatings and the efficiency of the deposition. The suitable concentration was 33. 1 g/L. The antibacterial test indicated that HA/CS coatings had good bactericidal ability. Osteoblasts were cultured on the coatings to evaluate the biocompatibility of coatings and the results indicated that the composite coatings favored the attachment and proliferation of the osteoblasts. The results of present study provided valuable references for the further research in developing composite coatings for biomedical applications.%采用脉冲电化学沉积法在钛金属表面制备出羟基磷灰石/壳聚糖(HA/CS)复合涂层,实现CS与HA在微观尺寸上的复合与杂化.比较了脉冲电位与恒电位模式下复合涂层的形成,研究了电位高低及壳聚糖浓度对复合涂层

  8. Chitosan functional properties.

    Science.gov (United States)

    Shepherd, R; Reader, S; Falshaw, A

    1997-06-01

    Chitosan is a partially deacetylated polymer of N-acetyl glucosamine. It is essentially a natural, water-soluble, derivative of cellulose with unique properties. Chitosan is usually prepared from chitin (2 acetamido-2-deoxy beta-1,4-D-glucan) and chitin has been found in a wide range of natural sources (crustaceans, fungi, insects, annelids, molluscs, coelenterata etc.) However chitosan is only manufactured from crustaceans (crab and crayfish) primarily because a large amount of the crustacean exoskeleton is available as a by product of food processing. Squid pens (a waste byproduct of New Zealand squid processing) are a novel, renewable source of chitin and chitosan. Squid pens are currently regarded as waste and so the raw material is relatively cheap. This study was intended to assess the functional properties of squid pen chitosan. Chitosan was extracted from squid pens and assessed for composition, rheology, flocculation, film formation and antimicrobial properties. Crustacean chitosans were also assessed for comparison. Squid chitosan was colourless, had a low ash content and had significantly improved thickening and suspending properties. The flocculation capacity of squid chitosan was low in comparison with the crustacean sourced chitosans. However it should be possible to increase the flocculation capacity of squid pen chitosan by decreasing the degree of acetylation. Films made with squid chitosan were more elastic than crustacean chitosan with improved functional properties. This high quality chitosan could prove particularly suitable for medical/analytical applications.

  9. Environmental applications of chitosan and its derivatives.

    Science.gov (United States)

    Yong, Soon Kong; Shrivastava, Manoj; Srivastava, Prashant; Kunhikrishnan, Anitha; Bolan, Nanthi

    2015-01-01

    , hydraulic conductivity, permeability, surface area and sorption capacity. Crosslinked chitosan is an excellent sorbent for trace metals especially because of the high flexibility of its structural stability. Sorption of trace metals by chitosan is selective and independent of the size and hardness of metal ions, or the physical form of chitosan (e.g., film, powder and solution). Both -OH and -NH2 groups in chitosan provide vital binding sites for complexing metal cations. At low pH, -NH3 + groups attract and coagulate negatively charged contaminants such as metal oxyanions, humic acids and dye molecules. Grafting certain functional molecules into the chitin structure improves sorption capacity and selectivity for remediating specific metal ions. For example, introducing sulfur and nitrogen donor ligands to chitosan alters the sorption preference for metals. Low molecular weight chitosan derivatives have been used to remediate metal contaminated soil and sediments. They have also been applied in permeable reactive barriers to remediate metals in soil and groundwater. Both chitosan and modified chitosan have been used to phytoremediate metals; however, the mechanisms by which they assist in mobilizing metals are not yet well understood. In addition, microbes have been used in combination with chitosan to remediate metals (e.g., Cu and Zn) in contaminated soils. Chitosan has also been used to remediate organic contaminants, such as oil-based wastewater, dyes, tannins, humic acids, phenols, bisphenoi-A, p-benzoquinone, organo-phosphorus insecticides, among others. Chitosan has also been utilized to develop optical and electrochemical sensors for in-situ detection of trace contaminants. In sensor technology, naturally-derived chitosan is used primarily as an immobilizing agent that results from its enzyme compatibility, and stabilizing effect on nanoparticles. Contaminant-sensing agents, such as enzymes, microbes and nanoparticles, have been homogeneously immobilized in chitosan

  10. Composite Coatings with Ceramic Matrix Including Nanomaterials as Solid Lubricants for Oil-Less Automotive Applications

    Directory of Open Access Journals (Sweden)

    Posmyk A.

    2016-06-01

    Full Text Available The paper presents the theoretical basis of manufacturing and chosen applications of composite coatings with ceramic matrix containing nanomaterials as a solid lubricant (AHC+NL. From a theoretical point of view, in order to reduce the friction coefficient of sliding contacts, two materials are required, i.e. one with a high hardness and the other with low shear strength. In case of composite coatings AHC+NL the matrix is a very hard and wear resistant anodic oxide coating (AHC whereas the solid lubricant used is the nanomaterial (NL featuring a low shear strength such as glassy carbon nanotubes (GC. Friction coefficient of cast iron GJL-350 sliding against the coating itself is much higher (0.18-0.22 than when it slides against a composite coating (0.08-0.14. It is possible to reduce the friction due to the presence of carbon nanotubes, or metal nanowires.

  11. Corrosion behavior of Fe-Si metallic coatings added with NiCrAlY in an environment of fuel oil ashes at 700 C

    Energy Technology Data Exchange (ETDEWEB)

    Salinas-Bravo, V.M.; Porcayo-Calderon, J.; Romero-Castanon, T. [Instituto de Investigaciones Electricas, Gerencia de Procesos Termicos., Av. Reforma 113, C.P. 62490 Col. Palmira. Temixco. Morelos (Mexico); Dominguez-Patino, G.; Gonzalez-Rodriguez, J.G. [U.A.E.M. Centro de Investigaciones en Ingenieria y Ciencias Aplicadas., Av. Universidad 1001, C.P. 62210, Col. Chamilpa. Cuernavaca, Morelos (Mexico)

    2005-07-01

    Electrochemical potentiodynamic polarization curves and immersion tests for 300 h at 700 C in a furnace have been used to evaluate the corrosion resistance of Fe-Si metallic coatings added with up to 50 wt.% of NiCrAIY. The corrosive environment was fuel oil ashes from a steam generator. The composition of fuel oil ashes includes high content of vanadium, sodium and sulfur. The results obtained show that only the addition of 20 wt.% NiCrAlY to the Fe-Si coating improves its corrosion resistance. The behavior of all tested coatings is explained by the results obtained from the analysis of every coating using electron microscopy and energy dispersive X-ray analysis. (Abstract Copyright [2005], Wiley Periodicals, Inc.)

  12. Clinical value of chitosan antimicrobial coating for cervical lesions after physical therapy%宫颈病变物理治疗后应用壳聚糖抗菌膜的临床价值分析

    Institute of Scientific and Technical Information of China (English)

    董翠莉; 曾定元

    2013-01-01

    目的 观察宫颈病变物理治疗后应用壳聚糖抗菌膜的临床疗效.方法 将接受激光治疗的单纯重度宫颈糜烂患者200例随机分为A、B组,每组100例;再将接受宫颈环形电切术(LEEP)或包括冷刀锥切(CKC)治疗的CIN患者100例随机分为C、D组,每组50例.A、C组患者术后接受壳聚糖宫颈抗菌膜辅助治疗.比较4组患者阴道排液量、排液时间、出血量、出血时间以及宫颈愈合情况.结果 A组阴道排液量和出血量均显著少于B组,阴道排液时间及出血时间均显著短于B组,治愈与显效率显著高于B组;C组阴道流血及排液持续时间显著短于D组,C、D组阴道出血量、排液量、创面愈合情况无显著差异.结论 物理治疗后联合应用壳聚糖宫颈抗菌膜可减少创面渗出及出血,提高创面愈合率,减轻患者痛苦,提高生活质量.%Objective To observe the clinical effects of chitosan antimicrobial coating in the treatment of cervical lesions after physical therapy.Methods Two hundred patients with simple severe cervical erosion treated with laser were randomly divided into groups A and B,100 cases in each group.Another 100 patients with cervical intraepithelial neoplasia (CIN) treated with loop electrosurgical excision procedure (LEEP) or cold knife conization (CKC) were randomly divided into groups C and D,50 cases in each group.The patients in groups A and C after operation received the adjuvant therapy of chitosan antimicrobial coating.The amount and time of vaginal discharge,bleeding amount and time as well as conditions of cervical healing were compared in four groups.Results The amounts of vaginal discharge and bleeding in group A were both less than those in group B significantly,times of vaginal discharge and bleeding obviously shorter than group B,and cure and effectiveness rates conspicuously higher than group B,all differences had statistical significance.Vaginal bleeding and discharge time in group C were

  13. Cytotoxicity and intracellular fate of PLGA and chitosan-coated PLGA nanoparticles in Madin-Darby bovine kidney (MDBK) and human colorectal adenocarcinoma (Colo 205) cells.

    Science.gov (United States)

    Trif, Mihaela; Florian, Paula E; Roseanu, Anca; Moisei, Magdalena; Craciunescu, Oana; Astete, Carlos E; Sabliov, Cristina M

    2015-11-01

    Polymeric nanoparticles (NPs) are known to facilitate intracellular uptake of drugs to improve their efficacy, with minimum bioreactivity. The goal of this study was to assess cellular uptake and trafficking of PLGA NPs and chitosan (Chi)-covered PLGA NPs in Madin-Darby bovine kidney (MDBK) and human colorectal adenocarcinoma (Colo 205) cells. Both PLGA and Chi-PLGA NPs were not cytotoxic to the studied cells at concentrations up to 2500 μg/mL. The positive charge conferred by the chitosan deposition on the PLGA NPs improved NPs uptake by MDBK cells. In this cell line, Chi-PLGA NPs colocalized partially with early endosomes compartment and showed a more consistent perinuclear localization than PLGA NPs. Kinetic uptake of PLGA NPs by Colo 205 was slower than that by MDBK cells, detected only at 24 h, exceeding that of Chi-PLGA NPs. This study offers new insights on NP interaction with target cells supporting the use of NPs as novel nutraceuticals/drug delivery systems in metabolic disorders or cancer therapy. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 3599-3611, 2015.

  14. Design and construction of polymerized-chitosan coated Fe3O4 magnetic nanoparticles and its application for hydrophobic drug delivery.

    Science.gov (United States)

    Ding, Yongling; Shen, Shirley Z; Sun, Huadong; Sun, Kangning; Liu, Futian; Qi, Yushi; Yan, Jun

    2015-03-01

    In this study, a novel hydrogel, chitosan (CS) crosslinked carboxymethyl-β-cyclodextrin (CM-β-CD) polymer modified Fe3O4 magnetic nanoparticles was synthesized for delivering hydrophobic anticancer drug 5-fluorouracil (CS-CDpoly-MNPs). Carboxymethyl-β-cyclodextrin being grafted on the Fe3O4 nanoparticles (CDpoly-MNPs) contributed to an enhancement of adsorption capacities because of the inclusion abilities of its hydrophobic cavity with insoluble anticancer drugs through host-guest interactions. Experimental results indicated that the amounts of crosslinking agent and bonding times played a crucial role in determining morphology features of the hybrid nanocarriers. The nanocarriers exhibited a high loading efficiency (44.7±1.8%) with a high saturation magnetization of 43.8emu/g. UV-Vis spectroscopy results showed that anticancer drug 5-fluorouracil (5-Fu) could be successfully included into the cavities of the covalently linked CDpoly-MNPs. Moreover, the free carboxymethyl groups could enhance the bonding interactions between the covalently linked CDpoly-MNPs and anticancer drugs. In vitro release studies revealed that the release behaviors of CS-CDpoly-MNPs carriers were pH dependent and demonstrated a swelling and diffusion controlled release. A lower pH value led to swelling effect and electrostatic repulsion contributing to the protonation amine impact of NH3(+), and thus resulted in a higher release rate of 5-Fu. The mechanism of 5-Fu encapsulated into the magnetic chitosan nanoparticles was tentatively proposed.

  15. A novel preparation method for silicone oil nanoemulsions and its application for coating hair with silicone

    Directory of Open Access Journals (Sweden)

    Hu Z

    2012-11-01

    Full Text Available Zhenhua Hu,1,2,* Meiling Liao,2,* Yinghui Chen,3,* Yunpeng Cai,2 Lele Meng,2 Yajun Liu,2 Nan Lv,2 Zhenguo Liu,1 Weien Yuan21Department of Neurology, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China; 2School of Pharmacy, Shanghai Jiao Tong University, Shanghai, People's Republic of China; 3Department of Neurology, Jinshan Hospital, Fudan University, Jinshan District, Shanghai, People's Republic of China*These authors contributed equally to this workBackground: Silicone oil, as a major component in conditioner, is beneficial in the moisture preservation and lubrication of hair. However, it is difficult for silicone oil to directly absorb on the hair surface because of its hydrophobicity. Stable nanoemulsions containing silicone oil may present as a potential solution to this problem.Methods: Silicone oil nanoemulsions were prepared using the oil-in-water method with nonionic surfactants. Emulsion particle size and distribution were characterized by scanning electron microscopy. The kinetic stability of this nanoemulsion system was investigated under accelerated stability tests and long-term storage. The effect of silicone oil deposition on hair was examined by analyzing the element of hair after treatment of silicone oil nanoemulsions.Results: Nonionic surfactants such as Span 80 and Tween 80 are suitable emulsifiers to prepare oil-in-water nanoemulsions that are both thermodynamically stable and can enhance the absorption of silicone oil on hair surface.Conclusion: The silicone oil-in-water nanoemulsions containing nonionic surfactants present as a promising solution to improve the silicone oil deposition on the hair surface for hair care applications.Keywords: silicone oil, nanoemulsion, stability, moisture preservation, lubrication

  16. Determination of physical properties for β-TCP + chitosan biomaterial obtained on metallic 316L substrates

    Energy Technology Data Exchange (ETDEWEB)

    Mina, A. [Tribology, Powder Metallurgy and Processing of Solid Recycled Research Group, Universidad del Valle, Cali (Colombia); Tecno-Academia ASTIN SENA Reginal Valle (Colombia); Castaño, A. [Tribology, Powder Metallurgy and Processing of Solid Recycled Research Group, Universidad del Valle, Cali (Colombia); Caicedo, J.C., E-mail: julio.cesar.caicedo@correo.univalle.edu.co [Tribology, Powder Metallurgy and Processing of Solid Recycled Research Group, Universidad del Valle, Cali (Colombia); Caicedo, H.H. [Biologics Research, Biotechnology Center of Excellence, Janssen R& D, LLC, Pharmaceutical Companies of Johnson & Johnson, Spring House, PA 19477 (United States); National Biotechnology & Pharmaceutical Association, Chicago, IL 60606 (United States); Aguilar, Y. [Tribology, Powder Metallurgy and Processing of Solid Recycled Research Group, Universidad del Valle, Cali (Colombia)

    2015-06-15

    Material surface modification, particularly the deposition of special coatings on the surface of surgical implants, is extensively used in bone tissue engineering applications. β-Tricalcium phosphate/Chitosan (β-TCP/Ch) coatings were deposited on 316L stainless steel (316L SS) substrates by a cathodic electro-deposition technique at different coating compositions. The crystal lattice arrangements were analyzed by X-Ray diffraction (XRD), and the results indicated that the crystallographic structure of β-TCP was affected by the inclusion of the chitosan content. The changes in the surface morphology as a function of increasing chitosan in the coatings via scanning electron microscopy (SEM) and atomic force microscopy (AFM) showed that root-mean square values of the β-TCP/Ch coatings decreased by further increasing chitosan percentage. The elastic–plastic characteristics of the coatings were determined by conducting nanoindentation test, indicating that increase of chitosan percentage is directly related to increase of hardness and elastic modulus of the β-TCP/Ch coatings. Tribological characterization was performed by scratch test and pin-on-disk test to analyze the changes in the surface wear of β-TCP/Ch coatings. Finally, the results indicated an improvement in the mechanical and tribological properties of the β-TCP/Ch coatings as a function of increasing of the chitosan percentage. This new class of coatings, comprising the bioactive components, is expected not only to enhance the bioactivity and biocompatibility, but also to protect the surface of metallic implants against wear and corrosion. - Highlights: • Superficial phenomenon that occurs in tribological surface of β-tricalcium phosphate-chitosan coatings. • Improvement on surface mechanical properties of ceramic-polymeric and response to surface tribological damage. • β-tricalcium phosphate-chitosan coatings that offer highest performance in the biomedical devices.

  17. EFFECT OF MAGNETRON-SPUTTERED Al FILM ON LOW-TEMPERATURE PACK-ALUMINIZING COATING FOR OIL CASING STEEL N80

    OpenAIRE

    MIN HUANG; YU WANG; MENG-XIAN ZHANG; YAN-QIU HUO; PENG-JIN GAO

    2014-01-01

    Low-temperature aluminizing coating was prepared onto the surface of oil casing steel N80 with a magnetron-sputtered Al film to improve its corrosion resistance. Results show that magnetron-sputtered Al film is able to form gradient aluminide coating, composed of iron aluminide FeAl3, Fe2Al5 and Fe3Al with different contents of aluminum. Both the density and continuity of iron aluminide layer for oil casing steel N80 with magnetron-sputtered Al film can be improved. Under the same corrosion c...

  18. Preparation of cross-linked lipase-coated micro-crystals for biodiesel production from waste cooking oil.

    Science.gov (United States)

    Yan, Jinyong; Yan, Yunjun; Liu, Sanxiong; Hu, Jiang; Wang, Guilong

    2011-04-01

    A dual modification procedure composed of cross-linking and protein coating with K(2)SO(4) was employed to modify Geotrichum sp. lipase for catalyzing biodiesel production from waste cooking oil. Compared to single modification of protein coating with K(2)SO(4), the dual modification of cross-linking and lipase coating improved catalytic properties in terms of thermostable stability, organic solvent tolerance, pH stability and operational stability in biodiesel production process, although biodiesel yield and initial reaction rate for CLPCMCs were not improved. After five successive batch reactions, CLPCMCs could still maintain 80% of relative biodiesel yield. CLPCMCs retained 64% of relative biodiesel yield after incubation in a pH range of 4-6 for 4 h, and 85% of relative biodiesel yield after incubation in a range of 45-50 °C for 4 h. CLPCMCs still maintained 83% of relative biodiesel yield after both treated in polar organic solvent and non-polar organic solvent for 4 h.

  19. Photoelectrochemical Solar Cells Based on Chitosan Electroylte

    Institute of Scientific and Technical Information of China (English)

    M.H.A.Buraidah; A.K.Arof

    2007-01-01

    1 Results ITO-ZnTe/Chitosan-NH4I-I2/ITO photoelectrochemical solar cells have been fabricated and characterized by current-voltage characteristics.In this work,the ZnTe thin film was prepared by electrodeposition on indium-tin-oxide coated glass.The chitosan electrolyte consists of NH4I salt and iodine.Iodine was added to provide the I3-/I- redox couple.The PEC solar cell was fabricated by sandwiching an electrolyte film between the ZnTe semiconductor and ITO conducting glass.The area of the solar cell...

  20. Multilayered silicone oil droplets of narrow size distribution: preparation and improved deposition on hair.

    Science.gov (United States)

    Nazir, Habiba; Wang, Lianyan; Lian, Guoping; Zhu, Shiping; Zhang, Yueling; Liu, Yuan; Ma, Guanghui

    2012-12-01

    Silicone oil droplets have limited deposition on hair due to electrostatic repulsion with negative surface charge of hair substrates. Aiming to improve silicone deposition on hair substrates, surface properties of uniform-sized silicone oil droplets (produced by membrane emulsification) were modified using layer-by-layer electrostatic deposition. By using this method, silicone oil droplets were coated with large molecular weight polymers, i.e. quaternized chitosan and alginate, and low molecular weight compounds, i.e. diallyl dimethyl ammonium chloride and glycerol to obtain six alternate layers of different surface charges. It was found that the dispersion of coated silicone oil droplets of narrow size distribution exhibited much improved mechanical strength and increased viscosity against shear compared to uncoated droplets. These multilayered silicone oil droplets were then added into model shampoos and conditioners to study the effect of charge and molecular weight of coating materials on silicone oil deposition on hair. The results clearly demonstrated that surface charge and charge density have significant influence on silicone oil deposition. Droplets with higher positive charge density resulted in increased deposition of silicone on hair due to electrostatic attraction. Characterization of the hair surface potential, wetting properties and friction certified the results further, showing reduced friction, decreased wetting angle and positive surface potential of high density positively charged silicone oil droplets. Therefore, LBL surface modification combined with membrane emulsification is a promising method for preparing multilayered silicone oil droplets of increased mechanical strength, viscosity and deposition on hair.

  1. On Hydrolysis of Olive Oil by Immobilized Lipase on Chitosan/Bentonite Carrier%壳聚糖/膨润土固定化脂肪酶水解橄榄油的研究

    Institute of Scientific and Technical Information of China (English)

    曹婕; 董华平

    2016-01-01

    In order to solve the low catalytic stability, difficult recovery and other issues of free lipase, we tried to choose the different ratio of chitosan/bentonite as the carrier of lipase to improve its activity in the hydrolysis of olive oil. The chitosan/bentonite composites were characterized by Fourier Transform Infrared Spectroscopy ( FT-IR) and Scanning Electron Microscopy ( SEM) , and the catalytic properties of immobilization lipases on various chitosan/bentonite in the hydrolysis of olive oil were studied. The results show that 10% of the mass ratio of chi-tosan and bentonite (CB-10) can achieve the best immobilization yield of lipase (92. 1%) on the carrier, and the catalytic activity of the immobilized enzyme is 0. 56U/mg. The residual activity of the immobilized enzyme is 68. 2% after 5 consecutive batches of the reaction, showing good catalytic stability. The research findings indi-cate that the chitosan/bentonite composite which can make a better balance between the structural rigidity of the inorganic material and the biocompatibility of the natural polymer material is a good carrier of the immobilized en-zyme.%为了改善游离脂肪酶催化稳定性低、难以回收等缺陷,以不同比例的壳聚糖/膨润土复合载体负载脂肪酶,以提高脂肪酶在橄榄油水解中的催化性能.通过红外光谱( FTIR)、扫描电镜( SEM)等对壳聚糖/膨润土复合材料进行表征,并考察了各种壳聚糖/膨润土固定化脂肪酶对橄榄油水解反应的催化性能.结果表明:当壳聚糖与膨润土的质量比为10%( CB-10)时,脂肪酶的负载量达到最高(92.1%),固定化酶的催化活性为0.56 U/mg,连续反应5批次后,固定化酶的剩余活性为初始值的68.2%,显示了较好的催化稳定性.该研究结果说明,壳聚糖/膨润土复合材料较好地兼顾了无机材料的结构刚性和天然高分子物质的生物相容性,是固定化酶的良好载体.

  2. The Friction and Wear Properties of CrN, Graphit-iC and Dymon-iC Coatings in Air and under Oil-lubrication.

    Institute of Scientific and Technical Information of China (English)

    J. Stallard; S. Yang; D.G. Teer

    2004-01-01

    Hard ceramic coatings such as TiN and CrN are very successful and are widely used in improving the performance of cutting and forming tools, but they are less successful in providing protection for general machine components, such as gears and engine parts. The development of low-friction wear resistant coatings that can run dry or in a minimum amount of oil is becoming increasingly important to this industry. Two recently developed carbon-based coatings Graphit-iCTM and Dymon-iC, which are shown to exhibit very high sliding wear resistance and low friction in dry conditions, are compared to a CrN coating under oil lubricated conditions. Long term pin-on-disc tests using a chrome steel counterface ball were carried out on coated HSS test samples. All the coatings performed well at very high applied contact pressures, exceeding 1.5 GPa, but the Graphit-iCTM and Dymon-iC coatings also exhibited the desirable characteristic of protecting the counterface material. Reasons for this behaviour are discussed.

  3. Antioxidant and antibacterial activities of eugenol and carvacrol-grafted chitosan nanoparticles.

    Science.gov (United States)

    Chen, Fei; Shi, Zhilong; Neoh, K G; Kang, E T

    2009-09-01

    Essential oils are known to possess antimicrobial and antioxidant activity while chitosan is a biocompatible polymer with antibacterial activity against a broad spectrum of bacteria. In this work, nanoparticles with both antioxidant and antibacterial properties were prepared by grafting eugenol and carvacrol (two components of essential oils) on chitosan nanoparticles. Aldehyde groups were first introduced in eugenol and carvacrol, and the grafting of these oils to chitosan nanoparticles was carried out via the Schiff base reaction. The surface concentration of the grafted essential oil components was determined by X-ray photoelectron spectroscopy (XPS). The antioxidant activities of the carvacrol-grafted chitosan nanoparticles (CHCA NPs) and the eugenol-grafted chitosan nanoparticles (CHEU NPs) were assayed with diphenylpicrylhydrazyl (DPPH). Antibacterial assays were carried out with a representative gram-negative bacterium, Escherichia coli (E. coli) and a gram-positive bacterium, Staphylococcus aureus (S. aureus). The grafted eugenol and carvacrol conferred antioxidant activity to the chitosan nanoparticles, and the essential oil component-grafted chitosan nanoparticles achieved an antibacterial activity equivalent to or better than that of the unmodified chitosan nanoparticles. Cytotoxicity assays using 3T3 mouse fibroblast showed that the cytotoxicity of CHEU NPs and CHCA NPs were significant lower than those of the pure essential oils.

  4. Surface and Wear Analysis of Zinc Phosphate Coated Engine Oil Ring and Cylinder Liner Tested with Commercial Lubricant

    Directory of Open Access Journals (Sweden)

    Doğuş Özkan

    2014-09-01

    Full Text Available The objective of this study was to evaluate the tribological performance through investigating protective additive layer and friction coefficient and implementing the quantitative wear measurements on the rubbed surface of the sliding pairs. The specimens of oil ring were rubbed against cast iron engine cylinder liner under boundary lubrication conditions. The ring and liner surfaces were examined by optical, scanning electron microscope and atomic force microscopy. The elemental analysis of surfaces was performed by using energy dispersive X-ray spectroscopy. Surface observations showed that coating was removed from the ring surface. Higher levels of Ca, Zn, P, and S elemental ratios (0.93%, 0.45%, 1.55%, and 1.60% as atomic percent were detected on the cylinder liner surface. Wear width, length, and depth measurements were performed by optical and atomic force microscopies on the ring and cylinder liner surface. The results showed that wear widths for oil ring were 1.59 μm and 1.65 μm; wear widths for cylinder liner were 3.20 μm and 3.18 μm; wear depths for oil ring were 100 nm; and wear depths for cylinder liner were 482 nm. Wear data were taken mostly from the additive layer points detected by SEM and X-ray measurements.

  5. Novel procedure to enhance PLA surface properties by chitosan irreversible immobilization

    Energy Technology Data Exchange (ETDEWEB)

    Stoleru, Elena; Dumitriu, Raluca Petronela [Petru Poni Institute of Macromolecular Chemistry, Grigore Ghica Voda Alley, 41A, 700487 Iasi (Romania); Munteanu, Bogdanel Silvestru [“Al. I. Cuza” University, Faculty of Physics, 11 Carol I Blvd., 700506 Iasi (Romania); Zaharescu, Traian [INCDIE ICPE CA, Bucharest (Romania); Tănase, Elisabeta Elena; Mitelut, Amalia [Industrial Biotechnology Department, Faculty of Biotechnolog