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Sample records for human buffy coat

  1. Comparative Analysis of the Dark Ground Buffy Coat Technique (DG ...

    African Journals Online (AJOL)

    The prevalence of typanosome infection in 65 cattle reared under expensive system of management was determined using the dark ground buffy coat (DG) technique and the enzyme-linkedimmunisorbent assay (ELISA). The DG technique showed that there were 18 positive cases (27.69%) of total number of animals, made ...

  2. Hemostatic function of buffy coat platelets in additive solution treated with pathogen reduction technology

    DEFF Research Database (Denmark)

    Ostrowski, Sisse R; Bochsen, Louise; Windeløv, Nis Agerlin

    2011-01-01

    BACKGROUND: Pathogen reduction technologies (PRTs) may influence the hemostatic potential of stored platelet (PLT) concentrates. To investigate this, buffy coat PLTs (BCPs) stored in PLT additive solution (SSP+) with or without Mirasol PRT treatment (CaridianBCT Biotechnologies) were compared...

  3. Mini buffy coat photopheresis for children and critically ill patients with extracorporeal photopheresis contraindications.

    Science.gov (United States)

    Hackstein, Holger; Misterek, Joachim; Nockher, Angelika; Reiter, Alfred; Bein, Gregor; Woessmann, Willi

    2009-11-01

    Conventional extracorporeal photopheresis (ECP) has proven efficacy for the treatment of several diseases but is limited to patients with sufficient body weight. A novel simplified mini buffy coat ECP technique that allows treatment of small children and patients with apheresis contraindications has been developed. White blood cell (WBC)-rich buffy coat fractions were prepared from 5 to 8 mL/kg whole blood in a closed system, diluted, and ultraviolet A (UVA)-irradiated after addition of 8-methoxypsoralen (8-MOP). Apoptosis and cell death were analyzed by annexin V and 7-aminoactinomycin staining. Lymphocyte proliferation was measured after CD3/CD28 and phytohemagglutinin (PHA) stimulation. Autologous residual blood and UVA-irradiated buffy coat were returned to the patients. Fifty-six mini buffy coat ECP procedures were applied to three children with acute steroid-refractory skin graft-versus-host disease and apheresis contraindications. Mean whole blood and buffy coat volumes were 166 (+/-61.8) and 8 (+/-1.6) mL, respectively, and resulted in a hematocrit of 2.2% (+/-0.4) after saline dilution (median +/- SD). UVA irradiation of 8-MOP buffy coat preparations resulted in significant induction of WBC apoptosis at 48-72 hours (p laboratory side effects were observed during mini ECP procedures and the three patients responded to the therapy. Mini buffy coat ECP induces apoptosis and lymphocyte proliferation inhibition, both of which occur after standard ECP. This study proposes that mini buffy coat ECP be used as a simple and inexpensive alternative to classical ECP in children and adult patients with apheresis contraindications.

  4. A preliminary comparative report of quantitative buffy coat and modified quantitative buffy coat with peripheral blood smear in malaria diagnosis.

    Science.gov (United States)

    Kochareka, Manali; Sarkar, Sougat; Dasgupta, Debjani; Aigal, Umesh

    2012-10-01

    The quantitative buffy coat (QBC) technique is a method of diagnosing malarial parasites based on micro-centrifugation, fluorescence, and density gradient of infected red blood cells. The aim of the present study was to modify the QBC technique in order to reduce the cost per test of malaria diagnosis. This was achieved by introducing some modifications to routine QBC wherein REMI centrifuge (cost Rs 19000/-) and ultra-violet microscope (Rs 115000) were used instead of parafuge (Rs 108000) and paralens (Rs 293625/-). With the above modification, the cost per test for laboratories dealing with high patient load was reduced by 13%, whereas for smaller laboratories with low patient load, the cost per test was reduced by 48%. This is a significant difference in cost. The results of the modified QBC method were compared with the current diagnostic methods: peripheral blood smear (PBS) and routine QBC. Blood samples collected from 96 patients were subjected to the above tests. Considering PBS as the gold standard, routine QBC showed 91% sensitivity and 96% specificity for Plasmodium vivax- and 91% sensitivity and 94% specificity for Plasmodium falciparum-infected patients. It was seen that the modified QBC technique had 91% sensitivity and 98% specificity for P. vivax and 91% sensitivity and 96% specificity for P. falciparum. It was concluded that modification of the QBC technique renders it cheaper without compromising the specificity and sensitivity of the method.

  5. Identification of mast cells in buffy coat preparations from dogs with inflammatory skin diseases.

    Science.gov (United States)

    Cayatte, S M; McManus, P M; Miller, W H; Scott, D W

    1995-02-01

    In 100 dogs with 4 inflammatory dermatologic diseases, buffy coat preparations from EDTA-treated blood samples were examined cytologically. Fifty-four dogs had atopy, 26 had flea-bite hypersensitivity, 17 had sarcoptic mange, and 3 had food allergy. Twenty-eight dogs had 2 or more concurrent skin diseases; most of these had secondary pyoderma. Dogs did not have mast cell tumors. Thirteen samples contained 1 or more mast cells/4 slides reviewed. This study revealed that dogs with inflammatory skin diseases can have a few to many mast cells evident on cytologic examination of buffy coat preparations.

  6. In vitro cell quality of buffy coat platelets in additive solution treated with pathogen reduction technology

    DEFF Research Database (Denmark)

    Ostrowski, Sisse R; Bochsen, Louise; Salado-Jimena, José A

    2010-01-01

    Pathogen reduction technologies (PRTs) may induce storage lesion in platelet (PLT) concentrates. To investigate this, buffy coat PLTs (BCPs) in PLT additive solution (AS; SSP+) with or without Mirasol PRT (CaridianBCT Biotechnologies) were assessed by quality control tests and four-color flow...

  7. Preparation of leukocyte-poor platelet concentrates from buffy coats. I. Special inserts for centrifuge cups

    NARCIS (Netherlands)

    Pietersz, R. N.; Reesink, H. W.; Dekker, W. J.; Fijen, F. J.

    1987-01-01

    A special insert was developed for centrifuge cups in order to prepare leukocyte-poor platelet concentrates from buffy coats by using quadruple citrate phosphate dextrose-saline adenine glucose mannitol systems from different manufacturers. Each centrifuge cup could contain up to 4 sets of double

  8. Molecular diagnosis of toxoplasmosis: value of the buffy coat for the detection of circulating Toxoplasma gondii.

    Science.gov (United States)

    Brenier-Pinchart, Marie-Pierre; Capderou, Elodie; Bertini, Rose-Laurence; Bailly, Sébastien; Fricker-Hidalgo, Hélène; Varlet-Marie, Emmanuelle; Murat, Jean-Benjamin; Sterkers, Yvon; Touafek, Fériel; Bastien, Patrick; Pelloux, Hervé

    2015-08-01

    Early detection of Toxoplasma tachyzoites circulating in blood using PCR is recommended for immunosuppressed patients at high risk for disseminated toxoplasmosis. Using a toxoplasmosis mouse model, we show that the sensitivity of detection is higher using buffy coat isolated from a large blood volume than using whole blood for this molecular monitoring. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Cord blood buffy coat DNA methylation is comparable to whole cord blood methylation.

    Science.gov (United States)

    Dou, John; Schmidt, Rebecca J; Benke, Kelly S; Newschaffer, Craig; Hertz-Picciotto, Irva; Croen, Lisa A; Iosif, Ana-Maria; LaSalle, Janine M; Fallin, M Daniele; Bakulski, Kelly M

    2018-01-01

    Cord blood DNA methylation is associated with numerous health outcomes and environmental exposures. Whole cord blood DNA reflects all nucleated blood cell types, while centrifuging whole blood separates red blood cells, generating a white blood cell buffy coat. Both sample types are used in DNA methylation studies. Cell types have unique methylation patterns and processing can impact cell distributions, which may influence comparability. We evaluated differences in cell composition and DNA methylation between cord blood buffy coat and whole cord blood samples. Cord blood DNA methylation was measured with the Infinium EPIC BeadChip (Illumina) in eight individuals, each contributing buffy coat and whole blood samples. We analyzed principal components (PC) of methylation, performed hierarchical clustering, and computed correlations of mean-centered methylation between pairs. We conducted moderated t-tests on single sites and estimated cell composition. DNA methylation PCs were associated with individual (P PC1 = 1.4 × 10 -9 ; P PC2 = 2.9 × 10 -5 ; P PC3 = 3.8 × 10 -5 ; P PC4 = 4.2 × 10 -6 ; P PC5 = 9.9 × 10 -13 , P PC6 = 1.3 × 10 -11 ) and not with sample type (P PC1-6 >0.7). Samples hierarchically clustered by individual. Pearson correlations of mean-centered methylation between paired samples ranged from r = 0.66 to r = 0.87. No individual site significantly differed between buffy coat and whole cord blood when adjusting for multiple comparisons (five sites had unadjusted Pcoat and whole cord blood are much lower than inter-individual variation, demonstrating that both sample preparation types can be analytically combined and compared.

  10. Generation of Induced Pluripotent Stem Cells from Frozen Buffy Coats using Non-integrating Episomal Plasmids.

    Science.gov (United States)

    Meraviglia, Viviana; Zanon, Alessandra; Lavdas, Alexandros A; Schwienbacher, Christine; Silipigni, Rosamaria; Di Segni, Marina; Chen, Huei-Sheng Vincent; Pramstaller, Peter P; Hicks, Andrew A; Rossini, Alessandra

    2015-06-05

    Somatic cells can be reprogrammed into induced pluripotent stem cells (iPSCs) by forcing the expression of four transcription factors (Oct-4, Sox-2, Klf-4, and c-Myc), typically expressed by human embryonic stem cells (hESCs). Due to their similarity with hESCs, iPSCs have become an important tool for potential patient-specific regenerative medicine, avoiding ethical issues associated with hESCs. In order to obtain cells suitable for clinical application, transgene-free iPSCs need to be generated to avoid transgene reactivation, altered gene expression and misguided differentiation. Moreover, a highly efficient and inexpensive reprogramming method is necessary to derive sufficient iPSCs for therapeutic purposes. Given this need, an efficient non-integrating episomal plasmid approach is the preferable choice for iPSC derivation. Currently the most common cell type used for reprogramming purposes are fibroblasts, the isolation of which requires tissue biopsy, an invasive surgical procedure for the patient. Therefore, human peripheral blood represents the most accessible and least invasive tissue for iPSC generation. In this study, a cost-effective and viral-free protocol using non-integrating episomal plasmids is reported for the generation of iPSCs from human peripheral blood mononuclear cells (PBMNCs) obtained from frozen buffy coats after whole blood centrifugation and without density gradient separation.

  11. Quality Analysis of DNA from Cord Blood Buffy Coat: The Best Neonatal DNA Source for Epidemiological Studies?

    Science.gov (United States)

    Zhou, Guangdi; Li, Qin; Huang, Lisu; Wu, Yuhang; Wu, Meiqin; Wang, Weiye C

    2016-04-01

    Umbilical cord blood is an economical and easy to obtain source of high-quality neonatal genomic DNA. However, although large numbers of cord blood samples have been collected, information on the yield and quality of the DNA extracted from cord blood is scarce. Moreover, considerable doubt still exists on the utility of the buffy coat instead of whole blood as a DNA source. We compared the sample storage and DNA extraction costs for whole blood, buffy coat, and all-cell pellet. We evaluated three different DNA purification kits and selected the most suitable one to purify 1011 buffy coat samples. We determined the DNA yield and optical density (OD) ratios and analyzed 48 single-nucleotide polymorphisms using time-of-flight mass spectrometry (TOF MS). We also analyzed eight possible preanalytical variables that may correlate with DNA yield or quality. Buffy coat was the most economical and least labor-intensive source for sample storage and DNA extraction. The average yield of genomic DNA from 200 μL of buffy coat sample was 16.01 ± 8.00 μg, which is sufficient for analytic experiments. The mean A260/A280 ratio and the mean A260/A230 ratio were 1.89 ± 0.09 and 1.95 ± 0.66, respectively. More than 99.5% of DNA samples passed the TOF MS test. Only hemolysis showed a strong correlation with OD ratios of DNA, but not with yield. Our findings show that cord blood buffy coat yields high-quality DNA in sufficient quantities to meet the requirements of experiments. Buffy coat was also found to be the most economic, efficient, and stable source of genomic DNA.

  12. Intralesional autotherapy of cutaneous leishmaniasis with buffy coat cells: cytological findings

    DEFF Research Database (Denmark)

    Dabiri, S; Meymandi, S S; Hayes, M M

    2000-01-01

    The skin lesions of five patient volunteers with dry-type cutaneous leishmaniasis were treated by intralesional injection of auto-leukocytes prepared from buffy coat of the patient's own blood. Giemsa stained, air-dried cytological smear preparations were prepared from scrapings taken from...... the margins of the lesions. The cellular interaction between the organism and the inflammatory response of the host was studied. All lesions showed clinical evidence of regression. The cytological findings suggested progressive degradation of the Leishman donovan (LD) bodies within the parasitophorous...

  13. c-DNA of HIV-1 detection on spot of Buffy-Coat of leukocytes (DBCS)

    OpenAIRE

    Marco Rossi de Gasperis; Maria Daniela Caione; Carlo Concato; Ersilia Fiscarelli; Nicola Di Pietro; Vittorio Salotti; Lorenza Putignani; Donato Menichella; Francesco Callea

    2010-01-01

    Introduction:The elective way for the diagnosis of HIV-1-infection in the window period and in children under the age of 16-18 months is to search virus integrated in leukocytes. Aim of the study was to assess the sensitivity and specificity of extraction from Buffy-Dried Coat Spot (DBCS) in leukocyte to detect c-DNA with nested-PCR in HIV-1-infected individuals compared to Dried Blood Spot (DBS) both extracted by automated instrument EZ1 (QIAGEN, Hilden, Germany). Both DBCS and both DBS were...

  14. Function of irradiated polymorphonuclear leukocytes obtained by buffy-coat centrifugation

    International Nuclear Information System (INIS)

    Wheeler, J.G.; Abramson, J.S.; Ekstrand, K.

    1984-01-01

    Several studies suggest that transfusion of polymorphonuclear leukocytes (PMNs) may be beneficial in the treatment of septic neonatal patients. Because of expense, donor availability, and the technical effort involved in obtaining PMNs by intermittent or continuous flow leukapheresis, buffy coat centrifugation of whole blood has been suggested as an alternative source. An in vitro study was performed to determine whether PMNs collected by this method have adequate oxidative and migratory function measured by chemiluminescence (CL) and chemotaxis under agarose (CT), respectively. Whole blood samples from six adult volunteers were drawn into citrate-phosphate-dextrose-adenine-one and stored at 4 degrees C for 0 to 48 hours. One-half of each sample was irradiated with 1500 rads. PMNs isolated from the buffy coat of these samples had greater than 80 percent normal CT and CL following 0 to 28 hours of storage in whole blood. Irradiation caused no depression in function. Units of whole blood yielded 1.11 +/- 0.40 X 10(9) PMNs per unit. This study indicates that transfusion of radiated PMNs obtained from stored whole blood that is less than 28 hours old is reasonable to use in studies involving PMN transfusions

  15. Biological Dosimetry of In Vitro Irradiation with Radionuclides : Comparison of Whole Blood, Lymphocyte and Buffy Coat Culture

    International Nuclear Information System (INIS)

    Kim, Jong Ho; Lee, Dong Soo; Choi, Chang Woon; Chung, June Key; Lee, Myung Chul; Koh, Chang Soon; Kim, Chong Soon; Kim, Hee Geun; Kang, Duck Won; Song, Myung Jae

    1995-01-01

    The purpose of this study was to establish mononuclear cell cultures such as lymphocytes or buffy coat for the biological dosimetry of in vitro irradiation of the radionuclide Tc-99m in order to exclude the effect of residual doses seen in the cultures of whole blood. Biological dosimetry of Tc-99m on cultured mononuclear cells at doses ranging from 0.05 to 6.00 Gy, by scoring unstable chromosomal aberrations(Ydr) observed in cultured lymphocytes, were performed using peripheral venous blood of healthy normal person. The results showed that; (1) In vitro irradiation of radioisotope in separated lymphocyte or buffy coat showed trace amount af residual doses of isotope after washing. Residual doses of isotopes are increased in proportion tn exposed time and irradiated dose without difference between I-131 anct Tc-99m. (2) We obtained these linear-quadratic dose response equations in lymphocyte and buffy coat culture after in vitro irradiation of Tc-99m, respectively (Ydr = 0,001949 D 2 +0,006279D+ 0.000185; Ydr= 0.002531 D 2 -0.003274 D+0.003488). In conclusion, the linear quadrstic dose response equation from in vitro irradiation of Tc-99m with lymphocyte and buffy coat culture was thought to be useful for assessing Tc-99m indueed biological effects. And mononuclear cell cultures seem to be the most appropriate experimental model for the assessment of biological dosimetry of internal irradiation of radionuclides.

  16. [Quality of buffy-coat-derived platelet concentrates prepared using automated system terumo automated centrifuge and separator integration (TACSI)].

    Science.gov (United States)

    Zebrowska, Agnieszka; Lipska, Alina; Rogowska, Anna; Bujno, Magdalena; Nedzi, Marta; Radziwon, Piotr

    2011-03-01

    Platelet recovery, and viability, and function is strongly dependent on the method of the preparation of platelet concentrate (PC). The glucose consumption, decrease of pH, release of alpha granules during storage in platelet concentrate impair their clinical effectiveness. To compare of the quality of buffy-coat-derieved platelet concentrates prepared using automatic system terumo automated centrifuge and separator integration (TACSI) and stored over 7 days. PCs were prepared from buffy coats using manual method (group I), or automatic system TACSI (group II). Fifteen PCs prepared from the 5 buffy coats each were stored over 7 days in 22-24 degrees C and tested. Samples were taken from the PCs container on days 1 and 7. The following laboratory tests were performed: number of platelets, platelets derived microparticles, CD62P expression, platelet adhesion, pH, glucose, lactate dehydrogenase activity. We have observed higher expression of CD62P in PCs prepared using manual method compared to the PCs produced automatically Platelet recovery was significantly higher in PCs prepared using automatic systems compare to manual method. Compared to manual methods, automatic system for preparation of buffy coats, is more efficient and enable production of platelets concentrates of higher quality.

  17. White blood cell fragments in platelet concentrates prepared by the platelet-rich plasma or buffy-coat methods

    NARCIS (Netherlands)

    Dijkstra-Tiekstra, M. J.; van der Schoot, C. E.; Pietersz, R. N. I.; Reesink, H. W.

    2005-01-01

    BACKGROUND AND OBJECTIVES: White blood cell (WBC) fragments in platelet concentrates (PCs) may induce allo-immunization in the recipient. MATERIALS AND METHODS: As the level of WBC fragments can differ between PCs produced using different methods, we compared PCs prepared by using the buffy-coat

  18. Use of buffy coat thick films in detecting malaria parasites in patients with negative conventional thick films.

    Science.gov (United States)

    Duangdee, Chatnapa; Tangpukdee, Noppadon; Krudsood, Srivicha; Wilairatana, Polrat

    2012-04-01

    To determine the frequency of malaria parasite detection from the buffy coat blood films by using capillary tube in falciparum malaria patients with negative conventional thick films. Thirty six uncomplicated falciparum malaria patients confirmed by conventional thick and thin films were included in the study. The patients were treated with artemisinin combination therapy at Hospital for Tropical Diseases, Bangkok, Thailand for 28 day. Fingerpricks for conventional blood films were conducted every 6 hours until negative parasitemia, then daily fingerpricks for parasite checks were conducted until the patients were discharged from hospital. Blood samples were also concurrently collected in 3 heparinized capillary tubes at the same time of fingerpricks for conventional blood films when the prior parasitemia was negative on thin films and parasitemia was lower than 50 parasites/200 white blood cells by thick film. The first negative conventional thick films were compared with buffy coat thick films for parasite identification. Out of 36 patients with thick films showing negative for asexual forms of parasites, buffy coat films could detect remaining 10 patients (27.8%) with asexual forms of Plasmodium falciparum. The study shows that buffy coat thick films are useful and can detect malarial parasites in 27.8% of patients whose conventional thick films show negative parasitemia.

  19. Platelet storage lesion in interim platelet unit concentrates: A comparison with buffy-coat and apheresis concentrates.

    Science.gov (United States)

    Singh, Sukhi; Shams Hakimi, Caroline; Jeppsson, Anders; Hesse, Camilla

    2017-12-01

    Platelet storage lesion is characterized by morphological changes and impaired platelet function. The collection method and storage medium may influence the magnitude of the storage lesion. The aim of this study was to compare the newly introduced interim platelet unit (IPU) platelet concentrates (PCs) (additive solution SSP+, 40% residual plasma content) with the more established buffy-coat PCs (SSP, 20% residual plasma content) and apheresis PCs (autologous plasma) in terms of platelet storage lesions. Thirty PCs (n=10 for each type) were assessed by measuring metabolic parameters (lactate, glucose, and pH), platelet activation markers, and in vitro platelet aggregability on days 1, 4, and 7 after donation. The expression of platelet activation markers CD62p (P-selectin), CD63 (LAMP-3), and phosphatidylserine was measured using flow cytometry and in vitro aggregability was measured with multiple electrode aggregometry. Higher platelet activation and lower in vitro aggregability was observed in IPU than in buffy-coat PCs on day 1 after donation. In contrast, metabolic parameters, expression of platelet activation markers, and in vitro aggregability were better maintained in IPU than in buffy-coat PCs at the end of the storage period. Compared to apheresis PCs, IPU PCs had higher expression of activation markers and lower in vitro aggregability throughout storage. In conclusion, the results indicate that there are significant differences in platelet storage lesions between IPU, buffy-coat, and apheresis PCs. The quality of IPU PCs appears to be at least comparable to buffy-coat preparations. Further studies are required to distinguish the effect of the preparation methods from storage conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Characterization of buffy coat-derived granulocytes for clinical use: a comparison with granulocyte colony-stimulating factor/dexamethasone-pretreated donor-derived products.

    Science.gov (United States)

    van de Geer, A; Gazendam, R P; Tool, A T J; van Hamme, J L; de Korte, D; van den Berg, T K; Zeerleder, S S; Kuijpers, T W

    2017-02-01

    Buffy coat-derived granulocytes have been described as an alternative to the apheresis product from donors pretreated with dexamethasone and granulocyte colony-stimulating factor (G-CSF). The latter is - dependent on the local and national settings - obtained following a demanding and time-consuming procedure, which is undesirable in critically ill septic patients. In contrast, buffy coat-derived products have a large volume and are often heavily contaminated with red cells and platelets. We developed a new pooled buffy coat-derived product with high purity and small volume, and performed a comprehensive functional characterization of these granulocytes. We pooled ten buffy coats following the production of platelet concentrates. Saline 0·9% was added to decrease the viscosity and the product was split into plasma, red cells and a 'super' buffy coat. Functional data of the granulocytes were compared to those obtained with granulocytes from healthy controls and G-CSF/dexamethasone-pretreated donors. Buffy coat-derived granulocytes showed adhesion, chemotaxis, reactive oxygen species production, degranulation, NETosis and in vitro killing of Staphylococcus aureus, Escherichia coli and Aspergillus species comparable to control and G-CSF/dexamethasone-derived granulocytes. Candida killing was superior compared to G-CSF/dexamethasone-derived granulocytes. Immunophenotyping was normal; especially no signs of activation in the buffy coat-derived granulocytes were seen. Viability was reduced. Buffy coats are readily available in the regular blood production process and would take away the concerns around the apheresis product. The product described appears a promising alternative for transfusion purposes. © 2017 International Society of Blood Transfusion.

  1. Randomised comparison of leucocyte-depleted versus buffy-coat-poor blood transfusion and complications after colorectal surgery

    DEFF Research Database (Denmark)

    Jensen, L S; Kissmeyer-Nielsen, P; Wolff, B

    1996-01-01

    BACKGROUND: Allogeneic blood transfusion is associated with an increased frequency of postoperative infection. We studied whether such events can be avoided by the intraoperative and postoperative use of leucocyte-depleted blood. METHODS: 589 consecutive patients scheduled for elective colorectal...... surgery were randomised to receive buffy-coat poor (n = 299) or filtered leucocyte-depleted red-cells (n = 290) when transfusion was indicated. 260 patients actually received blood transfusion. Three patients were excluded from analysis. FINDINGS: The 142 patients randomised to and transfused with buffy......-coat-poor blood had a significantly higher frequency of wound infections and intra-abdominal abscesses than the 155 patients who were allocated to this group but who were not transfused. (12 vs 1%, p blood also had a significantly...

  2. Quality of red cell concentrates in relation to the volume of the buffy coat removed by automated processing in a top and bottom system.

    Science.gov (United States)

    Pietersz, R N; Dekker, W J; Reesink, H A

    1991-01-01

    The effect of automated removal of increasing volumes of buffy coat in a 'top and bottom' system on the composition of red cell concentrates (RCC) was investigated. The volume of the buffy coat was adjusted to group 1:50 ml (n = 31), group 2: 70 ml (n = 31) and group 3: 100 ml (n = 31), respectively. The numbers of platelets and leukocytes in the buffy coats were comparable between the groups, whereas the red cell volumes in the buffy coats showed a significant difference (17 +/- 3.6 ml group 1, versus 22 +/- 4.1 ml group 2 and 26 +/- 3.88 ml group 3; p less than 0.001). The volumes, hematocrits and cell counts of the RCC were not significantly different. The plasma volumes were inversely correlated with the volume of buffy coat removed, i.e. 268 +/- 19 ml group 1, versus 257 +/- 15 ml group 2 and 233 +/- 20 ml group 3 (p less than 0.001). We conclude that in the 'top and bottom' system an increase of the volume of the buffy coat from 50 to 100 ml did not improve the quality of the RCC regarding contamination with leukocytes and platelets.

  3. c-DNA of HIV-1 detection on spot of Buffy-Coat of leukocytes (DBCS

    Directory of Open Access Journals (Sweden)

    Marco Rossi de Gasperis

    2010-03-01

    Full Text Available Introduction:The elective way for the diagnosis of HIV-1-infection in the window period and in children under the age of 16-18 months is to search virus integrated in leukocytes. Aim of the study was to assess the sensitivity and specificity of extraction from Buffy-Dried Coat Spot (DBCS in leukocyte to detect c-DNA with nested-PCR in HIV-1-infected individuals compared to Dried Blood Spot (DBS both extracted by automated instrument EZ1 (QIAGEN, Hilden, Germany. Both DBCS and both DBS were compared with those tests from whole blood by conventional DNA-extraction Methods: Five ml of whole blood from 50 HIV-infected individuals were collected. 40 μl of each sample were spotted on “FTA ELUTE Micro Card” (Whatman, Inc., Clifton, NJ, 200 μl were extracted according to the manual procedure (QIAGEN “QIAamp DNA minikit and the remaining sample was incubated at 37 °C for 120 minutes. Plasma was centrifuged at 1000 rcf/1g for 10 minutes at room temperature. Forty μl of the obtained buffy-coat was spotted. Both DBCS and both DBS were dried at room temperature for 24 hours.Two of 5 punch from each spot were extracted with TISSUE DNA kit (Biorobot EZ1 DSP “Qiagen” and eluted in 50 μl of buffer.The recovery of genomic DNA was measured amplifying the ß-globin gene by Real-Time “SybrGreen I”.The DNA was amplified for the “pol” gene of HIV-1 by nested PCR and revealed in “SYBR-green I”. Eight HIV-antibody-negative samples were used as internal control. Results:The experimental protocol adopted for the DBCS showed high sensitivity and specificity.The extracted DNA from DBS and DBCS was characterized by excellent quality and without any inhibitory agents. The amount of proviral DNA extracted from DBCS is similar to that obtained by conventional extraction, while the DBS test was significantly less sensitive. Conclusion:These preliminary data suggest that the amount of c-DNA obtained with DBS technique is often not enough for the

  4. Isolation of monocytes from whole blood-derived buffy coats by continuous counter-flow elutriation.

    Science.gov (United States)

    Schwanke, Uwe; Nabereit, Anja; Moog, Rainer

    2006-10-01

    Monocytes (MOs) are the most commonly used precursors for the generation of dendritic cells (DCs) in vitro. Continuous counter-flow elutriation represents a promising tool to isolate MOs from white blood cell (WBC) products. Thirty whole blood-derived, AB0-identical buffy coats (BCs) were pooled using sterile technique (n = 5 experiments). For red blood cell (RBC) and polymorphonuclear cell (PMN) depletion, the BC pools were processed in a Cobe Spectra device (Gambro BCT) using the bone marrow program. Subsequently, continuous counter-flow elutriation in an Elutra device (Gambro BCT) was performed to enrich and purify MOs. BC pool volume averaged 1,260 +/- 14 ml containing 7.7 +/- 1.1 x 10(9) MOs. During 107 +/- 7 min, Cobe Spectra operation, the BC pools were processed for several times, and approximately 9,749 +/- 605 ml volume passed the device. Product volume and MO yield averaged 160 +/- 16 ml, and 4.3 +/- 1.3 x 10(9) cells, respectively. Elutra operation was performed within 59 +/- 0 min and yielded 2.5 +/- 0.9 x 10(9) MOs with a purity of 60 +/- 12%. Compared with the Cobe Spectra product cell count, MO recovery by Elutra averaged 59 +/- 10%. Elutriation of MOs from pooled BCs using Elutra exhibited comparatively low recovery and purity rates. This shortcoming may be due to the nature of the source material. Optimization of the elutriation procedure is necessary to improve MO enrichment from BCs.

  5. EXTENDED STORAGE OF BUFFY-COAT PLATELET CONCENTRATES IN PLASMA OR A PLATELET ADDITIVE SOLUTION

    Science.gov (United States)

    Slichter, Sherrill J.; Bolgiano, Doug; Corson, Jill; Jones, Mary Kay; Christoffel, Todd; Bailey, S. Lawrence; Pellham, Esther

    2014-01-01

    Background Platelet concentrates prepared from whole blood in the U.S. are made using the platelet-rich-plasma (PRP) method. The platelet concentrates must be made within 8 hours of blood collection and stored for only 5 days. In Europe and Canada, platelet concentrates are made using the buffy-coat (BC) method from whole blood held overnight at 22°C and storage times may be up to 7 days. Our studies were designed to determine how long BC platelets can be stored in plasma or Plasmalyte while meeting the FDA’s post-storage viability criteria. Study Design, Materials, And Methods Normal subjects donated whole blood that was stored at 22°C for 22 ± 2 hours prior to preparation of BC platelets. Platelets were stored for 5 to 8 days in either plasma or Plasmalyte concentrations of 65% or 80%. Radiolabeled autologous stored versus fresh platelet recoveries and survivals were assessed as well as post-storage in vitro assays. Results BC platelets stored in either plasma or 65% Plasmalyte met FDA post-storage platelet recovery criteria for 7 days but survivals for only 6 days, while storage in 80% Plasmalyte gave very poor results. Both stored platelet recoveries and survivals correlated with the same donor’s fresh results, but the correlation was much stronger between recoveries than survivals. In vitro measures of extent of shape change, morphology score, and pH best predicted post-storage platelet recoveries, while annexin V binding best predicted platelet survivals. Conclusion BC platelets stored in either plasma or 65% Plasmalyte meet FDA’s post-storage viability criteria for 6 days. PMID:24673482

  6. In vitro viability effects on apheresis and buffy-coat derived platelets administered through infusion pumps

    Directory of Open Access Journals (Sweden)

    Sandgren P

    2014-12-01

    Full Text Available Per Sandgren,1,2 Veronica Berggren,3 Carl Westling,1,2 Viveka Stiller1 1Department of Clinical Immunology and Transfusion Medicine, Karolinska University Hospital, 2Department of Laboratory Medicine, Karolinska Institutet, 3Department of Neonatology, Karolinska University Hospital, Stockholm, SwedenBackground: Different infusion pump systems as well as gravity infusion have been widely used in neonatal transfusion. However, the limited number of published studies describing the use of infusion pumps on platelets illustrates the necessity for more robust data.Methods: To evaluate the potential in vitro effects on the cellular, metabolic, functional and phenotypic properties of platelets, we set up a four-arm paired study simultaneously comparing the use of different infusion pumps (Alaris® CC/GP with unexposed platelets. The platelet units (n=8 were either produced by the apheresis technique and suspended in 100% plasma or derived from buffy coats to yield platelet units stored in approximately 30% plasma and 70% SSP+. Fresh and 5-day old platelets were tested.Results: Regardless of the production system or storage time used, no significant differences were observed in glucose and lactate concentration, pH, adenosine triphosphate levels, response to extent of shape change, hypotonic shock response reactivity, and CD62P expression. Similarly, no differences were observed in expression of the conformational epitope on glycoprotein IIb/IIIa, determined using procaspase-activating compound 1, or in the expression of CD42b and platelet-endothelial cell adhesion molecule-1 in a comparison between platelets administered through infusion pumps versus unexposed platelets.Conclusion: Using Alaris CC/GP infusion pumps had no influence on the cellular, functional, and phenotypic in vitro properties of platelets. This fact seems not to be affected by different production systems or storage time.Keywords: platelets, neonatal platelet transfusion

  7. Detection of Trypanosoma congolense type savannah in field samples of buffy coats of bovins using PCR-ELISA

    International Nuclear Information System (INIS)

    Sidibe, I.

    2007-01-01

    PCR-ELISA was set up to detect strain of Trypanosoma congolense type savannah in field samples of buffy coats. Results of PCR-ELISA and PCR were compared and the sensibility and specificity of both techniques were also compared with those of the method of Murray [1] for the detection of TCS in 257 samples. The PCR products were labelling with DIG-dUTP during amplification cycles of the repetitive satellite DNA. A DNA biotinyled capture probe was used to detect the amplicon by ELISA in streptavidine coated microplates. Both of PCR-ELISA and PCR were more sensible and more specific than the method of Murray. Indeed, for the 257 samples analysed by the three techniques, PCR-ELISA and PCR have detected TCS in 98 and 97 samples respectively, whereas the method of Murray has detected TCS in only 39 samples. In addition, PCRELISA and PCR had almost the same sensibility and specificity. So, PCR-ELISA and PCR have respectively detected TCS in 38.62% and 39.22% of all the 334 samples analysed by both techniques during this study. At the end of this study, the cost of analyse by PCR-ELISA of a sample of buffy coat, was evaluated at 1993 FCFA or Euro 3,04. (author) [fr

  8. Fully automated processing of buffy-coat-derived pooled platelet concentrates.

    Science.gov (United States)

    Janetzko, Karin; Klüter, Harald; van Waeg, Geert; Eichler, Hermann

    2004-07-01

    The OrbiSac device, which was developed to automate the manufacture of buffy-coat PLT concentrates (BC-PCs), was evaluated. In-vitro characteristics of BC-PC preparations using the OrbiSac device were compared with manually prepared BC-PCs. For standard processing (Std-PC, n = 20), four BC-PCs were pooled using 300 mL of PLT AS (PAS) followed by soft-spin centrifugation and WBC filtration. The OrbiSac preparation (OS-PC, n = 20) was performed by automated pooling of four BC-PCs with 300 mL PAS followed by centrifugation and inline WBC filtration. All PCs were stored at 22 degrees C. Samples were withdrawn on Day 1, 5, and 7 evaluating PTL count, blood gas analysis, glucose, lactate, LDH, beta-thromboglobulin, hypotonic shock response, and CD62p expression. A PLT content of 3.1 +/- 0.4 x 10(11) (OS-PCs) versus 2.7 +/- 0.5 x 10(11) (Std-PCs, p < 0.05) was found. A CV of 19 percent (Std-PC) versus 14 percent (OS-PC) suggests more standardization in the OS group. At Day 7, the Std-PCs versus OS-PCs showed a glucose consumption of 1.03 +/- 0.32 micro mol per 10(9) PLT versus 0.75 +/- 0.25 micro mol per 10(9) PLT (p < 0.001), and a lactate production of 1.50 +/- 0.86 micro mol per 10(9) versus 1.11 +/- 0.61 micro mol per 10(9) (p < 0.001). The pH (7.00 +/- 0.19 vs. 7.23 +/- 0.06; p < 0.001), pO(2) (45.3 +/- 18 vs. 31.3 +/- 10.4 mmHg; p < 0.01), and HCO(3) levels (4.91 +/- 1.49 vs. 7.14 +/- 0.95 mmol/L; p < 0.001) suggest a slightly better aerobic metabolism within the OS group. Only small differences in CD62p expression was observed (37.3 +/- 12.9% Std-PC vs. 44.8 +/- 6.6% OS-PC; p < 0.05). The OrbiSac device allows an improved PLT yield without affecting PLT in-vitro characteristics and may enable an improved consistency in product volume and yield.

  9. High DNA stability in white blood cells and buffy coat lysates stored at ambient temperature under anoxic and anhydrous atmosphere.

    Directory of Open Access Journals (Sweden)

    Anne-Lise Fabre

    Full Text Available Conventional storage of blood-derived fractions relies on cold. However, lately, ambient temperature preservation has been evaluated by several independent institutions that see economic and logistic advantages in getting rid of the cold chain. Here we validated a novel procedure for ambient temperature preservation of DNA in white blood cell and buffy coat lysates based on the confinement of the desiccated biospecimens under anoxic and anhydrous atmosphere in original hermetic minicapsules. For this validation we stored encapsulated samples either at ambient temperature or at several elevated temperatures to accelerate aging. We found that DNA extracted from stored samples was of good quality with a yield of extraction as expected. Degradation rates were estimated from the average fragment size of denatured DNA run on agarose gels and from qPCR reactions. At ambient temperature, these rates were too low to be measured but the degradation rate dependence on temperature followed Arrhenius' law, making it possible to extrapolate degradation rates at 25°C. According to these values, the DNA stored in the encapsulated blood products would remain larger than 20 kb after one century at ambient temperature. At last, qPCR experiments demonstrated the compatibility of extracted DNA with routine DNA downstream analyses. Altogether, these results showed that this novel storage method provides an adequate environment for ambient temperature long term storage of high molecular weight DNA in dehydrated lysates of white blood cells and buffy coats.

  10. High DNA stability in white blood cells and buffy coat lysates stored at ambient temperature under anoxic and anhydrous atmosphere

    Science.gov (United States)

    Luis, Aurélie; Colotte, Marthe; Tuffet, Sophie; Bonnet, Jacques

    2017-01-01

    Conventional storage of blood-derived fractions relies on cold. However, lately, ambient temperature preservation has been evaluated by several independent institutions that see economic and logistic advantages in getting rid of the cold chain. Here we validated a novel procedure for ambient temperature preservation of DNA in white blood cell and buffy coat lysates based on the confinement of the desiccated biospecimens under anoxic and anhydrous atmosphere in original hermetic minicapsules. For this validation we stored encapsulated samples either at ambient temperature or at several elevated temperatures to accelerate aging. We found that DNA extracted from stored samples was of good quality with a yield of extraction as expected. Degradation rates were estimated from the average fragment size of denatured DNA run on agarose gels and from qPCR reactions. At ambient temperature, these rates were too low to be measured but the degradation rate dependence on temperature followed Arrhenius’ law, making it possible to extrapolate degradation rates at 25°C. According to these values, the DNA stored in the encapsulated blood products would remain larger than 20 kb after one century at ambient temperature. At last, qPCR experiments demonstrated the compatibility of extracted DNA with routine DNA downstream analyses. Altogether, these results showed that this novel storage method provides an adequate environment for ambient temperature long term storage of high molecular weight DNA in dehydrated lysates of white blood cells and buffy coats. PMID:29190767

  11. Experience of buffy coat pooling of platelets as a supportive care in thrombocytopenic dengue patients: A prospective study

    Directory of Open Access Journals (Sweden)

    Kabita Chatterjee

    2014-01-01

    Full Text Available Random donor platelet (RDP is not sufficient to improve the platelet count in most thrombocytopenic patients. Single donor platelet (SDP or buffy coat pooled platelet (BCPP are the two choices to provide a full therapeutic dose of platelets. However, there are constraints in the preparation of SDP due to stringent donor selection procedure, time required for procedure, and need of special expensive equipments and kits. BCPP is widely practiced, especially in the European countries, since 1995. In India, we decided to adopt the procedure of buffy coat pooling of platelets, especially for economically backward patients and for emergencies. This study was prospectively conducted from September 2009 to September 2010. A total of 129 units of BCPP [tested prior for viral markers by enzyme-linked immunosorbent assay (ELISA and individual donor nucleic acid amplification test (ID-NAT] were issued to 129 patients suffering from dengue and were included in this study. For comparison between efficacy of SDP and BCCP, patients were divided into two groups of 50 each. The post-transfusion platelet counts of the patients were noted after 2 hours of transfusion for each type of component. The platelet yield varied from 2.5 to 4.4 Χ 10ΉΉ in BCPP samples. The samples analyzed were sterile without any contamination. The different biochemical parameters were analyzed in detail. The observed post-transfusion platelet recovery and corrected count increment (CCI at 1 hour and 24 hours after BCPP transfusion were similar to that after SDP transfusion. Hence, we concluded that BCPP can be a low cost alternative to SDP in the times of emergencies like dengue and non-affordability by the patient for SDP.

  12. A rest period does not affect in vitro storage properties in apheresis platelets collected from the buffy coat layer.

    Science.gov (United States)

    Wagner, Stephen J; Seetharaman, Shalini; Kurtz, James

    2012-11-01

    A previous study demonstrated that several in vitro storage properties of apheresis platelets (PLTs) that are isolated by sedimentation against the collection container and subsequently resuspended can benefit from a rest period before continuous agitation. This study examines whether the in vitro storage properties of apheresis PLTs isolated by collection from the buffy coat layer benefit from a rest period before agitation. Freshly collected apheresis PLTs (Trima, GambroBCT) were divided into five 60-mL aliquots. One aliquot was immediately placed on a flat-bed agitator; the other aliquots were held on a laboratory bench for 1, 2, 4, and 6 hours before continuous agitation. Samples were obtained on Days 1, 5, and 7 for standard in vitro PLT assays. The experiment was repeated 12 times. For each sampling day, no significant differences were observed in aliquots held with or without a rest period for any of the following PLT properties: PLT content, mean PLT volume, pH, pCO2, bicarbonate, glucose, lactate, hypotonic shock response, extent of shape change, aggregation, morphology, CD62P, CD63, and CD42b. Although regression analysis identified several in vitro properties whose mean levels appeared to improve with increasing length of the rest period, maximum differences in mean levels were small (coat layer do not benefit from a rest period. © 2012 American Association of Blood Banks.

  13. Tick-Borne Relapsing Fever Imported from West Africa: Diagnosis by Quantitative Buffy Coat Analysis and In Vitro Culture of Borrelia crocidurae

    OpenAIRE

    van Dam, Alje P.; van Gool, Tom; Wetsteyn, José C. F. M.; Dankert, Jacob

    1999-01-01

    West African tick-borne relapsing fever (TBRF) is difficult to diagnose due to the low number of spirochetes in the bloodstream of patients. Previously, the causative microorganism, Borrelia crocidurae, had never been cultured in vitro. TBRF was rapidly diagnosed for two patients returning from western Africa with fever of unknown origin by quantitative buffy coat (QBC) analysis. Diagnosis was confirmed by intraperitoneal inoculation of blood specimens from patients into laboratory mice. In v...

  14. A combination of exosomes carrying TSA derived from HLA-A2-positive human white buffy coat and polyI:C for use as a subcellular antitumor vaccination.

    Science.gov (United States)

    Ren, Wei-na; Chang, Chun-kang; Fan, Hua-hua; Guo, Fang; Ren, Ya-na; Yang, Jie; Guo, Juan; Li, Xiao

    2011-01-01

    To improve its antitumor effect, we used human leukocyte antigen -A2 (HLA-A2)-positive human dendritic cell (DC)-derived DEXs (DC-derived exosomes) to support NY-ESO-1 antigen and polyI:C, with the aim of increasing the proliferation of specific cytotoxic T lymphocytes (CTL) in transgenic mice. Mature dendritic cells derived from peripheral blood mononuclear cells (PBMC) were isolated from the blood of healthy adults with positive HLA-2A. Using centrifuge and membrane ultrafiltration, EXO (exosomes) were extracted from the supernatant of DCs secretions. Transgenic C57 mice were immunized with human-derived tumor testis antigen NY-ESO-1/EXO, with or without polyI:C. Mice were sacrificed four weeks after immunization, and spleen cells were isolated and tested for function. The experiments included antigen-specific CTL proliferation, as tested by dimerization and antitumor effects for K562 cells as well as melanoma, tested at different ratios of effected cells:target cells (0:1, 10:1, 50:1, and 100:1). Dimerization experiments indicated that the effect of DEX/TSA (tumor specific antigens) + PolyI:C was 2.36 ± 1.10% and the control was 0.38 ± 0.31%, while the effect of DEX/TSA was 1.97 ± 0.63% and the control was 0.36 ± 0.07%. Antitumor effects by DEX/TSA: PolyI:C for the cell ratios of 0:1, 10:1, 50:1, and 100:1 were 11.14 ± 1.36%, 14.17 ± 0.62%, 15.71 ± 2.48%, and 24.31 ± 2.91%, respectively, for K562 cells. The antitumor effects for DEX/TSA for the cell ratios of 0:1, 10:1, 50:1, and 100:1 were 12.23 ± 2.25%, 13.10 ± 1.57%, 15.27 ± 2.93%, and 19.87 ± 2.72%, respectively, for K562 cells. With ratios of 10:1 and 100:1, the antitumor effects of DEX/TSA + PolyI:C were better than for the DEX/TSA group (P TSA derived from healthy human blood positive for HLA-A2 is a promising strategy for developing new subcellular antitumor vaccination.

  15. Whole blood treated with riboflavin and ultraviolet light: quality assessment of all blood components produced by the buffy coat method.

    Science.gov (United States)

    Schubert, Peter; Culibrk, Brankica; Karwal, Simrath; Serrano, Katherine; Levin, Elena; Bu, Daniel; Bhakta, Varsha; Sheffield, William P; Goodrich, Raymond P; Devine, Dana V

    2015-04-01

    Pathogen inactivation (PI) technologies are currently licensed for use with platelet (PLT) and plasma components. Treatment of whole blood (WB) would be of benefit to the blood banking community by saving time and costs compared to individual component treatment. However, no paired, pool-and-split study directly assessing the impact of WB PI on the subsequently produced components has yet been reported. In a "pool-and-split" study, WB either was treated with riboflavin and ultraviolet (UV) light or was kept untreated as control. The buffy coat (BC) method produced plasma, PLT, and red blood cell (RBC) components. PLT units arising from the untreated WB study arm were treated with riboflavin and UV light on day of production and compared to PLT concentrates (PCs) produced from the treated WB units. A panel of common in vitro variables for the three types of components was used to monitor quality throughout their respective storage periods. PCs derived from the WB PI treatment were of significantly better quality than treated PLT components for most variables. RBCs produced from the WB treatment deteriorated earlier during storage than untreated units. Plasma components showed a 3% to 44% loss in activity for several clotting factors. Treatment of WB with riboflavin and UV before production of components by the BC method shows a negative impact on all three blood components. PLT units produced from PI-treated WB exhibited less damage compared to PLT component treatment. © 2014 AABB.

  16. Comparison between microscopic examination, ELISA and quantitative buffy coat analysis in the diagnosis of falciparum malaria in an endemic population.

    Science.gov (United States)

    Tanpradist, S; Tharavanij, S; Yamokgul, P; Bualombai, P; Wongchotigul, V; Singhasivanon, P; Patarapotikul, J; Thammapalerd, N; Prasittisuk, C; Tantanasrikul, S

    1995-03-01

    Monoclonal antibody-based ELISA and QBC (quantitative buffy coat analysis) were tested in two endemic areas with low and high incidence of malaria in Kanchanaburi Province, West Thailand with annual parasite incidence in 1992 of 119 and 5 per 1,000 population, respectively. The numbers of individuals positive by thick blood film examination (TBF) for P. falciparum with or without P. vivax, and P. vivax only were 82 and 69, respectively. The detection limit of ELISA was 10 parasites/10(6) red blood cells (RBC) (0.001% parasitemia). Of 1,095 individuals involved in the study at the beginning of the study, ELISA showed sensitivity, specificity, positive predictive value and negative predictive value of 78.1%, 94.9%, 72% and 98.1%, respectively. Nine of 18 (50%) TBF-positive but ELISA-positive individuals had parasitemia of less than 10 parasites/10(6) RBC. High and low incidence areas did not affect the validity of our result. Regression analysis showed good correlation between log parasitemia and ELISA percent OD increase (Y = 0 + 64.9*logX, r = 0.65), and agreement between TBF and ELISA results was 95.9%. In a fortnightly follow-up, in 82 TBF-positive individuals, both ELISA and TBF positive rates correlatively declined with agreement of 96.3%. With samples taken on the first day of the study, the TBF and QBC results were also correlated with agreement of 95.8% for P. falciparum, 95.6% for P. vivax. During 8 week follow-up involving altogether 191 samples, agreement between TBF and QBC results were 87.4% for P. falciparum. QBC detected more cases with P. falciparum infections but detected smaller number of cases with P. vivax infections.

  17. Comparison of the platelet-rich plasma and buffy coat protocols for preparation of canine platelet concentrates.

    Science.gov (United States)

    Hoareau, Guillaume L; Jandrey, Karl E; Burges, Julie; Bremer, Daphne; Tablin, Fern

    2014-12-01

    Platelet (PLT) concentrates (PC) can be produced via the buffy coat (BC) or platelet-rich plasma (PRP) protocols. The 2 methods have not been compared with canine blood. The aims of the study were to compare the PLT, WBC, and RBC concentrations, in vitro PLT function, and markers of platelet storage lesion (PSL) in canine PC generated by 2 different protocols, and determine microbial growth throughout storage. PC from 8 healthy donor dogs were produced using 2 standard protocols, PRP and BC. PLT, WBC, and RBC counts, optical aggregometry assays, and PSL markers (pH, pCO2 , HCO3 , lactate and glucose concentrations, and LDH activity) were determined on storage days 0, 1, 3, 5, and 7. Aerobic and anaerobic bacterial cultures were also performed. Mean PLT counts were comparable between protocols and remained stable throughout storage up to day 7, while median WBC and RBC counts on day 0 were significantly higher in the BC-PC group (17,800 WBCs/μL; 195,000 RBCs/μL) than in the PRP-PC group (200 WBCs/μL; 10,000 RBCs/μL) (P = .012). In PRP-PC aggregometry, the median slope and amplitude in response to γ-thrombin and convulxin (+ ADP) were significantly decreased, and virtually absent in BC-PC during storage. PSL markers (lactate, LDH activity) were higher in BC-PC. Aerobic bacterial growth was observed in 2 PRP-PC and 1 BC-PC. This in vitro study suggests that PRP-PC had lesser WBC and RBC contamination and superior PLT function compared with BC-PC. In vivo studies are required to address safety and efficacy of PRP-PC. © 2014 American Society for Veterinary Clinical Pathology.

  18. Implementation of buffy-coat-derived pooled platelet concentrates for internal quality control of light transmission aggregometry: a proof of concept study.

    Science.gov (United States)

    Prüller, F; Rosskopf, K; Mangge, H; Mahla, E; von Lewinski, D; Weiss, E C; Riegler, A; Enko, D

    2017-12-01

    Essentials In platelet function testing, standardized internal controls (IQC) are not commercially provided. Platelet function testing was performed daily on aliquoted pooled platelet concentrates. Pooled platelet concentrates showed stability for control purposes from Monday to Friday. Pooled platelet concentrates provide the necessary steadiness to serve as IQC material. Background Standardized commercially available control material for internal quality control (IQC) of light transmission aggregometry (LTA) is still lacking. Moreover, the availability of normal blood donors to provide fresh platelets is difficult in small laboratories, where 'volunteers' may be in short supply. Objectives To evaluate the implementation of buffy-coat-derived pooled platelet concentrates (PCs) for IQC material for LTA. Methods We used buffy-coat-derived pooled PCs from the blood bank as IQC material for LTA. On each weekend one PC was prepared (> 200 mL) and aliquoted from the original storage bag on a daily basis in four baby bags (40-50 mL), which were delivered from Monday to Friday to our laboratory. The IQC measurements of at least 85 work-weeks (from Monday to Friday) were evaluated with this new IQC material. LTA was performed on a four-channel Chronolog 700 Aggregometer (Chronolog Corporation, Havertown, PA, USA) (agonists: collagen, adenosine diphosphate [ADP], arachidonic acid [AA] and thrombin receptor activator peptide-6 [TRAP-6]). Results The medians of platelet aggregation from IQC measurements with collagen, ADP and AA from Monday to Friday were 68.0-59.5, 3.0-2.0 and 51.0-50.0%, respectively, and the mean of platelet aggregation with TRAP-6 was 71.2-66.4%. Conclusions Buffy-coat-derived pooled PCs serve as a reliable and robust IQC material for LTA measurements and would be beneficial for the whole laboratory procedure and employees' safety. © 2017 International Society on Thrombosis and Haemostasis.

  19. Overcoming the bottleneck of platelet lysate supply in large-scale clinical expansion of adipose-derived stem cells: A comparison of fresh versus three types of platelet lysates from outdated buffy coat-derived platelet concentrates.

    Science.gov (United States)

    Glovinski, Peter V; Herly, Mikkel; Mathiasen, Anders B; Svalgaard, Jesper D; Borup, Rehannah; Talman, Maj-Lis M; Elberg, Jens J; Kølle, Stig-Frederik T; Drzewiecki, Krzysztof T; Fischer-Nielsen, Anne

    2017-02-01

    Platelet lysates (PL) represent a promising replacement for xenogenic growth supplement for adipose-derived stem cell (ASC) expansions. However, fresh platelets from human blood donors are not clinically feasible for large-scale cell expansion based on their limited supply. Therefore, we tested PLs prepared via three methods from outdated buffy coat-derived platelet concentrates (PCs) to establish an efficient and feasible expansion of ASCs for clinical use. PLs were prepared by the freeze-thaw method from freshly drawn platelets or from outdated buffy coat-derived PCs stored in the platelet additive solution, InterSol. Three types of PLs were prepared from outdated PCs with platelets suspended in either (1) InterSol (not manipulated), (2) InterSol + supplemented with plasma or (3) plasma alone (InterSol removed). Using these PLs, we compared ASC population doubling time, cell yield, differentiation potential and cell surface markers. Gene expression profiles were analyzed using microarray assays, and growth factor concentrations in the cell culture medium were measured using enzyme-linked immunosorbent assay (ELISA). Of the three PL compositions produced from outdated PCs, removal of Intersol and resuspension in plasma prior to the first freezing process was overall the best. This specific outdated PL induced ASC growth kinetics, surface markers, plastic adherence and differentiation potentials comparable with PL from fresh platelets. ASCs expanded in PL from fresh versus outdated PCs exhibited different expressions of 17 overlapping genes, of which 10 were involved in cellular proliferation, although not significantly reflected by cell growth. Only minor differences in growth factor turnover were observed. PLs from outdated platelets may be an efficient and reliable source of human growth supplement allowing for large-scale ASC expansion for clinical use. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights

  20. Tick-borne relapsing fever imported from West Africa: diagnosis by quantitative buffy coat analysis and in vitro culture of Borrelia crocidurae.

    Science.gov (United States)

    van Dam, A P; van Gool, T; Wetsteyn, J C; Dankert, J

    1999-06-01

    West African tick-borne relapsing fever (TBRF) is difficult to diagnose due to the low number of spirochetes in the bloodstream of patients. Previously, the causative microorganism, Borrelia crocidurae, had never been cultured in vitro. TBRF was rapidly diagnosed for two patients returning from western Africa with fever of unknown origin by quantitative buffy coat (QBC) analysis. Diagnosis was confirmed by intraperitoneal inoculation of blood specimens from patients into laboratory mice. In vitro experiments showed that QBC analysis may be as much as 100-fold more sensitive than thick smear. Spirochetes were also cultured from blood samples from both patients in modified Kelly's medium and were identified as B. crocidurae by partial sequencing of the PCR-amplified rrs gene.

  1. Effect of adhesive properties of buffy coat on the quality of blood components produced with Top & Top and Top & Bottom bags.

    Science.gov (United States)

    Cerelli, Eugenio; Nocera, Martina; Di Bartolomeo, Erminia; Panzani, Paola; Baricchi, Roberto

    2015-04-01

    The Transfusion Medicine Unit of Reggio Emilia currently collects whole blood using conventional quadruple Fresenius Top & Top bags. In this study, new Fresenius Top & Bottom bags were assessed and compared to the routine method with regards to product quality and operational requirements. Twenty-one whole blood units were collected with both the new and the traditional bags, and then separated. Quality control data were evaluated and compared in order to estimate yield and quality of final blood components obtained with the two systems. We collected other bags, not included in the ordinary quality control programme, for comparison of platelet concentrates produced by pools of buffy coat. Compared to the traditional system, the whole blood units processed with Top & Bottom bags yielded larger plasma volumes (+5.7%) and a similar amount of concentrated red blood cells, but with a much lower contamination of lymphocytes (-61.5%) and platelets (-86.6%). Consequently, the pooled platelets contained less plasma (-26.3%) and were significantly richer in platelets (+17.9%). This study investigated the effect of centrifugation on the adhesiveness of the buffy coat to the bag used for whole blood collection. We analysed the mechanism by which this undesirable phenomenon affects the quality of packed red blood cells in two types of bags. We also documented the incomparability of measurements on platelet concentrates performed with different principles of cell counting: this vexing problem has important implications for biomedical research and for the establishment of universal product standards. Our results support the conclusion that the Top & Bottom bags produce components of higher quality than our usual system, while having equal operational efficiency. Use of the new bags could result in an important quality improvement in blood components manufacturing.

  2. Comparative assessment of prophylactic transfusions of platelet concentrates obtained by the PRP or buffy-coat methods, in patients undergoing allogeneic hematopoietic stem cell transplantation.

    Science.gov (United States)

    Fernández-Muñoz, Hermógenes; Plaza, Eva M; Rivera-Caravaca, José Miguel; Candela, María José; Romera, Marta; De Arriba, Felipe; Lozano, María L; Vicente, Vicente; Heras, Inmaculada; Castilla-Llorente, Cristina; Rivera, José

    2018-03-27

    Whole blood-derived platelet concentrates can be obtained by the platelet-rich plasma (PRP-PCs) or the buffy-coat (BC-PCs) method. Few studies have shown that BC-PCs display lower in vitro platelet activation, but scarce information exists regarding transfusion efficacy. We have performed a retrospective study assessing platelet transfusion in patients undergoing allogeneic hematopoietic cell transplantation (AHCT) in our clinic, before and after the implementation of BC-PCs. We reviewed clinical records corresponding to 70 PRP-PCs and 86 BC-PCs prophylactic transfusions, which were performed to 55 AHCT patients. Transfusion efficacy was assessed by the 24-h post-transfusion corrected count increment (24-h CCI) and bleeding events. Clinical factors affecting transfusion outcome were also investigated. Clinical characteristics and the total number of platelet transfusions were similar among groups. Mean donor exposure was 5.8 and 5.0 in each single PRP-PCs and BC-PCs transfusion, respectively (p PRP-PCs (8.3[2.7-13.4] vs. 4.7[1.3-8.1]; p PRP-PCs transfusion (HR 4.54; 95% CI 1.72-12.01; p = 0.002). There were no differences between both groups regarding the bleeding events. In the AHCT setting, we hypothesize that BC-PCs transfusion, when compared to PRP-PCs, results in higher CCI and reduced donor exposure, but provides no significant benefit regarding bleeding outcome.

  3. Quality assessment of platelet concentrates prepared by platelet rich plasma-platelet concentrate, buffy coat poor-platelet concentrate (BC-PC and apheresis-PC methods

    Directory of Open Access Journals (Sweden)

    Singh Ravindra

    2009-01-01

    Full Text Available Background: Platelet rich plasma-platelet concentrate (PRP-PC, buffy coat poor-platelet concentrate (BC-PC, and apheresis-PC were prepared and their quality parameters were assessed. Study Design: In this study, the following platelet products were prepared: from random donor platelets (i platelet rich plasma - platelet concentrate (PRP-PC, and (ii buffy coat poor- platelet concentrate (BC-PC and (iii single donor platelets (apheresis-PC by different methods. Their quality was assessed using the following parameters: swirling, volume of the platelet concentrate, platelet count, WBC count and pH. Results: A total of 146 platelet concentrates (64 of PRP-PC, 62 of BC-PC and 20 of apheresis-PC were enrolled in this study. The mean volume of PRP-PC, BC-PC and apheresis-PC was 62.30±22.68 ml, 68.81±22.95 ml and 214.05±9.91 ml and ranged from 22-135 ml, 32-133 ml and 200-251 ml respectively. The mean platelet count of PRP-PC, BC-PC and apheresis-PC was 7.6±2.97 x 1010/unit, 7.3±2.98 x 1010/unit and 4.13±1.32 x 1011/unit and ranged from 3.2-16.2 x 1010/unit, 0.6-16.4 x 1010/unit and 1.22-8.9 x 1011/unit respectively. The mean WBC count in PRP-PC (n = 10, BC-PC (n = 10 and apheresis-PC (n = 6 units was 4.05±0.48 x 107/unit, 2.08±0.39 x 107/unit and 4.8±0.8 x 106/unit and ranged from 3.4 -4.77 x 107/unit, 1.6-2.7 x 107/unit and 3.2 - 5.2 x 106/unit respectively. A total of 26 units were analyzed for pH changes. Out of these units, 10 each were PRP-PC and BC-PC and 6 units were apheresis-PC. Their mean pH was 6.7±0.26 (mean±SD and ranged from 6.5 - 7.0 and no difference was observed among all three types of platelet concentrate. Conclusion: PRP-PC and BC-PC units were comparable in terms of swirling, platelet count per unit and pH. As expected, we found WBC contamination to be less in BC-PC than PRP-PC units. Variation in volume was more in BC-PC than PRP-PC units and this suggests that further standardization is required for preparation of BC

  4. Superior integrin activating capacity and higher adhesion to fibrinogen matrix in buffy coat-derived platelet concentrates (PCs) compared to PRP-PCs.

    Science.gov (United States)

    Beshkar, Pezhman; Hosseini, Ehteramolsadat; Ghasemzadeh, Mehran

    2018-02-01

    Regardless of different sources, methods or devices which are applied for preparation of therapeutic platelets, these products are generally isolated from whole blood by the sedimentation techniques which are based on PRP or buffy coat (BC) separation. As a general fact, platelet preparation and storage are also associated with some deleterious changes that known as platelet storage lesion (PSL). Although these alternations in platelet functional activity are aggravated during storage, whether technical issues within preparation can affect integrin activation and platelet adhesion to fibrinogen were investigated in this study. PRP- and BC-platelet concentrates (PCs) were subjected to flowcytometry analysis to examine the expression of platelet activation marker, P-selectin as well as active confirmation of the GPIIb/IIIa (α IIb β 3 ) on day 0, 1, 3 and 5 post-storage. Platelet adhesion to fibrinogen matrix was evaluated by fluorescence microscopy. Glucose concentration and LDH activity were also measured by colorimetric methods. The increasing P-selectin expression during storage was in a reverse correlation with PAC-1 binding (r = -0.67; p = .001). PRP-PCs showed the higher level of P-selectin expression than BC-PCs, whereas the levels of PAC-1 binding and platelet adhesion to fibrinogen matrix were significantly lower in PRP-PCs. Higher levels of active confirmation of the GPIIb/IIIa in BC-PCs were also associated with greater concentration of glucose in these products. We demonstrated the superior capacities of integrin activation and adhesion to fibrinogen for BC-PCs compared to those of PRP-PCs. These findings may provide more advantages for BC method of platelet preparation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Efficiency of riboflavin and ultraviolet light treatment against high levels of biofilm-derived Staphylococcus epidermidis in buffy coat platelet concentrates.

    Science.gov (United States)

    Taha, M; Culibrk, B; Kalab, M; Schubert, P; Yi, Q-L; Goodrich, R; Ramirez-Arcos, S

    2017-07-01

    Staphylococcus epidermidis forms surface-attached aggregates (biofilms) in platelet concentrates (PCs), which are linked to missed detection during PC screening. This study was aimed at evaluating the efficacy of riboflavin-UV treatment to inactivate S. epidermidis biofilms in buffy coat (BC) PCs. Biofilm and non-biofilm cells from S. epidermidis ST-10002 and S. epidermidis AZ-66 were individually inoculated into whole blood (WB) units (~10 6 colony-forming units (CFU)/ml) (N = 4-5). One spiked and three unspiked WB units were processed to produce a BC-PC pool. Riboflavin was added to the pool which was then split into two bags: one for UV treatment and the second was untreated. Bacterial counts were determined before and after treatment. In vitro PC quality was assessed by flow cytometry and dynamic light scattering. Bacterial counts were reduced during BC-PC production from ~10 6 CFU/ml in WB to 10 3 -10 4 CFU/ml in PCs (P Riboflavin-UV treatment resulted in significantly higher reduction of S. epidermidis AZ-66 than strain ST-10002 (≥3·5 log reduction and 2·6-2·8 log reduction, respectively, P 0·05). Platelet activation was enhanced in PCs produced with WB inoculated with biofilms compared to non-biofilm cells (P Riboflavin-UV treatment was similarly efficacious in PCs produced from WB inoculated with S. epidermidis biofilm or non-biofilm cells. Levels of biofilm-derived S. epidermidis ≥10 3 CFU/ml were not completely inactivated; however, further testing is necessary with lower (real-life) bacterial levels. © 2017 International Society of Blood Transfusion.

  6. Differences in levels of platelet-derived microparticles in platelet components prepared using the platelet rich plasma, buffy coat, and apheresis procedures.

    Science.gov (United States)

    Noulsri, Egarit; Udomwinijsilp, Prapaporn; Lerdwana, Surada; Chongkolwatana, Viroje; Permpikul, Parichart

    2017-04-01

    There has been an increased interest in platelet-derived microparticles (PMPs) in transfusion medicine. Little is known about PMP status during the preparation of platelet concentrates for transfusion. The aim of this study is to compare the PMP levels in platelet components prepared using the buffy coat (BC), platelet-rich plasma platelet concentrate (PRP-PC), and apheresis (AP) processes. Platelet components were prepared using the PRP-PC and BC processes. Apheresis platelets were prepared using the Trima Accel and Amicus instruments. The samples were incubated with annexin A5-FITC, CD41-PE, and CD62P-APC. At day 1 after processing, the PMPs and activated platelets were determined using flow cytometry. Both the percentage and number of PMPs were higher in platelet components prepared using the Amicus instrument (2.6±1.8, 32802±19036 particles/μL) than in platelet components prepared using the Trima Accel instrument (0.5±0.4, 7568±5298 particles/μL), BC (1.2±0.6, 12,920±6426 particles/μL), and PRP-PC (0.9±0.6, 10731±5514 particles/μL). Both the percentage and number of activated platelets were higher in platelet components prepared using the Amicus instrument (33.2±13.9, 427553±196965 cells/μL) than in platelet components prepared using the Trima Accel instrument (16.2±6.1, 211209±87706 cells/μL), BC (12.9±3.2, 140624±41003 cells/μL), and PRP-PC (21.1±6.3, 265210±86257 cells/μL). The study suggests high variability of PMPs and activated platelets in platelet components prepared using different processes. This result may be important in validating the instruments involved in platelet blood collection and processing. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Detection and characterisation of trypanosome strains supposedly resistant to trypanocidal drugs in Senegal; Detection au buffy coat technique et en ELISA de souches de trypanosomes supposees chimioresistantes au Senegal et caracterisation therapeutique

    Energy Technology Data Exchange (ETDEWEB)

    Diaite, A; Seye, M; Mane, A; Ndiaye, T; Seye, M M [Institut Senegalais de Recherches Agricoles (ISRA), Dakar (Senegal). Lab. de Parasitologie

    1997-02-01

    In the region of Sokone cattle are constantly exposed to infections with trypanosomes transmitted by Glossina morsitans submorsitans and G. palpalis gambiensis. Trypanocidal drugs are widely used by the farmers on the 50,000 cattle present in the region. Consequently, drug resistance has become a major problem. During the present study goats were inoculated with trypanosome strains isolated from infected cattle. Following the appearance of parasitaemia, the animals were treated with either Berenil, Samorin or Ethidium. The results indicated the parasites were susceptible to Samorin, but one of the Trypanosoma vivax strains showed resistance to Berenil and Ethidium. In addition, the performance of the antigen detection ELISA was compared with that of the Buffy Coat Technique using more than 1000 serum samples from the Sokone region and 100 samples from Northern Senegal infested with tsetse flies. The results showed a very high specificity of 98%. However, additional tests will be necessary to assess the sensitivity properly. (author). 3 refs, 7 tabs.

  8. Storage of Buffy-coat-derived platelets in additive solutions: in vitro effects on platelets prepared by the novel TACSI system and stored in plastic containers with different gas permeability.

    Science.gov (United States)

    Sandgren, P; Hild, M; Sjödin, A; Gulliksson, H

    2010-11-01

    The novel TACSI system is designed for automated preparation of platelets (PLTs) from pooled buffy coats (BCs). One TACSI device will handle 6 units at the same time. The aim of our in vitro study is to investigate the effects of using this automated equipment with subsequent storage in two different plastic containers and to compare these results with PLTs prepared by the OrbiSac system. Buffy-coat-derived PLTs (n=8) were prepared by using the TACSI system, including storage in polyvinyl chloride (PVC)-based plastic containers with di, n-decyl phthalate (DnDP) (TACSI R) and BTHC (TACSI T)-based plasticizers. As a reference, the OrbiSac System was used to prepare PLTs (n=8) with subsequent storage in a PVC plastic container with a citrate-based plasticizer (BTHC). In total, 16 TACSI and eight reference units, supplied by approximately 30% plasma and 70% SSP+, were analysed for various in vitro variables during the 7-day storage period. No significant difference in PLT counts, LDH, mean platelet volume (MPV) and adenosine triphosphate between the groups was detected. Glucose was lower (P6·8 (day 7) and swirling remained at the highest level (score=2) for all units throughout storage. Platelets prepared by the TACSI system with subsequent storage in two different PVC-based plastic containers were equivalent to reference PLTs with regard to in vitro characteristics during 7 days of storage. © 2010 The Author(s). Vox Sanguinis © 2010 International Society of Blood Transfusion.

  9. Isolation of human monocytes by double gradient centrifugation and their differentiation to macrophages in teflon-coated cell culture bags.

    Science.gov (United States)

    Menck, Kerstin; Behme, Daniel; Pantke, Mathias; Reiling, Norbert; Binder, Claudia; Pukrop, Tobias; Klemm, Florian

    2014-09-09

    Human macrophages are involved in a plethora of pathologic processes ranging from infectious diseases to cancer. Thus they pose a valuable tool to understand the underlying mechanisms of these diseases. We therefore present a straightforward protocol for the isolation of human monocytes from buffy coats, followed by a differentiation procedure which results in high macrophage yields. The technique relies mostly on commonly available lab equipment and thus provides a cost and time effective way to obtain large quantities of human macrophages. Briefly, buffy coats from healthy blood donors are subjected to a double density gradient centrifugation to harvest monocytes from the peripheral blood. These monocytes are then cultured in fluorinated ethylene propylene (FEP) Teflon-coated cell culture bags in the presence of macrophage colony-stimulating factor (M-CSF). The differentiated macrophages can be easily harvested and used for subsequent studies and functional assays. Important methods for quality control and validation of the isolation and differentiation steps will be highlighted within the protocol. In summary, the protocol described here enables scientists to routinely and reproducibly isolate human macrophages without the need for cost intensive tools. Furthermore, disease models can be studied in a syngeneic human system circumventing the use of murine macrophages.

  10. Utilisation of the buffy coat technique and an antibody-detection ELISA as tools for assessing the impact of trypanosomosis on health and productivity of N'Dama cattle

    International Nuclear Information System (INIS)

    Faye, J.A.; Mattioli, R.C.

    2000-01-01

    The buffy coat technique (BCT), a parasitological test, and an indirect antibody ELISA (Ab-ELISA) were used to detect trypanosome infections in blood and serum samples, respectively, collected on N'Dama cattle exposed to natural high tsetse challenge. These two diagnostic tools were also utilized to assess trypanosomal status in sequentially collected blood and serum samples from two groups composed of 5 N'Dama cattle each experimentally challenged with Trypanosoma congolense and T. vivax, In both studies, packed red cell volume (PCV) and live weight were measured. The specificity of the Ab-ELISA was computed by testing approximately 70 serum samples obtained from a cattle population kept under zero tsetse challenge. The specificity was found to be 95.8% for T. vivax and 97. 1 % for T. congolense. In the field study, 3.9% (12/310) of blood samples was parasitologically positive. In corresponding serum samples the prevalence of positive trypanosome sero-reactors was 54.8% (170/310). However, antibodies against trypanosomes persisted in serum when blood samples were no longer parasitologically positive. In both blood and serum samples, T. vivax was found to be the main infecting species. The sensitivity of the Ab-ELISA for T. vivax was 81.8%. Due to the extremely low numbers of T. congolense infection (only one), as detected by BCT, the sensitivity for that trypanosome species was not computed. In the experimentally challenged cattle, 80% (24/30) and 33.3% (10/30) of blood samples were BCT positive for T. congolense and T. vivax, respectively. Antibodies in corresponding sera were present in 69% (20/29) and 96.3% (26/27) of animals challenged with T. congolense and T. vivax, respectively. The serological assay for T. congolense antibody detection exhibited high cross-reactivity with T. vivax antigens, as assessed in sera collected from T. vivax infected animals. In the field study, cattle showing the presence of antibodies against T. congolense and/or T. vivax had

  11. A simple method for human peripheral blood monocyte Isolation

    Directory of Open Access Journals (Sweden)

    Marcos C de Almeida

    2000-04-01

    Full Text Available We describe a simple method using percoll gradient for isolation of highly enriched human monocytes. High numbers of fully functional cells are obtained from whole blood or buffy coat cells. The use of simple laboratory equipment and a relatively cheap reagent makes the described method a convenient approach to obtaining human monocytes.

  12. Eosinophil protein X/eosinophil derived neurotoxin (EPX/EDN). Detection by enzyme-linked immunosorbent assay and purification from normal human urine

    DEFF Research Database (Denmark)

    Reimert, C M; Minuva, U; Kharazmi, A

    1991-01-01

    Eosinophil protein X/eosinophil derived neurotoxin (EPX/EDN) is one of the cationic proteins found in the granules of the human eosinophilic granulocytes. EPX was purified from extracts of granules isolated from blood buffy coat cells of healthy donors. Polyclonal anti-EPX antibodies were...

  13. Polysaccharide coating of human corneal endothelium

    DEFF Research Database (Denmark)

    Schroder, H D; Sperling, S

    1977-01-01

    Electron microscopy revealed the presence of a 600-1500 A thick layer of polysaccharide on the surface of human corneal endothelial cells. The surface layer was visualized by combined fixation and staining in a mixture of ruthenium red and osmium tetroxide. The coating material was stable for at ...... for at least 39 h post mortem and was retained on disintegrating cells....

  14. Buffy the Vampire Slayer: A Superheroine, but not in Serbia

    Directory of Open Access Journals (Sweden)

    Ljiljana Gavrilović

    2016-02-01

    Full Text Available This paper discusses the television series Buffy the Vampire Slayer, more specifically, its enormous popularity in the United States, Western Europe and Australia, and the absence of any reaction to the series in Serbia. By comparing themes regarded as important in western societies to the current situation in Serbia, the analysis shows that Buffy the Vampire Slayer is a series that could not have gained popularity in Serbia because it uses the language of fantasy to speak about reality and pose unpleasant questions, which the Serbian public does not wish to hear.

  15. Estudo do método da extração da camada leucoplaquetária na produção de hemocomponentes: avaliação laboratorial A study of the Buffy-coat extraction method for blood component processing: laboratorial analysis

    Directory of Open Access Journals (Sweden)

    Mario I. Serinolli

    2004-01-01

    Full Text Available Dentre os métodos para a obtenção de hemocomponentes destaca-se o método do plasma rico em plaquetas (PRP e o método da extração da camada leucoplaquetária (ECLP. Este estudo tem por objetivo comparar os métodos do PRP e da ECLP na produção de hemocomponentes. Foram processadas 88 bolsas de sangue total (ST pelo método do PRP, 130 bolsas triplas pelo método da ECLP (ECLPT e 215 bolsas coletadas em bolsas quádruplas pelo método da ECLP (ECLPQ com o uso de extrator automático. Encontramos diferença estatisticamente significante na quantidade de Hb total /unidade entre ECLPT e ECLPQ (p=0,005 e entre ECLPT e PRP (p=0,007 no ST. Houve diferença estatisticamente entre ECLPT e ECLPQ (pThe most commonly used methods for blood component processing are the "plasma rich in platelets method" (PRP, and the Buffy-coat extraction method (BC.The purpose of this study was to compare these two methods in the processing of blood components. Eighty-eight whole blood units (WB were processed by the PRP method, 130 blood units were processed by the BC triple blood bag method (BCT and 215 blood units were collected in quadruple blood bags by the BC method (BCQ using an automatic extractor. A statistically significant difference was observed in the number in the total Hb per unit of WB between the BCT and BCQ methods (p=0.005 and between the BCT and PRP methods (p=0.007. There were also statistically significant differences between the BCT and BCQ methods (p<0.001 and between BCQ and PRP methods (p<0.001 in relation to leukocytes/mL. In the RBC concentrates, we found statistically significant differences between the PRP method and both the BCT and BCQ methods in respect to hematocrit levels, Hb recovery, total Hb, leukocytes, leukocyte depletion, platelets and platelet depletion (p<0.001 in all cases. We also found statistically significant differences between the PRP, BCT and BCQ methods for the volume, platelet recovery, and leukocyte depletion (p<0

  16. HSV-1-induced chemokine expression via IFI16-dependent and IFI16-independent pathways in human monocyte-derived macrophages

    DEFF Research Database (Denmark)

    Søby, Stine; Laursen, Rune R; Østergaard, Lars Jørgen

    2012-01-01

    ABSTRACT: BACKGROUND: Innate recognition is essential in the antiviral response against infection by herpes simplex virus (HSV). Chemokines are important for control of HSV via recruitment of natural killer cells, T lymphocytes, and antigen-presenting cells. We previously found that early HSV-1......-mediated chemokine responses are not dependent on TLR2 and TLR9 in human macrophages. Here, we investigated the role of the recently identified innate IFN-inducible DNA receptor IFI16 during HSV-1 infection in human macrophages. METHODS: Peripheral blood mononuclear cells were purified from buffy coats...

  17. The Last Gender Picture Show to Closure Buffy the Vampire Slayer

    Directory of Open Access Journals (Sweden)

    Sven Grampp

    2016-03-01

    Full Text Available This work presents in (and especially on one detail what it means to practice gender analysis as formal image analysis in the context of television shows. The chosen example for that is the closing scene of “Buffy the Vampire Slayer” (USA 1997-2003. This television show engages in a highly self-reflexive manner with common pop cultural representations of gender, which becomes particularly prevalent and radically condensed in the series finale.

  18. Growth factors--BMPs, DBMs, and buffy coat products: are there any proven differences amongst them?

    Science.gov (United States)

    Veillette, Christian J H; McKee, Michael D

    2007-03-01

    Advances in the understanding of bone repair and improved biotechnology have led to the introduction of new strategies for orthopedic surgeons to control and modulate bone healing using growth factors. However, many orthopedic surgeons are uncertain about the current levels of evidence supporting the use of materials that possess these properties and their therapeutic role in the management of skeletal problems such as fracture, long-bone nonunion, and spine fusion. In particular, the differences amongst osteoinductive factors synthesized by recombinant gene technology, or derived from demineralized bone matrix or platelet rich plasma requires clarification.

  19. Preparation of leukodepleted platelet concentrates from pooled buffy coats: prestorage filtration with Autostop BC

    NARCIS (Netherlands)

    Pietersz, R. N.; van der Meer, P. F.; Steneker, I.; Hinloopen, B.; Dekker, W. J.; van Zanten, A. P.; Reesink, H. W.

    1999-01-01

    BACKGROUND AND OBJECTIVES: Our requirements for leukocyte-depleted platelet concentrates (LD-PC) for an adult patient are: platelets >240x10(9), leukocytes <5x10(6), volume of 150-400 ml; and at the end of storage a pH between 6.8 and 7.4 and presence of the swirling effect. Our aim was to develop a

  20. Biodegradable electrospun nanofibers coated with platelet-rich plasma for cell adhesion and proliferation

    International Nuclear Information System (INIS)

    Diaz-Gomez, Luis; Alvarez-Lorenzo, Carmen; Concheiro, Angel; Silva, Maite; Dominguez, Fernando; Sheikh, Faheem A.; Cantu, Travis; Desai, Raj; Garcia, Vanessa L.; Macossay, Javier

    2014-01-01

    Biodegradable electrospun poly(ε-caprolactone) (PCL) scaffolds were coated with platelet-rich plasma (PRP) to improve cell adhesion and proliferation. PRP was obtained from human buffy coat, and tested on human adipose-derived mesenchymal stem cells (MSCs) to confirm cell proliferation and cytocompatibility. Then, PRP was adsorbed on the PCL scaffolds via lyophilization, which resulted in a uniform sponge-like coating of 2.85 (S.D. 0.14) mg/mg. The scaffolds were evaluated regarding mechanical properties (Young's modulus, tensile stress and tensile strain), sustained release of total protein and growth factors (PDGF-BB, TGF-β1 and VEGF), and hemocompatibility. MSC seeded on the PRP–PCL nanofibers showed an increased adhesion and proliferation compared to pristine PCL fibers. Moreover, the adsorbed PRP enabled angiogenesis features observed as neovascularization in a chicken chorioallantoic membrane (CAM) model. Overall, these results suggest that PRP–PCL scaffolds hold promise for tissue regeneration applications. - Highlights: • Platelet-rich plasma (PRP) can be adsorbed on electrospun fibers via lyophilization. • PRP coating enhanced mesenchymal stem cell adhesion and proliferation on scaffolds. • PRP-coated scaffolds showed sustained release of growth factors. • Adsorbed PRP provided angiogenic features. • PRP-poly(ε-caprolactone) scaffolds hold promise for tissue regeneration applications

  1. Biodegradable electrospun nanofibers coated with platelet-rich plasma for cell adhesion and proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Diaz-Gomez, Luis [Departamento de Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Universidad de Santiago de Compostela, 15872 Santiago de Compostela (Spain); Instituto de Ortopedia y Banco de Tejidos Musculoesqueléticos, Universidad de Santiago de Compostela, 15872 Santiago de Compostela (Spain); Alvarez-Lorenzo, Carmen, E-mail: carmen.alvarez.lorenzo@usc.es [Departamento de Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Universidad de Santiago de Compostela, 15872 Santiago de Compostela (Spain); Concheiro, Angel [Departamento de Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Universidad de Santiago de Compostela, 15872 Santiago de Compostela (Spain); Silva, Maite [Instituto de Ortopedia y Banco de Tejidos Musculoesqueléticos, Universidad de Santiago de Compostela, 15872 Santiago de Compostela (Spain); Dominguez, Fernando [Fundación Publica Galega de Medicina Xenómica, Santiago de Compostela (Spain); Sheikh, Faheem A.; Cantu, Travis; Desai, Raj; Garcia, Vanessa L. [Department of Chemistry, University of Texas Pan American, Edinburg, TX 78541 (United States); Macossay, Javier, E-mail: jmacossay@utpa.edu [Department of Chemistry, University of Texas Pan American, Edinburg, TX 78541 (United States)

    2014-07-01

    Biodegradable electrospun poly(ε-caprolactone) (PCL) scaffolds were coated with platelet-rich plasma (PRP) to improve cell adhesion and proliferation. PRP was obtained from human buffy coat, and tested on human adipose-derived mesenchymal stem cells (MSCs) to confirm cell proliferation and cytocompatibility. Then, PRP was adsorbed on the PCL scaffolds via lyophilization, which resulted in a uniform sponge-like coating of 2.85 (S.D. 0.14) mg/mg. The scaffolds were evaluated regarding mechanical properties (Young's modulus, tensile stress and tensile strain), sustained release of total protein and growth factors (PDGF-BB, TGF-β1 and VEGF), and hemocompatibility. MSC seeded on the PRP–PCL nanofibers showed an increased adhesion and proliferation compared to pristine PCL fibers. Moreover, the adsorbed PRP enabled angiogenesis features observed as neovascularization in a chicken chorioallantoic membrane (CAM) model. Overall, these results suggest that PRP–PCL scaffolds hold promise for tissue regeneration applications. - Highlights: • Platelet-rich plasma (PRP) can be adsorbed on electrospun fibers via lyophilization. • PRP coating enhanced mesenchymal stem cell adhesion and proliferation on scaffolds. • PRP-coated scaffolds showed sustained release of growth factors. • Adsorbed PRP provided angiogenic features. • PRP-poly(ε-caprolactone) scaffolds hold promise for tissue regeneration applications.

  2. Cultivation of human dermal fibroblasts and epidermal keratinocytes on keratin-coated silica bead substrates.

    Science.gov (United States)

    Tan, Bee Yi; Nguyen, Luong T H; Kim, Hyo-Sop; Kim, Jae-Ho; Ng, Kee Woei

    2017-10-01

    Human hair keratin is promising as a bioactive material platform for various biomedical applications. To explore its versatility further, human hair keratin was coated onto monolayers of silica beads to produce film-like substrates. This combination was hypothesized to provide a synergistic effect in improving the biochemical properties of the resultant composite. Atomic force microscopy analysis showed uniform coatings of keratin on the silica beads with a slight increase in the resulting surface roughness. Keratin-coated silica beads had higher surface energy and relatively lower negative charge than those of bare silica beads. To investigate cell response, human dermal fibroblasts (HDFs), and human epidermal keratinocytes (HEKs) were cultured on the substrates over 4 days. Results showed that keratin coatings significantly enhanced the metabolic activity of HDFs and encouraged cell spreading but did not exert any significant effects on HEKs. HDF expression of collagen I was significantly more intense on the keratin-coated compared to the bare silica substrates. Furthermore, HDF secretion of various cytokines suggested that keratin coatings triggered active cell responses related to wound healing. Collectively, our study demonstrated that human hair keratin-coated silica bead monolayers have the potential to modulate HDF behavior in culture and may be exploited further. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2789-2798, 2017. © 2017 Wiley Periodicals, Inc.

  3. Taking a bite out of "Buffy": Carnivalesque play and resistance in fan fiction

    Directory of Open Access Journals (Sweden)

    Amanda L. Hodges

    2011-09-01

    Full Text Available Popular culture provides a vital point of entry to examine discourses of hegemony and resistance at work within the growing culture of fandom. Drawing from epistemologies of feminism and poststructuralism, we deconstruct how fans read, co-construct, apply, and reenvision texts as they navigate societal notions of gender in their own constructions of subjectivity. We discuss subversive examples of sexuality and gender found in American popular culture, particularly the portrayal of femininity in the character of Faith, the bad girl from Buffy the Vampire Slayer. Such examples are important because they impart crucial hegemonic lessons that may then be played out in everyday life. By focusing on the third season of Buffy the Vampire Slayer, we examine the discourses of risk at play within the source text, fan sites, and online fan fiction. Bakhtin's ideas of carnival drive much of fan fiction, and Foucault's analysis of power relations as well as Butler's theories of performativity contribute to play that affords dynamic, critical perspectives with which to interrogate social metanarratives and their impact on the subject.

  4. Coating independent cytotoxicity of citrate- and PEG-coated silver nanoparticles on a human hepatoma cell line.

    Science.gov (United States)

    Bastos, Verónica; Ferreira-de-Oliveira, José M P; Carrola, Joana; Daniel-da-Silva, Ana L; Duarte, Iola F; Santos, Conceição; Oliveira, Helena

    2017-01-01

    The antibacterial potential of silver nanoparticles (AgNPs) resulted in their increasing incorporation into consumer, industrial and biomedical products. Therefore, human and environmental exposure to AgNPs (either as an engineered product or a contaminant) supports the emergent research on the features conferring them different toxicity profiles. In this study, 30nm AgNPs coated with citrate or poly(ethylene glycol) (PEG) were used to assess the influence of coating on the effects produced on a human hepatoma cell line (HepG2), namely in terms of viability, apoptosis, apoptotic related genes, cell cycle and cyclins gene expression. Both types of coated AgNPs decreased cell proliferation and viability with a similar toxicity profile. At the concentrations used (11 and 5μg/mL corresponding to IC50 and ~IC10 levels, respectively) the amount of cells undergoing apoptosis was not significant and the apoptotic related genes BCL2 (anti-apoptotic gene) and BAX (pro-apoptotic gene) were both downregulated. Moreover, both AgNPs affected HepG2 cell cycle progression at the higher concentration (11μg/mL) by increasing the percentage of cells in S (synthesis phase) and G2 (Gap 2 phase) phases. Considering the cell-cycle related genes, the expression of cyclin B1 and cyclin E1 genes were decreased. Thus, this work has shown that citrate- and PEG-coated AgNPs impact on HepG2 apoptotic gene expression, cell cycle dynamics and cyclin regulation in a similar way. More research is needed to determine the properties that confer AgNPs at lower toxicity, since their use has proved helpful in several industrial and biomedical contexts. Copyright © 2016. Published by Elsevier B.V.

  5. Micro/Nano Structural Tantalum Coating for Enhanced Osteogenic Differentiation of Human Bone Marrow Stem Cells

    OpenAIRE

    Ding Ding; Youtao Xie; Kai Li; Liping Huang; Xuebin Zheng

    2018-01-01

    Recently, tantalum has been attracting much attention for its anticorrosion resistance and biocompatibility, and it has been widely used in surface modification for implant applications. To improve its osteogenic differentiation of human bone marrow stem cells (hBMSCs), a micro/nano structure has been fabricated on the tantalum coating surface through the combination of anodic oxidation and plasma spraying method. The morphology, composition, and microstructure of the modified coating were co...

  6. A loss of Pdxk model of Parkinson disease in Drosophila can be suppressed by Buffy.

    Science.gov (United States)

    M'Angale, P Githure; Staveley, Brian E

    2017-06-12

    The identification of a DNA variant in pyridoxal kinase (Pdxk) associated with increased risk to Parkinson disease (PD) gene led us to study the inhibition of this gene in the Dopa decarboxylase (Ddc)-expressing neurons of the well-studied model organism Drosophila melanogaster. The multitude of biological functions attributable to the vitamers catalysed by this kinase reveal an overabundance of possible links to PD, that include dopamine synthesis, antioxidant activity and mitochondrial function. Drosophila possesses a single homologue of Pdxk and we used RNA interference to inhibit the activity of this kinase in the Ddc-Gal4-expressing neurons. We further investigated any association between this enhanced disease risk gene with the established PD model induced by expression of α-synuclein in the same neurons. We relied on the pro-survival functions of Buffy, an anti-apoptotic Bcl-2 homologue, to rescue the Pdxk-induced phenotypes. To drive the expression of Pdxk RNA interference in DA neurons of Drosophila, we used Ddc-Gal4 which drives expression in both dopaminergic and serotonergic neurons, to result in decreased longevity and compromised climbing ability, phenotypes that are strongly associated with Drosophila models of PD. The inhibition of Pdxk in the α-synuclein-induced Drosophila model of PD did not alter longevity and climbing ability of these flies. It has been previously shown that deficiency in vitamers lead to mitochondrial dysfunction and neuronal decay, therefore, co-expression of Pdxk-RNAi with the sole pro-survival Bcl-2 homologue Buffy in the Ddc-Gal4-expressing neurons, resulted in increased survival and a restored climbing ability. In a similar manner, when we inhibited Pdxk in the developing eye using GMR-Gal4, we found that there was a decrease in the number of ommatidia and the disruption of the ommatidial array was more pronounced. When Pdxk was inhibited with the α-synuclein-induced developmental eye defects, the eye phenotypes were

  7. Individual differences in the radiosensitivity of hematopoietic progenitor cells detected in steady-state human peripheral blood

    International Nuclear Information System (INIS)

    Oriya, Asami; Takahashi, Kenji; Kashiwakura, Ikuo; Inanami, Osamu; Kuwabara, Mikinori; Miura, Toshiaki; Abe, Yoshinao

    2008-01-01

    The aim of this study is to evaluate the individual differences in radiosensitivity of lineage-committed myeloid hematopoietic progenitors, colony-forming cells (CFC), detected in steady-state human peripheral blood (PB). Mononuclear cells were prepared from the buffy-coat of 30 individuals PB, and were assayed for CFC by semi-solid culture supplemented with cytokines. X irradiation was performed in the range of 0.5-4 Gy at a dose rate of about 80 cGy/min. The mean number of hematopoietic progenitor cells is 5866±3408 in 1 ml of buffy-coat, suggesting that the erythroid progenitor cells are the major population. The total CFC radiosensitivity parameter D 0 and n value are 1.18±0.24 and 1.89±0.98, respectively. Using a linear regression analysis, a statistically significant correlation is observed between the D 0 value and the surviving fraction at 4 Gy (r=0.611 p 0 parameter and the level of antioxidants, plasma uric acid, plasma bilirubin, and intracellular glutathione. The present study demonstrates that there are large individual differences in the radiosensitivity of hematopoietic progenitor cells as detected in steady-state human PB. These differences demonstrate almost no correlation with plasma or intracellular antioxidants. The prediction of individual differences in radiosensitivity of CFC can only be measured by 4 Gy irradiation. (author)

  8. Behavior of Human Bone Marrow-Derived Mesenchymal Stem Cells on Various Titanium-Based Coatings

    Directory of Open Access Journals (Sweden)

    Chengjuan Qu

    2016-10-01

    Full Text Available The chemical composition and texture of titanium coatings can influence the growth characteristics of the adhered cells. An enhanced proliferation of the human mesenchymal stem cells (hMSCs would be beneficial. The present study was aimed to investigate whether titanium deposited at different atmospheres would affect the cell growth properties, cellular morphology, and expression of surface markers of hMSCs. Titanium-based coatings were deposited on silicon wafers under oxygen, nitrogen, or argon atmospheres by ultra-short pulsed laser deposition using two different gas pressures followed by heating at 400 °C for 2 h. The characteristics of the coated surfaces were determined via contact angle, zeta potential, and scanning electron microscopy (SEM techniques. Human MSCs were cultivated on differently coated silicon wafers for 48 h. Subsequently, the cell proliferation rates were analyzed with an MTT assay. The phenotype of hMSCs was checked via immunocytochemical stainings of MSC-associated markers CD73, CD90, and CD105, and the adhesion, spreading, and morphology of hMSCs on coated materials via SEM. The cell proliferation rates of the hMSCs were similar on all coated silicon wafers. The hMSCs retained the MSC phenotype by expressing MSC-associated markers and fibroblast-like morphology with cellular projections. Furthermore, no significant differences could be found in the size of the cells when cultured on all various coated surfaces. In conclusion, despite certain differences in the contact angles and the zeta potentials of various titanium-based coatings, no single coating markedly improved the growth characteristics of hMSCs.

  9. Micro/Nano Structural Tantalum Coating for Enhanced Osteogenic Differentiation of Human Bone Marrow Stem Cells.

    Science.gov (United States)

    Ding, Ding; Xie, Youtao; Li, Kai; Huang, Liping; Zheng, Xuebin

    2018-04-03

    Recently, tantalum has been attracting much attention for its anticorrosion resistance and biocompatibility, and it has been widely used in surface modification for implant applications. To improve its osteogenic differentiation of human bone marrow stem cells (hBMSCs), a micro/nano structure has been fabricated on the tantalum coating surface through the combination of anodic oxidation and plasma spraying method. The morphology, composition, and microstructure of the modified coating were comprehensively studied by employing scanning electron microscopy (SEM), X-ray diffraction (XRD) as well as transmission electron microscopy (TEM). The effects of hierarchical structures as well as micro-porous structure of tantalum coating on the behavior for human bone marrow stem cells (hBMSCs) were evaluated and compared at both cellular and molecular levels in vitro. The experimental results show that a hierarchical micro/nano structure with Ta₂O₅ nanotubes spread onto a micro-scale tantalum coating has been fabricated successfully, which is confirmed to promote cell adhesion and spreading. Besides, the hierarchical micro/nano tantalum coating can provide 1.5~2.1 times improvement in gene expression, compared with the micro-porous tantalum coating. It demonstrates that it can effectively enhance the proliferation and differentiation of hBMSCs in vitro.

  10. Micro/Nano Structural Tantalum Coating for Enhanced Osteogenic Differentiation of Human Bone Marrow Stem Cells

    Directory of Open Access Journals (Sweden)

    Ding Ding

    2018-04-01

    Full Text Available Recently, tantalum has been attracting much attention for its anticorrosion resistance and biocompatibility, and it has been widely used in surface modification for implant applications. To improve its osteogenic differentiation of human bone marrow stem cells (hBMSCs, a micro/nano structure has been fabricated on the tantalum coating surface through the combination of anodic oxidation and plasma spraying method. The morphology, composition, and microstructure of the modified coating were comprehensively studied by employing scanning electron microscopy (SEM, X-ray diffraction (XRD as well as transmission electron microscopy (TEM. The effects of hierarchical structures as well as micro-porous structure of tantalum coating on the behavior for human bone marrow stem cells (hBMSCs were evaluated and compared at both cellular and molecular levels in vitro. The experimental results show that a hierarchical micro/nano structure with Ta2O5 nanotubes spread onto a micro-scale tantalum coating has been fabricated successfully, which is confirmed to promote cell adhesion and spreading. Besides, the hierarchical micro/nano tantalum coating can provide 1.5~2.1 times improvement in gene expression, compared with the micro-porous tantalum coating. It demonstrates that it can effectively enhance the proliferation and differentiation of hBMSCs in vitro.

  11. Titania-polymeric powder coatings with nano-topography support enhanced human mesenchymal cell responses.

    Science.gov (United States)

    Mozumder, Mohammad Sayem; Zhu, Jesse; Perinpanayagam, Hiran

    2012-10-01

    Titanium implant osseointegration is dependent on the cellular response to surface modifications and coatings. Titania-enriched nanocomposite polymeric resin coatings were prepared through the application of advanced ultrafine powder coating technology. Their surfaces were readily modified to create nano-rough (topographies that supported human embryonic palatal mesenchymal cell responses. Energy dispersive x-ray spectroscopy confirmed continuous and homogenous coatings with a similar composition and even distribution of titanium. Scanning electron microscopy (SEM) showed complex micro-topographies, and atomic force microscopy revealed intricate nanofeatures and surface roughness. Cell counts, mitochondrial enzyme activity reduction of yellow 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) to dark purple, SEM, and inverted fluorescence microscopy showed a marked increase in cell attachment, spreading, proliferation, and metabolic activity on the nanostructured surfaces. Reverse Transcription- Polymerase Chain Reaction (RT-PCR) analysis showed that type I collagen and Runx2 expression were induced, and Alizarin red staining showed that mineral deposits were abundant in the cell cultures grown on nanosurfaces. This enhancement in human mesenchymal cell attachment, growth, and osteogenesis were attributed to the nanosized surface topographies, roughness, and moderate wetting characteristics of the coatings. Their dimensional similarity to naturally occurring matrix proteins and crystals, coupled with their increased surface area for protein adsorption, may have facilitated the response. Therefore, this application of ultrafine powder coating technology affords highly biocompatible surfaces that can be readily modified to accentuate the cellular response. Copyright © 2012 Wiley Periodicals, Inc.

  12. Surface coatings on quartz grains in bentonites and their relevance to human health

    International Nuclear Information System (INIS)

    Wendlandt, Richard F.; Harrison, Wendy J.; Vaughan, David J.

    2007-01-01

    The cytotoxicity of quartz in the human lung is recognized to be dependent on both the inherent properties of the silica dust and external factors related to the history of the dust and including the presence of surface contamination. In this study, the physical and chemical surface properties of quartz grains in commercial bentonite deposits from the western (South Dakota) and southern (Alabama) USA were investigated. Measured quartz contents of bentonites range from 1.9 to 8.5 wt% with the <10 μm size fraction comprising 6-45% of this total. Trace element contents (Fe-Ti-Al) of quartz grains from any given bentonite are similar, indicating a single origin for the quartz with little if any contamination from other sources. Surface coatings are pervasive on all quartz grains and resist removal by repeated vigorous washings and reaction with HCl. Textural attributes and XPS and EDS analyses of these coatings are consistent with most being montmorillonite and, less frequently, mixtures of montmorillonite and opaline silica. Opaline silica (opal-A and opal-CT) occurs in two texturally distinct generations: an early massive grain-coating event and as later lepispheres. Montmorillonite coating thicknesses range from <1 μm to more than 10 μm thick. Surfaces of plagioclase, K-feldspar, and biotite grains are conspicuously devoid of montmorillonite coatings, but may show sparse distributions of opal-CT lepispheres. HRTEM has not confirmed a topotactic relationship or atomic structural concordance between montmorillonite coatings and underlying quartz grains. Alternatively, a precursor volcanic glass phase that coats the quartz surfaces during volcanic eruption and/or preferential early precipitation of opaline silica on quartz may provide substrates for development of montmorillonite coatings. Estimations of montmorillonite biodurability under pulmonary pH conditions suggest possible prolonged sequestration of respired bentonite quartz grains from contact with lung

  13. Interaction of human mesenchymal stem cells with osteopontin coated hydroxyapatite surfaces

    DEFF Research Database (Denmark)

    Jensen, Thomas; Dolatshahi-Pirouz, Alireza; Foss, Morten

    2010-01-01

    In vitro studies of the initial attachment, spreading and motility of human bone mesenchymal stem cells have been carried out on bovine osteopontin (OPN) coated hydroxyapatite (HA) and gold (Au) model surfaces. The adsorption of OPN extracted from bovine milk was monitored by the quartz crystal...

  14. Glucose-coated gold nanoparticles transfer across human brain endothelium and enter astrocytes in vitro.

    Directory of Open Access Journals (Sweden)

    Radka Gromnicova

    Full Text Available The blood-brain barrier prevents the entry of many therapeutic agents into the brain. Various nanocarriers have been developed to help agents to cross this barrier, but they all have limitations, with regard to tissue-selectivity and their ability to cross the endothelium. This study investigated the potential for 4 nm coated gold nanoparticles to act as selective carriers across human brain endothelium and subsequently to enter astrocytes. The transfer rate of glucose-coated gold nanoparticles across primary human brain endothelium was at least three times faster than across non-brain endothelia. Movement of these nanoparticles occurred across the apical and basal plasma membranes via the cytosol with relatively little vesicular or paracellular migration; antibiotics that interfere with vesicular transport did not block migration. The transfer rate was also dependent on the surface coating of the nanoparticle and incubation temperature. Using a novel 3-dimensional co-culture system, which includes primary human astrocytes and a brain endothelial cell line hCMEC/D3, we demonstrated that the glucose-coated nanoparticles traverse the endothelium, move through the extracellular matrix and localize in astrocytes. The movement of the nanoparticles through the matrix was >10 µm/hour and they appeared in the nuclei of the astrocytes in considerable numbers. These nanoparticles have the correct properties for efficient and selective carriers of therapeutic agents across the blood-brain barrier.

  15. Pleiotropic effects of coat colour-associated mutations in humans, mice and other mammals.

    Science.gov (United States)

    Reissmann, Monika; Ludwig, Arne

    2013-01-01

    The characterisation of the pleiotropic effects of coat colour-associated mutations in mammals illustrates that sensory organs and nerves are particularly affected by disorders because of the shared origin of melanocytes and neurocytes in the neural crest; e.g. the eye-colour is a valuable indicator of disorders in pigment production and eye dysfunctions. Disorders related to coat colour-associated alleles also occur in the skin (melanoma), reproductive tract and immune system. Additionally, the coat colour phenotype of an individual influences its general behaviour and fitness. Mutations in the same genes often produce similar coat colours and pleiotropic effects in different species (e.g., KIT [reproductive disorders, lethality], EDNRB [megacolon] and LYST [CHS]). Whereas similar disorders and similar-looking coat colour phenotypes sometimes have a different genetic background (e.g., deafness [EDN3/EDNRB, MITF, PAX and SNAI2] and visual diseases [OCA2, RAB38, SLC24A5, SLC45A2, TRPM1 and TYR]). The human predilection for fancy phenotypes that ignore disorders and genetic defects is a major driving force for the increase of pleiotropic effects in domestic species and laboratory subjects since domestication has commenced approximately 18,000 years ago. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Drosophila larvae lacking the bcl-2 gene, buffy, are sensitive to nutrient stress, maintain increased basal target of rapamycin (Tor signaling and exhibit characteristics of altered basal energy metabolism

    Directory of Open Access Journals (Sweden)

    Monserrate Jessica P

    2012-07-01

    Full Text Available Abstract Background B cell lymphoma 2 (Bcl-2 proteins are the central regulators of apoptosis. The two bcl-2 genes in Drosophila modulate the response to stress-induced cell death, but not developmental cell death. Because null mutants are viable, Drosophila provides an optimum model system to investigate alternate functions of Bcl-2 proteins. In this report, we explore the role of one bcl-2 gene in nutrient stress responses. Results We report that starvation of Drosophila larvae lacking the bcl-2 gene, buffy, decreases survival rate by more than twofold relative to wild-type larvae. The buffy null mutant reacted to starvation with the expected responses such as inhibition of target of rapamycin (Tor signaling, autophagy initiation and mobilization of stored lipids. However, the autophagic response to starvation initiated faster in larvae lacking buffy and was inhibited by ectopic buffy. We demonstrate that unusually high basal Tor signaling, indicated by more phosphorylated S6K, was detected in the buffy mutant and that removal of a genomic copy of S6K, but not inactivation of Tor by rapamycin, reverted the precocious autophagy phenotype. Instead, Tor inactivation also required loss of a positive nutrient signal to trigger autophagy and loss of both was sufficient to activate autophagy in the buffy mutant even in the presence of enforced phosphoinositide 3-kinase (PI3K signaling. Prior to starvation, the fed buffy mutant stored less lipid and glycogen, had high lactate levels and maintained a reduced pool of cellular ATP. These observations, together with the inability of buffy mutant larvae to adapt to nutrient restriction, indicate altered energy metabolism in the absence of buffy. Conclusions All animals in their natural habitats are faced with periods of reduced nutrient availability. This study demonstrates that buffy is required for adaptation to both starvation and nutrient restriction. Thus, Buffy is a Bcl-2 protein that plays an

  17. Reduced graphene oxide-coated hydroxyapatite composites stimulate spontaneous osteogenic differentiation of human mesenchymal stem cells

    Science.gov (United States)

    Lee, Jong Ho; Shin, Yong Cheol; Jin, Oh Seong; Kang, Seok Hee; Hwang, Yu-Shik; Park, Jong-Chul; Hong, Suck Won; Han, Dong-Wook

    2015-07-01

    Human mesenchymal stem cells (hMSCs) have great potential as cell sources for bone tissue engineering and regeneration, but the control and induction of their specific differentiation into bone cells remain challenging. Graphene-based nanomaterials are considered attractive candidates for biomedical applications such as scaffolds in tissue engineering, substrates for SC differentiation and components of implantable devices, due to their biocompatible and bioactive properties. Despite the potential biomedical applications of graphene and its derivatives, only limited information is available regarding their osteogenic activity. This study concentrates upon the effects of reduced graphene oxide (rGO)-coated hydroxyapatite (HAp) composites on osteogenic differentiation of hMSCs. The average particle sizes of HAp and rGO were 1270 +/- 476 nm and 438 +/- 180 nm, respectively. When coated on HAp particulates, rGO synergistically enhanced spontaneous osteogenic differentiation of hMSCs, without hampering their proliferation. This result was confirmed by determining alkaline phosphatase activity and mineralization of calcium and phosphate as early and late stage markers of osteogenic differentiation. It is suggested that rGO-coated HAp composites can be effectively utilized as dental and orthopedic bone fillers since these graphene-based particulate materials have potent effects on stimulating the spontaneous differentiation of MSCs and show superior bioactivity and osteoinductive potential.Human mesenchymal stem cells (hMSCs) have great potential as cell sources for bone tissue engineering and regeneration, but the control and induction of their specific differentiation into bone cells remain challenging. Graphene-based nanomaterials are considered attractive candidates for biomedical applications such as scaffolds in tissue engineering, substrates for SC differentiation and components of implantable devices, due to their biocompatible and bioactive properties. Despite

  18. Coating of human decay accelerating factor (hDAF) onto medical devices to improve biocompatibility.

    Science.gov (United States)

    Watkins, N J; Braidley, P; Bray, C J; Savill, C M; White, D J

    1997-12-01

    In passing blood through an artificial circulatory system, the blood is exposed to surfaces that result in activation of the complement system. The consequences of the activation of complement can be extremely serious for the patient ranging from mild discomfort to respiratory distress and even anaphylaxis. An entirely novel approach was to express recombinant GPI anchored human decay accelerating factor (hDAF) using the baculovirus system and then coat the recombinant protein onto the surfaces of these materials to reduce complement activation. Expression of hDAF in Sf9 cells was shown by ELISA, FACS analysis, and Western blot. Functional activity was tested by CH50 assay. For the coating experiments a small scale model of a cardiovascular bypass circuit constructed from COBE tubing was used. hDAF was either coated onto the circuit using adsorption or covalently linked via the photoreactive crosslinker, p-azidobenzoyl hydrazide. After coating, heparinised human blood was pumped around the circuit and samples were collected into EDTA collection tubes at different time points. Complement activation was measured using a Quidel C3a-des-arg EIA. The photolinked circuits gave a reduction in C3a production of 20-50%, compared to 10-20% seen with an absorbed hDAF circuit. Furthermore, the inhibition of complement was seen over the whole time scale of the photolinked circuit, 60-90 min, whilst in the adsorbed circuit inhibition was not seen to a significant degree after 60 min. The time scale of a standard cardiac bypass is 45-90 min, therefore, the photolinked circuit results are encouraging, as significant inhibition of complement activation is seen within this time frame.

  19. UV-activated 7-dehydrocholesterol-coated titanium implants promote differentiation of human umbilical cord mesenchymal stem cells into osteoblasts.

    Science.gov (United States)

    Satué, María; Ramis, Joana M; Monjo, Marta

    2016-01-01

    Vitamin D metabolites are essential for bone regeneration and mineral homeostasis. The vitamin D precursor 7-dehydrocholesterol can be used after UV irradiation to locally produce active vitamin D by osteoblastic cells. Furthermore, UV-irradiated 7-dehydrocholesterol is a biocompatible coating for titanium implants with positive effects on osteoblast differentiation. In this study, we examined the impact of titanium implants surfaces coated with UV-irradiated 7-dehydrocholesterol on the osteogenic differentiation of human umbilical cord mesenchymal stem cells. First, the synthesis of cholecalciferol (D3) was achieved through the incubation of the UV-activated 7-dehydrocholesterol coating for 48 h at 23℃. Further, we investigated in vitro the biocompatibility of this coating in human umbilical cord mesenchymal stem cells and its potential to enhance their differentiation towards the osteogenic lineage. Human umbilical cord mesenchymal stem cells cultured onto UV-irradiated 7-dehydrocholesterol-coated titanium implants surfaces, combined with osteogenic supplements, upregulated the gene expression of several osteogenic markers and showed higher alkaline phosphatase activity and calcein blue staining, suggesting increased mineralization. Thus, our results show that the use of UV irradiation on 7-dehydrocholesterol -treated titanium implants surfaces generates a bioactive coating that promotes the osteogenic differentiation of human umbilical cord mesenchymal stem cells, with regenerative potential for improving osseointegration in titanium-based bone anchored implants. © The Author(s) 2015.

  20. Engineered matrix coatings to modulate the adhesion of CD133+ human hematopoietic progenitor cells.

    Science.gov (United States)

    Franke, Katja; Pompe, Tilo; Bornhäuser, Martin; Werner, Carsten

    2007-02-01

    Interactions of hematopoietic progenitor cells (HPC) with their local microenvironments in the bone marrow are thought to control homing, differentiation, and self-renewal of the cells. To dissect the role of extracellular matrix (ECM) components of the niche microenvironment, a set of well-defined ECM coatings including fibronectin, heparin, heparan sulphate, hyaluronic acid, tropocollagen I, and co-fibrils of collagen I with heparin or hyaluronic acid was prepared and analysed with respect to the attachment of human CD133+ HPC in vitro. The extension of the adhesion areas of individual cells as well as the fraction of adherent cells were assessed by reflection interference contrast microscopy (RICM). Intense cell-matrix interactions were found on surfaces coated with fibronectin, heparin, heparan sulphate, and on the collagen I based co-fibrils. Insignificant adhesion was found for tropocollagen I and hyaluronic acid. The strongest adhesion of HPC was observed on fibronectin with contact areas of about 7 microm(2). Interaction of HPC with coatings consisting of heparin, heparan sulphate, and co-fibrils result in small circular shaped contact zones of 3 microm(2) pointing to another, less efficient, adhesion mechanism. Analysing the specificity of cell-matrix interaction by antibody blocking experiments suggests an integrin(alpha(5)beta(1))-specific adhesion on fibronectin, while adhesion on heparin was shown to be mediated by selectins (CD62L). Taken together, our data provide a basis for the design of advanced culture carriers supporting site-specific proliferation or differentiation of HPC.

  1. Viability of pHEMA Hydrogels as Coating in Human Synovial Joint Prosthesis

    Directory of Open Access Journals (Sweden)

    V.P. Bavaresco

    2002-10-01

    Full Text Available In artificial joints, the bone part is usually substituted by a metallic component with high corrosion and strength resistance while the articular cartilage is replaced by a polymer. Use of thin layer of a compliant material acting as a bearing surface in human replacement joints has recently generated considerable interest. This work analyses the coating of a solid porous substrate of Ultra High Molecular Weight Polyethylene (UHMWPE with a poly (2-hydroxyethyl methacrylate (pHEMA and two sIPN-type blends: pHEMA-cellulose acetate butyrate (CAB and pHEMA-poly (ethyl methacrylate (PEM using 5.0% (w/w of the crosslinking agent and 11.0% (w/w of the linear reinforcing polymer. The wear resistance of the coating materials was evaluated in a TRI PIN ON DISK type equipment and the damage extension was characterized by Scanning Electron Microscopy (SEM. Preliminary qualitative tests were performed with the goal to identifying the hydrogels show the minimal required properties concerning wear strength. The pHEMA coating was completely destroyed during the first wear cycles, characterizing its low shear strength. By the other hand, after the complete experiment, both pHEMA-CAB and pHEMA-PEM blends showed a slightly improvement of abrasive and adhesive wear. This result indicates that the studied blends are promising materials to be used as compliant surfaces in joint prosthesis.

  2. Platelet activation during preparation of platelet concentrates: a comparison of the platelet-rich plasma and the buffy coat methods

    NARCIS (Netherlands)

    Fijnheer, R.; Pietersz, R. N.; de Korte, D.; Gouwerok, C. W.; Dekker, W. J.; Reesink, H. W.; Roos, D.

    1990-01-01

    The activation of platelets during the preparation of platelet concentrates (PCs) by two methods was compared. To eliminate interdonor differences, 2 units of whole blood were pooled and subsequently divided into two batches. From one batch, the platelets were harvested as pelleted platelets from

  3. Transfusion of pooled buffy coat platelet components prepared with photochemical pathogen inactivation treatment: the euroSPRITE trial

    NARCIS (Netherlands)

    D.J. van Rhenen (Dirk Jan); S. Marblie (Stephane); M. Laforet (Michel); K. Davis (Kathryn); M. Conlan (Maureen); B. Lioure (Bruno); H. Gulliksson (Hans); J.P. Cazenave; P. Metzel (Peyton); D. Pamphilon (Derwood); L. Corash (Laurence); J. Flament (Jocelyne); P. Ljungman (Per); H. Kluter; H. Vermeij (Hans); V. Mayaudon (Veronique); L. Lin (Lily); M.C. Kappers-Klunne (Mies); D. Buchholz (Don); G.E. de Greef (Georgine)

    2003-01-01

    textabstractA nucleic acid-targeted photochemical treatment (PCT) using amotosalen HCl (S-59) and ultraviolet A (UVA) light was developed to inactivate viruses, bacteria, protozoa, and leukocytes in platelet components. We conducted a controlled, randomized, double-blinded trial in thrombocytopenic

  4. Preparation and radiolabeling of human serum albumin (HSA)-coated magnetite nanoparticles for magnetically targeted therapy

    International Nuclear Information System (INIS)

    Zhang Chunfu; Cao Jinquan; Yin Duanzhi; Wang Yongxian; Feng Yanlin; Tan Jiajue

    2004-01-01

    In this paper, we describe the preparation of human serum albumin-coated magnetic particles of about 200 nm in diameter with narrow size distribution radiolabeled with 188 Re for the purpose of magnetically targeted therapy. The optimum radiolabeling conditions are: SnCl 2 ·2H 2 O 8 mg/ml, citric acid 20 mg/ml, vitamin C 8 mg/ml, labeling volume 500 μl and a reaction time of 3 h. The stability of the radiolabeled particles is suitable for in vivo study

  5. Preparation and radiolabeling of human serum albumin (HSA)-coated magnetite nanoparticles for magnetically targeted therapy

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Chunfu E-mail: zchunfu@yahoo.com.cn; Cao Jinquan; Yin Duanzhi; Wang Yongxian; Feng Yanlin; Tan Jiajue

    2004-12-01

    In this paper, we describe the preparation of human serum albumin-coated magnetic particles of about 200 nm in diameter with narrow size distribution radiolabeled with {sup 188}Re for the purpose of magnetically targeted therapy. The optimum radiolabeling conditions are: SnCl{sub 2}{center_dot}2H{sub 2}O 8 mg/ml, citric acid 20 mg/ml, vitamin C 8 mg/ml, labeling volume 500 {mu}l and a reaction time of 3 h. The stability of the radiolabeled particles is suitable for in vivo study.

  6. Natural History of Bone Response to Hydroxyapatite-Coated Hip Prostheses Implanted in Humans

    OpenAIRE

    Frayssinet, P.; Hardy, D.; Hanker, J. S.; Giammara, B. L.

    1995-01-01

    A series of 15 autopsied femurs containing hydroxyapatite- coated (HA-coated) prostheses was analysed histologically. Their implantation time ranged from 5 days up to 3 years. The coating thickness of some prostheses and the percentage of the coating in contact with bone at different levels were evaluated using an image analysis device. After the newly formed bone tissue had became mature, several bone morphotypes were identified at the coating contact. From the proximal to the distal part of...

  7. Efficient internalization of silica-coated iron oxide nanoparticles of different sizes by primary human macrophages and dendritic cells

    International Nuclear Information System (INIS)

    Kunzmann, Andrea; Andersson, Britta; Vogt, Carmen; Feliu, Neus; Ye Fei; Gabrielsson, Susanne; Toprak, Muhammet S.; Buerki-Thurnherr, Tina; Laurent, Sophie; Vahter, Marie; Krug, Harald; Muhammed, Mamoun; Scheynius, Annika; Fadeel, Bengt

    2011-01-01

    Engineered nanoparticles are being considered for a wide range of biomedical applications, from magnetic resonance imaging to 'smart' drug delivery systems. The development of novel nanomaterials for biomedical applications must be accompanied by careful scrutiny of their biocompatibility. In this regard, particular attention should be paid to the possible interactions between nanoparticles and cells of the immune system, our primary defense system against foreign invasion. On the other hand, labeling of immune cells serves as an ideal tool for visualization, diagnosis or treatment of inflammatory processes, which requires the efficient internalization of the nanoparticles into the cells of interest. Here, we compare novel monodispersed silica-coated iron oxide nanoparticles with commercially available dextran-coated iron oxide nanoparticles. The silica-coated iron oxide nanoparticles displayed excellent magnetic properties. Furthermore, they were non-toxic to primary human monocyte-derived macrophages at all doses tested whereas dose-dependent toxicity of the smaller silica-coated nanoparticles (30 nm and 50 nm) was observed for primary monocyte-derived dendritic cells, but not for the similarly small dextran-coated iron oxide nanoparticles. No macrophage or dendritic cell secretion of pro-inflammatory cytokines was observed upon administration of nanoparticles. The silica-coated iron oxide nanoparticles were taken up to a significantly higher degree when compared to the dextran-coated nanoparticles, irrespective of size. Cellular internalization of the silica-coated nanoparticles was through an active, actin cytoskeleton-dependent process. We conclude that these novel silica-coated iron oxide nanoparticles are promising materials for medical imaging, cell tracking and other biomedical applications.

  8. TiO2-enriched polymeric powder coatings support human mesenchymal cell spreading and osteogenic differentiation

    International Nuclear Information System (INIS)

    Mozumder, Mohammad Sayem; Zhu, Jesse; Perinpanayagam, Hiran

    2011-01-01

    Novel polymeric powder coatings (PPC) were prepared by ultrafine powder coating technology and shown to support human mesenchymal cell attachment and growth. PPC surfaces enriched with nano-TiO 2 (nTiO 2 ) showed enhanced cellular responses, and were compared to commercially pure titanium (cpTi). After cell attachment and growth, osteogenic differentiation and bone matrix formation ensures osseointegration for implantable biomaterials. Therefore, the objective of this study was to determine if mesenchymal cells grown on PPC could undergo osteogenic differentiation by inducing Runx2 and bone matrix proteins, and then initiate mineralization. Atomic force microscopy revealed intricate three-dimensional micro-topographies, and the measures of nano-roughness and porosity were similar for all PPC surfaces. Scanning electron microscopy showed that the cells attached and spread out over all of the surfaces. After 1 week in osteogenic media, RT-PCR analysis showed the induction of Runx2, the up-regulation of type I collagen, and the initial detection of alkaline phosphatase and bone sialoprotein. After 4 weeks, Alizarin Red staining showed mineral deposition. However, cell spreading and osteogenic differentiation were significantly (P 2 additives may enhance their performance.

  9. Mechanism of Dimercaptosuccinic Acid Coated Superparamagnetic Iron Oxide Nanoparticles with Human Serum Albumin.

    Science.gov (United States)

    Zhao, Lining; Song, Wei; Wang, Jing; Yan, Yunxing; Chen, Jiangwei; Liu, Rutao

    2015-12-01

    To research the mechanism of dimercaptosuccinic acid coated-superparamagnetic iron oxide nanoparticles (SPION) with human serum albumin (HSA), the methods of spectroscopy, molecular modeling calculation, and calorimetry were used in this paper. The inner filter effect of the fluorescence intensity was corrected to obtain the accurate results. Ultraviolet-visible absorption and circular dichroism spectra reflect that SPION changed the secondary structure with a loss of α-helix and loosened the protein skeleton of HSA; the activity of the protein was also affected by the increasing exposure of SPION. Fluorescence lifetime measurement indicates that the quenching mechanism type of this system was static quenching. The isothermal titration calorimetry measurement and molecular docking calculations prove that the predominant force of this system was the combination of Van der Waals' force and hydrogen bonds. © 2015 Wiley Periodicals, Inc.

  10. Poly(norepinephrine)-coated open tubular column for the separation of proteins and recombination human erythropoietin by capillary electrochromatography.

    Science.gov (United States)

    Xiao, Xue; Zhang, Yamin; Wu, Jia; Jia, Li

    2017-12-01

    Recombinant human erythropoietin is an important therapeutic protein with high economic interest due to the benefits provided by its clinical use for the treatment of anemias associated with chronic renal failure and chemotherapy. In this work, a poly(norepinephrine)-coated open tubular column was successfully prepared based on the self-polymerization of norepinephrine under mild alkaline condition, the favorable film forming and easy adhesive properties of poly(norepinephrine). The poly(norepinephrine) coating was characterized by scanning electron microscopy and measurement of the electro-osmotic flow. The thickness of the coating was about 431 nm. The electrochromatographic performance of the poly(norepinephrine)-coated open tubular column was evaluated by separation of proteins. Some basic and acidic proteins including two variants of bovine serum albumin and two variants of β-lactoglobulin achieved separation in the poly(norepinephrine)-coated open tubular column. More importantly, the column demonstrated separation ability for the glycoforms of recombinant human erythropoietin. In addition, the column demonstrated good repeatability with the run-to-run, day-to-day, and column-to-column relative standard deviations of migration times of proteins less than 3.40%. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. The impact of extracellular matrix coatings on the performance of human renal cells applied in bioartificial kidneys.

    Science.gov (United States)

    Zhang, Huishi; Tasnim, Farah; Ying, Jackie Y; Zink, Daniele

    2009-05-01

    Extracellular matrix (ECM) coatings have been used to improve cell performance in bioartificial kidneys (BAKs). However, their effects on primary human renal proximal tubule cells (HPTCs), which is the most important cell type with regard to clinical applications, have not been tested systematically. Also, the effects of ECM coatings on cell performance during extended time periods have not been addressed. Studying such effects is important for the development of long-term applications. Herein we analyzed for the first time systematically the effects of ECM coatings on proliferation and differentiation of human renal cells and we addressed, in particular, formation and long-term maintenance of differentiated epithelia. Our study focused on HPTCs. ECM coatings were tested alone or in combination with the growth factor bone morphogenetic protein-7 and other additives. The best results were obtained with ECMs consisting of the basal lamina components, laminin or collagen IV, and differentiated epithelia could be maintained up to three weeks on these ECMs. These results provide for the first time clear evidence which kinds of ECM coatings are most appropriate for BAKs. The results also showed that alpha-SMA-expressing myofibroblasts played a key role in the final disruption of differentiated epithelia. This suggests that epithelial-to-mesenchymal transition-related processes might be the major obstacle in long-term applications and such processes should be carefully addressed in future BAK-related research.

  12. TiO2 coating promotes human mesenchymal stem cell proliferation without the loss of their capacity for chondrogenic differentiation

    International Nuclear Information System (INIS)

    Kaitainen, Salla; Lappalainen, Reijo; Mähönen, Anssi J; J Lammi, Mikko; Qu, Chengjuan; Kröger, Heikki

    2013-01-01

    Human mesenchymal stem cells (hMSCs) are used in applications, which may require a large amount of cells; therefore, efficient expansion of the cells is desired. We studied whether TiO 2 coating on plastic cell culture dishes could promote proliferation of hMSCs without adverse effects in chondrogenic differentiation. TiO 2 -films were deposited on polystyrene dishes and glass coverslips using an ultrashort pulsed laser deposition technique. Human MSCs from three donors were expanded on them until 95% confluence, and the cells were evaluated by morphology, immunocytochemistry and quantitative RT-PCR (qRT-PCR). The chondrogenic differentiation in pellets was performed after cultivation on TiO 2 -coated dishes. Chondrogenesis was evaluated by histological staining of proteoglycans and type II collagen, and qRT-PCR. Human MSC-associated markers STRO-1, CD44, CD90 and CD146 did not change after expansion on TiO 2 -coated coverslips. However, the cell number after a 48h-culture period was significantly higher on TiO 2 -coated culture dishes. Importantly, TiO 2 coating caused no significant differences in the proteoglycan and type II collagen staining of the pellets, or the expression of chondrocyte-specific genes in the chondrogenesis assay. Thus, the proliferation of hMSCs could be significantly increased when cultured on TiO 2 -coated dishes without weakening their chondrogenic differentiation capacity. The transparency of TiO 2 -films allows easy monitoring of the cell growth and morphology under a phase-contrast microscope. (paper)

  13. RGO-coated elastic fibres as wearable strain sensors for full-scale detection of human motions

    Science.gov (United States)

    Mi, Qing; Wang, Qi; Zang, Siyao; Mao, Guoming; Zhang, Jinnan; Ren, Xiaomin

    2018-01-01

    In this study, we chose highly-elastic fabric fibres as the functional carrier and then simply coated the fibres with reduced graphene oxide (rGO) using plasma treatment, dip coating and hydrothermal reduction steps, finally making a wearable strain sensor. As a result, the full-scale detection of human motions, ranging from bending joints to the pulse beat, has been achieved by these sensors. Moreover, high sensitivity, good stability and excellent repeatability were realized. The good sensing performances and economical fabrication process of this wearable strain sensor have strengthened our confidence in practical applications in smart clothing, smart fabrics, healthcare, and entertainment fields.

  14. Transferrin coated nanoparticles: study of the bionano interface in human plasma.

    Directory of Open Access Journals (Sweden)

    Andrzej S Pitek

    Full Text Available It is now well established that the surface of nanoparticles (NPs in a biological environment is immediately modified by the adsorption of biomolecules with the formation of a protein corona and it is also accepted that the protein corona, rather than the original nanoparticle surface, defines a new biological identity. Consequently, a methodology to effectively study the interaction between nanomaterials and the biological corona encountered within an organism is a key objective in nanoscience for understanding the impact of the nanoparticle-protein interactions on the biological response in vitro and in vivo. Here, we outline an integrated methodology to address the different aspects governing the formation and the function of the protein corona of polystyrene nanoparticles coated with Transferrin by different strategies. Protein-NP complexes are studied both in situ (in human plasma, full corona FC and after washing (hard corona, HC in terms of structural properties, composition and second-order interactions with protein microarrays. Human protein microarrays are used to effectively study NP-corona/proteins interactions addressing the growing demand to advance investigations of the extrinsic function of corona complexes. Our data highlight the importance of this methodology as an analysis to be used in advance of the application of engineered NPs in biological environments.

  15. Effects of PVA-coated nanoparticles on human T helper cell activity.

    Science.gov (United States)

    Strehl, Cindy; Schellmann, Saskia; Maurizi, Lionel; Hofmann-Amtenbrink, Margarethe; Häupl, Thomas; Hofmann, Heinrich; Buttgereit, Frank; Gaber, Timo

    2016-03-14

    Superparamagnetic iron oxide nanoparticles (SPION) are used as high-sensitive enhancer for magnetic resonance imaging, where they represent a promising tool for early diagnosis of destructive diseases such as rheumatoid arthritis (RA). Since we could demonstrate that professional phagocytes are activated by amino-polyvinyl-alcohol-coated-SPION (a-PVA-SPION), the study here focuses on the influence of a-PVA-SPION on human T cells activity. Therefore, primary human CD4+ T cells from RA patients and healthy subjects were treated with varying doses of a-PVA-SPION for 20h or 72h. T cells were then analyzed for apoptosis, cellular energy, expression of the activation marker CD25 and cell proliferation. Although, we observed that T cells from RA patients are more susceptible to low-dose a-PVA-SPION-induced apoptosis than T cells from healthy subjects, in both groups a-PVA-SPION do not activate CD4+ T cells per se and do not influence mitogen-mediated T cells activation with regard to CD25 expression and cell proliferation. Nevertheless, our results demonstrate that CD4+ T cells from RA patients and healthy subjects differ in their response to mitogen stimulation and oxygen availability. We conclude from our data, that a-PVA-SPION do neither activate nor significantly influence mitogen-stimulated CD4+ T cells activation and have negligible influence on T cells apoptosis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. Modulation of human dermal microvascular endothelial cell and human gingival fibroblast behavior by micropatterned silica coating surfaces for zirconia dental implant applications

    International Nuclear Information System (INIS)

    Laranjeira, Marta S; Carvalho, Ângela; Ferraz, Maria Pia; Monteiro, Fernando Jorge; Pelaez-Vargas, Alejandro; Hansford, Derek; Coimbra, Susana; Costa, Elísio; Santos-Silva, Alice; Fernandes, Maria Helena

    2014-01-01

    Dental ceramic implants have shown superior esthetic behavior and the absence of induced allergic disorders when compared to titanium implants. Zirconia may become a potential candidate to be used as an alternative to titanium dental implants if surface modifications are introduced. In this work, bioactive micropatterned silica coatings were produced on zirconia substrates, using a combined methodology of sol–gel processing and soft lithography. The aim of the work was to compare the in vitro behavior of human gingival fibroblasts (HGFs) and human dermal microvascular endothelial cells (HDMECs) on three types of silica-coated zirconia surfaces: flat and micropatterned (with pillars and with parallel grooves). Our results showed that cells had a higher metabolic activity (HGF, HDMEC) and increased gene expression levels of fibroblast-specific protein-1 (FSP-1) and collagen type I (COL I) on surfaces with pillars. Nevertheless, parallel grooved surfaces were able to guide cell growth. Even capillary tube-like networks of HDMEC were oriented according to the surface geometry. Zirconia and silica with different topographies have shown to be blood compatible and silica coating reduced bacteria adhesion. All together, the results indicated that microstructured bioactive coating seems to be an efficient strategy to improve soft tissue integration on zirconia implants, protecting implants from peri-implant inflammation and improving long-term implant stabilization. This new approach of micropatterned silica coating on zirconia substrates can generate promising novel dental implants, with surfaces that provide physical cues to guide cells and enhance their behavior. (paper)

  17. Xeno-Free Strategies for Safe Human Mesenchymal Stem/Stromal Cell Expansion: Supplements and Coatings

    Directory of Open Access Journals (Sweden)

    M. Cimino

    2017-01-01

    Full Text Available Human mesenchymal stem/stromal cells (hMSCs have generated great interest in regenerative medicine mainly due to their multidifferentiation potential and immunomodulatory role. Although hMSC can be obtained from different tissues, the number of available cells is always low for clinical applications, thus requiring in vitro expansion. Most of the current protocols for hMSC expansion make use of fetal bovine serum (FBS as a nutrient-rich supplement. However, regulatory guidelines encourage novel xeno-free alternatives to define safer and standardized protocols for hMSC expansion that preserve their intrinsic therapeutic potential. Since hMSCs are adherent cells, the attachment surface and cell-adhesive components also play a crucial role on their successful expansion. This review focuses on the advantages/disadvantages of FBS-free media and surfaces/coatings that avoid the use of animal serum, overcoming ethical issues and improving the expansion of hMSC for clinical applications in a safe and reproducible way.

  18. Effect of HSA coated iron oxide labeling on human umbilical cord derived mesenchymal stem cells

    Science.gov (United States)

    Sanganeria, Purva; Chandra, Sudeshna; Bahadur, Dhirendra; Khanna, Aparna

    2015-03-01

    Human umbilical cord derived mesenchymal stem cells (hUC-MSCs) are known for self-renewal and differentiation into cells of various lineages like bone, cartilage and fat. They have been used in biomedical applications to treat degenerative disorders. However, to exploit the therapeutic potential of stem cells, there is a requirement of sensitive non-invasive imaging techniques which will offer the ability to track transplanted cells, bio-distribution, proliferation and differentiation. In this study, we have analyzed the efficacy of human serum albumin coated iron oxide nanoparticles (HSA-IONPs) on the differentiation of hUC-MSCs. The colloidal stability of the HSA-IONPs was tested over a long period of time (≥20 months) and the optimized concentration of HSA-IONPs for labeling the stem cells was 60 μg ml-1. Detailed in vitro assays have been performed to ascertain the effect of the nanoparticles (NPs) on stem cells. Lactate dehydrogenase (LDH) assay showed minimum release of LDH depicting the least disruptions in cellular membrane. At the same time, mitochondrial impairment of the cells was also not observed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Flow cytometry analysis revealed lesser generation of reactive oxygen species in HSA-IONPs labeled hUC-MSCs in comparison to bare and commercial IONPs. Transmission electron microscopy showed endocytic engulfment of the NPs by the hUC-MSCs. During the process, the gross morphologies of the actin cytoskeleton were found to be intact as shown by immunofluorescence microscopy. Also, the engulfment of the HSA-IONPs did not show any detrimental effect on the differentiation potential of the stem cells into adipocytes, osteocytes and chondrocytes, thereby confirming that the inherent properties of stem cells were maintained.

  19. Advantages of bioconjugated silica-coated nanoparticles as an innovative diagnosis for human toxoplasmosis.

    Science.gov (United States)

    Aly, Ibrahim; Taher, Eman E; El Nain, Gehan; El Sayed, Hoda; Mohammed, Faten A; Hamad, Rabab S; Bayoumy, Elsayed M

    2018-01-01

    Nanotechnology is a promising arena for generating new applications in Medicine. To successfully functionalised nanoparticles for a given biomedical application, a wide range of chemical, physical and biological factors have to be taken into account. Silica-coated nanoparticles, (SiO2NP) exhibit substantial diagnostic activity owing to their large surface to volume ratios and crystallographic surface structure. This work aimed to evaluate the advantage of bioconjugation of SiO2NP with PAb against Toxoplasma lyzate antigen (TLA) as an innovative diagnostic method for human toxoplasmosis. This cross-sectional study included 120 individuals, divided into Group I: 70 patients suspected for Toxoplasma gondii based on the presence of clinical manifestation. Group II: 30 patients harboring other parasites than T. gondii Group III: 20 apparently healthy individuals free from toxoplasmosis and other parasitic infections served as negative control. Detection of circulating Toxoplasma antigen was performed by Sandwich ELISA and Nano-sandwich ELISA on sera and pooled urine of human samples. Using Sandwich ELISA, 10 out of 70 suspected Toxoplasma-infected human serum samples showed false negative and 8 out of 30 of other parasites groups were false positive giving 85.7% sensitivity and 84.0% specificity, while the sensitivity and specificity were 78.6% and 70% respectively in urine samples. Using Nano-Sandwich ELISA, 7 out of 70 suspected Toxoplasma-infected human samples showed false negative results and the sensitivity of the assay was 90.0%, while 4 out of 30 of other parasites groups were false positive giving 92.0% specificity, while the sensitivity and specificity were 82.6% and 80% respectively in urine samples. In conclusion, our data demonstrated that loading SiO2 nanoparticles with pAb increased the sensitivity and specificity of Nano-sandwich ELISA for detection of T.gondii antigens in serum and urine samples, thus active (early) and light infections could be easily

  20. Biological Response of Human Bone Marrow-Derived Mesenchymal Stem Cells to Commercial Tantalum Coatings with Microscale and Nanoscale Surface Topographies

    Science.gov (United States)

    Skoog, Shelby A.; Kumar, Girish; Goering, Peter L.; Williams, Brian; Stiglich, Jack; Narayan, Roger J.

    2016-06-01

    Tantalum is a promising orthopaedic implant coating material due to its robust mechanical properties, corrosion resistance, and excellent biocompatibility. Previous studies have demonstrated improved biocompatibility and tissue integration of surface-treated tantalum coatings compared to untreated tantalum. Surface modification of tantalum coatings with biologically inspired microscale and nanoscale features may be used to evoke optimal tissue responses. The goal of this study was to evaluate commercial tantalum coatings with nanoscale, sub-microscale, and microscale surface topographies for orthopaedic and dental applications using human bone marrow-derived mesenchymal stem cells (hBMSCs). Tantalum coatings with different microscale and nanoscale surface topographies were fabricated using a diffusion process or chemical vapor deposition. Biological evaluation of the tantalum coatings using hBMSCs showed that tantalum coatings promote cellular adhesion and growth. Furthermore, hBMSC adhesion to the tantalum coatings was dependent on surface feature characteristics, with enhanced cell adhesion on sub-micrometer- and micrometer-sized surface topographies compared to hybrid nano-/microstructures. Nanostructured and microstructured tantalum coatings should be further evaluated to optimize the surface coating features to promote osteogenesis and enhance osseointegration of tantalum-based orthopaedic implants.

  1. Phospholipase D is involved in the formation of Golgi associated clathrin coated vesicles in human parotid duct cells.

    Directory of Open Access Journals (Sweden)

    Lorena Brito de Souza

    Full Text Available Phospholipase D (PLD has been implicated in many cellular functions, such as vesicle trafficking, exocytosis, differentiation, and proliferation. The aim of this study was to characterize the role of PLD in HSY cells, a human cell line originating from the intercalated duct of the parotid gland. As the function and intracellular localization of PLD varies according to cell type, initially, the intracellular localization of PLD1 and PLD2 was determined. By immunofluorescence, PLD1 and PLD2 both showed a punctate cytoplasmic distribution with extensive co-localization with TGN-46. PLD1 was also found in the nucleus, while PLD2 was associated with the plasma membrane. Treatment of cells with the primary alcohol 1-butanol inhibits the hydrolysis of phosphatidylcoline by PLD thereby suppressing phosphatidic acid (PA production. In untreated HSY cells, there was only a slight co-localization of PLD with the clathrin coated vesicles. When HSY cells were incubated with 1-butanol the total number of clathrin coated vesicles increased, especially in the juxtanuclear region and the co-localization of PLD with the clathrin coated vesicles was augmented. Transmission electron microscopy confirmed that the number of Golgi-associated coated vesicles was greater. Treatment with 1-butanol also affected the Golgi apparatus, increasing the volume of the Golgi saccules. The decrease in PA levels after treatment with 1-butanol likewise resulted in an accumulation of enlarged lysosomes in the perinuclear region. Therefore, in HSY cells PLD appears to be involved in the formation of Golgi associated clathrin coated vesicles as well as in the structural maintenance of the Golgi apparatus.

  2. Mechanisms of complement activation by dextran-coated superparamagnetic iron oxide (SPIO) nanoworms in mouse versus human serum

    DEFF Research Database (Denmark)

    Banda, Nirmal K; Mehta, Gaurav; Chao, Ying

    2014-01-01

    BACKGROUND: The complement system is a key component of innate immunity implicated in the neutralization and clearance of invading pathogens. Dextran coated superparamagnetic iron oxide (SPIO) nanoparticle is a promising magnetic resonance imaging (MRI) contrast agent. However, dextran SPIO has...... the mechanisms of human complement activation. Mouse data were analyzed by non-paired t-test, human data were analyzed by ANOVA followed by multiple comparisons with Student-Newman-Keuls test. RESULTS: In mouse sera, SPIO NW triggered the complement activation via the LP, whereas the AP contributes via...... the CP, but that did not affect the total level of C3 deposition on the particles. CONCLUSIONS: There were important differences and similarities in the complement activation by SPIO NW in mouse versus human sera. Understanding the mechanisms of immune recognition of nanoparticles in mouse and human...

  3. Inflammatory responses of a human keratinocyte cell line to 10 nm citrate- and PEG-coated silver nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Bastos, V. [University of Aveiro, CESAM & Laboratory of Biotechnology and Cytomics (Portugal); Brown, D.; Johnston, H. [Heriot-Watt University, School of Life Sciences (United Kingdom); Daniel-da-Silva, A. L.; Duarte, I. F. [University of Aveiro, Department of Chemistry, CICECO – Aveiro Institute of Materials (Portugal); Santos, C., E-mail: csantos@fc.up.pt; Oliveira, H. [University of Aveiro, CESAM & Laboratory of Biotechnology and Cytomics (Portugal)

    2016-07-15

    Silver nanoparticles (AgNPs) are among the most commonly used engineered NPs and various commercially available products are designed to come in direct contact with the skin (wound dressings, textiles, creams, among others). Currently, there is limited understanding of the influence of coatings on the toxicity of AgNPs and in particular their ability to impact on AgNP’s mediated inflammatory responses. As AgNPs are often stabilized by different coatings, including citrate and polyethyleneglycol (PEG), in this study we investigate the influence of citrate (Cit10) or PEG (PEG10) coatings to 10 nm AgNP on skin, using human HaCaT keratinocytes. AgNPs cytotoxicity and inflammatory response (nuclear factor (NF)-κB induction and cytokine production) of HaCaT were assessed after in vitro exposure to 10 and 40 µg/mL after 4, 24, and 48 h. Results showed that although both types of coated AgNPs decreased cell proliferation and viability, Cit10 AgNPs were more toxic. NF-κB inhibition was observed for the highest concentration (40 µg/mL) of PEG10 AgNPs, and the putative link to early apoptotic pathways observed in these cells is discussed. No production of IL-1β, IL-6, IL-10, and TNFα was stimulated by AgNPs. Furthermore, Cit10 and PEG10 AgNPs decreased the release of MCP-1 by HaCaT cells after 48 h of exposure. As cytokines are vital for the immunologic regulation in the human body, and it is demonstrated that they may interfere with NPs, more research is needed to understand how different AgNPs affect the immune system.

  4. Organic composite-mediated surface coating of human acellular bone matrix with strontium.

    Science.gov (United States)

    Huang, Yi-Zhou; Wang, Jing-Jing; Huang, Yong-Can; Wu, Cheng-Guang; Zhang, Yi; Zhang, Chao-Liang; Bai, Lin; Xie, Hui-Qi; Li, Zhao-Yang; Deng, Li

    2018-03-01

    Acellular bone matrix (ACBM) provides an osteoconductive scaffold for bone repair, but its osteoinductivity is poor. Strontium (Sr) improves the osteoinductivity of bone implants. In this study, we developed an organic composite-mediated strontium coating strategy for ACBM scaffolds by using the ion chelating ability of carboxymethyl cellulose (CMC) and the surface adhesion ability of dopamine (DOPA). The organic coating composite, termed the CMC-DOPA-Sr composite, was synthesized under a mild condition, and its chemical structure and strontium ion chelating ability were then determined. After surface decoration, the physicochemical properties of the strontium-coated ACBM (ACBM-Sr) scaffolds were characterized, and their biocompatibility and osteoinductivity were determined in vitro and in vivo. The results showed that the CMC-DOPA-Sr composite facilitated strontium coating on the surface of ACBM scaffolds. The ACBM-Sr scaffolds possessed a sustained strontium ion release profile, exhibited good cytocompatibility, and enhanced the osteogenic differentiation of mesenchymal stem cells in vitro. Furthermore, the ACBM-Sr scaffolds showed good histocompatibility after subcutaneous implantation in nude mice. Taken together, this study provided a simple and mild strategy to realize strontium coating for ACBM scaffolds, which resulted in good biocompatibility and improved osteoinductivity. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Buffy the Vampire Slayer and Xena: Warrior Princess: reception of the texts by a sample of lesbian fans and web site users.

    Science.gov (United States)

    Collier, Noelle R; Lumadue, Christine A; Wooten, H Ray

    2009-01-01

    This qualitative study of television reception examined the ways in which a sample of lesbian fans of Buffy the Vampire Slayer and Xena: Warrior Princess incorporated their experiences as viewers, fans, and Internet users with relation to their sexual identity as lesbians. Specifically, this study examined the ways in which participants used these television programs to inform their sexual identity development. Results indicated that participants used television and the Internet to normalize and affirm lesbian experience, to decrease negative feelings regarding their lesbian identities, and to decrease social isolation.

  6. Tantalum coating on TiO{sub 2} nanotubes induces superior rate of matrix mineralization and osteofunctionality in human osteoblasts

    Energy Technology Data Exchange (ETDEWEB)

    Frandsen, Christine J.; Brammer, Karla S. [Materials Science and Engineering, University of California at San Diego, La Jolla, CA 92093 (United States); Noh, Kunbae [Corporate Research Institute, Cheil Industries, Inc., Gocheon-Dong, Uiwang-Si, Gyeonggi-Do, 437-711 (Korea, Republic of); Johnston, Gary [Materials Science and Engineering, University of California at San Diego, La Jolla, CA 92093 (United States); Jin, Sungho, E-mail: jin@ucsd.edu [Materials Science and Engineering, University of California at San Diego, La Jolla, CA 92093 (United States); Mechanical and Aerospace Engineering, University of California at San Diego, La Jolla, CA 92093 (United States)

    2014-04-01

    Nanostructured surface geometries have been the focus of a multitude of recent biomaterial research, and exciting findings have been published. However, only a few publications have directly compared nanostructures of various surface chemistries. The work herein directly compares the response of human osteoblast cells to surfaces of identical nanotube geometries with two well-known orthopedic biomaterials: titanium oxide (TiO{sub 2}) and tantalum (Ta). The results reveal that the Ta surface chemistry on the nanotube architecture enhances alkaline phosphatase activity, and promotes a ∼ 30% faster rate of matrix mineralization and bone-nodule formation when compared to results on bare TiO{sub 2} nanotubes. This study implies that unique combinations of surface chemistry and nanostructure may influence cell behavior due to distinctive physico-chemical properties. These findings are of paramount importance to the orthopedics field for understanding cell behavior in response to subtle alterations in nanostructure and surface chemistry, and will enable further insight into the complex manipulation of biomaterial surfaces. With increased focus in the field of orthopedic materials research on nanostructured surfaces, this study emphasizes the need for careful and systematic review of variations in surface chemistry in concurrence with nanotopographical changes. - Highlights: • A TiO{sub 2} nanotube surface structure was coated with tantalum. • Osteoblast cell response was compared between the tantalum coated and as-formed TiO{sub 2} nanotube surface. • We observed superior rates of bone matrix mineralization and osteoblast maturation on the tantalum coated nanotube surface.

  7. Tantalum coating on TiO2 nanotubes induces superior rate of matrix mineralization and osteofunctionality in human osteoblasts

    International Nuclear Information System (INIS)

    Frandsen, Christine J.; Brammer, Karla S.; Noh, Kunbae; Johnston, Gary; Jin, Sungho

    2014-01-01

    Nanostructured surface geometries have been the focus of a multitude of recent biomaterial research, and exciting findings have been published. However, only a few publications have directly compared nanostructures of various surface chemistries. The work herein directly compares the response of human osteoblast cells to surfaces of identical nanotube geometries with two well-known orthopedic biomaterials: titanium oxide (TiO 2 ) and tantalum (Ta). The results reveal that the Ta surface chemistry on the nanotube architecture enhances alkaline phosphatase activity, and promotes a ∼ 30% faster rate of matrix mineralization and bone-nodule formation when compared to results on bare TiO 2 nanotubes. This study implies that unique combinations of surface chemistry and nanostructure may influence cell behavior due to distinctive physico-chemical properties. These findings are of paramount importance to the orthopedics field for understanding cell behavior in response to subtle alterations in nanostructure and surface chemistry, and will enable further insight into the complex manipulation of biomaterial surfaces. With increased focus in the field of orthopedic materials research on nanostructured surfaces, this study emphasizes the need for careful and systematic review of variations in surface chemistry in concurrence with nanotopographical changes. - Highlights: • A TiO 2 nanotube surface structure was coated with tantalum. • Osteoblast cell response was compared between the tantalum coated and as-formed TiO 2 nanotube surface. • We observed superior rates of bone matrix mineralization and osteoblast maturation on the tantalum coated nanotube surface

  8. Osteogenesis of human adipose-derived stem cells on poly(dopamine)-coated electrospun poly(lactic acid) fiber mats

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Chi-Chang, E-mail: chichang31@thu.edu.tw; Fu, Shu-Juan

    2016-01-01

    Electrospinning is a versatile technique to generate large quantities of micro- or nano-fibers from a wide variety of shapes and sizes of polymer. The aim of this study is to develop functionalized electrospun nano-fibers and use a mussel-inspired surface coating to regulate adhesion, proliferation and differentiation of human adipose-derived stem cells (hADSCs). We prepared poly(lactic acid) (PLA) fibers coated with polydopamine (PDA). The morphology, chemical composition, and surface properties of PDA/PLA were characterized by SEM and XPS. PDA/PLA modulated hADSCs' responses in several ways. Firstly, adhesion and proliferation of hADSCs cultured on PDA/PLA were significantly enhanced relative to those on PLA. Increased focal adhesion kinase (FAK) and collagen I levels and enhanced cell attachment and cell cycle progression were observed upon an increase in PDA content. In addition, the ALP activity and osteocalcin of hADSCs cultured on PDA/PLA were significantly higher than seen in those cultured on a pure PLA mat. Moreover, hADSCs cultured on PDA/PLA showed up-regulation of the ang-1 and vWF proteins associated with angiogenesis differentiation. Our results demonstrate that the bio-inspired coating synthetic degradable PLA polymer can be used as a simple technique to render the surfaces of synthetic biodegradable fibers, thus enabling them to direct the specific responses of hADSCs. - Highlights: • A simple method of preparing electrospun poly(lactic acid) nanofibers coated with polydopamine • Enhanced adhesion and proliferation of hADSCs on a PDA/PLA mat • Increased focal adhesion kinase (FAK), collagen I levels, cell attachment and cell cycle progression with a high PDA content • Up-regulation of the Ang-1 and vWF proteins associated with angiogenesis differentiation of hADSCs is observed. • A promising method for bio-inspired surface modification on organic fiber substrates using PDA.

  9. Osteogenesis of human adipose-derived stem cells on poly(dopamine)-coated electrospun poly(lactic acid) fiber mats

    International Nuclear Information System (INIS)

    Lin, Chi-Chang; Fu, Shu-Juan

    2016-01-01

    Electrospinning is a versatile technique to generate large quantities of micro- or nano-fibers from a wide variety of shapes and sizes of polymer. The aim of this study is to develop functionalized electrospun nano-fibers and use a mussel-inspired surface coating to regulate adhesion, proliferation and differentiation of human adipose-derived stem cells (hADSCs). We prepared poly(lactic acid) (PLA) fibers coated with polydopamine (PDA). The morphology, chemical composition, and surface properties of PDA/PLA were characterized by SEM and XPS. PDA/PLA modulated hADSCs' responses in several ways. Firstly, adhesion and proliferation of hADSCs cultured on PDA/PLA were significantly enhanced relative to those on PLA. Increased focal adhesion kinase (FAK) and collagen I levels and enhanced cell attachment and cell cycle progression were observed upon an increase in PDA content. In addition, the ALP activity and osteocalcin of hADSCs cultured on PDA/PLA were significantly higher than seen in those cultured on a pure PLA mat. Moreover, hADSCs cultured on PDA/PLA showed up-regulation of the ang-1 and vWF proteins associated with angiogenesis differentiation. Our results demonstrate that the bio-inspired coating synthetic degradable PLA polymer can be used as a simple technique to render the surfaces of synthetic biodegradable fibers, thus enabling them to direct the specific responses of hADSCs. - Highlights: • A simple method of preparing electrospun poly(lactic acid) nanofibers coated with polydopamine • Enhanced adhesion and proliferation of hADSCs on a PDA/PLA mat • Increased focal adhesion kinase (FAK), collagen I levels, cell attachment and cell cycle progression with a high PDA content • Up-regulation of the Ang-1 and vWF proteins associated with angiogenesis differentiation of hADSCs is observed. • A promising method for bio-inspired surface modification on organic fiber substrates using PDA

  10. Collagen-coated polylactic-glycolic acid (PLGA) seeded with neural-differentiated human mesenchymal stem cells as a potential nerve conduit.

    Science.gov (United States)

    Sulong, Ahmad Fadzli; Hassan, Nur Hidayah; Hwei, Ng Min; Lokanathan, Yogeswaran; Naicker, Amaramalar Selvi; Abdullah, Shalimar; Yusof, Mohd Reusmaazran; Htwe, Ohnmar; Idrus, Ruszymah Bt Hj; Haflah, Nor Hazla Mohamed

    2014-01-01

    Autologous nerve grafts to bridge nerve gaps pose various drawbacks. Nerve tissue engineering to promote nerve regeneration using artificial neural conduits has emerged as a promising alternative. To develop an artificial nerve conduit using collagen-coated polylactic-glycolic acid (PLGA) and to analyse the survivability and propagating ability of the neuro-differentiated human mesenchymal stem cells in this conduit. The PLGA conduit was constructed by dip-molding method and coated with collagen by immersing the conduit in collagen bath. The ultra structure of the conduits were examined before they were seeded with neural-differentiated human mesenchymal stem cells (nMSC) and implanted sub-muscularly on nude mice thighs. The non-collagen-coated PLGA conduit seeded with nMSC and non-seeded non-collagen-coated PLGA conduit were also implanted for comparison purposes. The survivability and propagation ability of nMSC was studied by histological and immunohistochemical analysis. The collagen-coated conduits had a smooth inner wall and a highly porous outer wall. Conduits coated with collagen and seeded with nMSCs produced the most number of cells after 3 weeks. The best conduit based on the number of cells contained within it after 3 weeks was the collagen-coated PLGA conduit seeded with neuro-transdifferentiated cells. The collagen-coated PLGA conduit found to be suitable for attachment, survival and proliferation of the nMSC. Minimal cell infiltration was found in the implanted conduits where nearly all of the cells found in the cell seeded conduits are non-mouse origin and have neural cell markers, which exhibit the biocompatibility of the conduits. The collagen-coated PLGA conduit is biocompatible, non-cytotoxic and suitable for use as artificial nerve conduits.

  11. Demineralized bone matrix and human cancellous bone enhance fixation of porous-coated titanium implants in sheep

    DEFF Research Database (Denmark)

    Babiker, Hassan; Ding, Ming; Overgaard, Søren

    2016-01-01

    matrix (DBM), alone or in combination with allograft or commercially available human cancellous bone (CB), may replace allografts, as they have the capability of inducing new bone and improving implant fixation through enhancing bone ongrowth. The purpose of this study was to investigate the effect...... of DBM alone, DBM with CB, or allograft on the fixation of porous-coated titanium implants. DBM100 and CB produced from human tissue were included. Both materials are commercially available. DBM granules are placed in pure DBM and do not contain any other carrier. Titanium alloy implants, 10 mm long × 10...... mm diameter, were inserted bilaterally into the femoral condyles of eight skeletally mature sheep. Thus, four implants with a concentric gap of 2 mm were implanted in each sheep. The gap was filled with: (a) DBM; (b) DBM:CB at a ratio of 1:3; (c) DBM:allograft at a ratio of 1:3; or (d) allograft...

  12. TiO{sub 2}-enriched polymeric powder coatings support human mesenchymal cell spreading and osteogenic differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Mozumder, Mohammad Sayem; Zhu, Jesse [Department of Chemical and Biochemical Engineering, University of Western Ontario, London, Ontario, N6A 5B9 (Canada); Perinpanayagam, Hiran, E-mail: Hiran.Perinpanayagam@schulich.uwo.ca [Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, N6A 5C1 (Canada)

    2011-06-15

    Novel polymeric powder coatings (PPC) were prepared by ultrafine powder coating technology and shown to support human mesenchymal cell attachment and growth. PPC surfaces enriched with nano-TiO{sub 2} (nTiO{sub 2}) showed enhanced cellular responses, and were compared to commercially pure titanium (cpTi). After cell attachment and growth, osteogenic differentiation and bone matrix formation ensures osseointegration for implantable biomaterials. Therefore, the objective of this study was to determine if mesenchymal cells grown on PPC could undergo osteogenic differentiation by inducing Runx2 and bone matrix proteins, and then initiate mineralization. Atomic force microscopy revealed intricate three-dimensional micro-topographies, and the measures of nano-roughness and porosity were similar for all PPC surfaces. Scanning electron microscopy showed that the cells attached and spread out over all of the surfaces. After 1 week in osteogenic media, RT-PCR analysis showed the induction of Runx2, the up-regulation of type I collagen, and the initial detection of alkaline phosphatase and bone sialoprotein. After 4 weeks, Alizarin Red staining showed mineral deposition. However, cell spreading and osteogenic differentiation were significantly (P < 0.05) higher on the cpTi controls than on the PPC surfaces. Furthermore, spreading and differentiation were consistently higher on the titanium-enriched PPC-2, -3 and -4 than on the titanium-free PPC-1. Therefore, despite the presence of complex micro-topographies and nano-features, titanium-enrichment enhanced the cellular response, and pure titanium still provided the best substrate. These findings confirm the cytocompatibility of these novel polymeric coatings and suggest that titanium-enrichment and nTiO{sub 2} additives may enhance their performance.

  13. The MTT assays of bovine retinal pericytes and human microvascular endothelial cells on DLC and Si-DLC-coated TCPS.

    Science.gov (United States)

    Okpalugo, T I T; McKenna, E; Magee, A C; McLaughlin, J; Brown, N M D

    2004-11-01

    MTT (Tetrazolium)-assay suggests that diamond-like carbon (DLC) and silicon-doped DLC (Si-DLC) films obtained under appropriate deposition parameters are not toxic to bovine retinal pericytes, and human microvascular endothelial cells (HMEC). The observed frequency distributions of the optical density (OD) values indicative of cell viability are near Gaussian-normal distribution. One-way ANOVA indicates that at 0.05 levels the population means are not significantly different for the coated and control samples. The observed OD values depend on the cell line (cell growth/metabolic rate), possibly cell cycle stage, the deposition parameters-bias voltage, ion energy, pressure, argon precleaning, and the dopant. For colored thin films like DLC with room temperature photoconductivity and photoelectric effects, it is important to account for the OD contribution from the coating itself. MTT assay, not surprisingly, seems not to be highly sensitive to interfacial cellular interaction resulting from the change in the film's nanostructure, because the tetrazolium metabolism is mainly intracellular and not interfacial. The thin films were synthesized by 13.56 MHz RF-PECVD using argon and acetylene as source gases, with tetramethylsilane (TMS) vapor introduced for silicon doping. This study could be relevant to biomedical application of the films in the eye, peri-vascular, vascular compartments, and for cell-tissue engineering. (c) 2004 Wiley Periodicals, Inc.

  14. Electrical Properties of PPy-Coated Conductive Fabrics for Human Joint Motion Monitoring

    Directory of Open Access Journals (Sweden)

    Jiyong Hu

    2016-03-01

    Full Text Available Body motion signals indicate several pathological features of the human body, and a wearable human motion monitoring system can respond to human joint motion signal in real time, thereby enabling the prevention and treatment of some diseases. Because conductive fabrics can be well integrated with the garment, they are ideal as a sensing element of wearable human motion monitoring systems. This study prepared polypyrrole conductive fabric by in situ polymerization, and the anisotropic property of the conductive fabric resistance, resistance–strain relationship, and the relationship between resistance and the human knee and elbow movements are discussed preliminarily.

  15. Rezension von: Marcus Recht: Der sympathische Vampir. Visualisierungen von Männlichkeiten in der TV-Serie Buffy. Frankfurt am Main u.a.: Campus Verlag 2011.

    Directory of Open Access Journals (Sweden)

    Hannah Bölling

    2012-08-01

    Full Text Available Marcus Recht leistet als einer der ersten deutschsprachigen Autoren eine ausführliche Analyse der besonderen Darstellung alternativer Geschlechtlichkeit in der TV-Serie Buffy. Mit Hilfe ausführlicher wissenschaftlicher Methodik zeigt Recht auf, dass die Serie sowohl soziale Konstrukte analysiert, widerspiegelt und karikiert als auch eine alternative Geschlechtlichkeit etabliert, welche die männlichen Vampire in einen zur Zeit der Serienausstrahlung gänzlich neuen Gender-Kontext stellt. Viele weitere klassische filmsoziologische Theorien zu Gender-Konstruktion und -Darstellung werden kritisch aufgegriffen und in die Analyse einbezogen. Eine gute Grundlage für Einsteiger/-innen als auch für Kenner/-innen des Feldes, um sich mit dem wissenschaftlichen Potential des popkulturellen Feldes auseinanderzusetzen.

  16. Fructose-Coated Nanodiamonds: Promising Platforms for Treatment of Human Breast Cancer.

    Science.gov (United States)

    Zhao, Jiacheng; Lai, Haiwang; Lu, Hongxu; Barner-Kowollik, Christopher; Stenzel, Martina H; Xiao, Pu

    2016-09-12

    Well-defined carboxyl end-functionalized glycopolymer Poly(1-O-methacryloyl-2,3:4,5-di-O-isopropylidene-β-d-fructopyranose) (Poly(1-O-MAipFru)62) has been prepared via reversible addition-fragmentation chain transfer polymerization and grafted onto the surface of amine-functionalized nanodiamonds via a simple conjugation reaction. The properties of the nanodiamond-polymer hybrid materials ND-Poly(1-O-MAFru)62 are investigated using infrared spectroscopy, thermogravimetric analysis, dynamic light scattering, and transmission electron microscopy. The dispersibility of the nanodiamonds in aqueous solutions is significantly improved after the grafting of the glycopolymer. More interestingly, the cytotoxicity of amine-functionalized nanodiamonds is significantly decreased after decoration with the glycopolymer even at a high concentration (125 μg/mL). The nanodiamonds were loaded with doxorubicin to create a bioactive drug delivery carrier. The release of doxorubicin was faster in media of pH 5 than media of pH 7.4. The nanodiamond drug delivery systems with doxorubicin are used to treat breast cancer cells in 2D and 3D models. Although the 2D cell culture results indicate that all nanodiamonds-doxorubicin complexes are significantly less toxic than free doxorubicin, the glycopolymer-coated nanodiamonds-doxorubicin show higher cytotoxicity than free doxorubicin in the 3D spheroids after treatment for 8 days. The enhanced cytotoxicity of Poly(1-O-MAFru)62-ND-Dox in 3D spheroids may result from the sustained drug release and deep penetration of these nanocarriers, which play a role as a "Trojan Horse". The massive cell death after 8-day incubation with Poly(1-O-MAFru)62-ND-Dox demonstrates that glycopolymer-coated nanodiamonds can be promising platforms for breast cancer therapy.

  17. Anthocyanin contents in the seed coat of black soya bean and their anti-human tyrosinase activity and antioxidative activity.

    Science.gov (United States)

    Jhan, J-K; Chung, Y-C; Chen, G-H; Chang, C-H; Lu, Y-C; Hsu, C-K

    2016-06-01

    The seed coat of black soya bean (SCBS) contains high amount of anthocyanins and shows antioxidant and anti-mushroom tyrosinase activities. The objectives of this study were to analyse the anthocyanins in SCBS with different solvents and to find the relationship between anthocyanin profile with anti-human and anti-mushroom tyrosinase activities. SCBS was extracted with hot water, 50 and 80% ethanol, 50 and 80% acetone and 50 and 80% acidified acetone. Total phenol and total flavonoid contents in the extracts were determined. Anthocyanins in the extracts were analysed using HPLC and LC/MS/MS. A genetically engineered human tyrosinase was used to evaluate the anti-tyrosinase potential of the extracts from SCBS. 80% acetone extract from SCBS obtained the highest total phenol, total flavonoid and cyanidin-3-O-glucoside (C3G) contents among all the extracts, whereas the hot water extract showed the lowest antioxidant contents. Three anthocyanin compounds were found in all the extracts from SCBS, and the analysis of HPLC and LC/MS/MS indicated that they were C3G, delphinidin-3-O-glucoside (D3G) and peonidin-3-O-glucoside (P3G). The ratios of C3G (2.84 mg g(-1) ), D3G (0.34 mg g(-1) ) and P3G (0.35 mg g(-1) ) in 80% acidified acetone extract were 76.6, 9.1 and 9.3%, respectively. All the extracts from SCBS possessed anti-human tyrosinase activity. Moreover, a good correlation was found between the anti-human tyrosinase activities and C3G contents in the extracts. Antioxidants in SCBS also possess anti-human and anti-mushroom tyrosinase activities. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  18. Cost-Effectiveness and Validity Assessment of Cyscope Microscope, Quantitative Buffy Coat Microscope, and Rapid Diagnostic Kit for Malaria Diagnosis among Clinic Attendees in Ibadan, Nigeria

    Directory of Open Access Journals (Sweden)

    Abiodun Ogunniyi

    2016-01-01

    Full Text Available Background. Unavailability of accurate, rapid, reliable, and cost-effective malaria diagnostic instruments constitutes major a challenge to malaria elimination. We validated alternative malaria diagnostic instruments and assessed their comparative cost-effectiveness. Method. Using a cross-sectional study design, 502 patients with malaria symptoms at selected health facilities in Ibadan between January and April 2014 were recruited consecutively. We examined malaria parasites using Cyscope®, QBC, and CareStart™ and results were compared to light microscopy (LM. Validity was determined by assessing sensitivity, specificity, positive predictive value (PPV, and negative predictive value (NPV. Costs per hour of use for instruments and turnaround time were determined. Result. Sensitivity of the instruments was 76.0% (CareStart, 95.0% (Cyscope, and 98.1% (QBC. Specificity was 96.0% (CareStart, 87.3% (Cyscope, and 85.5% (QBC. PPV were 65.2%, 67.5%, and 84.7%, while NPV were 93.6%, 98.6%, and 99.4% for CareStart, Cyscope, and QBC with Kappa values of 0.75 (CI = 0.68–0.82 for CareStart, 0.72 (CI = 0.65–0.78 for Cyscope, and 0.71 (CI = 0.64–0.77 for QBC. Average cost per hour of use was the lowest ($2.04 with the Cyscope. Turnaround time was the fastest with Cyscope (5 minutes. Conclusion. Cyscope fluorescent microscope had the shortest turnaround time and is the most cost-effective of all the malaria diagnostic instruments evaluated.

  19. Tick-borne relapsing fever imported from West Africa: diagnosis by quantitative buffy coat analysis and in vitro culture of Borrelia crocidurae

    NARCIS (Netherlands)

    van Dam, A. P.; van Gool, T.; Wetsteyn, J. C.; Dankert, J.

    1999-01-01

    West African tick-borne relapsing fever (TBRF) is difficult to diagnose due to the low number of spirochetes in the bloodstream of patients. Previously, the causative microorganism, Borrelia crocidurae, had never been cultured in vitro. TBRF was rapidly diagnosed for two patients returning from

  20. Multifunctional devices based on SnO2@rGO-coated fibers for human motion monitoring, ethanol detection, and photo response

    Science.gov (United States)

    Mi, Qing; Wang, Qi; Zang, Siyao; Chai, Zhaoer; Zhang, Jinnan; Ren, Xiaomin

    2018-05-01

    In this study, we developed a multifunctional device based on SnO2@rGO-coated fibers utilizing plasma treatment, dip coating, and microwave irradiation in sequence, and finally realized highly sensitive human motion monitoring, relatively good ethanol detection, and an obvious photo response. Moreover, the high level of comfort and compactness derived from highly elastic and comfortable fabrics contributes to the long-term availability and test accuracy. As an attempt at multifunctional integration of smart clothing, this work provides an attractive and relatively practical research direction.

  1. Binding of human endothelium to Ulex europaeus I-coated Dynabeads: application to the isolation of microvascular endothelium.

    Science.gov (United States)

    Jackson, C J; Garbett, P K; Nissen, B; Schrieber, L

    1990-06-01

    A major problem encountered when isolating human microvascular endothelium is the presence of contaminating cells such as fibroblasts that rapidly over-grow the endothelial cells. We describe here a simple, rapid technique for purifying endothelial cells derived from the microvasculature of neonatal foreskin and osteoarthritic and rheumatoid arthritic synovium. This technique is based on the selective binding of the lectin Ulex europaeus I (UEA I) to the endothelial cell surface via fucose residues. Initially UEA I was covalently bound to tosyl-activated super-paramagnetic polystyrene beads (Dynabeads) by incubation for 24 h at room temperature. Cells were isolated by extracting microvascular segments from enzyme-treated (trypsin and Pronase) cubes of tissue. The mixed population of cells obtained were purified by incubating them at 4 degrees C for 10 min with the UEA I-coated Dynabeads. Endothelium bound to the beads whilst contaminating cells were removed by five washes with HBSS using a magnetic particle concentrator. The endothelial cells thus obtained grew to confluence as a cobblestone-like monolayer and expressed von Willebrand factor antigen. The cells were released from the Dynabeads by the competitive binding of fucose (10 min at 4 degrees C). This new method is simple and reproducible and allows pure human microvascular endothelial cells to be cultured within 2 h of obtaining a specimen.

  2. In vivo IgA coating of anaerobic bacteria in human faeces

    NARCIS (Netherlands)

    vanderWaaij, LA; Limburg, PC; Mesander, G; vanderWaaij, D

    The bacterial flora in the human colon, although extremely diverse, has a relatively stable composition and non-infectious anaerobic bacteria are dominant. The flora forms a pool of numerous different antigens separated from mucosal immunocompetent cells by just a single layer of epithelial cells.

  3. Comparison of the Influence of Phospholipid-Coated Porous Ti-6Al-4V Material on the Osteosarcoma Cell Line Saos-2 and Primary Human Bone Derived Cells

    Directory of Open Access Journals (Sweden)

    Axel Deing

    2016-03-01

    Full Text Available Biomaterial surface functionalization remains of great interest in the promotion of cell osteogenic induction. Previous studies highlighted the positive effects of porous Ti-6Al-4V and phospholipid coating on osteoblast differentiation and bone remodeling. Therefore, the first objective of this study was to evaluate the potential synergistic effects of material porosity and phospholipid coating. Primary human osteoblasts and Saos-2 cells were cultured on different Ti-6Al-4V specimens (mirror-like polished or porous specimens and were coated or not with 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE for three weeks or five weeks. Selected gene expressions (e.g., classical bone markers: alkaline phosphatase, osteocalcin, osteoprotegerin (OPG, receptor activator of nuclear factor kappa-β ligand (RANKL and runt-related transcription factor 2 were estimated in vitro. Furthermore, the expressions of osteocalcin and osteopontin were examined via fluorescent microscopy at five weeks (immunocytochemistry. Consequently, it was observed that phospholipid coating potentiates preferences for low and high porosities in Saos-2 and primary cells, respectively, at the gene and protein levels. Additionally, RANKL and OPG exhibited different gene expression patterns; primary cells showed dramatically increased RANKL expression, whereas OPG expression was decreased in the presence of POPE. A synergistic effect of increased porosity and phospholipid coating was observed in primary osteoblasts in bone remodeling. This study showed the advantage of primary cells over the standard bone cell model.

  4. Structure and barrier properties of human embryonic stem cell-derived retinal pigment epithelial cells are affected by extracellular matrix protein coating.

    Science.gov (United States)

    Sorkio, Anni; Hongisto, Heidi; Kaarniranta, Kai; Uusitalo, Hannu; Juuti-Uusitalo, Kati; Skottman, Heli

    2014-02-01

    Extracellular matrix (ECM) interactions play a vital role in cell morphology, migration, proliferation, and differentiation of cells. We investigated the role of ECM proteins on the structure and function of human embryonic stem cell-derived retinal pigment epithelial (hESC-RPE) cells during their differentiation and maturation from hESCs into RPE cells in adherent differentiation cultures on several human ECM proteins found in native human Bruch's membrane, namely, collagen I, collagen IV, laminin, fibronectin, and vitronectin, as well as on commercial substrates of xeno-free CELLstart™ and Matrigel™. Cell pigmentation, expression of RPE-specific proteins, fine structure, as well as the production of basal lamina by hESC-RPE on different protein coatings were evaluated after 140 days of differentiation. The integrity of hESC-RPE epithelium and barrier properties on different coatings were investigated by measuring transepithelial resistance. All coatings supported the differentiation of hESC-RPE cells as demonstrated by early onset of cell pigmentation and further maturation to RPE monolayers after enrichment. Mature RPE phenotype was verified by RPE-specific gene and protein expression, correct epithelial polarization, and phagocytic activity. Significant differences were found in the degree of RPE cell pigmentation and tightness of epithelial barrier between different coatings. Further, the thickness of self-assembled basal lamina and secretion of the key ECM proteins found in the basement membrane of the native RPE varied between hESC-RPE cultured on compared protein coatings. In conclusion, this study shows that the cell culture substrate has a major effect on the structure and basal lamina production during the differentiation and maturation of hESC-RPE potentially influencing the success of cell integrations and survival after cell transplantation.

  5. Human serum-derived protein removes the need for coating in defined human pluripotent stem cell culture

    Science.gov (United States)

    Pijuan-Galitó, Sara; Tamm, Christoffer; Schuster, Jens; Sobol, Maria; Forsberg, Lars; Merry, Catherine L. R.; Annerén, Cecilia

    2016-01-01

    Reliable, scalable and time-efficient culture methods are required to fully realize the clinical and industrial applications of human pluripotent stem (hPS) cells. Here we present a completely defined, xeno-free medium that supports long-term propagation of hPS cells on uncoated tissue culture plastic. The medium consists of the Essential 8 (E8) formulation supplemented with inter-α-inhibitor (IαI), a human serum-derived protein, recently demonstrated to activate key pluripotency pathways in mouse PS cells. IαI efficiently induces attachment and long-term growth of both embryonic and induced hPS cell lines when added as a soluble protein to the medium at seeding. IαI supplementation efficiently supports adaptation of feeder-dependent hPS cells to xeno-free conditions, clonal growth as well as single-cell survival in the absence of Rho-associated kinase inhibitor (ROCKi). This time-efficient and simplified culture method paves the way for large-scale, high-throughput hPS cell culture, and will be valuable for both basic research and commercial applications. PMID:27405751

  6. Comparative evaluation of various solid phases for the development of coated tube assays for the estimation of progesterone in human serum, bovine serum and bovine milk

    International Nuclear Information System (INIS)

    Karir, Tarveen; Samuel, Grace; Sivaprasad, N.; Venkatesh, Meera

    2009-01-01

    Immobilization of progesterone antibody using three polystyrene surfaces and two progesterone radiotracers for use in the development of a coated tube assay for the evaluation of progesterone levels in human serum, bovine serum and bovine milk was studied. The selection of the solid phase and the tracers were based on the maximum binding, non-specific binding, sensitivity and percentage recovery. Amongst the polystyrene tubes studied, streptavidin coated tubes showed the acceptable assay features such as low non-specific binding (0.5-1.0%), adequate sensitivity (0.13-0.16 ng/ml) and recovery (85-115%) for all the three sample matrices, human serum, bovine serum and bovine milk.

  7. QBC® for the diagnosis of human and canine american visceral leishmaniasis: preliminary data

    Directory of Open Access Journals (Sweden)

    Liarte Daniel B.

    2001-01-01

    Full Text Available "Quantitative Buffy Coat" (QBC® is a direct and fast fluorescent method used for the identification of blood parasites. Since Leishmania chagasi circulates in blood, we decided to test it in American visceral leishmaniasis (AVL. Bone marrow (BM and peripheral blood (PB of 49 persons and PB of 31 dogs were analyzed. QBC® was positive in BM of 11/11 patients with AVL and in 1/6 patients with other diseases. Amastigotes were identified in PB of 18/22 patients with AVL and in none without AVL. The test was positive in 30 out of the 31 seropositive dogs and in 28/28 dogs with Leishmania identified in other tissues. QBC® is a promising method for diagnosis of human AVL, and possibly for the exam of PB of patients with AVL/AIDS, for the control of the cure and for the identification of asymptomatic carriers. Because it is fast and easy to collect and execute, QBC® should be evaluated for programs of reservoir control.

  8. Binding of recombinant HIV coat protein gp120 to human monocytes

    International Nuclear Information System (INIS)

    Finbloom, D.S.; Hoover, D.L.; Meltzer, M.S.

    1991-01-01

    Inasmuch as the exact level of CD4 Ag expression on macrophages is controversial and because HIV may interact with macrophages in a manner different from that on T cells, we analyzed the binding of gp120 to freshly isolated and cultured monocytes. rgp120 was iodinated using the lactoperoxidase method to a sp. act. of 600 Ci/mmol. Highly purified monocytes (greater than 90%) were isolated from the leukapheresed blood of normal volunteers by Ficoll-Hypaque sedimentation followed by countercurrent centrifugal elutriation and cultured 7 days in DMEM supplemented with 1000 U/ml macrophage CSF in 10% human serum. Whereas MOLT/4 cells consistently bound freshly prepared 125I-rgp120 at 80% specificity with 5100 +/- 700 mol/cell, MCSF cultured monocytes bound rgp120 at only 0 to 20% specificity and 420 +/- 200 mol/cell. Most of the radioactivity bound by these cells could not be blocked by the addition of unlabeled rgp120. In contrast, the U937 myeloid cell line bound rgp120 with 50% specificity and about 2500 mol/cell. Whereas the antibody OKT4a (anti-CD4) blocked 80% of the binding on MOLT/4 cells and 50% on U937 cells, binding was only inhibited on the average of 6% on cultured monocytes. When soluble rCD4 was used as an inhibitor, binding to MOLT/4 cells was blocked by 80%. In contrast, binding to cultured monocytes was inhibited by 28%. HIV infectivity was blocked by similar concentrations of OKT4a. These observations suggest that although most binding of gp120 to cultured monocytes is not to the CD4 determinant, several hundred molecules do bind to a CD4-like molecule which promotes virus entry and replication

  9. Magnetic solid-phase extraction based on mesoporous silica-coated magnetic nanoparticles for analysis of oral antidiabetic drugs in human plasma

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Karynne Cristina de; Andrade, Gracielle Ferreira [Centro de Desenvolvimento da Tecnologia Nuclear, CDTN/CNEN, Rua Professor Mário Werneck, s/n. Campus Universitário, Belo Horizonte, MG CEP 30.123-970 (Brazil); Vasconcelos, Ingrid; Oliveira Viana, Iara Maíra de; Fernandes, Christian [Departamento de Produtos Farmacêuticos, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Martins Barros de Sousa, Edésia, E-mail: sousaem@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear, CDTN/CNEN, Rua Professor Mário Werneck, s/n. Campus Universitário, Belo Horizonte, MG CEP 30.123-970 (Brazil)

    2014-07-01

    In the present work, magnetic nanoparticles embedded into mesoporous silica were prepared in two steps: first, magnetite was synthesized by oxidation–precipitation method, and next, the magnetic nanoparticles were coated with mesoporous silica by using nonionic block copolymer surfactants as structure-directing agents. The mesoporous SiO{sub 2}-coated Fe{sub 3}O{sub 4} samples were functionalized using octadecyltrimethoxysilane as silanizing agent. The pure and functionalized silica nanoparticles were physicochemically and morphologically characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), N{sub 2} adsorption, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The resultant magnetic silica nanoparticles were applied as sorbents for magnetic solid-phase extraction (MSPE) of oral antidiabetic drugs in human plasma. Our results revealed that the magnetite nanoparticles were completely coated by well-ordered mesoporous silica with free pores and stable pore walls, and that the structural and magnetic properties of the Fe{sub 3}O{sub 4} nanoparticles were preserved in the applied synthesis route. Indeed, the sorbent material was capable of extracting the antidiabetic drugs from human plasma, being useful for the sample preparation in biological matrices. - Highlights: • SBA-15/Fe{sub 3}O{sub 4} was synthesized and functionalized with octadecyltrimethoxysilane. • Magnetite nanoparticles were completely coated by well-ordered mesoporous silica. • The samples were used as sorbent for magnetic solid-phase extraction (MSPE). • The sorbent material was capable of extracting drugs from human plasma. • The extraction ability makes the material a candidate to be employed as MSPE.

  10. Monolithic calcium phosphate/poly(lactic acid) composite versus calcium phosphate-coated poly(lactic acid) for support of osteogenic differentiation of human mesenchymal stromal cells.

    Science.gov (United States)

    Tahmasebi Birgani, Zeinab; van Blitterswijk, Clemens A; Habibovic, Pamela

    2016-03-01

    Calcium phosphates (CaPs), extensively used synthetic bone graft substitutes, are often combined with other materials with the aim to overcome issues related to poor mechanical properties of most CaP ceramics. Thin ceramic coatings on metallic implants and polymer-ceramic composites are examples of such hybrid materials. Both the properties of the CaP used and the method of incorporation into a hybrid structure are determinant for the bioactivity of the final construct. In the present study, a monolithic composite comprising nano-sized CaP and poly(lactic acid) (PLA) and a CaP-coated PLA were comparatively investigated for their ability to support proliferation and osteogenic differentiation of bone marrow-derived human mesenchymal stromal cells (hMSCs). Both, the PLA/CaP composite, produced using physical mixing and extrusion and CaP-coated PLA, resulting from a biomimetic coating process at near-physiological conditions, supported proliferation of hMSCs with highest rates at PLA/CaP composite. Enzymatic alkaline phosphatase activity as well as the mRNA expression of bone morphogenetic protein-2, osteopontin and osteocalcin were higher on the composite and coated polymer as compared to the PLA control, while no significant differences were observed between the two methods of combining CaP and PLA. The results of this study confirmed the importance of CaP in osteogenic differentiation while the exact properties and the method of incorporation into the hybrid material played a less prominent role.

  11. Relative bioavailability of 13C5-folic acid in pectin-coated folate fortified rice in humans using stable isotope techniques.

    Science.gov (United States)

    de Ambrosis, A; Vishnumohan, S; Paterson, J; Haber, P; Arcot, J

    2017-01-01

    The aim of the study was to measure the relative bioavailability of labeled pteroylglutamic acid (13C5-PteGlu) from a pectin-coated fortified rice in vivo to measure any effect of the edible coating on folic acid bioavailability. Healthy volunteers (N=26) aged 18-39 years received three test meals in three randomized short-term cross-over trials: Trial 1: aqueous 400 μg 13C5-PteGlu, Trial 2: 200 g cooked white rice+400 μg 13C5-PteGlu,Trial 3: 200 g fortified cooked white rice with pectin-coated premix containing 400 μg 13C5-PteGlu. Blood samples were drawn at 0,1,2,5 and 8 h postprandial. The concentration of 13C5-5 methyl-tetrahydrofolate appearing in plasma was quantified using high performance liquid chromatography-mass spectrometry (MS)/MS. For 24 h before baseline estimation and during the area under the curve (AUC) study, the subjects were placed on a low folate diet (∼100 μg/day). The relative bioavailability of the folic acid following Trial 3 was measured by comparing the 13C5-5 methyl-tetrahydrofuran (THF) AUC with Trials 1 and 2. The bioavailability of folic acid in a pectin-coated rice premix was 68.7% (range 47-105) and 86.5% (range 65-115) in uncoated fortified rice relative to aqueous folic acid. This study is the first demonstration of the bioavailability of folate in pectin-coated fortified rice in humans.

  12. Image-Based Phenotypic Screening with Human Primary T Cells Using One-Dimensional Imaging Cytometry with Self-Tuning Statistical-Gating Algorithms.

    Science.gov (United States)

    Wang, Steve S; Ehrlich, Daniel J

    2017-09-01

    The parallel microfluidic cytometer (PMC) is an imaging flow cytometer that operates on statistical analysis of low-pixel-count, one-dimensional (1D) line scans. It is highly efficient in data collection and operates on suspension cells. In this article, we present a supervised automated pipeline for the PMC that minimizes operator intervention by incorporating multivariate logistic regression for data scoring. We test the self-tuning statistical algorithms in a human primary T-cell activation assay in flow using nuclear factor of activated T cells (NFAT) translocation as a readout and readily achieve an average Z' of 0.55 and strictly standardized mean difference of 13 with standard phorbol myristate acetate/ionomycin induction. To implement the tests, we routinely load 4 µL samples and can readout 3000 to 9000 independent conditions from 15 mL of primary human blood (buffy coat fraction). We conclude that the new technology will support primary-cell protein-localization assays and "on-the-fly" data scoring at a sample throughput of more than 100,000 wells per day and that it is, in principle, consistent with a primary pharmaceutical screen.

  13. Experimental infection with the Toxoplasma gondii ME-49 strain in the Brazilian BR-1 mini pig is a suitable animal model for human toxoplasmosis

    Directory of Open Access Journals (Sweden)

    Farlen José Bebber Miranda

    2015-02-01

    Full Text Available Toxoplasma gondii causes toxoplasmosis, a worldwide disease. Experimentation with pigs is necessary for the development of new therapeutic approaches to human diseases. BR-1 mini pigs were intramuscularly infected with T. gondii with tachyzoites (RH strain or orally infected with cysts (ME-49 strain. Haematology and serum biochemistry were analysed and buffy coat cells were inoculated in mice to determine tachyzoite circulation. No alterations were observed in erythrocyte and platelet values; however, band neutrophils increased seven days after infection with ME-49. Serology of the mice inoculated with pig blood leucocytes revealed circulating ME-49 or RH strain tachyzoites in the pigs' peripheral blood at two and seven or nine days post-infection. The tachyzoites were also directly observed in blood smears from the infected pigs outside and inside leucocytes for longer periods. Alanine-aminotransferase was high at days 21 and 32 in the RH infected pigs. After 90 days, the pigs were euthanised and their tissue samples were processed and inoculated into mice. The mice serology revealed the presence of parasites in the hearts, ileums and mesenteric lymph nodes of the pigs. Additionally, cysts in the mice were only observed after pig heart tissue inoculation. The infected pigs presented similar human outcomes with relatively low pathogenicity and the BR-1 mini pig model infected with ME-49 is suitable to monitor experimental toxoplasmosis.

  14. One-Step Purification of Human Skeletal Muscle Myoblasts and Subsequent Expansion Using Laminin-Coated Surface.

    Science.gov (United States)

    Chowdhury, Shiplu Roy; binti Ismail, Annis; Chee, Sia Chye; bin Laupa, Mohd Suffian; binti Jaffri, Fadhlun; Saberi, Salfarina Ezrina Mohmad; Idrus, Ruszymah Bt Hj

    2015-11-01

    Skeletal myoblasts have been extensively used to study muscle growth and differentiation, and were recently tested for their application as cell therapy and as a gene delivery system to treat muscle and nonmuscle diseases. However, contamination of fibroblasts in isolated cells from skeletal muscle is one of the long-standing problems for routine expansion. This study aimed to establish a simple one-step process to purify myoblasts and maintain their purity during expansion. Mixed cells were preplated serially on laminin- and collagen type I-coated surfaces in a different array for 5, 10, and 15 min. Immunocytochemical staining with antibodies specific to myoblasts was performed to evaluate myoblast attachment efficiency, purity, and yield. It was found that laminin-coated surface favors the attachment of myoblasts. Highest myoblast purity of 78.9% ± 6.8% was achieved by 5 min of preplating only on the laminin-coated surface with a yield of 56.9% ± 3.3%. Primary cells, isolated from skeletal muscle (n = 4), confirm the enhancement of purity through preplating on laminin-coated surface for 5 min. Subsequent expansion after preplating enhanced myoblast purity due to an increase in myoblast growth than fibroblasts. Myoblast purity of ∼ 98% was achieved when another preplating was performed during passaging. In conclusion, myoblasts can be purified and efficiently expanded in one step by preplating on laminin-coated surface, which is a simple and robust technique.

  15. Umbelliprenin-coated Fe3O4 magnetite nanoparticles: Antiproliferation evaluation on human Fibrosarcoma cell line (HT-1080)

    International Nuclear Information System (INIS)

    Khorramizadeh, M.R.; Esmail-Nazari, Z.; Zarei-Ghaane, Z.; Shakibaie, M.; Mollazadeh-Moghaddam, K.; Iranshahi, M.; Shahverdi, A.R.

    2010-01-01

    The potential applications of Fe 3 O 4 magnetite nanoparticles (MNPs) in nanomedicine as drug delivery systems are well known. In this study we prepared umbelliprenin-coated Fe 3 O 4 MNPs and evaluated the antiproliferative effect of combination in vitro. After synthesis of Fe 3 O 4 MNPs, particles were characterized by transmission electron microscopy, energy-dispersive spectroscopy, and X-ray diffraction spectroscopy techniques. The natural candidate compound - umbelliprenin- was isolated and identified and umbelliprenin-coated Fe 3 O 4 MNPs were prepared, using precipitation method. The surface chemistry of umbelliprenin-coated Fe 3 O 4 MNPs as well as their thermal decomposition characteristics was examined using Fourier transform infrared spectroscopy and Thermogravimetric Analyzer equipment, respectively. HT-1080 cells were cultured until the logarithmic phase of growth, and MTT assay was successfully carried out to evaluate the possible cytotoxic effects of umbelliprenin-coated Fe 3 O 4 MNPs in viable cells in vitro. The results demonstrated that umbelliprenin has moderate antiproliferative effects with IC 50 value of 50 μg/mL. However, the combination of umbelliprenin and Fe 3 O 4 MNPs showed the IC 50 value of 9 μg/mL. In other words, cell proliferation decreased to the remarkably-low proportion of 45% after treating cells with umbelliprenin-coated Fe 3 O 4 MNPs. This suggests that with the aid of nanoparticles as carriers, natural products may have even broader range of medical applications in future.

  16. Dimorphic ovary differentiation in honeybee (Apis mellifera larvae involves caste-specific expression of homologs of ark and buffy cell death genes.

    Directory of Open Access Journals (Sweden)

    Rodrigo Pires Dallacqua

    Full Text Available The establishment of the number of repeated structural units, the ovarioles, in the ovaries is one of the critical events that shape caste polyphenism in social insects. In early postembryonic development, honeybee (Apis mellifera larvae have a pair of ovaries, each one consisting of almost two hundred ovariole primordia. While practically all these ovarioles continue developing in queen-destined larvae, they undergo massive programmed cell death (PCD in worker-destined larvae. So as to gain insight into the molecular basis of this fundamental process in caste differentiation we used quantitative PCR (qPCR and fluorescent in situ hybridization (FISH to investigate the expression of the Amark and Ambuffy genes in the ovaries of the two honeybee castes throughout the fifth larval instar. These are the homologs of ark and buffy Drosophila melanogaster genes, respectively, involved in activating and inhibiting PCD. Caste-specific expression patterns were found during this time-window defining ovariole number. Amark transcript levels were increased when ovariole resorption was intensified in workers, but remained at low levels in queen ovaries. The transcripts were mainly localized at the apical end of all the worker ovarioles, but appeared in only a few queen ovarioles, thus strongly suggesting a function in mediating massive ovariolar cell death in worker larvae. Ambuffy was mainly expressed in the peritoneal sheath cells covering each ovariole. The levels of Ambuffy transcripts increased earlier in the developing ovaries of queens than in workers. Consistent with a protective role against cell death, Ambuffy transcripts were localized in practically all queen ovarioles, but only in few worker ovarioles. The results are indicative of a functional relationship between the expression of evolutionary conserved cell death genes and the morphological events leading to caste-specific ovary differentiation in a social insect.

  17. One-step derivation of mesenchymal stem cell (MSC-like cells from human pluripotent stem cells on a fibrillar collagen coating.

    Directory of Open Access Journals (Sweden)

    Yongxing Liu

    Full Text Available Controlled differentiation of human embryonic stem cells (hESCs and induced pluripotent stem cells (iPSCs into cells that resemble adult mesenchymal stem cells (MSCs is an attractive approach to obtain a readily available source of progenitor cells for tissue engineering. The present study reports a new method to rapidly derive MSC-like cells from hESCs and hiPSCs, in one step, based on culturing the cells on thin, fibrillar, type I collagen coatings that mimic the structure of physiological collagen. Human H9 ESCs and HDFa-YK26 iPSCs were singly dissociated in the presence of ROCK inhibitor Y-27632, plated onto fibrillar collagen coated plates and cultured in alpha minimum essential medium (alpha-MEM supplemented with 10% fetal bovine serum, 50 uM magnesium L-ascorbic acid phosphate and 100 nM dexamethasone. While fewer cells attached on the collagen surface initially than standard tissue culture plastic, after culturing for 10 days, resilient colonies of homogenous spindle-shaped cells were obtained. Flow cytometric analysis showed that a high percentage of the derived cells expressed typical MSC surface markers including CD73, CD90, CD105, CD146 and CD166 and were negative as expected for hematopoietic markers CD34 and CD45. The MSC-like cells derived from pluripotent cells were successfully differentiated in vitro into three different lineages: osteogenic, chondrogenic, and adipogenic. Both H9 hES and YK26 iPS cells displayed similar morphological changes during the derivation process and yielded MSC-like cells with similar properties. In conclusion, this study demonstrates that bioimimetic, fibrillar, type I collagen coatings applied to cell culture plates can be used to guide a rapid, efficient derivation of MSC-like cells from both human ES and iPS cells.

  18. Chemical speciation of arsenic species in human blood serum by liquid chromatography using a phosphatidylcholine-coated ODS column with detection by ICP-MS

    International Nuclear Information System (INIS)

    Hasegawa, Takuya; Ishise, Jotaro; Fukumoto, Yasuharu; Matsuura, Hirotaka; Zhu, Yanbei; Umemura, Tomonari; Haraguchi, Hiroki; Yamamoto, Kazuhito; Naoe, Tomoki

    2007-01-01

    Chemical speciation of arsenic species in human blood serum was performed by high-performance liquid chromatography/inductively coupled plasma mass spectrometry (HPLC/ICP-MS) with direct sample injection, where an octadecylsilyl silica (ODS) column coated with phosphatidylcholine (PC) (hereafter known as 'PC-coated ODS column') was used as the separation column. In arsenic species analysis, a citrate buffer solution (pH 4.0) was used as the mobile phase, in which the following reagents were added: sodium 1-dodecanesulfonate (SDS), tetramethylammonium hydroxide (TMAH), which are ion-pair reagents to separate inorganic and organic arsenic species, and 3-[(3-cholamidopropyl)-dimethylammonio]-1-propane sulfonate (CHAPS), which is a protein-solubilizing agent to prevent adsorption of proteins on the column. As a result of optimization, five representative arsenic species spiked in human blood serum reference material could be separated from each other within 5 min on the PC-coated ODS column by elution with a 5 mM citrate buffer (pH 4.0) containing 5 mM SDS, 5 mM THAH, and 0.2 mM CHAPS. The detection limits obtained by ICP-MS were 3.1, 2.7, 4.5, 2.5, and 2.5 ng of As g -1 for arsenate (iAs V ), arsenite (iAs III ), monomethylarsonic acid (MMA), dimethylarsenic acid (DMA), and arsenobetaine (AB), respectively, when the injection volume was 20 μL. The present separation system was also applied to speciation analysis of arsenic species in human blood serum collected from a leukemia patient after therapeutic treatment with arsenic. (author)

  19. Initial preclinical safety of non-replicating human endogenous retrovirus envelope protein-coated baculovirus vector-based vaccines against human papillomavirus.

    Science.gov (United States)

    Han, Su-Eun; Kim, Mi-Gyeong; Lee, Soondong; Cho, Hee-Jeong; Byun, Youngro; Kim, Sujeong; Kim, Young Bong; Choi, Yongseok; Oh, Yu-Kyoung

    2013-12-01

    Human endogenous retrovirus (HERV) envelope protein-coated, baculovirus vector-based HPV 16 L1 (AcHERV-HPV16L1) is a non-replicating recombinant baculoviral vaccine. Here, we report an initial evaluation of the preclinical safety of AcHERV-HPV16L1 vaccine. In an acute toxicity study, a single administration of AcHERV-HPV16L1 DNA vaccine given intramuscularly (i.m.) to mice at a dose of 1 × 10(8) plaque-forming units (PFU) did not cause significant changes in body weight compared with vehicle-treated controls. It did cause a brief increase in the weights of some organs on day 15 post-treatment, but by day 30, all organ weights were not significantly different from those in the vehicle-treated control group. No hematological changes were observed on day 30 post-treatment. In a range-finding toxicity study with three doses of 1 × 10(7) , 2 × 10(7) and 5 × 10(7) PFU once daily for 5 days, the group treated with 5 × 10(7) PFU showed a transient decrease in the body weights from day 5 to day 15 post-treatment, but recovery to the levels similar to those in the vehicle-treated control group by post-treatment day 20. Organ weights were slightly higher for lymph nodes, spleen, thymus and liver after repeated dosing with 5 × 10(7) PFU on day 15, but had normalized by day 30. Moreover, repeated administration of AcHERV-HPV16L1 did not induce myosin-specific autoantibody in serum, and did not cause immune complex deposition or tissue damage at injection sites. Taken together, these results provide preliminary evidence of the preclinical safety of AcHERV-based HPV16L1 DNA vaccines in mice. Copyright © 2012 John Wiley & Sons, Ltd.

  20. The influence of gender- and age-related differences in the radiosensitivity of hematopoietic progenitor cells detected in steady-state human peripheral blood

    International Nuclear Information System (INIS)

    Kato, Kengo; Kashiwakura, Ikuo; Kuwabara, Mikinori

    2011-01-01

    To investigate the importance of gender and aging on the individual radiosensitivity of lineage-committed myeloid hematopoietic stem/progenitor cells (HSPCs) detected in mononuclear cells (MNCs) of steady-state human peripheral blood (PB), the clonogenic survival of HPCs, including colony-forming unit-granulocyte macrophage; burst-forming unit-erythroid; colony-forming unit-granulocyte-erythroid-macrophage-megakaryocyte cells derived from MNCs exposed to 0.5 Gy and 2 Gy X-irradiation were estimated. MNCs were prepared from the buffy-coats of 59 healthy individual blood donors. The results showed that large individual differences exist in the number of HSPCs, as well as in the surviving fraction of cells. Furthermore, the number of progenitor cells strongly correlated with their surviving fraction, suggesting that the radiosensitivity of hematopoietic progenitor cells decreases with the number of cells in the 10 5 cells population. A statistically significant negative correlation was observed between the surviving fraction observed at a dose of 0.5 Gy and the age of an individual, however, none of these correlations were observed after 2 Gy irradiation. No statistically significant difference was observed in individual radiosensitivity between males and females at either radiation dose. The present results indicated a correlation between the individual responsiveness of HSPCs to ionizing irradiation, especially to low dose irradiation, and aging. (author)

  1. Protective hybrid coating containing silver, copper and zinc cations effective against human immunodeficiency virus and other enveloped viruses

    Czech Academy of Sciences Publication Activity Database

    Hodek, Jan; Zajícová, V.; Lovětinská-Šlamborová, I.; Stibor, I.; Müllerová, J.; Weber, Jan

    2016-01-01

    Roč. 16, Apr 1 (2016), č. článku 56. ISSN 1471-2180 R&D Projects: GA MŠk(CZ) LK11207 Institutional support: RVO:61388963 Keywords : hybrid coating * virucidal effect * HIV * enveloped viruses Subject RIV: EE - Microbiology, Virology Impact factor: 2.644, year: 2016 http://bmcmicrobiol.biomedcentral.com/articles/10.1186/s12866-016-0675-x

  2. Biological response of human mesenchymal stromal cells to titanium grade 4 implants coated with PCL/ZrO2 hybrid materials synthesized by sol–gel route: in vitro evaluation

    International Nuclear Information System (INIS)

    Catauro, M.; Bollino, F.; Papale, F.; Mozetic, P.; Rainer, A.; Trombetta, M.

    2014-01-01

    The surface modification of implantable materials in order to improve their biological proprieties, including tissue tolerance and osseointegration ability, by means of functional coating deposition is a promising strategy to provide a firm fixation of the implants. In this study, organic/inorganic hybrid materials consisting of an inorganic zirconia-based matrix, in which a biocompatible polymer, poly(ε-caprolactone) (PCL), has been incorporated at different percentages, have been synthesized via sol–gel route. Developed materials have been used to coat titanium grade 4 substrates by means of dip coating technique. Scanning electron microscopy (SEM) analysis of the obtained coatings has shown that films crack-free can be obtained for high levels of PCL. Chemical composition and interactions between organic and inorganic moieties have been studied by Attenuated Total Reflectance Fourier Transform InfraRed spectroscopy. The bone-bonding capability of the nanocomposite films has been evaluated in vitro by examining the appearance of an apatite layer on their surface when soaked in a simulated body fluid by means of SEM equipped with EDS microanalysis. In vitro biocompatibility assessment was performed in combination with human mesenchymal stromal cells (hMSCs). Materials were found to be non-toxic and supporting cell proliferation. Additionally, the coating material was not hampering the differentiation of hMSCs in an osteogenic medium. - Highlights: • ZrO 2 /PCL hybrid coatings on Ti grade 4 were obtained by sol–gel dip coating process. • The PCL acts as a plasticizer and allows us to prepare crack-free coatings. • Independent of PCL amount, the films improve the titanium substrates' bioactivity. • The coatings are non-toxic and supportive of cell proliferation at all compositions. • The coatings don't hamper hMSC differentiation in an osteogenic medium

  3. Biological response of human mesenchymal stromal cells to titanium grade 4 implants coated with PCL/ZrO{sub 2} hybrid materials synthesized by sol–gel route: in vitro evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Catauro, M., E-mail: michelina.catauro@unina2.it [Department of Industrial and Information Engineering, Second University of Naples, Via Roma 29, 81031 Aversa (Italy); Bollino, F.; Papale, F. [Department of Industrial and Information Engineering, Second University of Naples, Via Roma 29, 81031 Aversa (Italy); Mozetic, P.; Rainer, A.; Trombetta, M. [Tissue Engineering Lab, Center for Integrated Research, “Università Campus Bio-Medico di Roma”, via Alvaro del Portillo, 00128 Rome (Italy)

    2014-12-01

    The surface modification of implantable materials in order to improve their biological proprieties, including tissue tolerance and osseointegration ability, by means of functional coating deposition is a promising strategy to provide a firm fixation of the implants. In this study, organic/inorganic hybrid materials consisting of an inorganic zirconia-based matrix, in which a biocompatible polymer, poly(ε-caprolactone) (PCL), has been incorporated at different percentages, have been synthesized via sol–gel route. Developed materials have been used to coat titanium grade 4 substrates by means of dip coating technique. Scanning electron microscopy (SEM) analysis of the obtained coatings has shown that films crack-free can be obtained for high levels of PCL. Chemical composition and interactions between organic and inorganic moieties have been studied by Attenuated Total Reflectance Fourier Transform InfraRed spectroscopy. The bone-bonding capability of the nanocomposite films has been evaluated in vitro by examining the appearance of an apatite layer on their surface when soaked in a simulated body fluid by means of SEM equipped with EDS microanalysis. In vitro biocompatibility assessment was performed in combination with human mesenchymal stromal cells (hMSCs). Materials were found to be non-toxic and supporting cell proliferation. Additionally, the coating material was not hampering the differentiation of hMSCs in an osteogenic medium. - Highlights: • ZrO{sub 2}/PCL hybrid coatings on Ti grade 4 were obtained by sol–gel dip coating process. • The PCL acts as a plasticizer and allows us to prepare crack-free coatings. • Independent of PCL amount, the films improve the titanium substrates' bioactivity. • The coatings are non-toxic and supportive of cell proliferation at all compositions. • The coatings don't hamper hMSC differentiation in an osteogenic medium.

  4. Biocompatibility of Niobium Coatings

    Directory of Open Access Journals (Sweden)

    René Olivares-Navarrete

    2011-09-01

    Full Text Available Niobium coatings deposited by magnetron sputtering were evaluated as a possible surface modification for stainless steel (SS substrates in biomedical implants. The Nb coatings were deposited on 15 mm diameter stainless steel substrates having an average surface roughness of 2 mm. To evaluate the biocompatibility of the coatings three different in vitro tests, using human alveolar bone derived cells, were performed: cellular adhesion, proliferation and viability. Stainless steel substrates and tissue culture plastic were also studied, in order to give comparative information. No toxic response was observed for any of the surfaces, indicating that the Nb coatings act as a biocompatible, bioinert material. Cell morphology was also studied by immune-fluorescence and the results confirmed the healthy state of the cells on the Nb surface. X-ray diffraction analysis of the coating shows that the film is polycrystalline with a body centered cubic structure. The surface composition and corrosion resistance of both the substrate and the Nb coating were also studied by X-ray photoelectron spectroscopy and potentiodynamic tests. Water contact angle measurements showed that the Nb surface is more hydrophobic than the SS substrate.

  5. Biofilm formation on titanium alloy and anatase-Bactercline® coated titanium healing screws: an in vivo human study

    Directory of Open Access Journals (Sweden)

    Antonio Scarano

    2013-03-01

    Full Text Available Aim Bacterial adherence to implants is considered to be an important event in the pathogenesis of bacterial infections. In fact, this infection process is a first stage of peri-implant mucositis and peri-implantitis, and a positive correlation has been found between oral hygiene and marginal bone loss around implants in the edentulous mandible. Surface properties of transgingival implant components are important determinants in bacterial adhesion. The purpose of this study was to characterize the biofilm formation, in vivo, on healing screws made of titanium alloy or coated with a combination of anatase and Bactercline® product. Materials and methods Twenty-five patients, between 21- 37 years, in excellent systemic health, participated in this study. In each of the 25 participants, one anatase-Bactercline® coated healing screw (Test and one titanium alloy (TI6Al4V healing screw (Control were adapted to two different implants. Quantitative and qualitative biofilm formation on healing abutments was analyzed by culture method.Results Bacterial adherence to the two different healing screws used in this study were compared. Statistically significant differences were found between the Control and the Test group for both aerobic and anaerobic bacterial counts (p<0,05. The microflora consisted both of Gram-positive and Gram-negative bacteria, and displayed a high variability. The anaerobic S. intermedius, potentially “pathogenic”, was isolated only from the Control group. Both healing screws harbored primarily Gram-positive rods as Actinomyces spp, A. naeslundii, A. viscosus and the Gram-negative rods (Fusobacterium spp, Prevotella spp, Capnocythophaga spp were mostly found on the Control healing screws.Conclusion Anatase-Bactercline® coated healing screws reduce the number of initially adhering bacteria, formed mainly of Gram-positive microorgnisms, while, on the contrary, the microflora covering the titanium alloy healing screws was, for the

  6. Separation of total lipids on human lipoproteins using surfactant-coated multiwalled carbon nanotubes as pseudostationary phase in capillary electrophoresis.

    Science.gov (United States)

    Su, Mei-Yu; Chen, Yen-Yi; Yang, Jian-Ying; Lin, You-Sian; Lin, Yang-Wei; Liu, Mine-Yine

    2014-04-01

    Surfactant-coated multiwalled carbon nanotubes (MWNTs) were used as pseudostationary phase (PSP) in CE to investigate the total lipids of high-density lipoproteins and low-density lipoproteins. To optimize the CE conditions, several experimental factors including carbon nanotube concentration, bile salt concentration, sodium phosphate (PB) concentration, organic modifier concentration and buffer pH value have been examined. In addition, the CE capillary temperature and applied voltage have also been examined. The optimal separation buffer selected was a mixture of 3.2 mg/L MWNT, 50 mM bile salt, 10 mM PB, 20% 1-propanol, pH 9.5. The optimal capillary temperature and applied voltage selected were 50°C and 20 kV, respectively. Phosphatidyl choline (PC) has been used as a model analyte and investigated by the optimal CE method. The linear range for PC was 0.1-3 mg/mL with a correlation coefficient of 0.9934, and the concentration LOD was 0.055 mg/mL. The optimal CE method has been used to characterize the total lipids of high-density lipoprotein and low-density lipoprotein. At absorbance 200 nm, one major peak and two or three minor peaks showed for the total lipids of lipoproteins within 13 minutes. Resolutions of the total lipids were enhanced using surfactant-coated MWNTs as PSPs in the CE separation buffer. However, resolutions of the total lipids were not enhanced using surfactant-coated single-walled carbon nanotubes as PSPs in the CE separation buffer. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Mixed zirconia calcium phosphate coatings for dental implants: Tailoring coating stability and bioactivity potential

    International Nuclear Information System (INIS)

    Pardun, Karoline; Treccani, Laura; Volkmann, Eike; Streckbein, Philipp; Heiss, Christian; Destri, Giovanni Li; Marletta, Giovanni; Rezwan, Kurosch

    2015-01-01

    Enhanced coating stability and adhesion are essential for long-term success of orthopedic and dental implants. In this study, the effect of coating composition on mechanical, physico-chemical and biological properties of coated zirconia specimens is investigated. Zirconia discs and dental screw implants are coated using the wet powder spraying (WPS) technique. The coatings are obtained by mixing yttria-stabilized zirconia (TZ) and hydroxyapatite (HA) in various ratios while a pure HA coating served as reference material. Scanning electron microscopy (SEM) and optical profilometer analysis confirm a similar coating morphology and roughness for all studied coatings, whereas the coating stability can be tailored with composition and is probed by insertion and dissections experiments in bovine bone with coated zirconia screw implants. An increasing content of calcium phosphate (CP) resulted in a decrease of mechanical and chemical stability, while the bioactivity increased in simulated body fluid (SBF). In vitro experiments with human osteoblast cells (HOB) revealed that the cells grew well on all samples but are affected by dissolution behavior of the studied coatings. This work demonstrates the overall good mechanical strength, the excellent interfacial bonding and the bioactivity potential of coatings with higher TZ contents, which provide a highly interesting coating for dental implants. - Highlights: • Different ratios of zirconia (TZ) and calcium phosphate (CP) were deposited on zirconia substrates. • Enhancement of TZ content in mixed coatings increased coating stability. • Enhancement of CP content in mixed coatings increased bioactivity. • All tested coating compositions were non-toxic

  8. Mixed zirconia calcium phosphate coatings for dental implants: Tailoring coating stability and bioactivity potential

    Energy Technology Data Exchange (ETDEWEB)

    Pardun, Karoline [University of Bremen, Advanced Ceramics, Am Biologischen Garten 2, 28359 Bremen (Germany); Treccani, Laura, E-mail: treccani@uni-bremen.de [University of Bremen, Advanced Ceramics, Am Biologischen Garten 2, 28359 Bremen (Germany); Volkmann, Eike [University of Bremen, Advanced Ceramics, Am Biologischen Garten 2, 28359 Bremen (Germany); Streckbein, Philipp [University Hospital, Justus-Liebig-University Giessen, Department of Cranio-Maxillo-Facial Surgery, Klinikstrasse 33, 35385 Giessen (Germany); Heiss, Christian [University Hospital of Giessen-Marburg, Department of Trauma Surgery, Rudolf-Buchheim-Strasse 7, 35385 Giessen, Germany, (Germany); Laboratory of Experimental Surgery, Kerkraderstrasse 9, 35392 Giessen (Germany); Destri, Giovanni Li; Marletta, Giovanni [Laboratory for Molecular Surfaces and Nanotechnology (LAMSUN), Department of Chemistry, University of Catania and CSGI, Viale A. Doria 6, 95125 Catania (Italy); Rezwan, Kurosch [University of Bremen, Advanced Ceramics, Am Biologischen Garten 2, 28359 Bremen (Germany)

    2015-03-01

    Enhanced coating stability and adhesion are essential for long-term success of orthopedic and dental implants. In this study, the effect of coating composition on mechanical, physico-chemical and biological properties of coated zirconia specimens is investigated. Zirconia discs and dental screw implants are coated using the wet powder spraying (WPS) technique. The coatings are obtained by mixing yttria-stabilized zirconia (TZ) and hydroxyapatite (HA) in various ratios while a pure HA coating served as reference material. Scanning electron microscopy (SEM) and optical profilometer analysis confirm a similar coating morphology and roughness for all studied coatings, whereas the coating stability can be tailored with composition and is probed by insertion and dissections experiments in bovine bone with coated zirconia screw implants. An increasing content of calcium phosphate (CP) resulted in a decrease of mechanical and chemical stability, while the bioactivity increased in simulated body fluid (SBF). In vitro experiments with human osteoblast cells (HOB) revealed that the cells grew well on all samples but are affected by dissolution behavior of the studied coatings. This work demonstrates the overall good mechanical strength, the excellent interfacial bonding and the bioactivity potential of coatings with higher TZ contents, which provide a highly interesting coating for dental implants. - Highlights: • Different ratios of zirconia (TZ) and calcium phosphate (CP) were deposited on zirconia substrates. • Enhancement of TZ content in mixed coatings increased coating stability. • Enhancement of CP content in mixed coatings increased bioactivity. • All tested coating compositions were non-toxic.

  9. New Functionalized Sol-Gel Hybrid Sorbent Coating for Stir Bar Sorptive Extraction of Selected Non-Steroidal Anti Inflammatory Drugs in Human Urine Samples

    International Nuclear Information System (INIS)

    Mashkurah Abd Rahim; Wan Aini Wan Ibrahim; Zainab Ramli; Mohd Marsin Sanagi

    2015-01-01

    A new sol-gel hybrid material, methyltrimethoxysilane-cyanopropyltriethoxysilane (MTMOS-CNPrTEOS) was successfully synthesized and used as a coating material in stir bar sorptive extraction (SBSE) of selected non-steroidal anti-inflammatory drugs (NSAIDs) in urine samples. The MTMOS-CNPrTEOS hybrid was synthesized by hydrolysis and condensation of MTMOS and CNPrTEOS in the presence of trifluoroacetic acid as catalyst via sol-gel method. Several factors influencing the synthesized sol-gel hybrid MTMOS-CNPrTEOS process such as mole ratio of MTMOS-CNPrTEOS, NaOH concentrations as etching solution, etching time, coating time and water content were investigated and optimized in this study. The optimum synthesis conditions obtained were 1:1 mol ratio of MTMOS-CNPrTEOS, 1 M NaOH as etching solution, 60 min etching time, 2 h coating time and 6 mmol water. The sol-gel hybrid MTMOS-CNPrTEOS synthesized under the optimum conditions was used to determine selected NSAIDs in human urine samples using normal stacking mode capillary electrophoresis with ultraviolet detection. MTMOS-CNPrTEOS SBSE method demonstrated good linearity (60 to 20,000 μg L -1 ) with excellent coefficient of determination (r 2 > 0.9990). The sol-gel hybrid MTMOS-CNPrTEOS SBSE method showed low limit of detection (35 - 41 μg L -1 ) with good precision (RSD < 6 %, n = 3) and excellent extraction recoveries (83.5 - 98.9 %) for the selected NSAIDs. The sol-gel hybrid MTMOS-CNPrTEOS SBSE method demonstrated good potential as an alternative sorbent in SBSE method for NSAIDs. (author)

  10. Osteogenic potential of human adipose-derived stromal cells on 3-dimensional mesoporous TiO{sub 2} coating with magnesium impregnation

    Energy Technology Data Exchange (ETDEWEB)

    Cecchinato, Francesca, E-mail: francesca.cecchinato@mah.se [Department of Prosthodontics, Faculty of Odontology, Malmö University, Malmö (Sweden); Karlsson, Johan [Department of Chemical and Biological Engineering, Applied Surface Chemistry, Chalmers University of Technology, Gothenburg (Sweden); Ferroni, Letizia; Gardin, Chiara [Department of Histology, Microbiology, and Medical Biotechnologies, University of Padova, Padova (Italy); Galli, Silvia; Wennerberg, Ann [Department of Prosthodontics, Faculty of Odontology, Malmö University, Malmö (Sweden); Zavan, Barbara [Department of Histology, Microbiology, and Medical Biotechnologies, University of Padova, Padova (Italy); Andersson, Martin [Department of Chemical and Biological Engineering, Applied Surface Chemistry, Chalmers University of Technology, Gothenburg (Sweden); Jimbo, Ryo [Department of Prosthodontics, Faculty of Odontology, Malmö University, Malmö (Sweden); Department of Applied Prosthodontics, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki (Japan)

    2015-07-01

    The aim of this study was to evaluate the osteogenic response of human adipose-derived stromal cells (ADScs) to mesoporous titania (TiO{sub 2}) coatings produced with evaporation-induced self-assembly method (EISA) and loaded with magnesium. Our emphasis with the magnesium release functionality was to modulate progenitor cell osteogenic differentiation under standard culture conditions. Osteogenic properties of the coatings were assessed for stromal cells by means of scanning electron microscopy (SEM) imaging, colorimetric mitochondrial viability assay (MTT), colorimetric alkaline phosphates activity (ALP) assay and real time RT-polymerase chain reaction (PCR). Using atomic force microscopy (AFM) it was shown that the surface expansion area (S{sub dr}) was strongly enhanced by the presence of magnesium. From MTT results it was shown that ADSc viability was significantly increased on mesoporous surfaces compared to the non-porous one at a longer cell culture time. However, no differences were observed between the magnesium impregnated and non-impregnated surfaces. The alkaline phosphatase activity confirmed that ADSc started to differentiate into the osteogenic phenotype after 2 weeks of culturing. The gene expression profile at 2 weeks of cell growth showed that such coatings were capable to incorporate specific osteogenic markers inside their interconnected nano-pores and, at 3 weeks, ADSc differentiated into osteoblasts. Interestingly, magnesium significantly promoted the osteopontin gene expression, which is an essential gene for the early biomaterial–cell osteogenic interaction. - Highlights: • The magnesium loading presents a transitory effect on mesoporous TiO{sub 2} surface topography • The mesoporous structure promotes cellular attachment and spreading • The mesoporous structure activates osteogenesis of mesenchymal stem cells in absence of osteogenic promoters • The physical adsorbed magnesium is suggested to be involved in the expression of

  11. Osteogenic potential of human adipose-derived stromal cells on 3-dimensional mesoporous TiO2 coating with magnesium impregnation

    International Nuclear Information System (INIS)

    Cecchinato, Francesca; Karlsson, Johan; Ferroni, Letizia; Gardin, Chiara; Galli, Silvia; Wennerberg, Ann; Zavan, Barbara; Andersson, Martin; Jimbo, Ryo

    2015-01-01

    The aim of this study was to evaluate the osteogenic response of human adipose-derived stromal cells (ADScs) to mesoporous titania (TiO 2 ) coatings produced with evaporation-induced self-assembly method (EISA) and loaded with magnesium. Our emphasis with the magnesium release functionality was to modulate progenitor cell osteogenic differentiation under standard culture conditions. Osteogenic properties of the coatings were assessed for stromal cells by means of scanning electron microscopy (SEM) imaging, colorimetric mitochondrial viability assay (MTT), colorimetric alkaline phosphates activity (ALP) assay and real time RT-polymerase chain reaction (PCR). Using atomic force microscopy (AFM) it was shown that the surface expansion area (S dr ) was strongly enhanced by the presence of magnesium. From MTT results it was shown that ADSc viability was significantly increased on mesoporous surfaces compared to the non-porous one at a longer cell culture time. However, no differences were observed between the magnesium impregnated and non-impregnated surfaces. The alkaline phosphatase activity confirmed that ADSc started to differentiate into the osteogenic phenotype after 2 weeks of culturing. The gene expression profile at 2 weeks of cell growth showed that such coatings were capable to incorporate specific osteogenic markers inside their interconnected nano-pores and, at 3 weeks, ADSc differentiated into osteoblasts. Interestingly, magnesium significantly promoted the osteopontin gene expression, which is an essential gene for the early biomaterial–cell osteogenic interaction. - Highlights: • The magnesium loading presents a transitory effect on mesoporous TiO 2 surface topography • The mesoporous structure promotes cellular attachment and spreading • The mesoporous structure activates osteogenesis of mesenchymal stem cells in absence of osteogenic promoters • The physical adsorbed magnesium is suggested to be involved in the expression of osteopontin

  12. Human serum albumin supported lipid patterns for the targeted recognition of microspheres coated by membrane based on ss-DNA hybridization

    International Nuclear Information System (INIS)

    Zhang Xiaoming; He Qiang; Cui Yue; Duan Li; Li Junbai

    2006-01-01

    Human serum albumin (HSA) patterns have been successfully fabricated for the deposition of lipid bilayer, 1,2-dimyristoyl-sglycerophosphate (DMPA), by making use of the micro-contact printing (μCP) technique and liposome fusion. Confocal laser scanning microscopy (CLSM) results indicate that lipid bilayer has been assembled in HSA patterns with a good stability. Such well-defined lipid patterns formed on HSA surface create possibility to incorporate specific components like channels or receptors for specific recognition. In view of this, microspheres coated with lipid membranes were immobilized in HSA-supported lipid patterns via the hybridization of complementary ss-DNAs. This procedure enables to transfer solid materials to a soft surface through a specific recognition

  13. Flexible and Compressible PEDOT:PSS@Melamine Conductive Sponge Prepared via One-Step Dip Coating as Piezoresistive Pressure Sensor for Human Motion Detection.

    Science.gov (United States)

    Ding, Yichun; Yang, Jack; Tolle, Charles R; Zhu, Zhengtao

    2018-05-09

    Flexible and wearable pressure sensor may offer convenient, timely, and portable solutions to human motion detection, yet it is a challenge to develop cost-effective materials for pressure sensor with high compressibility and sensitivity. Herein, a cost-efficient and scalable approach is reported to prepare a highly flexible and compressible conductive sponge for piezoresistive pressure sensor. The conductive sponge, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)@melamine sponge (MS), is prepared by one-step dip coating the commercial melamine sponge (MS) in an aqueous dispersion of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). Due to the interconnected porous structure of MS, the conductive PEDOT:PSS@MS has a high compressibility and a stable piezoresistive response at the compressive strain up to 80%, as well as good reproducibility over 1000 cycles. Thereafter, versatile pressure sensors fabricated using the conductive PEDOT:PSS@MS sponges are attached to the different parts of human body; the capabilities of these devices to detect a variety of human motions including speaking, finger bending, elbow bending, and walking are evaluated. Furthermore, prototype tactile sensory array based on these pressure sensors is demonstrated.

  14. Wipes coated with a singlet-oxygen-producing photosensitizer are effective against human influenza virus but not against norovirus

    NARCIS (Netherlands)

    Verhaelen, Katharina; Bouwknegt, Martijn; Rutjes, Saskia; de Roda Husman, Ana Maria; Duizer, Erwin

    2014-01-01

    Transmission of enteric and respiratory viruses, including human norovirus (hNoV) and human influenza virus, may involve surfaces. In food preparation and health care settings, surfaces are cleaned with wipes; however, wiping may not efficiently reduce contamination or may even spread viruses,

  15. Hard coatings

    International Nuclear Information System (INIS)

    Dan, J.P.; Boving, H.J.; Hintermann, H.E.

    1993-01-01

    Hard, wear resistant and low friction coatings are presently produced on a world-wide basis, by different processes such as electrochemical or electroless methods, spray technologies, thermochemical, CVD and PVD. Some of the most advanced processes, especially those dedicated to thin film depositions, basically belong to CVD or PVD technologies, and will be looked at in more detail. The hard coatings mainly consist of oxides, nitrides, carbides, borides or carbon. Over the years, many processes have been developed which are variations and/or combinations of the basic CVD and PVD methods. The main difference between these two families of deposition techniques is that the CVD is an elevated temperature process (≥ 700 C), while the PVD on the contrary, is rather a low temperature process (≤ 500 C); this of course influences the choice of substrates and properties of the coating/substrate systems. Fundamental aspects of the vapor phase deposition techniques and some of their influences on coating properties will be discussed, as well as the very important interactions between deposit and substrate: diffusions, internal stress, etc. Advantages and limitations of CVD and PVD respectively will briefly be reviewed and examples of applications of the layers will be given. Parallel to the development and permanent updating of surface modification technologies, an effort was made to create novel characterisation methods. A close look will be given to the coating adherence control by means of the scratch test, at the coating hardness measurement by means of nanoindentation, at the coating wear resistance by means of a pin-on-disc tribometer, and at the surface quality evaluation by Atomic Force Microscopy (AFM). Finally, main important trends will be highlighted. (orig.)

  16. Protective Coatings

    Science.gov (United States)

    1980-01-01

    General Magnaplate Corporation's pharmaceutical machine is used in the industry for high speed pressing of pills and capsules. Machine is automatic system for molding glycerine suppositories. These machines are typical of many types of drug production and packaging equipment whose metal parts are treated with space spinoff coatings that promote general machine efficiency and contribute to compliance with stringent federal sanitation codes for pharmaceutical manufacture. Collectively known as "synergistic" coatings, these dry lubricants are bonded to a variety of metals to form an extremely hard slippery surface with long lasting self lubrication. The coatings offer multiple advantages; they cannot chip, peel or be rubbed off. They protect machine parts from corrosion and wear longer, lowering maintenance cost and reduce undesired heat caused by power-robbing friction.

  17. Downregulation of host tryptophan-aspartate containing coat (TACO gene restricts the entry and survival of Leishmania donovani in human macrophage model

    Directory of Open Access Journals (Sweden)

    Venkateswara Reddy Gogulamudi

    2015-10-01

    Full Text Available Leishmania are obligate intracellular protozoan parasites of mammalian hosts. Promastigotes of Leishmania are internalized by macrophages and transformed into amastigotes in phagosomes, and replicate in phagolysosomes. Phagosomal maturation arrest is known to play a central role in the survival of pathogenic Leishmania within activated macrophages. Recently, tryptophan-aspartate containing coat (TACO gene has been recognized as playing a crucial role in the survival of Mycobacterium tuberculosis within human macrophages by arresting the phagosome maturation process. We postulated that a similar association of TACO gene with phagosomes would prevent the vacuole from maturation in the case of Leishmania. In this study we attempted to define the effect of TACO gene downregulation on the uptake/survival of Leishmania donovani intracellularly, by treatment with Vitamin D3/Retinoic acid (RA & Chenodeoxycholic acid (CDCA/Retinoic acid (RA combinations in human THP-1 macrophages (in vitro. Treatment with these molecules downregulated the TACO gene in macrophages, resulting in reduced parasite load and marked reduction of disease progression in L. donovani infected macrophages. Taken together, these results suggest that TACO gene downregulation may play a role in subverting macrophage machinery in establishing the L.donovani replicative niche inside the host. Our study is the first to highlight the importantrole of the TACO gene in Leishmania entry, and to identify TACO gene downregulation as potential drug target against leishmaniasis.

  18. Commensal oral bacteria antigens prime human dendritic cells to induce Th1, Th2 or Treg differentiation.

    Science.gov (United States)

    Kopitar, A N; Ihan Hren, N; Ihan, A

    2006-02-01

    In various immunopathologic conditions, bacterial flora induce an immune response which results in inflammatory manifestations, e.g. periapical granuloma. Dendritic cells provide the main orchestration of specific immune responses. The aim of our study was to test the capacity of distinct oral bacterial antigens (prepared from Streptococcus mitis, Propionibacterium acnes, and Bacteroides spp.) to prime human dendritic cells for stimulation of the T-lymphocyte response. To assess the T-lymphocyte response, the expression of CD25, CD69, intracellular interferon gamma (cIFN-gamma), and intracellular interleukin 4 (cIL-4) was determined. Dendritic cells were prepared from leukocyte buffy coat from healthy blood donors. Monocytes were stimulated with IL-4 and GM-CSF and dendritic cells activated with bacterial lysates. Cell suspensions contained up to 90% dendritic cells, which represented 2-12% of the initial number of mononuclear cells. Lymphocyte subsets that developed in lymphocyte cultures after 1 week of stimulation were analyzed by flow cytometry. Dendritic cells, primed with antigens of Bacteroides fragilis have shown significantly higher activation and expression of intercellular IFN-gamma by T lymphocytes compared to negative controls. The dendritic cells primed with antigens of P. acnes had no effect on T-lymphocyte activation or cytokine production; instead they induced differentiation of T lymphocytes into CD25bright cells (regulatory T cells) with a potentially inhibitory effect on immune response. Dendritic cells primed with antigens of S. mitis induced increased expression of cIL-4. We conclude that commensal oral bacteria antigens prepared from B. fragilis, S. mitis, and P. acnes prime human dendritic cells to induce Th1, Th2, and T(reg) differentiation, respectively. This may advance our understanding of immunopathologic manifestations in the oral cavity and offer new possibilities for redirecting immune responses in mucosal vaccination.

  19. Aliphatic alcohols of illegally produced spirits can act synergistically on superoxide-anion production by human granulocytes.

    Science.gov (United States)

    Arnyas, Ervin M; Pál, László; Kovács, Csilla; Adány, Róza; McKee, Martin; Szűcs, Sándor

    2012-10-01

    Aliphatic alcohols present in illegally produced spirits in a large number of low and middle income countries have been implicated in the etiology of chronic liver disease and cirrhosis. Previous studies have confirmed that chronic alcoholism can lead to increased susceptibility to infectious diseases. Reduced superoxide-anion (O(2)·(-)) production by granulocytes could provide a mechanism by which antimicrobial defense is impaired in alcoholics. In vitro experiments have also demonstrated that ethanol can inhibit granulocyte O(2)·(-) generation. Aliphatic alcohols consumed as contaminants of illicit spirits may also influence O(2)·(-) production thereby contributing to a decrease in microbicidal activity. The aim of this study was to investigate this possibility. It measured the O(2)·(-) production by human granulocytes following treatment of the cells with aliphatic alcohol contaminants found in illicit spirits. Granulocytes were isolated from human buffy coats with centrifugal elutriation and then treated with individual aliphatic alcohols and their mixture. The O(2)·(-) production was stimulated with phorbol-12-13-dibutyrate and N-formyl-methionyl-leucyl-phenylalanine (FMLP) and measured by superoxide dismutase inhibitable reduction of ferricytochrome c. Aliphatic alcohols of illegally produced spirits inhibited the FMLP-induced O(2)·(-) production in a concentration dependent manner. They suppressed O(2)·(-) generation at 2.5-40 times lower concentrations when combined than when tested individually. Aliphatic alcohols found in illegally produced spirits can inhibit FMLP-induced O(2)·(-) production by granulocytes in a concentration-dependent manner. Due to their synergistic effects, it is possible that, in combination with ethanol, they may inhibit O(2)·(-) formation in heavy episodic drinkers.

  20. Human Invariant Natural Killer T Cells Respond to Antigen-Presenting Cells Exposed to Lipids from Olea europaea Pollen.

    Science.gov (United States)

    Abos Gracia, Beatriz; López Relaño, Juan; Revilla, Ana; Castro, Lourdes; Villalba, Mayte; Martín Adrados, Beatriz; Regueiro, Jose Ramon; Fernández-Malavé, Edgar; Martínez Naves, Eduardo; Gómez Del Moral, Manuel

    2017-01-01

    Allergic sensitization might be influenced by the lipids present in allergens, which can be recognized by natural killer T (NKT) cells on antigen-presenting cells (APCs). The aim of this study was to analyze the effect of olive pollen lipids in human APCs, including monocytes as well as monocyte-derived macrophages (Mϕ) and dendritic cells (DCs). Lipids were extracted from olive (Olea europaea) pollen grains. Invariant (i)NKT cells, monocytes, Mϕ, and DCs were obtained from buffy coats of healthy blood donors, and their cell phenotype was determined by flow cytometry. iNKT cytotoxicity was measured using a lactate dehydrogenase assay. Gene expression of CD1A and CD1D was performed by RT-PCR, and the production of IL-6, IL-10, IL-12, and TNF-α cytokines by monocytes, Mϕ, and DCs was measured by ELISA. Our results showed that monocytes and monocyte-derived Mϕ treated with olive pollen lipids strongly activate iNKT cells. We observed several phenotypic modifications in the APCs upon exposure to pollen-derived lipids. Both Mϕ and monocytes treated with olive pollen lipids showed an increase in CD1D gene expression, whereas upregulation of cell surface CD1d protein occurred only in Mϕ. Furthermore, DCs differentiated in the presence of human serum enhance their surface CD1d expression when exposed to olive pollen lipids. Finally, olive pollen lipids were able to stimulate the production of IL-6 but downregulated the production of lipopolysaccharide- induced IL-10 by Mϕ. Olive pollen lipids alter the phenotype of monocytes, Mϕ, and DCs, resulting in the activation of NKT cells, which have the potential to influence allergic immune responses. © 2017 S. Karger AG, Basel.

  1. Transport and release of colloidal 3-mercaptopropionic acid-coated CdSe–CdS/ZnS core-multishell quantum dots in human umbilical vein endothelial cells

    Directory of Open Access Journals (Sweden)

    Fontana JM

    2017-12-01

    Full Text Available Jacopo M Fontana,1 Huijuan Yin,1 Yun Chen,2 Ricardo Florez,1 Hjalmar Brismar,1 Ying Fu1 1Section of Cellular Biophysics, Department of Applied Physics, Royal Institute of Technology, Science for Life Laboratory, Solna, 2Department of Molecular and Clinical Medicine/Clinical Physiology, The Sahlgrenska Academy and University Hospital, University of Gothenburg, Gothenburg, Sweden Abstract: Colloidal semiconductor quantum dots (QDs have been extensively researched and developed for biomedical applications, including drug delivery and biosensing assays. Hence, it is pivotal to understand their behavior in terms of intracellular transport and toxicological effects. In this study, we focused on 3-mercaptopropionic acid-coated CdSe-CdS/ZnS core-multishell quantum dots (3MPA-QDs converted from the as-grown octadecylamine-coated quantum dots (ODA-QDs and their direct and dynamic interactions with human umbilical vein endothelial cells (HUVECs. Live cell imaging using confocal fluorescence microscopy showed that 3MPA-QDs first attached to and subsequently aggregated on HUVEC plasma membrane ~25 min after QD deposition. The aggregated QDs started being internalized at ~2 h and reached their highest internalization degree at ~24 h. They were released from HUVECs after ~48 h. During the 48 h period, the HUVECs responded normally to external stimulations, grew, proliferated and wound healed without any perceptible apoptosis. Furthermore, 1 3MPA-QDs were internalized in newly formed LysoTracker-stained early endosomes; 2 adenosine 5'-triphosphate-induced [Ca2+]i modulation caused a transient decrease in the fluorescence of 3MPA-QDs that were attached to the plasma membrane but a transient increase in the internalized 3MPA-QDs; and 3 fluorescence signal modulations of co-stained LysoTracker and QDs induced by the lysosomotropic agent Gly-Phe-β-naphthylamide were spatially co-localized and temporally synchronized. Our findings suggest that 3MPA

  2. Biophysical and biological contributions of polyamine-coated carbon nanotubes and bidimensional buckypapers in the delivery of miRNAs to human cells

    Directory of Open Access Journals (Sweden)

    Celluzzi A

    2017-12-01

    Full Text Available Antonella Celluzzi,1,* Alessandro Paolini,1,* Valentina D’Oria,1 Roberta Risoluti,2 Stefano Materazzi,2 Marco Pezzullo,1 Stefano Casciardi,3 Simona Sennato,4 Federico Bordi,4 Andrea Masotti1 1Bambino Gesù Children’s Hospital, IRCCS, Research Laboratories, 2Department of Chemistry, Sapienza University of Rome, 3Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, National Institution for Insurance Against Accidents at Work (INAIL Research, Monte Porzio Catone, 4CNR-ISC UOS Roma, Department of Physics, Sapienza University of Rome, Roma, Italy *These authors contributed equally to this work Abstract: Recent findings in nanomedicine have revealed that carbon nanotubes (CNTs can be used as potential drug carriers, therapeutic agents and diagnostics tools. Moreover, due to their ability to cross cellular membranes, their nanosize dimension, high surface area and relatively good biocompatibility, CNTs have also been employed as a novel gene delivery vector system. In our previous work, we functionalized CNTs with two polyamine polymers, polyethyleneimine (PEI and polyamidoamine dendrimer (PAMAM. These compounds have low cytotoxicity, ability to conjugate microRNAs (such as miR-503 and, at the same time, transfect efficiently endothelial cells. The parameters contributing to the good efficiency of transfection that we observed were not investigated in detail. In fact, the diameter and length of CNTs are important parameters to be taken into account when evaluating the effects on drug delivery efficiency. In order to investigate the biophysical and biological contributions of polymer-coated CNTs in delivery of miRNAs to human cells, we decided to investigate three different preparations, characterized by different dimensions and aspect ratios. In particular, we took into account very small CNTs, a suspension of CNTs starting from the commercial product and a 2D material based on CNTs (ie, buckypapers [BPs] to examine the

  3. Interaction of human osteoblast-like Saos-2 cells with stainless steel coated by silicalite-1 films

    Czech Academy of Sciences Publication Activity Database

    Jirka, Ivan; Vandrovcová, Marta; Plšek, Jan; Bouša, Milan; Brabec, Libor; Dragounová, Helena; Bačáková, Lucie

    2017-01-01

    Roč. 76, JUL 2017 (2017), s. 775-781 ISSN 0928-4931 R&D Projects: GA ČR(CZ) GA16-02681S Institutional support: RVO:61388955 ; RVO:67985823 Keywords : silicalite-1 film * biocompatibility * human osteoblast-like Saos-2 cells Subject RIV: CF - Physical ; Theoretical Chemistry; EI - Biotechnology ; Bionics (FGU-C) OBOR OECD: Physical chemistry; Biomaterials (as related to medical implants, devices, sensors) (FGU-C)

  4. Metabolic Activation of the Organic Fraction Coated Onto Air Pollution PM2.5 and its Genotoxicity in a Co Culture Model of Human Lung Cells

    International Nuclear Information System (INIS)

    Abbas, I; Garcon, G; Billet, S.; Verdin, A.; Escande, F.; Saint-Georges, F.; Mulliez, Ph.; Gosset, P.; Shirali, P.

    2011-01-01

    Air pollution Particulate Matter (PM 2 .5) is described as one of the major risk factors affecting human health. Hence, the objective of our research project was to evaluate the lung toxicity of PM 2 .5 collected in Dunkerque (France), through the study of the metabolic activation of its organic fraction (e.g. Polycyclic Aromatic Hydrocarbons, PAHs; Volatile Organic Compounds, VOCs) and its genotoxicity in two human cell models: embryonic lung epithelial L132 cells and Alveolar Macrophages (AM) isolated from bronchiolo-alveolar lavages of healthy outpatients, in mono- and/or coculture. The coculture system we used allowed the direct exposure of AM to PM 2 .5, and the interaction between the two cell types only through soluble factor diffusion. Exposure to Dunkerque City's PM 2 .5 induced the gene expression of phase I and phase II enzymes (e.g. CYP1A1, CYP2E1, CYP2F1, NQO1, GSTπ1, GSTμ3) involved in the metabolic activation of PAHS and/or VOCS, in AM, in mono- and coculture, and in L132 cells, only in monoculture. Taken together, these results reinforced the key role of AM in lung defenses, and indicated that particles, as physical vector of the penetration and retention of coated-PAHS and/or VOCS within cells, enabled them to exert a durable toxicity. DNA bulky adduct formation was also reported not only in Dunkerque City's PM 2 .5-exposed AM, in mono- and coculture, but also in L132 cells from PAH-exposed coculture. Loss of Heterozygosity (LOH) and/or MicroSatellite Instability (MSI) of some MicroSatellites (MS) located in multiple critical regions of chromosome 3 were reported in L132 cells from Dunkerque City's PM 2 .5-exposed mono- or cocultures. (author)

  5. Separation and preconcentration of riboflavin from human plasma using polythionine coated magnetite/hydroxyapatite nanocomposite prior to analysis by surfactant-enhanced fluorimetry

    Science.gov (United States)

    Farzin, Leila; Shamsipur, Mojtaba

    2017-09-01

    The exploration of novel adsorption properties of conductive polymers based on hybridization with biocompatible nanomaterials receives an increasing interest. In this regard, hydroxyapatite (HA) bioceramic is of critical importance mainly owing to its facile synthesis, high surface area, economic and low toxicity in biological environments. In this work, we first prepared and characterized a magnetite/hydroxyapatite (Fe3O4/HA) nanocomposite using the bio-waste chicken eggshell via an attractive green way that involved low cost and irrespective of toxicity. Then, polythionine as a novel class of conductive polymers was in situ coated on the synthesized magnetic bioceramic for the separation and preconcentration of riboflavin (vitamin B2) in human plasma before its fluorimetric determination. Considering the putative role of riboflavin in protecting against cancer and cardiovascular diseases, it is essential to evaluate this vitamin in biological fluids. The described method possesses a linear range of 0.75-262.5 μg L- 1 (R2 = 0.9985) and a detection limit of 0.20 μg L- 1 (signal-to-noise ratio of 3). The relative standard deviations (RSDs) for single-sorbent repeatability and sorbent-to-sorbent reproducibility were less than 4.0% and 7.6% (n = 5), respectively. The respective enrichment factor and extraction recovery of the method found to be 35.7 and 98.4%. The analytical performance of method for riboflavin was characterized by good consistency of the results with those obtained by the enzyme-linked immunosorbent assay (ELISA) conventional method (p-value of < 0.05). The optimized protocol intended for control determinations of riboflavin in human subjects and is addressed to clinical laboratories.

  6. Uptake and cytotoxicity of citrate-coated gold nanospheres: Comparative studies on human endothelial and epithelial cells

    Directory of Open Access Journals (Sweden)

    Freese Christian

    2012-07-01

    Full Text Available Abstract Background The use of gold nanoparticles (AuNPs for diagnostic applications and for drug and gene-delivery is currently under intensive investigation. For such applications, biocompatibility and the absence of cytotoxicity of AuNPs is essential. Although generally considered as highly biocompatible, previous in vitro studies have shown that cytotoxicity of AuNPs in certain human epithelial cells was observed. In particular, the degree of purification of AuNPs (presence of sodium citrate residues on the particles was shown to affect the proliferation and induce cytotoxicity in these cells. To expand these studies, we have examined if the effects are related to nanoparticle size (10, 11 nm, 25 nm, to the presence of sodium citrate on the particles' surface or they are due to a varying degree of internalization of the AuNPs. Since two cell types are present in the major barriers to the outside in the human body, we have also included endothelial cells from the vasculature and blood brain barrier. Results Transmission electron microscopy demonstrates that the internalized gold nanoparticles are located within vesicles. Increased cytotoxicity was observed after exposure to AuNPs and was found to be concentration-dependent. In addition, cell viability and the proliferation of both endothelial cells decreased after exposure to gold nanoparticles, especially at high concentrations. Moreover, in contrast to the size of the particles (10 nm, 11 nm, 25 nm, the presence of sodium citrate on the nanoparticle surface appeared to enhance these effects. The effects on microvascular endothelial cells from blood vessels were slightly enhanced compared to the effects on brain-derived endothelial cells. A quantification of AuNPs within cells by ICP-AES showed that epithelial cells internalized a higher quantity of AuNPs compared to endothelial cells and that the quantity of uptake is not correlated with the amount of sodium citrate on the

  7. Survival in vivo of platelets stored for 48 hours in the buffycoat at 4 degrees C compared to platelet rich plasma stored at 22 degrees C

    NARCIS (Netherlands)

    Pietersz, R. N.; Loos, J. A.; Reesink, H. W.

    1987-01-01

    High speed centrifugation allows separation of whole blood into cell free plasma, a buffy coat and leukocyte poor red cells. The buffy coat can be used for the preparation of platelet concentrates. High lactate production at 22 degrees C requires storage of the buffy coat at 4 degrees C. Survival in

  8. Transmission of human immunodeficiency virus Type-1 by fresh-frozen plasma treated with methylene blue and light.

    Science.gov (United States)

    Álvarez, Manuel; Luis-Hidalgo, Mar; Bracho, María Alma; Blanquer, Amando; Larrea, Luis; Villalba, José; Puig, Nieves; Planelles, Dolores; Montoro, José; González-Candelas, Fernando; Roig, Roberto

    2016-04-01

    The risk of transfusion-transmitted infection (TTI) has been minimized by introduction of nucleic acid testing (NAT) and pathogen inactivation (PI). This case report describes transmission of human immunodeficiency virus Type 1 (HIV-1) to two recipients despite these measures. In March 2009 a possible TTI of HIV-1 was identified in a patient that had received pooled buffy coat platelet concentrate (BC-PLT) in November 2005. The subsequent lookback study found two more patients who had received methylene blue (MB)-treated fresh-frozen plasma (FFP) and red blood cells (RBCs) from the same donation. In November 2005 the donor had tested negative for both HIV antibodies and HIV-1 RNA by 44 minipool (44 MP) NAT. Repository samples of this donation and samples from the recipients were used for viral load (VL) and sequence analysis. HIV-1 RNA was detectable by individual donation (ID)-NAT in the repository sample from the 2005 window period donation and a VL of 135 copies/mL was measured. HIV-1 infection was confirmed in both recipients of both BC-PLT (65 mL of plasma) and MB-FFP (261 mL of plasma), but not in the patient that had received 4-week-old RBCs (20 mL of plasma). The sequence analysis revealed a close phylogenetic relationship between the virus strains isolated from the donor and recipients, compatible with TTI. Approximately 17,600 and 4400 virions in the MB-FFP and BC-PLT were infectious, but 1350 virions in the RBCs were not. ID-NAT would have prevented this transmission, but the combination of MP-NAT and MB-PI did not. © 2015 AABB.

  9. Human platelet lysate is a successful alternative serum supplement for propagation of monocyte-derived dendritic cells.

    Science.gov (United States)

    Švajger, Urban

    2017-04-01

    Clinical protocols for dendritic cell (DC) generation from monocytes require the use of animal serum-free supplements. Serum-free media can also require up to 1% of serum supplementation. In addition, recommendations based on the 3Rs (Refinement, Reduction, Replacement) principle also recommend the use of non-animal sera in in vitro studies. The aim of this study was to explore the potential use of platelet lysate (PL) for generation of optimally differentiated DCs from monocytes. Cells were isolated from buffy coats from healthy volunteers using immunomagnetic selection. DCs were differentiated in RPMI1640 supplemented with either 10% fetal bovine serum (FBS), 10% AB serum or 10% PL with the addition of granulocyte monocyte colony stimulating factor and interleukin-4. Generated DCs were assessed for their morphology, viability, endocytotic capacity, surface phenotype (immature, mature and tolerogenic DCs) and activation of important signaling pathways. DC function was evaluated on the basis of their allostimulatory capacity, cytokine profile and ability to induce different T-helper subsets. DCs generated with PL displayed normal viability, morphology and endocytotic capacity. Their differentiation and maturation phenotype was comparable to FBS-cultured DCs. They showed functional plasticity and up-regulated tolerogenic markers in response to their environment. PL-cultured mature DCs displayed unhindered allostimulatory potential and the capacity to induce Th1 responses. The use of PL allowed for activation of crucial signaling proteins associated with DC differentiation and maturation. This study demonstrates for the first time that human PL represents a successful alternative to FBS in differentiation of DCs from monocytes. DCs display the major phenotypic and functional characteristics compared with existing culture protocols. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  10. Comparison of human platelet lysate alternatives using expired and freshly isolated platelet concentrates for adipose-derived stromal cell expansion.

    Science.gov (United States)

    Dessels, Carla; Durandt, Chrisna; Pepper, Michael S

    2018-03-19

    Pooled human platelet lysate (pHPL) has been used to expand adipose-derived stromal cells (ASCs) and can be formulated using fresh or expired buffy coats (BCs) which are then resuspended in either plasma or an additive solution. Not much is known about the effects that expired products and additive solutions have on ASC expansion, and the need for quality control and release criteria has been expressed. This pilot study compared proliferation, cell size, morphology and immunophenotype of ASCs expanded in the different pHPL alternatives versus foetal bovine serum (FBS). Quality control criteria were assessed prior to and during the manufacture of the pHPL alternatives. ASCs were then expanded in 1%, 2.5%, 5% or 10% of the different pHPL alternatives or in 10% FBS. Cell size, morphology, cell number and immunophenotype were measured using microscopy and flow cytometry. The majority of the pHPL alternatives were within the recommended ranges for the quality control criteria. ASCs expanded in the pHPL alternatives were smaller in size, displayed a tighter spindle-shaped morphology, increased cell growth and had a similar immunophenotype (with the exception of CD34 and CD36) when compared to ASCs expanded in FBS. Here we report on the effects that expired BC products and additive solutions have on ASC expansion. When taken together, our findings indicate that all of the pHPL alternatives can be considered to be suitable replacements for FBS for ASC expansion, and that expired BC products can be used as an alternative to fresh BC products.

  11. Cellular interactions of lauric acid and dextran-coated magnetite nanoparticles

    International Nuclear Information System (INIS)

    Pradhan, Pallab; Giri, Jyotsnendu; Banerjee, Rinti; Bellare, Jayesh; Bahadur, Dhirendra

    2007-01-01

    In vitro cytocompatibility and cellular interactions of lauric acid and dextran-coated magnetite nanoparticles were evaluated with two different cell lines (mouse fibroblast and human cervical carcinoma). Lauric acid-coated magnetite nanoparticles were less cytocompatible than dextran-coated magnetite nanoparticles and cellular uptake of lauric acid-coated magnetic nanoparticles was more than that of dextran-coated magnetite nanoparticles. Lesser cytocompatibility and higher uptake of lauric acid-coated magnetite nanoparticles as compared to dextran-coated magnetic nanoparticles may be due to different cellular interactions by coating material. Thus, coating plays an important role in modulation of biocompatibility and cellular interaction of magnetic nanoparticles

  12. Adhesion profile and differentiation capacity of human adipose tissue derived mesenchymal stem cells grown on metal ion (Zn, Ag and Cu) doped hydroxyapatite nano-coated surfaces.

    Science.gov (United States)

    Bostancioglu, R Beklem; Gurbuz, Mevlut; Akyurekli, Ayse Gul; Dogan, Aydin; Koparal, A Savas; Koparal, A Tansu

    2017-07-01

    Accelerated Mesenchymal Stem Cells (MSCs) condensation and robust MSC-matrix and MSC-MSC interactions on nano-surfaces may provide critical factors contributing to such events, likely through the orchestrated signal cascades and cellular events modulated by the extracellular matrix. In this study, human adipose tissue derived mesenchymal stem cells (hMSC)', were grown on metal ion (Zn, Ag and Cu) doped hydroxyapatite (HAP) nano-coated surfaces. These metal ions are known to have different chemical and surface properties; therefore we investigated their respective contributions to cell viability, cellular behavior, osteogenic differentiation capacity and substrate-cell interaction. Nano-powders were produced using a wet chemical process. Air spray deposition was used to accumulate the metal ion doped HAP films on a glass substrate. Cell viability was determined by MTT, LDH and DNA quantitation methods Osteogenic differentiation capacity of hMSCs was analyzed with Alizarin Red Staining and Alkaline Phosphatase Specific Activity. Adhesion of the hMSCs and the effect of cell adhesion on biomaterial biocompatibility were explored through cell adhesion assay, immunofluorescence staining for vinculin and f-actin cytoskeleton components, SEM and microarray including 84 known extracellular matrix proteins and cell adhesion pathway genes, since, adhesion is the first step for good biocompability. The results demonstrate that the viability and osteogenic differentiation of the hMSCs (in growth media without osteogenic stimulation) and cell adhesion capability are higher on nanocoated surfaces that include Zn, Ag and/or Cu metal ions than commercial HAP. These results reveal that Zn, Ag and Cu metal ions contribute to the biocompatibility of exogenous material. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. A Human Amnion-Derived Extracellular Matrix-Coated Cell-Free Scaffold for Cartilage Repair: In Vitro and In Vivo Studies.

    Science.gov (United States)

    Nogami, Makiko; Kimura, Tomoatsu; Seki, Shoji; Matsui, Yoshito; Yoshida, Toshiko; Koike-Soko, Chika; Okabe, Motonori; Motomura, Hiraku; Gejo, Ryuichi; Nikaido, Toshio

    2016-04-01

    Extracellular matrix (ECM) derived from human amniotic mesenchymal cells (HAMs) has various biological activities. In this study, we developed a novel HAM-derived ECM-coated polylactic-co-glycolic acid (ECM-PLGA) scaffold, examined its property on mesenchymal cells, and investigated its potential as a cell-free scaffold for cartilage repair. ECM-PLGA scaffolds were developed by inoculating HAM on a PLGA. After decellularization by irradiation, accumulated ECM was examined. Exogenous cell growth and differentiation of rat mesenchymal stem cells (MSCs) on the ECM-PLGA were analyzed in vitro by cell attachment/proliferation assay and reverse transcription-polymerase chain reaction. The cell-free ECM-PLGA scaffolds were implanted into osteochondral defects in the trochlear groove of rat knees. After 4, 12, or 24 weeks, the animals were sacrificed and the harvested tissues were examined histologically. The ECM-PLGA contained ECM that mimicked natural amniotic stroma that contains type I collagen, fibronectin, hyaluronic acid, and chondroitin sulfates. The ECM-PLGA showed excellent properties of cell attachment and proliferation. MSCs inoculated on the ECM-PLGA scaffold showed accelerated type II collagen mRNA expression after 3 weeks in culture. The ECM-PLGA implanted into an osteochondral defect in rat knees induced gradual tissue regeneration and resulted in hyaline cartilage repair, which was better than that in the empty control group. These in vitro and in vivo experiments show that the cell-free scaffold composed of HAM-derived ECM and PLGA provides a favorable growth environment for MSCs and facilitates the cartilage repair process. The ECM-PLGA may become a "ready-made" biomaterial for cartilage repair therapy.

  14. Coating materials

    International Nuclear Information System (INIS)

    Ozeki, Takao; Kimura, Tadashi; Kobayashi, Juichi; Maeda, Yutaka; Nakamoto, Hideo.

    1969-01-01

    A non-solvent type coating material composition having properties as good as thermosetting acrylic or amino alkid resins is provided by employing active energy irradiation, particularly electron beams, using a radically polymerizable low molecular compound (A) (hereafter called an oligomer) containing at least two vinyl radicals in one molecule. This oligomer is produced by reacting an epoxy-containing vinyl monomer with alpha-, beta-ethylene unsaturated carboxylic acids or their anhydrides. The composition (I) contains 10% - 100% of this oligomer. In embodiments, an oligomer having a fiberous trivinyl construction is produced by reacting 180 parts by weight of glycidyl methacrylate ester with 130 parts of itaconic acid in the presence of a polymerization-inhibitor and an addition reaction catalyst at 90 0 C for 6 hours. In practice, the coating material compositions (1), consist of the whole oligomer [I-1]; (2), consist of 10-90% of (A) component and 90%-10% of vinyl monomers containing at least 30% (meth) acrylic monomer [I-2]; (3), 10%-90% of component (A) and 90%-10% of other monomers containing at least two vinyl radicals [I-3]; (4), a mixture of (I-2) and (I-3), [I-4]; and (5), consist of 50% or less unsaturated polyester of 500-5,000 molecular weight range or drying oil, or alkyd resin of 500-5,000 molecular weight range modified by drying oil, [I-5]. As a catalyst a tertiary amino vinyl compound is preferred. Five examples are given. (Iwakiri, K.)

  15. Coatings and Corrosion Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose: The mission of the Coatings and Corrosion Laboratory is to develop and analyze the effectiveness of innovative coatings test procedures while evaluating the...

  16. Graphene Coatings

    DEFF Research Database (Denmark)

    Stoot, Adam Carsten; Camilli, Luca; Bøggild, Peter

    2014-01-01

    Owing to its remarkable electrical and mechanical properties, graphene has been attracting tremendous interest in materials science. In particular, its chemical stability and impermeability make it a promising protective membrane. However, recent investigations reveal that single layer graphene...... cannot be used as a barrier in the long run, due to galvanic corrosion phenomena arising when oxygen or water penetrate through graphene cracks or domain boundaries. Here, we overcome this issue by using a multilayered (ML) graphene coating. Our lab- as well as industrial-scale tests demonstrate that ML...... graphene can effectively protect Ni in harsh environments, even after long term exposure. This is made possible by the presence of a high number of graphene layers, which can efficiently mask the cracks and domain boundaries defects found in individual layers of graphene. Our findings thus show...

  17. Coating materials

    International Nuclear Information System (INIS)

    Ozeki, Takao; Kimura, Tadashi; Kobayashi, Juichi; Maeda, Yutaka; Nakamoto, Hideo.

    1969-01-01

    A non-solvent type coating material composition is provided which can be hardened by irradiation with active energy, particularly electron beams, using a composition which contains 10%-100% of a radically polymerizable low molecular compound (A), (hereafter called an oligomer), having at least two vinyl radicals in one molecule. These compositions have a high degree of polymerization and characteristics equivalent to thermosetting acrylic or amino alkyd resin. The oligomer (A) is produced by reacting an epoxy-containing vinyl monomer with saturated polycarboxylic acids or anhydrides. In one embodiment, 146 parts by weight of adipic acid and 280 parts of glycidyl methacrylate ester undergo addition reaction in the presence of a polymerization-inhibitor and a catalyst at 90 0 C for 6 hours to produce an oligomer having a fiberous divinyl construction. The coating composition utilizes this oligomer in the forms of (I-1), a whole oligomer; (I-2), 0%-90% of this oligomer and 90%-10% of a vinyl monomer containing at least 30% of (meth) acrylic monomer; (I-3), 10%-90% of such oligomer and 90%-10% of other monomers containing at least two vinyl radicals in one molecule; (I-4), a mixture of (I-2) and (I-3) in proportion of 1/9 to 9/1, and (I-5), above four compositions each containing 50% or less unsaturated polyester or drying oil having 500-5,000 molecules or a drying oil-modified alkyd resin having 500-5,000 molecules. Four examples are given. (Iwakiri, K.)

  18. Electrocurtain coating process for coating solar mirrors

    Science.gov (United States)

    Kabagambe, Benjamin; Boyd, Donald W.; Buchanan, Michael J.; Kelly, Patrick; Kutilek, Luke A.; McCamy, James W.; McPheron, Douglas A.; Orosz, Gary R.; Limbacher, Raymond D.

    2013-10-15

    An electrically conductive protective coating or film is provided over the surface of a reflective coating of a solar mirror by flowing or directing a cation containing liquid and an anion containing liquid onto the conductive surface. The cation and the anion containing liquids are spaced from, and preferably out of contact with one another on the surface of the reflective coating as an electric current is moved through the anion containing liquid, the conductive surface between the liquids and the cation containing liquid to coat the conductive surface with the electrically conductive coating.

  19. A prospective, randomized pilot study on the safety and efficacy of recombinant human growth and differentiation factor-5 coated onto β-tricalcium phosphate for sinus lift augmentation.

    Science.gov (United States)

    Koch, Felix P; Becker, Jürgen; Terheyden, Hendrik; Capsius, Björn; Wagner, Wilfried

    2010-11-01

    The aim of this prospective, randomized clinical trial was to investigate the potential of recombinant human growth and differentiation factor-5 (rhGDF-5) coated onto β-tricalcium phosphate (β-TCP) (rhGDF-5/β-TCP) to support bone formation after sinus lift augmentation. In total, 31 patients participated in this multicenter clinical trial. They required a two-stage unilateral maxillary sinus floor augmentation (residual bone height augmentation with rhGDF-5/β-TCP and a 3-month healing period, (b) augmentation with rhGDF-5/β-TCP and a 4-month healing period and (c) medical device β-TCP mixed with autologous bone and a 4-month healing period. The primary study objective was the area of newly formed bone within the augmented area as assessed by histomorphometric evaluation of trephine bur biopsies. The osseous regeneration was similar in each treatment group; the amount of newly formed bone ranged between 28% (± 15.5%) and 31.8% (± 17.9%). Detailed analysis of histological data will be published elsewhere. As secondary efficacy variables, the augmentation height at the surgery site was measured by radiography. The largest augmentation was radiologically achieved in the rhGDF-5/β-TCP - 3-month and the rhGDF-5/β-TCP - 4-month treatment groups. As safety parameters, adverse events were recorded and anti-drug antibody levels were evaluated. Most of the adverse events were judged as unrelated to the study medication. Four out of 47 (8.5%) implants failed in patients treated with rhGDF-5/β-TCP, a result that is in agreement with the general implant failure rate of 5-15%. Transiently very low amounts of anti-rhGDF-5 antibodies were detected in some patients who received rhGDF-5, which was not related to the bone formation outcome. rhGDF-5/β-TCP was found to be effective and safe as the control treatment with autologous bone mixed β-TCP in sinus floor augmentation. Thus, further investigation regarding efficacy and safety will be carried out in larger patient

  20. Low Temperature Powder Coating

    Science.gov (United States)

    2011-02-09

    of volatile organic compounds (VOCs) and hazardous air pollutants (HAPs) • Legacy primers contain hexavalent chrome • Conventional powder coatings...coatings both in laboratory and field service evaluations • LTCPC allows environmental cost reductions through VOC/HAP elimination and hexavalent ... chrome reduction. • The LTCPC process greatly shortens the coating operation (LTCPC cures much more rapidly then conventional wet coatings) resulting in

  1. Analysis of the dose-response relationships of chromosomal aberrations after irradiation and bleomycin exposure of different human lymphocyte fractions in vitro

    International Nuclear Information System (INIS)

    Dresp, J.

    1979-01-01

    Cytogenetic analyses could be carried out on whole blood and pure T-cell cultures and also on cells of the 'buffy-coat'. In pure B-cell cultures even after 96 hours no mitogenic stimulation could be achieved. Parameters of radiosensitivity and bleomycin sensitivity were dicentric chromosomes, for which the dose-response relationships were calculated. Chromosomal investigations on the 'buffy-coat' cells did not provide indications referring to a varying radiosensitivity compared to whole blood cultures. In pure T-cell cultures T-lymphocytes, which had been separated after whole blood irradiation exposure, showed lower aberration rates than lymphocytes, which had been cultured after whole blood irradiation without previous separation. In the case of bleomycin exposure the treatment of previously separated leucocytes and T-lymphocytes respectively, led to lower aberration rates than the treatment before separation. Therefore it is apparently not necessary for a cytogenetic dosimetry or mutagenicity to depart from the whole blood culture method. (orig./MG) [de

  2. E-selectin is a viable route of infection for polymer-coated adenovirus retargeting in TNF-.alpha.-activated human umbilical vein endothelial cells

    Czech Academy of Sciences Publication Activity Database

    Bachtarzi, H.; Stevenson, M.; Šubr, Vladimír; Seymour, L. W.; Fisher, K. D.

    2011-01-01

    Roč. 19, č. 8 (2011), s. 690-700 ISSN 1061-186X Institutional research plan: CEZ:AV0Z40500505 Keywords : polymer-coated virus * vascular targeting * inflammation Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.696, year: 2011

  3. Flow coating apparatus and method of coating

    Science.gov (United States)

    Hanumanthu, Ramasubrahmaniam; Neyman, Patrick; MacDonald, Niles; Brophy, Brenor; Kopczynski, Kevin; Nair, Wood

    2014-03-11

    Disclosed is a flow coating apparatus, comprising a slot that can dispense a coating material in an approximately uniform manner along a distribution blade that increases uniformity by means of surface tension and transfers the uniform flow of coating material onto an inclined substrate such as for example glass, solar panels, windows or part of an electronic display. Also disclosed is a method of flow coating a substrate using the apparatus such that the substrate is positioned correctly relative to the distribution blade, a pre-wetting step is completed where both the blade and substrate are completed wetted with a pre-wet solution prior to dispensing of the coating material onto the distribution blade from the slot and hence onto the substrate. Thereafter the substrate is removed from the distribution blade and allowed to dry, thereby forming a coating.

  4. Investigation of metallurgical coatings for automotive applications

    Science.gov (United States)

    Su, Jun Feng

    Metallurgical coatings have been widely used in the automotive industry from component machining, engine daily running to body decoration due to their high hardness, wear resistance, corrosion resistance and low friction coefficient. With high demands in energy saving, weight reduction and limiting environmental impact, the use of new materials such as light Aluminum/magnesium alloys with high strength-weight ratio for engine block and advanced high-strength steel (AHSS) with better performance in crash energy management for die stamping, are increasing. However, challenges are emerging when these new materials are applied such as the wear of the relative soft light alloys and machining tools for hard AHSS. The protective metallurgical coatings are the best option to profit from these new materials' advantages without altering largely in mass production equipments, machinery, tools and human labor. In this dissertation, a plasma electrolytic oxidation (PEO) coating processing on aluminum alloys was introduced in engine cylinder bores to resist wear and corrosion. The tribological behavior of the PEO coatings under boundary and starve lubrication conditions was studied experimentally and numerically for the first time. Experimental results of the PEO coating demonstrated prominent wear resistance and low friction, taking into account the extreme working conditions. The numerical elastohydrodynamic lubrication (EHL) and asperity contact based tribological study also showed a promising approach on designing low friction and high wear resistant PEO coatings. Other than the fabrication of the new coatings, a novel coating evaluation methodology, namely, inclined impact sliding tester was presented in the second part of this dissertation. This methodology has been developed and applied in testing and analyzing physical vapor deposition (PVD)/ chemical vapor deposition (CVD)/PEO coatings. Failure mechanisms of these common metallurgical hard coatings were systematically

  5. European coatings conference - Marine coatings. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    This volume contains 13 lectures (manuscripts or powerpoint foils) with the following topics: 1. Impact of containerization on polyurethane and polyurea in marine and protective coatings (Malte Homann); 2. The application of combinatorial/high-throughput methods to the development of marine coatings (Bret Chisholm); 3. Progress and perspectives in the AMBIO (advanced nanostructured surfaces for the control of biofouling) Project (James Callow); 4. Release behaviour due to shear and pull-off of silicone coatings with a thickness gradient (James G. Kohl); 5. New liquid rheology additives for high build marine coatings (Andreas Freytag); 6. Effective corrosion protection with polyaniline, polpyrrole and polythiophene as anticorrosice additives for marine paints (Carlos Aleman); 7. Potential applications of sol gel technology for marine applications (Robert Akid); 8: Performance of biocide-free Antifouling Coatings for leisure boats (Bernd Daehne); 9. Novel biocidefree nanostructured antifouling coatings - can nano do the job? (Corne Rentrop); 10. One component high solids, VOC compliant high durability finish technology (Adrian Andrews); 11. High solid coatings - the hybrid solution (Luca Prezzi); 12. Unique organofunctional silicone resins for environmentally friendly high-performance coatings (Dieter Heldmann); 13. Silicone-alkyd paints for marine applications: from battleship-grey to green (Thomas Easton).

  6. PIT Coating Requirements Analysis

    International Nuclear Information System (INIS)

    MINTEER, D.J.

    2000-01-01

    This study identifies the applicable requirements for procurement and installation of a coating intended for tank farm valve and pump pit interior surfaces. These requirements are intended to be incorporated into project specification documents and design media. This study also evaluates previously recommended coatings and identifies requirement-compliant coating products

  7. PIT Coating Requirements Analysis

    Energy Technology Data Exchange (ETDEWEB)

    MINTEER, D.J.

    2000-10-20

    This study identifies the applicable requirements for procurement and installation of a coating intended for tank farm valve and pump pit interior surfaces. These requirements are intended to be incorporated into project specification documents and design media. This study also evaluates previously recommended coatings and identifies requirement-compliant coating products.

  8. Coatings for laser fusion

    International Nuclear Information System (INIS)

    Lowdermilk, W.H.

    1981-01-01

    Optical coatings are used in lasers systems for fusion research to control beam propagation and reduce surface reflection losses. The performance of coatings is important in the design, reliability, energy output, and cost of the laser systems. Significant developments in coating technology are required for future lasers for fusion research and eventual power reactors

  9. Fuel particle coating data

    International Nuclear Information System (INIS)

    Hollabaugh, C.M.; Wagner, P.; Wahman, L.A.; White, R.W.

    1977-01-01

    Development of coating on nuclear fuel particles for the High-Temperature Fuels Technology program at the Los Alamos Scientific Laboratory included process studies for low-density porous and high-density isotropic carbon coats, and for ZrC and ''alloy'' C/ZrC coats. This report documents the data generated by these studies

  10. 21 CFR 189.301 - Tin-coated lead foil capsules for wine bottles.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Tin-coated lead foil capsules for wine bottles. 189... SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES PROHIBITED FROM USE IN HUMAN FOOD... lead foil capsules for wine bottles. (a) Tin-coated lead foil is composed of a lead foil coated on one...

  11. Nanostructured glass–ceramic coatings for orthopaedic applications

    Science.gov (United States)

    Wang, Guocheng; Lu, Zufu; Liu, Xuanyong; Zhou, Xiaming; Ding, Chuanxian; Zreiqat, Hala

    2011-01-01

    Glass–ceramics have attracted much attention in the biomedical field, as they provide great possibilities to manipulate their properties by post-treatments, including strength, degradation rate and coefficient of thermal expansion. In this work, hardystonite (HT; Ca2ZnSi2O7) and sphene (SP; CaTiSiO5) glass–ceramic coatings with nanostructures were prepared by a plasma spray technique using conventional powders. The bonding strength and Vickers hardness for HT and SP coatings are higher than the reported values for plasma-sprayed hydroxyapatite coatings. Both types of coatings release bioactive calcium (Ca) and silicon (Si) ions into the surrounding environment. Mineralization test in cell-free culture medium showed that many mushroom-like Ca and phosphorus compounds formed on the HT coatings after 5 h, suggesting its high acellular mineralization ability. Primary human osteoblasts attach, spread and proliferate well on both types of coatings. Higher proliferation rate was observed on the HT coatings compared with the SP coatings and uncoated Ti-6Al-4V alloy, probably due to the zinc ions released from the HT coatings. Higher expression levels of Runx2, osteopontin and type I collagen were observed on both types of coatings compared with Ti-6Al-4V alloy, possibly due to the Ca and Si released from the coatings. Results of this study point to the potential use of HT and SP coatings for orthopaedic applications. PMID:21292725

  12. ATHENA optimized coating design

    DEFF Research Database (Denmark)

    Ferreira, Desiree Della Monica; Christensen, Finn Erland; Jakobsen, Anders Clemen

    2012-01-01

    The optimization of coating design for the ATHENA mission si described and the possibility of increasing the telescope effective area in the range between 0.1 and 10 keV is investigated. An independent computation of the on-axis effective area based on the mirror design of ATHENA is performed...... in order to review the current coating baseline. The performance of several material combinations, considering a simple bi-layer, simple multilayer and linear graded multilayer coatings are tested and simulation of the mirror performance considering both the optimized coating design and the coating...

  13. Metallic coating of microspheres

    International Nuclear Information System (INIS)

    Meyer, S.F.

    1980-01-01

    Extremely smooth, uniform metal coatings of micrometer thicknesses on microscopic glass spheres (microspheres) are often needed as targets for inertial confinement fusion (ICF) experiments. The first part of this paper reviews those methods used successfully to provide metal coated microspheres for ICF targets, including magnetron sputtering, electro- and electroless plating, and chemical vapor pyrolysis. The second part of this paper discusses some of the critical aspects of magnetron sputter coating of microspheres, including substrate requirements, the sticking of microspheres during coating (preventing a uniform coating), and the difficulties in growing the desired dense, smooth, uniform microstructure on continuously moving spherical substrates

  14. Antibacterial polymer coatings.

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Mollye C.; Allen, Ashley N.; Barnhart, Meghan; Tucker, Mark David; Hibbs, Michael R.

    2009-09-01

    A series of poly(sulfone)s with quaternary ammonium groups and another series with aldehyde groups are synthesized and tested for biocidal activity against vegetative bacteria and spores, respectively. The polymers are sprayed onto substrates as coatings which are then exposed to aqueous suspensions of organisms. The coatings are inherently biocidal and do not release any agents into the environment. The coatings adhere well to both glass and CARC-coated coupons and they exhibit significant biotoxicity. The most effective quaternary ammonium polymers kills 99.9% of both gram negative and gram positive bacteria and the best aldehyde coating kills 81% of the spores on its surface.

  15. Coated Aerogel Beads

    Science.gov (United States)

    Littman, Howard (Inventor); Plawsky, Joel L. (Inventor); Paccione, John D. (Inventor)

    2014-01-01

    Methods and apparatus for coating particulate material are provided. The apparatus includes a vessel having a top and a bottom, a vertically extending conduit having an inlet in the vessel and an outlet outside of the vessel, a first fluid inlet in the bottom of the vessel for introducing a transfer fluid, a second fluid inlet in the bottom of the vessel for introducing a coating fluid, and a fluid outlet from the vessel. The method includes steps of agitating a material, contacting the material with a coating material, and drying the coating material to produce a coated material. The invention may be adapted to coat aerogel beads, among other materials. A coated aerogel bead and an aerogel-based insulation material are also disclosed.

  16. Anticorrosive coatings: a review

    DEFF Research Database (Denmark)

    Sørensen, Per Aggerholm; Kiil, Søren; Dam-Johansen, Kim

    2009-01-01

    of volatile organic compounds (VOCs) have caused significant changes in the anticorrosive coating industry. The requirement for new VOC-compliant coating technologies means that coating manufacturers can no longer rely on the extensive track record of their time-served products to convince consumers...... of their suitability for use. An important aspect in the development of new VOC-compliant, high-performance anticorrosive coating systems is a thorough knowledge of the components in anticorrosive coatings, their interactions, their advantages and limitations, as well as a detailed knowledge on the failure modes......, and inhibitive coatings are outlined. In the past decades, several alternatives to organic solvent-borne coatings have reached the commercial market. This review also presents some of these technologies and discusses some of their advantages and limitations. Finally, some of the mechanisms leading to degradation...

  17. Pixelated coatings and advanced IR coatings

    Science.gov (United States)

    Pradal, Fabien; Portier, Benjamin; Oussalah, Meihdi; Leplan, Hervé

    2017-09-01

    Reosc developed pixelated infrared coatings on detector. Reosc manufactured thick pixelated multilayer stacks on IR-focal plane arrays for bi-spectral imaging systems, demonstrating high filter performance, low crosstalk, and no deterioration of the device sensitivities. More recently, a 5-pixel filter matrix was designed and fabricated. Recent developments in pixelated coatings, shows that high performance infrared filters can be coated directly on detector for multispectral imaging. Next generation space instrument can benefit from this technology to reduce their weight and consumptions.

  18. Bioelectric and Morphological Response of Liquid-Covered Human Airway Epithelial Calu-3 Cell Monolayer to Periodic Deposition of Colloidal 3-Mercaptopropionic-Acid Coated CdSe-CdS/ZnS Core-Multishell Quantum Dots.

    Directory of Open Access Journals (Sweden)

    Aizat Turdalieva

    Full Text Available Lung epithelial cells are extensively exposed to nanoparticles present in the modern urban environment. Nanoparticles, including colloidal quantum dots (QDs, are also considered to be potentially useful carriers for the delivery of drugs into the body. It is therefore important to understand the ways of distribution and the effects of the various types of nanoparticles in the lung epithelium. We use a model system of liquid-covered human airway epithelial Calu-3 cell cultures to study the immediate and long-term effects of repeated deposition of colloidal 3-mercaptopropionic-acid coated CdSe-CdS/ZnS core-multishell QDs on the lung epithelial cell surface. By live confocal microscope imaging and by QD fluorescence measurements we show that the QD permeation through the mature epithelial monolayers is very limited. At the time of QD deposition, the transepithelial electrical resistance (TEER of the epithelial monolayers transiently decreased, with the decrement being proportional to the QD dose. Repeated QD deposition, once every six days for two months, lead to accumulation of only small amounts of the QDs in the cell monolayer. However, it did not induce any noticeable changes in the long-term TEER and the molecular morphology of the cells. The colloidal 3-mercaptopropionic-acid coated CdSe-CdS/ZnS core-multishell QDs could therefore be potentially used for the delivery of drugs intended for the surface of the lung epithelia during limited treatment periods.

  19. Combustion chemical vapor desposited coatings for thermal barrier coating systems

    Energy Technology Data Exchange (ETDEWEB)

    Hampikian, J.M.; Carter, W.B. [Georgia Institute of Technology, Atlanta, GA (United States)

    1995-10-01

    The new deposition process, combustion chemical vapor deposition, shows a great deal of promise in the area of thermal barrier coating systems. This technique produces dense, adherent coatings, and does not require a reaction chamber. Coatings can therefore be applied in the open atmosphere. The process is potentially suitable for producing high quality CVD coatings for use as interlayers between the bond coat and thermal barrier coating, and/or as overlayers, on top of thermal barrier coatings.

  20. Assessing the proposed pre-last glacial maximum human occupation of North America at Coats-Hines-Litchy, Tennessee, and other sites

    Science.gov (United States)

    Tune, Jesse W.; Waters, Michael R.; Schmalle, Kayla A.; DeSantis, Larisa R. G.; Kamenov, George D.

    2018-04-01

    Genomic studies indicate that the first Pleistocene foragers who entered North America diverged from ancestral populations in Beringia sometime after the Last Glacial Maximum (LGM); however, several archaeological sites in North America have been proposed to predate the LGM. We present the results of our excavation and analysis of one such site, Coats-Hines-Litchy, Tennessee, which show that this site is a paleontological locality containing a geofact assemblage that pre-dates the LGM. Other sites in North America that purportedly predate the LGM occur in geomorphic contexts that are also conducive to the formation of geofact assemblages. As such, we propose that the reported artifacts from these sites were created by natural processes. No sites in North America currently provide credible evidence of a pre-LGM occupation.

  1. Quantitative Appearance Inspection for Film Coated Tablets.

    Science.gov (United States)

    Yoshino, Hiroyuki; Yamashita, Kazunari; Iwao, Yasunori; Noguchi, Shuji; Itai, Shigeru

    2016-01-01

    The decision criteria for the physical appearance of pharmaceutical products are subjective and qualitative means of evaluation that are based entirely on human interpretation. In this study, we have developed a comprehensive method for the quantitative analysis of the physical appearance of film coated tablets. Three different kinds of film coated tablets with considerable differences in their physical appearances were manufactured as models, and their surface roughness, contact angle, color measurements and physicochemical properties were investigated as potential characteristics for the quantitative analysis of their physical appearance. All of these characteristics were useful for the quantitative evaluation of the physical appearances of the tablets, and could potentially be used to establish decision criteria to assess the quality of tablets. In particular, the analysis of the surface roughness and film coating properties of the tablets by terahertz spectroscopy allowed for an effective evaluation of the tablets' properties. These results indicated the possibility of inspecting the appearance of tablets during the film coating process.

  2. Preliminary coating design and coating developments for ATHENA

    DEFF Research Database (Denmark)

    Jakobsen, Anders Clemen; Ferreira, Desiree Della Monica; Christensen, Finn Erland

    2011-01-01

    We present initial novel coating design for ATHENA. We make use of both simple bilayer coatings of Ir and B4C and more complex constant period multilayer coatings to enhance the effective area and cover the energy range from 0.1 to 10 keV. We also present the coating technology used...... for these designs and present test results from coatings....

  3. Plasma sprayed thermoregulating coatings

    International Nuclear Information System (INIS)

    Kudinov, V.V.; Puzanov, A.A.; Zambrzhitskij, A.P.; Soboleva, V.V.

    1979-01-01

    Shown is the possibility of plasma spraying application for thermoregulating coating formation. Given are test results of service properties of BeO, Al 2 O 2 plasma coatings on the substrates of the MA2-1 magnesium alloy. Described is a device for studying durability of coating optical parameters under ultraviolet irradiation in deep vacuum. Dynamics of absorption coefficient, growth caused by an increase in absorption centers amount under such irradiation is investigated

  4. Zinc phosphate conversion coatings

    Science.gov (United States)

    Sugama, Toshifumi

    1997-01-01

    Zinc phosphate conversion coatings for producing metals which exhibit enhanced corrosion prevention characteristics are prepared by the addition of a transition-metal-compound promoter comprising a manganese, iron, cobalt, nickel, or copper compound and an electrolyte such as polyacrylic acid, polymethacrylic acid, polyitaconic acid and poly-L-glutamic acid to a phosphating solution. These coatings are further improved by the incorporation of Fe ions. Thermal treatment of zinc phosphate coatings to generate .alpha.-phase anhydrous zinc phosphate improves the corrosion prevention qualities of the resulting coated metal.

  5. Silica coatings on clarithromycin.

    Science.gov (United States)

    Bele, Marjan; Dmitrasinovic, Dorde; Planinsek, Odon; Salobir, Mateja; Srcic, Stane; Gaberscek, Miran; Jamnik, Janko

    2005-03-03

    Pre-crystallized clarithromycin (6-O-methylerythromycin A) particles were coated with silica from the tetraethyl orthosilicate (TEOS)-ethanol-aqueous ammonia system. The coatings had a typical thickness of 100-150 nm and presented about 15 wt.% of the silica-drug composite material. The properties of the coatings depended on reactant concentration, temperature and mixing rate and, in particular, on the presence of a cationic surfactant (cetylpyridinium chloride). In the presence of cetylpyridinium chloride the silica coatings slightly decreased the rate of pure clarithromycin dissolution.

  6. A New Method to Develop Human Dental Pulp Cells and Platelet-rich Fibrin Complex.

    Science.gov (United States)

    He, Xuan; Chen, Wen-Xia; Ban, Guifei; Wei, Wei; Zhou, Jun; Chen, Wen-Jin; Li, Xian-Yu

    2016-11-01

    Platelet-rich fibrin (PRF) has been used as a scaffold material in various tissue regeneration studies. In the previous methods to combine seed cells with PRF, the structure of PRF was damaged, and the manipulation time in vitro was also increased. The objective of this in vitro study was to explore an appropriate method to develop a PRF-human dental pulp cell (hDPC) complex to maintain PRF structure integrity and to find out the most efficient part of PRF. The PRF-hDPC complex was developed at 3 different time points during PRF preparation: (1) the before centrifugation (BC) group, the hDPC suspension was added to the venous blood before blood centrifugation; (2) the immediately after centrifugation (IAC) group, the hDPC suspension was added immediately after blood centrifugation; (3) the after centrifugation (AC) group, the hDPC suspension was added 10 minutes after blood centrifugation; and (4) the control group, PRF without hDPC suspension. The prepared PRF-hDPC complexes were cultured for 7 days. The samples were fixed for histologic, immunohistochemistry, and scanning electron microscopic evaluation. Real-time polymerase chain reaction was performed to evaluate messenger RNA expression of alkaline phosphatase and dentin sialophosphoprotein. Enzyme-linked immunosorbent assay quantification for growth factors was performed within the different parts of the PRF. Histologic, immunohistochemistry, and scanning electron microscopic results revealed that hDPCs were only found in the BC group and exhibited favorable proliferation. Real-time polymerase chain reaction revealed that alkaline phosphatase and dentin sialophosphoprotein expression increased in the cultured PRF-hDPC complex. The lower part of the PRF released the maximum quantity of growth factors. Our new method to develop a PRF-hDPCs complex maintained PRF structure integrity. The hDPCs were distributed in the buffy coat, which might be the most efficient part of PRF. Copyright © 2016 American

  7. Research Advances. Image Pinpoints All 5 Million Atoms in Viral Coat; Bilirubin, "Animals-Only" Pigment, Found in Plants; New Evidence Shows Humans Make Salicylic Acid

    Science.gov (United States)

    King, Angela G.

    2009-08-01

    Recent "firsts" in chemical research: image of a viral capsid pinpointing 5 million atoms; isolation and identification of an "animal" pigment, bilirubin, from a plant source; evidence that humans make salicylic acid.

  8. A simple and sensitive methodology for voltammetric determination of valproic acid in human blood plasma samples using 3-aminopropyletriethoxy silane coated magnetic nanoparticles modified pencil graphite electrode.

    Science.gov (United States)

    Zabardasti, Abedin; Afrouzi, Hossein; Talemi, Rasoul Pourtaghavi

    2017-07-01

    In this work, we have prepared a nano-material modified pencil graphite electrode for the sensing of valproic acid (VA) by immobilization 3-aminopropyletriethoxy silane coated magnetic nanoparticles (APTES-MNPs) on the pencil graphite surface (PGE). Electrochemical studies indicated that the APTES-MNPs efficiently increased the electron transfer kinetics between VA and the electrode and the free NH 2 groups of the APTES on the outer surface of magnetic nanoparticles can interact with carboxyl groups of VA. Based on this, we have proposed a sensitive, rapid and convenient electrochemical method for VA determination. Under the optimized conditions, the reduction peak current of VA is found to be proportional to its concentration in the range of 1.0 (±0.2) to 100.0 (±0.3) ppm with a detection limit of 0.4 (±0.1) ppm. The whole sensor fabrication process was characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) methods with using [Fe(CN) 6 ] 3-/4- as an electrochemical redox indicator. The prepared modified electrode showed several advantages such as high sensitivity, selectivity, ease of preparation and good repeatability, reproducibility and stability. The proposed method was applied to determination of valproic acid in blood plasma samples and the obtained results were satisfactory accurate. Copyright © 2017. Published by Elsevier B.V.

  9. Superhydrophobic silica coating by dip coating method

    International Nuclear Information System (INIS)

    Mahadik, Satish A.; Parale, Vinayak; Vhatkara, Rajiv S.; Mahadik, Dinesh B.; Kavale, Mahendra S.; Wagh, Pratap B.; Gupta, Satish; Gurav, Jyoti

    2013-01-01

    Herein, we report a simple and low cost method for the fabrication of superhydrophobic coating surface on quartz substrates via sol-gel dip coating method at room temperature. Desired surface chemistry and texture growth for superhydrophobicity developed under double step sol–gel process at room temperature. The resultant superhydrophobic surfaces were characterized by Field-emission scanning electron microscopy (FE-SEM), Atomic force microscopy (AFM), water contact angle (WCA) measurement, differential thermal gravimetric analysis-differential thermal analysis (TGA-DTA) calorimetry and optical spectrometer. Coating shows the ultra high water contact angle about 168 ± 2° and water sliding angle 3 ± 1° and superoleophilic with petroleum oils. This approach allows a simple strategy for the fabrication process of superhydrophilic–superhydrophobic on same surfaces with high thermal stability of superhydrophobicity up to 560 °C. Thus, durability, special wettability and thermal stability of superhydrophobicity expand their application fields.

  10. Isolation and characterization of gallic acid and methyl gallate from the seed coats of Givotia rottleriformis Griff. and their anti-proliferative effect on human epidermoid carcinoma A431 cells

    Directory of Open Access Journals (Sweden)

    Samuel Kamatham

    2015-01-01

    Full Text Available Gallic acid (GA and its derivative methyl gallate (MG are well studied plant phenolics. They have exhibited anticancer effects in several cancer cell lines. However, the presence of GA/MG in the seed coats of Givotia rottleriformis and their inhibitory effect on human epidermoid carcinoma (A431 skin cancer cells were not reported. In this study we have isolated and chemically characterized the bioactive compounds GA and MG from the bioassay guided methanolic (MeOH seed coat extracts of G. rottleriformis. The fractions obtained from open silica column chromatography were subjected to in vitro enzymatic assays. Among seven fractions we found that only fractions 5 and 6 showed significant inhibition activity toward COX-1 with an IC50 value of 28 μg/mL and 9.3 μg/mL and COX-2 with an IC50 value of 35 μg/mL and 7.0 μg/mL respectively. However, we could not find 5-LOX enzyme inhibition activity. MG (10 mg/g DW and GA (6 mg/g DW were the major compounds of seed coats. Cell viability was analyzed by 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide (MTT assay, which showed that GA/MG significantly reduced the growth of A431 cells with an IC50 value of 25 μg/mL and 53 μg/mL and 11 μg/mL and 43 μg/mL at 24 h and 48 h, respectively. However the cytotoxic effect of GA/MG on HaCaT normal skin keratinocyte cell line was found to be less. Western blot analysis has shown that GA/MG treatment down regulated Bcl-2 and up regulated cleaved caspase-3 with respect to increasing doses. Our results conclude that GA and MG have potential anticancer effects and can be used as therapeutic agents for skin cancers.

  11. Application of a lipid-coated hollow calcium phosphate nanoparticle in synergistic co-delivery of doxorubicin and paclitaxel for the treatment of human lung cancer A549 cells

    Directory of Open Access Journals (Sweden)

    Wu C

    2017-10-01

    Full Text Available Chao Wu, Jie Xu, Yanna Hao, Ying Zhao, Yang Qiu, Jie Jiang, Tong Yu, Peng Ji, Ying Liu Pharmacy School, Jinzhou Medical University, Jinzhou, China Abstract: In this study, we developed a lipid-coated hollow calcium phosphate (LCP nanoparticle for the combined application of two chemotherapeutic drugs to human lung cancer A549 cells. Hydrophilic doxorubicin (DOX was incorporated into the hollow structure of hollow calcium phosphate (HCP, and a lipid bilayer containing hydrophobic paclitaxel (PTX was subsequently coated on the surface of HCP. The study on combinational effects demonstrated that the combination of DOX and PTX at a mass ratio of 12:1 showed a synergistic effect against A549 cells. The particle size, zeta potential, and encapsulation efficiency were measured to obtain optimal values: particle size was 335.0 3.2 nm, zeta potential -41.1 mV, and encapsulation efficiency 80.40%±2.24%. An in vitro release study indicated that LCP produced a sustained drug release. A549 cells had a better uptake of LCP with good biocompatibility. Furthermore, in vitro cytotoxicity experiment, apoptosis analysis, in vivo anti-tumor efficacy and protein expression analysis of Bax, Bcl-2, and Caspase-3 demonstrated that the co-delivery system based on LCP had significant synergistic anti-tumor activity. All conclusions suggested that LCP is a promising platform for co-delivery of multiple anti-tumor drugs. Keywords: doxorubicin, paclitaxel, co-delivery, lipid, hollow calcium phosphate, lung cancer cell

  12. Coated electroactive materials

    Science.gov (United States)

    Amine, Khalil; Abouimrane, Ali

    2016-08-30

    A process includes suspending an electroactive material in a solvent, suspending or dissolving a carbon precursor in the solvent; and depositing the carbon precursor on the electroactive material to form a carbon-coated electroactive material. Compositions include a graphene-coated electroactive material prepared from a solution phase mixture or suspension of an electroactive material and graphene, graphene oxide, or a mixture thereof.

  13. Rock-hard coatings

    OpenAIRE

    Muller, M.

    2007-01-01

    Aircraft jet engines have to be able to withstand infernal conditions. Extreme heat and bitter cold tax coatings to the limit. Materials expert Dr Ir. Wim Sloof fits atoms together to develop rock-hard coatings. The latest invention in this field is known as ceramic matrix composites. Sloof has signed an agreement with a number of parties to investigate this material further.

  14. Metallurgical coating system

    International Nuclear Information System (INIS)

    Daniels, L.C.; Whittaker, G.S.

    1984-01-01

    The present invention relates to a novel metallurgical coating system which provides corrosion resistance and non-stick properties to metallic components which are subjected to unusually severe operating conditions. The coating system comprises a first layer comprising tantalum which is deposited upon a substrate and a second layer comprising molybdenum disilicide which is deposited upon the first layer

  15. Rock-hard coatings

    NARCIS (Netherlands)

    Muller, M.

    2007-01-01

    Aircraft jet engines have to be able to withstand infernal conditions. Extreme heat and bitter cold tax coatings to the limit. Materials expert Dr Ir. Wim Sloof fits atoms together to develop rock-hard coatings. The latest invention in this field is known as ceramic matrix composites. Sloof has

  16. Unobtrusive graphene coatings

    NARCIS (Netherlands)

    Mugele, Friedrich Gunther

    2012-01-01

    The contact angle of water drops on substrates for which the wettability is dominated by van der Waals forces remains unchanged when the substrates are coated with a monolayer of graphene. Such 'wetting transparency' could lead to superior conducting and hydrophobic graphene-coated surfaces with

  17. Coating thickness measurement

    International Nuclear Information System (INIS)

    1976-12-01

    The standard specifies measurements of the coating thickness, which make use of beta backscattering and/or x-ray fluorescence. For commonly used combinations of coating material and base material the appropriate measuring ranges and radionuclides to be used are given for continuous as well as for discontinuous measurements

  18. Duplex aluminized coatings

    Science.gov (United States)

    Gedwill, M. A.; Grisaffe, S. J. (Inventor)

    1975-01-01

    The surface of a metallic base system is initially coated with a metallic alloy layer that is ductile and oxidation resistant. An aluminide coating is then applied to the metallic alloy layer. The chemistry of the metallic alloy layer is such that the oxidation resistance of the subsequently aluminized outermost layer is not seriously degraded.

  19. Coated ceramic breeder materials

    Science.gov (United States)

    Tam, Shiu-Wing; Johnson, Carl E.

    1987-01-01

    A breeder material for use in a breeder blanket of a nuclear reactor is disclosed. The breeder material comprises a core material of lithium containing ceramic particles which has been coated with a neutron multiplier such as Be or BeO, which coating has a higher thermal conductivity than the core material.

  20. Antifungal Paper Based on a Polyborneolacrylate Coating

    Directory of Open Access Journals (Sweden)

    Jiangqi Xu

    2018-04-01

    Full Text Available Paper documents and products are very susceptible to microbial contamination and damage. Fungi are mainly responsible for those biodeterioration processes. Traditional microbicidal strategies constitute a serious health risk even when microbes are dead. Ideal methods should not be toxic to humans and should have no adverse effects on paper, but should own a broad spectrum, good chemical stability and low cost. In this work, we utilize an advanced antimicrobial strategy of surface stereochemistry by applying a coating of a shallow layer of polyborneolacrylate (PBA, resulting in the desired antifungal performance. The PBA-coated paper is challenged with the most common air-borne fungi growing on paper, Aspergillus niger and Penicillium sp. Ten percent by weight of the coating concentration or a 19-μm infiltration of PBA is sufficient to keep the paper spotless. The PBA coating also exhibits significant inhibition of spores’ germination. After PBA coating, both physicochemical properties (paper whiteness, pH, mechanical strength and inking performance display only slight changes, which are acceptable for general utilization. This PBA coating method is nontoxic, rapid and cost-effective, thus demonstrating great potential for applications in paper products.

  1. Radiation curable coating compositions

    International Nuclear Information System (INIS)

    Jenkinson, R.D.; Carder, C.H.

    1979-01-01

    The present invention provides a low-toxicity diluent component for radiation curable coating compositions that contain an acrylyl or methacryly oligomer or resin component such as an acrylyl urethane oligomer. The low-toxicity diluent component of this invention is chosen from the group consisting of tetraethlorthosilicate and tetraethoxyethylorthosilicate. When the diluent component is used as described, benefits in addition to viscosity reduction, may be realized. Application characteristics of the uncured coatings composition, such as flowability, leveling, and smoothness are notably improved. Upon curing by exposure to actinic radiation, the coating composition forms a solid, non-tacky surface free of pits, fissures or other irregularities. While there is no readily apparent reactive mechanism by which the orthosilicate becomes chemically bonded to the cured coating, the presence of silicon in the cured coating has been confirmed by scanning electron microscopy. 12 drawing

  2. Charged-particle coating

    International Nuclear Information System (INIS)

    Johnson, W.L.; Crane, J.K.; Hendricks, C.D.

    1980-01-01

    Advanced target designs require thicker (approx. 300 μm) coatings and better surface finishes that can be produced with current coating techniques. An advanced coating technique is proposed to provide maximum control of the coating flux and optimum manipulation of the shell during processing. In this scheme a small beam of ions or particles of known incident energy are collided with a levitated spherical mandrel. Precise control of the incident energy and angle of the deposition flux optimizes the control of the coating morphology while controlled rotation and noncontact support of the shell minimizes the possibility of particulate or damage generated defects. Almost infinite variability of the incident energy and material in this process provides increased flexibility of the target designs which can be physically realized

  3. Coating thickness measuring device

    International Nuclear Information System (INIS)

    Joffe, B.B.; Sawyer, B.E.; Spongr, J.J.

    1984-01-01

    A device especially adapted for measuring the thickness of coatings on small, complexly-shaped parts, such as, for example, electronic connectors, electronic contacts, or the like. The device includes a source of beta radiation and a radiation detector whereby backscatter of the radiation from the coated part can be detected and the thickness of the coating ascertained. The radiation source and detector are positioned in overlying relationship to the coated part and a microscope is provided to accurately position the device with respect to the part. Means are provided to control the rate of descent of the radiation source and radiation detector from its suspended position to its operating position and the resulting impact it makes with the coated part to thereby promote uniformity of readings from operator to operator, and also to avoid excessive impact with the part, thereby improving accuracy of measurement and eliminating damage to the parts

  4. Induction of Apoptosis in Human Cancer Cells Through Extrinsic and Intrinsic Pathways by Balanites aegyptiaca Furostanol Saponins and Saponin-Coated SilverNanoparticles.

    Science.gov (United States)

    Yassin, Abdelrahman M; El-Deeb, Nehal M; Metwaly, Ahmed M; El Fawal, Gomaa F; Radwan, Mohamed M; Hafez, Elsayed E

    2017-08-01

    The aim of this investigation is to examine the anticancer activities of Balanites aegyptiaca fruit extract with its biogenic silver nanoparticles (AgNPs) against colon and liver cancer cells. B. aegyptiaca aqueous extract was fractionated according to polarity and by biosynthesized AgNP. The cytotoxicity of the extract, semi-purified fractions, and the AgNPs was examined on noncancerous cell lines. The safer fraction was subjected to ultra-performance liquid chromatography-MS to identify the major active constituents. The anticancer activities of the nontoxic doses of all the used treatments were tested against HepG2 and CaCo2 cells. The nontoxic dose of the B. aegyptiaca (0.63 mg/ml) extract showed high anti-proliferative activities against HepG2 and CaCo2 with a percentage of 81 and 77%, respectively. The butanol fraction was safer than the other two fractions with 46.3 and 90.35% anti-proliferative activity against Caco2 and HepG2 cells, respectively. The nontoxic dose of AgNPs (0.63 mg/ml) inhibits both HepG2 and Caco2 cells with a percentage of 84.5 and 83.4%, respectively. In addition, AgNPs regulate the expression of certain genes with folding higher than that of crude extract. Saponin-coated AgNPs showed great abilities to select the most anticancer ingredient(s) from the B. aegyptiaca extract with a more safety pattern than the polarity gradient fractionation.

  5. Comparison of cellular effects of starch-coated SPIONs and poly(lactic-co-glycolic acid) matrix nanoparticles on human monocytes.

    Science.gov (United States)

    Gonnissen, Dominik; Qu, Ying; Langer, Klaus; Öztürk, Cengiz; Zhao, Yuliang; Chen, Chunying; Seebohm, Guiscard; Düfer, Martina; Fuchs, Harald; Galla, Hans-Joachim; Riehemann, Kristina

    Within the last years, progress has been made in the knowledge of the properties of medically used nanoparticles and their toxic effects, but still, little is known about their influence on cellular processes of immune cells. The aim of our comparative study was to present the influence of two different nanoparticle types on subcellular processes of primary monocytes and the leukemic monocyte cell line MM6. We used core-shell starch-coated superparamagnetic iron oxide nanoparticles (SPIONs) and matrix poly(lactic-co-glycolic acid) (PLGA) nanoparticles for our experiments. In addition to typical biocompatibility testing like the detection of necrosis or secretion of interleukins (ILs), we investigated the impact of these nanoparticles on the actin cytoskeleton and the two voltage-gated potassium channels Kv1.3 and Kv7.1. Induction of necrosis was not seen for PLGA nanoparticles and SPIONs in primary monocytes and MM6 cells. Likewise, no alteration in secretion of IL-1β and IL-10 was detected under the same experimental conditions. In contrast, IL-6 secretion was exclusively downregulated in primary monocytes after contact with both nanoparticles. Two-electrode voltage clamp experiments revealed that both nanoparticles reduce currents of the aforementioned potassium channels. The two nanoparticles differed significantly in their impact on the actin cytoskeleton, demonstrated via atomic force microscopy elasticity measurement and phalloidin staining. While SPIONs led to the disruption of the respective cytoskeleton, PLGA did not show any influence in both experimental setups. The difference in the effects on ion channels and the actin cytoskeleton suggests that nanoparticles affect these subcellular components via different pathways. Our data indicate that the alteration of the cytoskeleton and the effect on ion channels are new parameters that describe the influence of nanoparticles on cells. The results are highly relevant for medical application and further

  6. Female Longitudinal Anal Muscles or Conjoint Longitudinal Coats Extend into the Subcutaneous Tissue along the Vaginal Vestibule: A Histological Study Using Human Fetuses

    Science.gov (United States)

    Arakawa, Takashi; Abe, Hiroshi; Rodríguez-Vízquez, Jose Francisco; Murakami, Gen; Sugihara, Kenichi

    2013-01-01

    Purpose It is still unclear whether the longitudinal anal muscles or conjoint longitudinal coats (CLCs) are attached to the vagina, although such an attachment, if present, would appear to make an important contribution to the integrated supportive system of the female pelvic floor. Materials and Methods Using immunohistochemistry for smooth muscle actin, we examined semiserial frontal sections of 1) eleven female late-stage fetuses at 28-37 weeks of gestation, 2) two female middle-stage fetus (2 specimens at 13 weeks), and, 3) six male fetuses at 12 and 37 weeks as a comparison of the morphology. Results In late-stage female fetuses, the CLCs consistently (11/11) extended into the subcutaneous tissue along the vaginal vestibule on the anterior side of the external anal sphincter. Lateral to the CLCs, the external anal sphincter also extended anteriorly toward the vaginal side walls. The anterior part of the CLCs originated from the perimysium of the levator ani muscle without any contribution of the rectal longitudinal muscle layer. However, in 2 female middle-stage fetuses, smooth muscles along the vestibulum extended superiorly toward the levetor ani sling. In male fetuses, the CLCs were separated from another subcutaneous smooth muscle along the scrotal raphe (posterior parts of the dartos layer) by fatty tissue. Conclusion In terms of topographical anatomy, the female anterior CLCs are likely to correspond to the lateral extension of the perineal body (a bulky subcutaneous smooth muscle mass present in adult women), supporting the vaginal vestibule by transmission of force from the levator ani. PMID:23549829

  7. Neocellularization and neovascularization of nanosized bioactive glass-coated decellularized trabecular bone scaffolds

    KAUST Repository

    Gerhardt, Lutz Christian; Widdows, Kate L.; Erol, Melek M.; Nandakumar, Anandkumar; Roqan, Iman S.; Ansari, Tahera I.; Boccaccini, Aldo R.

    2012-01-01

    amount of vascular endothelial growth factor (VEGF) secreted by human fibroblasts grown on n-BG coatings (0-1.245 mg/cm 2), decellularized trabecular bone samples (porosity: 43-81%) were coated with n-BG particles. Grown on n-BG particles at a coating

  8. Expression of Human papillomavirus 16 E7ggg oncoprotein on N- and C-terminus of Potato virus X coat protein in bacterial and plant cells

    Czech Academy of Sciences Publication Activity Database

    Plchová, Helena; Moravec, Tomáš; Hoffmeisterová, Hana; Folwarczna, Jitka; Čeřovská, Noemi

    2011-01-01

    Roč. 77, č. 2 (2011), s. 146-152 ISSN 1046-5928 R&D Projects: GA ČR GA521/09/1525 Institutional research plan: CEZ:AV0Z50380511 Keywords : Bacterial expression * Human papillomavirus * Oncoprotein E7 Subject RIV: EI - Biotechnology ; Bionics Impact factor: 1.587, year: 2011

  9. Fluorine Based Superhydrophobic Coatings

    Directory of Open Access Journals (Sweden)

    Jean-Denis Brassard

    2012-05-01

    Full Text Available Superhydrophobic coatings, inspired by nature, are an emerging technology. These water repellent coatings can be used as solutions for corrosion, biofouling and even water and air drag reduction applications. In this work, synthesis of monodispersive silica nanoparticles of ~120 nm diameter has been realized via Stöber process and further functionalized using fluoroalkylsilane (FAS-17 molecules to incorporate the fluorinated groups with the silica nanoparticles in an ethanolic solution. The synthesized fluorinated silica nanoparticles have been spin coated on flat aluminum alloy, silicon and glass substrates. Functionalization of silica nanoparticles with fluorinated groups has been confirmed by Fourier Transform Infrared spectroscopy (FTIR by showing the presence of C-F and Si-O-Si bonds. The water contact angles and surface roughness increase with the number of spin-coated thin films layers. The critical size of ~119 nm renders aluminum surface superhydrophobic with three layers of coating using as-prepared nanoparticle suspended solution. On the other hand, seven layers are required for a 50 vol.% diluted solution to achieve superhydrophobicity. In both the cases, water contact angles were more than 150°, contact angle hysteresis was less than 2° having a critical roughness value of ~0.700 µm. The fluorinated silica nanoparticle coated surfaces are also transparent and can be used as paint additives to obtain transparent coatings.

  10. Environmentally Friendly Anticorrosion Coating for High Strength Fasteners

    Science.gov (United States)

    2011-01-01

    electroplated coatings followed by a hexavalent chrome rinse. The environmental and health hazards associated with cadmium and hexavalent chromium are...have been used with cadmium (Cd) electroplated coatings, followed by a hexavalent chromium (Cr6+) rinse. The environmental and human health hazards...followed by a hexavalent chromium (Cr6+) rinse. The environmental and human health hazards associated with both cadmium and chromates are well

  11. A simple coated-tube assay for alpha-foeto protein for clinical use

    International Nuclear Information System (INIS)

    Dakubu, S.; Ahene, I.S.; Foli, A.K.

    1977-01-01

    A standard method for coating plastic tubes with antiserum has been applied to coat tubes with rabbit antiserum to human alpha-foeto protein. The coated plastic tubes have been used to set up a radioimmunoassay system which is sensitive and convenient for use on the occasional clinical sample. For a successful coated-tube assay, it was found necessary to modify the final incubation mixture from what was suitable in a standard double antibody assay system. (orig.) [de

  12. Efficient expression of Human papillomavirus 16 E7 oncoprotein fused to C-terminus of Tobacco mosaic virus (TMV) coat protein using molecular chaperones in Escherichia coli

    Czech Academy of Sciences Publication Activity Database

    Folwarczna, Jitka; Moravec, Tomáš; Plchová, Helena; Hoffmeisterová, Hana; Čeřovská, Noemi

    2012-01-01

    Roč. 85, č. 1 (2012), s. 152-157 ISSN 1046-5928 R&D Projects: GA ČR GA521/09/1525; GA ČR GAP501/12/1761 Institutional research plan: CEZ:AV0Z50380511 Keywords : Bacterial expression * Human papillomavirus * E7 oncoprotein Subject RIV: EI - Biotechnology ; Bionics Impact factor: 1.429, year: 2012

  13. Transient expression of Human papillomavirus type 16 L2 epitope fused to N- and C-terminus of coat protein of Potato virus X in plants

    Czech Academy of Sciences Publication Activity Database

    Čeřovská, Noemi; Hoffmeisterová, Hana; Moravec, Tomáš; Plchová, Helena; Folwarczna, Jitka; Synková, Helena; Ryšlavá, H.; Ludvíková, V.; Šmahel, M.

    2012-01-01

    Roč. 37, č. 1 (2012), s. 125-133 ISSN 0250-5991 R&D Projects: GA ČR GA521/06/0973; GA ČR GA521/09/1525 Institutional research plan: CEZ:AV0Z50380511 Keywords : Human papillomavirus (HPV-16) * L2-and E7-derived epitopes * transient expression Subject RIV: FD - Oncology ; Hematology Impact factor: 1.759, year: 2012

  14. Coatings to prevent frost

    DEFF Research Database (Denmark)

    Lusada, Ricardo; Holberg, Stefan; Bennedsen, Jeanette Marianne Dalgaard

    2016-01-01

    The ability of hydrophobic, organic–inorganic hybrid coatings to decelerate frost propagation was investigated. Compared to a bare aluminum surface, the coatings do not significantly reduce the freezing probability of supercooled water drops. On both surfaces, the probability for ice nucleation...... at temperatures just below 0°C, for example at −4°C, is low. Freezing of a single drop on aluminum leads, however, to instant freezing of the complete surface. On hydrophobic coatings, such a freezing drop is isolated; the frozen area grows slowly. At −4°C surface temperature in a +12°C/90% relative humidity...

  15. Adhesive strength of hydroxyl apatite(HA coating and biomechanics behavior of HA-coated prosthesis:an experimental study

    Directory of Open Access Journals (Sweden)

    Tian-yang ZHANG

    2011-05-01

    Full Text Available Objective To explore the influence of adhesive strength of hydroxyapatite(HA coating on the post-implantation stability of HA-coated prosthesis.Methods The adhesive strength and biomechanics behavior of HA coating were studied by histopathological observation,material parameters and biomechanical testing,the titanium(Ti-coated prosthesis was employed as control.Results Scratch test showed that the adhesive strength of HA coating was significantly lower than that of Ti coating(P < 0.01.Histopathological examination and bone morphometry showed that,at the early stage of prosthesis implantation,the bony growth around HA-coated prosthesis was significantly higher than that around Ti-coated prosthesis(P < 0.01,but the ultimate shear strength of HA-coated prosthesis was much lower than that of Ti-coated prosthesis(P < 0.01.After the push-out test with prosthesis,histopathological observation showed that there were accumulations of clump-and strip-like granular residues on the surface of bones that newly grew around the HA-coated prosthesis,and surface energy-dispersive X-ray spectroscopy(EDX analysis also confirmed that the shear stress induced HA decohesion from the substrate of prosthesis.Conclusions Although HA coating showed a satisfactory effect on early bone formation and prosthetic stability,due to the deficiencies of adhesive strength,the early stability of prosthesis may be gradually destroyed by the shear loads of human body and coating degradation.

  16. 3D-fibroblast tissues constructed by a cell-coat technology enhance tight-junction formation of human colon epithelial cells.

    Science.gov (United States)

    Matsusaki, Michiya; Hikimoto, Daichi; Nishiguchi, Akihiro; Kadowaki, Koji; Ohura, Kayoko; Imai, Teruko; Akashi, Mitsuru

    2015-02-13

    Caco-2, human colon carcinoma cell line, has been widely used as a model system for intestinal epithelial permeability because Caco-2 cells express tight-junctions, microvilli, and a number of enzymes and transporters characteristic of enterocytes. However, the functional differentiation and polarization of Caco-2 cells to express sufficient tight-junctions (a barrier) usually takes over 21 days in culture. This may be due to the cell culture environment, for example inflammation induced by plastic petri dishes. Three-dimensional (3D) sufficient cell microenvironments similar to in vivo natural conditions (proteins and cells), will promote rapid differentiation and higher functional expression of tight junctions. Herein we report for the first time an enhancement in tight-junction formation by 3D-cultures of Caco-2 cells on monolayered (1L) and eight layered (8L) normal human dermal fibroblasts (NHDF). Trans epithelial electric resistance (TEER) of Caco-2 cells was enhanced in the 3D-cultures, especially 8L-NHDF tissues, depending on culture times and only 10 days was enough to reach the same TEER value of Caco-2 monolayers after a 21 day incubation. Relative mRNA expression of tight-junction proteins of Caco-2 cells on 3D-cultures showed higher values than those in monolayer structures. Transporter gene expression patterns of Caco-2 cells on 3D-constructs were almost the same as those of Caco-2 monolayers, suggesting that there was no effect of 3D-cultures on transporter protein expression. The expression correlation between carboxylesterase 1 and 2 in 3D-cultures represented similar trends with human small intestines. The results of this study clearly represent a valuable application of 3D-Caco-2 tissues for pharmaceutical applications. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Comparison of cellular effects of starch-coated SPIONs and poly(lactic-co-glycolic acid matrix nanoparticles on human monocytes

    Directory of Open Access Journals (Sweden)

    Gonnissen D

    2016-10-01

    Full Text Available Dominik Gonnissen,1 Ying Qu,1,2 Klaus Langer,3 Cengiz Öztürk,4 Yuliang Zhao,2 Chunying Chen,2 Guiscard Seebohm,5 Martina Düfer,6 Harald Fuchs,1 Hans-Joachim Galla,7 Kristina Riehemann11Center for Nanotechnology, Institute of Physics, University of Münster, Münster, Germany; 2National Center for Nanoscience and Technology, Chinese Academy of Sciences, Beijing, People’s Republic of China; 3Institute of Pharmaceutical Technology and Biopharmacy, University of Münster, Münster, 4chemicell GmbH, Berlin, 5Department of Cardiovascular Medicine, Institute for Genetics of Heart Diseases, University Hospital Münster, 6Department of Pharmacology, Institute of Pharmaceutical and Medicinal Chemistry, 7Department of Cell Biology/Biophysics, Institute of Biochemistry, University of Münster, Münster, GermanyAbstract: Within the last years, progress has been made in the knowledge of the properties of medically used nanoparticles and their toxic effects, but still, little is known about their influence on cellular processes of immune cells. The aim of our comparative study was to present the influence of two different nanoparticle types on subcellular processes of primary monocytes and the leukemic monocyte cell line MM6. We used core-shell starch-coated superparamagnetic iron oxide nanoparticles (SPIONs and matrix poly(lactic-co-glycolic acid (PLGA nanoparticles for our experiments. In addition to typical biocompatibility testing like the detection of necrosis or secretion of interleukins (ILs, we investigated the impact of these nanoparticles on the actin cytoskeleton and the two voltage-gated potassium channels Kv1.3 and Kv7.1. Induction of necrosis was not seen for PLGA nanoparticles and SPIONs in primary monocytes and MM6 cells. Likewise, no alteration in secretion of IL-1β and IL-10 was detected under the same experimental conditions. In contrast, IL-6 secretion was exclusively downregulated in primary monocytes after contact with both

  18. Thermally joining and/or coating or thermally separating the workpieces having heat-sensitive coating, comprises restoring coating by thermally coating the coating material after thermally joining and/or coating or thermally separating

    OpenAIRE

    Riedel, Frank; Winkelmann, Ralf; Puschmann, Markus

    2011-01-01

    The method for thermally joining and/or coating or thermally separating the workpieces (1), which have a heat-sensitive coating (2), comprises restoring the coating by thermally coating a coating material (3) after thermally joining and/or coating or thermally separating the workpieces. A part of the thermal energy introduced in the workpiece for joining and/or coating or separating or in the workpieces is used for thermally coating the coating material. Two workpieces are welded or soldered ...

  19. POWDER COAT APPLICATIONS

    Science.gov (United States)

    The report discusses an investigation of critical factors that affect the use of powder coatings on the environment, cost, quality, and production. The investigation involved a small business representative working with the National Defense Center for Environmental Excellence (ND...

  20. Inorganic Coatings Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The inorganic Coatings Lab provides expertise to Navy and Joint Service platforms acquisition IPTs to aid in materials and processing choices which balance up-front...

  1. Robust Fiber Coatings

    National Research Council Canada - National Science Library

    Goettler, Richard

    2002-01-01

    The highly desired ceramic matrix composite is the one in which the high strength and strain-to-failure is achieved through judicious selection of a fiber coating that can survive the high-temperature...

  2. Coating of substrates

    International Nuclear Information System (INIS)

    Cairns, J.A.; Nelson, R.L.; Woodhead, J.L.

    1979-01-01

    The process is concerned with providing substrates with coatings obtainable from sols, for example to protect the substrate (such as in nuclear reactors or hydrocarbon cracking plant) or to provide a carrier for catalytically active material. Hitherto, coatings obtained from sols have had a high porosity and high surface area so that they have not been entirely satisfactory for the above applications. In the process described, dense, low-porosity coatings are provided by contacting the substrate with a sol of refractory material (e.g. CeO 2 or SiO 2 ) convertible to a gel of density at least 40% of the theoretical density of the refractory material, and converting the sol to the gel. Optionally, the gel may be converted to a ceramic coating by firing. (author)

  3. Friction surfaced Stellite6 coatings

    International Nuclear Information System (INIS)

    Rao, K. Prasad; Damodaram, R.; Rafi, H. Khalid; Ram, G.D. Janaki; Reddy, G. Madhusudhan; Nagalakshmi, R.

    2012-01-01

    Solid state Stellite6 coatings were deposited on steel substrate by friction surfacing and compared with Stellite6 cast rod and coatings deposited by gas tungsten arc and plasma transferred arc welding processes. Friction surfaced coatings exhibited finer and uniformly distributed carbides and were characterized by the absence of solidification structure and compositional homogeneity compared to cast rod, gas tungsten arc and plasma transferred coatings. Friction surfaced coating showed relatively higher hardness. X-ray diffraction of samples showed only face centered cubic Co peaks while cold worked coating showed hexagonally close packed Co also. - Highlights: ► Stellite6 used as coating material for friction surfacing. ► Friction surfaced (FS) coatings compared with casting, GTA and PTA processes. ► Finer and uniformly distributed carbides in friction surfaced coatings. ► Absence of melting results compositional homogeneity in FS Stellite6 coatings.

  4. Radiation hardening coating material

    International Nuclear Information System (INIS)

    McDonald, W.H.; Prucnal, P.J.; DeMajistre, Robert.

    1977-01-01

    This invention concerns a radiation hardening coating material. First a resin is prepared by reaction of bisphenol diglycidylic ether with acrylic or methacrylic acids. Then the reactive solvent is prepared by reaction of acrylic or methacrylic acids with epichlorhydrine or epibromhydrine. Then a solution consisting of the resin dissolved in the reactive solvent is prepared. A substrate (wood, paper, polyesters, polyamines etc.) is coated with this composition and exposed to ionizing radiations (electron beams) or ultraviolet radiations [fr

  5. Prime-boost therapeutic vaccination in mice with DNA/DNA or DNA/Fowlpox virus recombinants expressing the Human Papilloma Virus type 16 E6 and E7 mutated proteins fused to the coat protein of Potato virus X.

    Science.gov (United States)

    Illiano, Elena; Bissa, Massimiliano; Paolini, Francesca; Zanotto, Carlo; De Giuli Morghen, Carlo; Franconi, Rosella; Radaelli, Antonia; Venuti, Aldo

    2016-10-02

    The therapeutic antitumor potency of a prime-boost vaccination strategy was explored, based on the mutated, nontransforming forms of the E6 (E6 F47R ) and E7 (E7 GGG ) oncogenes of Human Papilloma Virus type 16 (HPV16), fused to the Potato virus X (PVX) coat protein (CP) sequence. Previous data showed that CP fusion improves the immunogenicity of tumor-associated antigens and may thus increase their efficacy. After verifying the correct expression of E6 F47R CP and E7 GGG CP inserted into DNA and Fowlpox virus recombinants by Western blotting and immunofluorescence, their combined use was evaluated for therapy in a pre-clinical mouse model of HPV16-related tumorigenicity. Immunization protocols were applied using homologous (DNA/DNA) or heterologous (DNA/Fowlpox) prime-boost vaccine regimens. The humoral immune responses were determined by ELISA, and the therapeutic efficacy evaluated by the delay in tumor appearance and reduced tumor volume after inoculation of syngeneic TC-1* tumor cells. Homologous DNA/DNA genetic vaccines were able to better delay tumor appearance and inhibit tumor growth when DNAE6 F47R CP and DNAE7 GGG CP were administered in combination. However, the heterologous DNA/Fowlpox vaccination strategy was able to delay tumor appearance in a higher number of animals when E6 F47R CP and in particular E7 GGG CP were administered alone. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Comparison of anti-CD3 and anti-CD28-coated beads with soluble anti-CD3 for expanding human T cells: Differing impact on CD8 T cell phenotype and responsiveness to restimulation

    Directory of Open Access Journals (Sweden)

    Kurlander Roger J

    2010-10-01

    Full Text Available Abstract Background The ability to expand virus- or tumor-specific T cells without damaging their functional capabilities is critical for success adoptive transfer immunotherapy of patients with opportunistic infection or tumor. Careful comparisons can help identify expansion methods better suited for particular clinical settings and identify recurrent deficiencies requiring new innovation. Methods We compared the efficacy of magnetic beads coated with anti-CD3 and anti-CD28 (anti-CD3/CD28 beads, and soluble anti-CD3 plus mixed mononuclear cells (designated a rapid expansion protocol or REP in expanding normal human T cells. Results Both anti-CD3/CD28 beads and soluble anti-CD3 promoted extensive expansion. Beads stimulated greater CD4 cell growth (geometric mean of 56- versus 27-fold (p Conclusions Anti-CD3/CD28 beads are highly effective for expanding CD4 cells, but soluble anti-CD3 has significant potential advantages for expanding CD8 T cells, particularly where preservation of phenotypically "young" CD8 cells would be desirable, or where the T cells of interest have been antigen-stimulated in vitro or in vivo in the recent past.

  7. Hydroxyapatite coatings for biomedical applications

    CERN Document Server

    Zhang, Sam

    2013-01-01

    Hydroxyapatite coatings are of great importance in the biological and biomedical coatings fields, especially in the current era of nanotechnology and bioapplications. With a bonelike structure that promotes osseointegration, hydroxyapatite coating can be applied to otherwise bioinactive implants to make their surface bioactive, thus achieving faster healing and recovery. In addition to applications in orthopedic and dental implants, this coating can also be used in drug delivery. Hydroxyapatite Coatings for Biomedical Applications explores developments in the processing and property characteri

  8. Coated particle waste form development

    International Nuclear Information System (INIS)

    Oma, K.H.; Buckwalter, C.Q.; Chick, L.A.

    1981-12-01

    Coated particle waste forms have been developed as part of the multibarrier concept at Pacific Northwest Laboratory under the Alternative Waste Forms Program for the Department of Energy. Primary efforts were to coat simulated nuclear waste glass marbles and ceramic pellets with low-temperature pyrolytic carbon (LT-PyC) coatings via the process of chemical vapor deposition (CVD). Fluidized bed (FB) coaters, screw agitated coaters (SAC), and rotating tube coaters were used. Coating temperatures were reduced by using catalysts and plasma activation. In general, the LT-PyC coatings did not provide the expected high leach resistance as previously measured for carbon alone. The coatings were friable and often spalled off the substrate. A totally different concept, thermal spray coating, was investigated at PNL as an alternative to CVD coating. Flame spray, wire gun, and plasma gun systems were evaluated using glass, ceramic, and metallic coating materials. Metal plasma spray coatings (Al, Sn, Zn, Pb) provided a two to three orders-of-magnitude increase in chemical durability. Because the aluminum coatings were porous, the superior leach resistance must be due to either a chemical interaction or to a pH buffer effect. Because they are complex, coated waste form processes rank low in process feasibility. Of all the possible coated particle processes, plasma sprayed marbles have the best rating. Carbon coating of pellets by CVD ranked ninth when compared with ten other processes. The plasma-spray-coated marble process ranked sixth out of eleven processes

  9. Immobilization of Platelet-Rich Plasma onto COOH Plasma-Coated PCL Nanofibers Boost Viability and Proliferation of Human Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Anastasiya Solovieva

    2017-12-01

    Full Text Available The scaffolds made of polycaprolactone (PCL are actively employed in different areas of biology and medicine, especially in tissue engineering. However, the usage of unmodified PCL is significantly restricted by the hydrophobicity of its surface, due to the fact that its inert surface hinders the adhesion of cells and the cell interactions on PCL surface. In this work, the surface of PCL nanofibers is modified by Ar/CO2/C2H4 plasma depositing active COOH groups in the amount of 0.57 at % that were later used for the immobilization of platelet-rich plasma (PRP. The modification of PCL nanofibers significantly enhances the viability and proliferation (by hundred times of human mesenchymal stem cells, and decreases apoptotic cell death to a normal level. According to X-ray photoelectron spectroscopy (XPS, after immobilization of PRP, up to 10.7 at % of nitrogen was incorporated into the nanofibers surface confirming the grafting of proteins. Active proliferation and sustaining the cell viability on nanofibers with immobilized PRP led to an average number of cells of 258 ± 12.9 and 364 ± 34.5 for nanofibers with ionic and covalent bonding of PRP, respectively. Hence, our new method for the modification of PCL nanofibers with PRP opens new possibilities for its application in tissue engineering.

  10. Vesicle coating and uncoating: controlling the formation of large COPII-coated carriers.

    Science.gov (United States)

    Townley, Anna K; Stephens, David J

    2009-08-26

    The basic mechanisms underlying the formation of coated vesicles are now defined in considerable detail. This article highlights recent developments in our understanding of the problem of exporting large macromolecular cargo such as procollagen from the endoplasmic reticulum and discusses the implications that this has for cell and tissue organisation and human disease.

  11. Coatings for directional eutectics

    Science.gov (United States)

    Rairden, J. R.; Jackson, M. R.

    1976-01-01

    Coatings developed to provide oxidation protection for the directionally-solidified eutectic alloy NiTaC-B (4.4 weight percent Cr) were evaluated. Of seven Co-, Fe- and Ni-base coatings that were initially investigated, best resistance to cyclic oxidation was demonstrated by duplex coatings fabricated by depositing a layer of NiCrAl(Y) by vacuum evaporation from an electron beam source followed by deposition of an Al overlayer using the pack cementation process. It was found that addition of carbon to the coating alloy substantially eliminated the problem of fiber denudation in TaC-type eutectic alloys. Burner rig cycled NiTaC-B samples coated with Ni-20Cr-5Al-0.1C-0.1Y+Al and rupture-tested at 1100 deg C performed as well as or better than uncoated, vacuum cycled and air-tested NiTaC-13; however, a slight degradation with respect to uncoated material was noted in air-stress rupture tests at 870 deg C for both cycled and uncycled samples.

  12. METHOD OF PROTECTIVELY COATING URANIUM

    Science.gov (United States)

    Eubank, L.D.; Boller, E.R.

    1959-02-01

    A method is described for protectively coating uranium with zine comprising cleaning the U for coating by pickling in concentrated HNO/sub 3/, dipping the cleaned U into a bath of molten zinc between 430 to 600 C and containing less than 0 01% each of Fe and Pb, and withdrawing and cooling to solidify the coating. The zinccoated uranium may be given a; econd coating with another metal niore resistant to the corrosive influences particularly concerned. A coating of Pb containing small proportions of Ag or Sn, or Al containing small proportions of Si may be applied over the zinc coatings by dipping in molten baths of these metals.

  13. Zirconium nitride hard coatings

    International Nuclear Information System (INIS)

    Roman, Daiane; Amorim, Cintia Lugnani Gomes de; Soares, Gabriel Vieira; Figueroa, Carlos Alejandro; Baumvol, Israel Jacob Rabin; Basso, Rodrigo Leonardo de Oliveira

    2010-01-01

    Zirconium nitride (ZrN) nanometric films were deposited onto different substrates, in order to study the surface crystalline microstructure and also to investigate the electrochemical behavior to obtain a better composition that minimizes corrosion reactions. The coatings were produced by physical vapor deposition (PVD). The influence of the nitrogen partial pressure, deposition time and temperature over the surface properties was studied. Rutherford backscattering spectrometry (RBS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscopy (SEM) and corrosion experiments were performed to characterize the ZrN hard coatings. The ZrN films properties and microstructure changes according to the deposition parameters. The corrosion resistance increases with temperature used in the films deposition. Corrosion tests show that ZrN coating deposited by PVD onto titanium substrate can improve the corrosion resistance. (author)

  14. Nanophase hardfaced coatings

    Energy Technology Data Exchange (ETDEWEB)

    Reisgen, U.; Stein, L.; Balashov, B.; Geffers, C. [RWTH Aachen University (Germany). ISF - Welding and Joining Institute

    2009-08-15

    This paper demonstrates the possibility of producing iron or chromium-based nanophase hardfaced coatings by means of common arc welding methods (TIG, PTA). The appropriate composition of the alloys to be deposited allows to control the structural properties and thus also the coating properties of the weld metal. Specific variations of the alloying elements allow also the realisation of a nanostructured solidification of the carbides and borides with cooling rates that are common for arc surfacing processes. The hardfaced coatings, which had been thus produced, showed phase dimensions of approximately 100-300 nm. Based on the results it is established that the influence of the surfacing parameters and of the coating thickness and thus the influence of the heat control on the nanostructuring process is, compared with the influence of the alloy composition, of secondary importance. The generation of nanoscale structures in hardfaced coatings allows the improvement of mechanical properties, wear resistance and corrosion resistance. Potential applications for these types of hardfaced coatings lie, in particular, in the field of cutting tools that are exposed to corrosion and wear. (Abstract Copyright [2009], Wiley Periodicals, Inc.) [German] Diese Arbeit demonstriert die Moeglichkeit zur Herstellung Eisen- und Chrom-basierter nanophasiger Hartauftragschweissschichten mithilfe ueblicher Lichtbogenschweissverfahren (WIG-, Plasma-Pulver-Auftragschweissen - PPA). Eine geeignete Zusammensetzung der aufzutragenden Legierungen ermoeglicht es, die Gefuegeeigenschaften und damit die Schichteigenschaften des Schweissgutes zu kontrollieren. Gezielte Variationen der Legierungselemente erlauben die Realisierung einer nanostrukturierten Erstarrung der Karbide und Boride bei fuer Lichtbogen-Auftragschweissprozessen ueblichen Abkuehlgeschwindigkeiten. In den so erzeugten Hartschichten werden Phasengroessen von ca. 100-300 nm erreicht. Auf Basis der gewonnenen Ergebnisse kann

  15. Tribology and coatings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-06-01

    The future use of fuel-efficient, low-emission, advanced transportation systems (for example, those using low-heat-rejection diesel engines or advanced gas turbines) presents new challenges to tribologists and materials scientists. High service temperatures, corrosive environments, and extreme contact pressures are among the concerns that make necessary new tribological designs, novel materials, and effective lubrication concepts. Argonne is working on methods to reduce friction, wear and corrosion, such as soft metal coatings on ceramics, layered compounds, diamond coatings, and hard surfaces.

  16. Active Packaging Coatings

    Directory of Open Access Journals (Sweden)

    Luis J. Bastarrachea

    2015-11-01

    Full Text Available Active food packaging involves the packaging of foods with materials that provide an enhanced functionality, such as antimicrobial, antioxidant or biocatalytic functions. This can be achieved through the incorporation of active compounds into the matrix of the commonly used packaging materials, or by the application of coatings with the corresponding functionality through surface modification. The latter option offers the advantage of preserving the packaging materials’ bulk properties nearly intact. Herein, different coating technologies like embedding for controlled release, immobilization, layer-by-layer deposition, and photografting are explained and their potential application for active food packaging is explored and discussed.

  17. Mechanically Invisible Polymer Coatings

    DEFF Research Database (Denmark)

    2014-01-01

    phase comprises particles, said particles comprising a filler material and an encapsulating coating of a second polymeric material, wherein the backbones of the first and second polymeric materials are the same. The composition may be used in electroactive polymers (EAPs) in order to obtain mechanically......The present invention relates to a composition comprising encapsulated particles in a polymeric material. The composition comprises a continuous phase and a discontinuous phase incorporated therein, wherein the continuous phase comprises a first polymeric material and wherein the discontinuous...... invisible polymer coatings....

  18. Fabrication and characterization of modified-hydroxyapatite/polyetheretherketone coating materials

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Rui [College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060 (China); College of Chemistry and Chemical Engineering, Shenzhen University, Shenzhen 518060 (China); Fang, Lin, E-mail: fanglinhit@163.com [College of Chemistry and Chemical Engineering, Shenzhen University, Shenzhen 518060 (China); Luo, Zhongkuan [College of Chemistry and Chemical Engineering, Shenzhen University, Shenzhen 518060 (China); Zheng, Ruisheng [College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060 (China); Song, Shenhua; Weng, Luqian; Lei, JinPing [Materials Science and Engineering, Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055 (China)

    2014-09-30

    Highlights: • 45 wt%-Hydroxyaptite/polyetheretherketone (HA/PEEK) coating materials modified by silane coupling agent (KH560) on PEEK substrate is successfully fabricated by solution casting method. • Strong bonding between the composite coating and the PEEK substrate is achieved. • HA/PEEK coating materials exhibit better bioactivity. - Abstract: 45 wt%-Hydroxyaptite/polyetheretherketone (HA/PEEK) coating materials modified by silane coupling agent (KH560) on PEEK substrate were successfully fabricated by solution casting method and characterized by Fourier transform infrared spectroscopy (FTIR), X-Ray Diffraction (XRD), scanning electron microscopy (SEM), and tensile testing. The modified HA fillers were obtained to be uniformly distributed in the HA/PEEK coating, which has better properties of tensile strength and fracture toughness than those of the unmodified specimen. A good bonding between the composite coating and the PEEK substrate was achieved by solution casting method, resulting in integral-fracture without falling apart or delaminating during tensile loading. The modified specimens dipped into simulated body fluid (SBF) were characterized by SEM, XRD and FTIR, indicating that the bioactivity of the dipped materials was demonstrated more apparent with extending the dipping time. Therefore, the coating materials may become the substitutes for the hard tissues of the human body in the future, which could realize the balance between the mechanical properties and the bioactivity by modifying the structural design of the coating.

  19. Fabrication and characterization of modified-hydroxyapatite/polyetheretherketone coating materials

    International Nuclear Information System (INIS)

    Ma, Rui; Fang, Lin; Luo, Zhongkuan; Zheng, Ruisheng; Song, Shenhua; Weng, Luqian; Lei, JinPing

    2014-01-01

    Highlights: • 45 wt%-Hydroxyaptite/polyetheretherketone (HA/PEEK) coating materials modified by silane coupling agent (KH560) on PEEK substrate is successfully fabricated by solution casting method. • Strong bonding between the composite coating and the PEEK substrate is achieved. • HA/PEEK coating materials exhibit better bioactivity. - Abstract: 45 wt%-Hydroxyaptite/polyetheretherketone (HA/PEEK) coating materials modified by silane coupling agent (KH560) on PEEK substrate were successfully fabricated by solution casting method and characterized by Fourier transform infrared spectroscopy (FTIR), X-Ray Diffraction (XRD), scanning electron microscopy (SEM), and tensile testing. The modified HA fillers were obtained to be uniformly distributed in the HA/PEEK coating, which has better properties of tensile strength and fracture toughness than those of the unmodified specimen. A good bonding between the composite coating and the PEEK substrate was achieved by solution casting method, resulting in integral-fracture without falling apart or delaminating during tensile loading. The modified specimens dipped into simulated body fluid (SBF) were characterized by SEM, XRD and FTIR, indicating that the bioactivity of the dipped materials was demonstrated more apparent with extending the dipping time. Therefore, the coating materials may become the substitutes for the hard tissues of the human body in the future, which could realize the balance between the mechanical properties and the bioactivity by modifying the structural design of the coating

  20. Plasma Sprayed Hydroxyapatite Coatings: Influence of Spraying Power on Microstructure

    International Nuclear Information System (INIS)

    Mohd, S. M.; Abd, M. Z.; Abd, A. N.

    2010-01-01

    The plasma sprayed hydroxyapatite (HA) coatings are used on metallic implants to enhance the bonding between the implant and bone in human body. The coating process was implemented at different spraying power for each spraying condition. The coatings formed from a rapid solidification of molten and partly molten particles that impact on the surface of substrate at high velocity and high temperature. The study was concentrated on different spraying power that is between 23 to 31 kW. The effect of different power on the coatings microstructure was investigated using scanning electron microscope (SEM) and phase composition was evaluated using X-ray diffraction (XRD) analysis. The coatings surface morphology showed distribution of molten, partially melted particles and some micro-cracks. The produced coatings were found to be porous as observed from the cross-sectional morphology. The coatings XRD results indicated the presence of crystalline phase of HA and each of the patterns was similar to the initial powder. Regardless of different spraying power, all the coatings were having similar XRD patterns.

  1. Methods and means for coating paper by film coating

    NARCIS (Netherlands)

    van der Maarel, Marc; Ter Veer, Arend Berend Cornelis; Vrieling-Smit, Annet; Delnoye, Pierre

    2015-01-01

    This invention relates to the field of paper coating, more in particular to means and methods for providing paper with at least one layer of pigment using film coating to obtain a well printable surface. Provided is a method for preparing coated paper comprising the steps of: a) providing a

  2. AntiReflection Coating D

    International Nuclear Information System (INIS)

    AIKEN, DANIEL J.

    1999-01-01

    Analytical expressions used to optimize AR coatings for single junction solar cells are extended for use in monolithic, series interconnected multi-junction solar cell AR coating design. The result is an analytical expression which relates the solar cell performance (through J(sub sc)) directly to the AR coating design through the device reflectance. It is also illustrated how AR coating design be used to provide an additional degree of freedom for current matching multi-junction devices

  3. UV Coatings, Polarization, and Coronagraphy

    Science.gov (United States)

    Bolcar, Matthew R.; Quijada, Manuel; West, Garrett; Balasubramanian, Bala; Krist, John; Martin, Stefan; Sabatke, Derek

    2016-01-01

    Presenation for the Large UltraViolet Optical Infrared (LUVOIR) and Habitable Exoplanet Imager (HabEx) Science and Technology Definition Teams (STDT) on technical considerations regarding ultraviolet coatings, polarization, and coronagraphy. The presentations review the state-of-the-art in ultraviolet coatings, how those coatings generate polarization aberrations, and recent study results from both the LUVOIR and HabEx teams.

  4. Coatings for transport industry

    Directory of Open Access Journals (Sweden)

    Krzysztof LUKASZKOWICZ

    2014-09-01

    Full Text Available The investigations concerned structural analysis, as well as mechanical properties and wear resistant of MeN/DLC double-layer coating deposited by hybrid PVD/PACVD method. In sliding dry friction conditions, after the break-in time, the friction coefficient for the investigated elements is set in the range between 0.03-0.06.

  5. Ion Deposited Carbon Coatings.

    Science.gov (United States)

    1983-07-01

    PAGE ("’hen Dita t,,I,, efl TABLE OF CONTENTS Section No. Title Page No. 1.0 OBJECTIVE 1 2.0 SCOPE 2 3.0 BACKGROUND 3 4.0 COATINGS DEPOSITION 4 4.1...scientific, ards of measure. The Committee, and Confer- technical, practical, and teaching purposes.ence voting members, are leading professional On the

  6. Polydopamine-coated capsules

    Science.gov (United States)

    White, Scott R.; Sottos, Nancy R.; Kang, Sen; Baginska, Marta B.

    2018-04-17

    One aspect of the invention is a polymer material comprising a capsule coated with PDA. In certain embodiments, the capsule encapsulates a functional agent. The encapsulated functional agent may be an indicating agent, healing agent, protecting agent, pharmaceutical drug, food additive, or a combination thereof.

  7. Active coatings technologies for tailorable military coating systems

    Science.gov (United States)

    Zunino, J. L., III

    2007-04-01

    The main objective of the U.S. Army's Active Coatings Technologies Program is to develop technologies that can be used in combination to tailor coatings for utilization on Army Materiel. The Active Coatings Technologies Program, ACT, is divided into several thrusts, including the Smart Coatings Materiel Program, Munitions Coatings Technologies, Active Sensor packages, Systems Health Monitoring, Novel Technology Development, as well as other advanced technologies. The goal of the ACT Program is to conduct research leading to the development of multiple coatings systems for use on various military platforms, incorporating unique properties such as self repair, selective removal, corrosion resistance, sensing, ability to modify coatings' physical properties, colorizing, and alerting logistics staff when tanks or weaponry require more extensive repair. A partnership between the U.S. Army Corrosion Office at Picatinny Arsenal, NJ along with researchers at the New Jersey Institute of Technology, NJ, Clemson University, SC, University of New Hampshire, NH, and University of Massachusetts (Lowell), MA, are developing the next generation of Smart Coatings Materiel via novel technologies such as nanotechnology, Micro-electromechanical Systems (MEMS), meta-materials, flexible electronics, electrochromics, electroluminescence, etc. This paper will provide the reader with an overview of the Active Coatings Technologies Program, including an update of the on-going Smart Coatings Materiel Program, its progress thus far, description of the prototype Smart Coatings Systems and research tasks as well as future nanotechnology concepts, and applications for the Department of Defense.

  8. New temperable solar coatings: Tempsol

    Science.gov (United States)

    Demiryont, Hulya

    2001-11-01

    This paper deals with the large area deposition and coating properties of the thermo-stable (temperable/bendable) solar coating material, CuO, and some new optical coating systems comprising CuO films for architectural and automotive/transportation applications. The CuO solar coating is combined with other coating layers, for example, an anti-reflection film, a reflection film, a coloration coating layer, etc., which are also thermo-stable. The film systems are developed at the research laboratory by D.C. Magnetron reactive sputtering process. The new developed technologies then transferred to the production line. Product performances are compared before and after heat treatment of the coating systems. Performance tables and other physical properties, including optical parameters, mechanical and environmental stability, storage properties, etc., are also presented for this new product series.

  9. Flow accelerated organic coating degradation

    Science.gov (United States)

    Zhou, Qixin

    Applying organic coatings is a common and the most cost effective way to protect metallic objects and structures from corrosion. Water entry into coating-metal interface is usually the main cause for the deterioration of organic coatings, which leads to coating delamination and underfilm corrosion. Recently, flowing fluids over sample surface have received attention due to their capability to accelerate material degradation. A plethora of works has focused on the flow induced metal corrosion, while few studies have investigated the flow accelerated organic coating degradation. Flowing fluids above coating surface affect corrosion by enhancing the water transport and abrading the surface due to fluid shear. Hence, it is of great importance to understand the influence of flowing fluids on the degradation of corrosion protective organic coatings. In this study, a pigmented marine coating and several clear coatings were exposed to the laminar flow and stationary immersion. The laminar flow was pressure driven and confined in a flow channel. A 3.5 wt% sodium chloride solution and pure water was employed as the working fluid with a variety of flow rates. The corrosion protective properties of organic coatings were monitored inline by Electrochemical Impedance Spectroscopy (EIS) measurement. Equivalent circuit models were employed to interpret the EIS spectra. The time evolution of coating resistance and capacitance obtained from the model was studied to demonstrate the coating degradation. Thickness, gloss, and other topography characterizations were conducted to facilitate the assessment of the corrosion. The working fluids were characterized by Fourier Transform Infrared Spectrometer (FTIR) and conductivity measurement. The influence of flow rate, fluid shear, fluid composition, and other effects in the coating degradation were investigated. We conclude that flowing fluid on the coating surface accelerates the transport of water, oxygen, and ions into the coating, as

  10. Coating of metals

    International Nuclear Information System (INIS)

    Smith, F.

    1978-01-01

    A method is described for coating the surface of an article of Ti, Zr or Ta, or an alloy thereof, with a tinning metal or alloy, the article having a shape other than that of a sheet. The method comprises contacting the surface of the article at an elevated temperature with the molten tinning metal and moving an ultrasonically excited probe over the surface to be coated, the probe being in contact with the surface of the article and with the tinning metal. The tinning metal may be Sn or Zn or a binary alloy of Sn with Zn, Cd or Bi at a temperature of 300 0 to 450 0 C. The head of the probe may be shaped to conform with the surface of the article. The method may be used to form composite articles, and may be applied to a pre-tinned steel article. (U.K.)

  11. Coat of Arms.

    Science.gov (United States)

    Smith, Bryan

    1998-01-01

    Describes an activity, the "coat of arms," that can serve as an ice-breaker or warm-up for the first day of an English-as-a-Second/Foreign-Language class, as a motivating start to the week, or act as an innovative segue between skill lessons. The technique can be adapted for students ranging from elementary school to adult language learners of all…

  12. Scientific coats of arms.

    Science.gov (United States)

    Fara, Patricia

    2005-09-01

    With their mythical creatures and arcane symbolism, coats of arms seem to have little connection with modern science. Yet despite its chivalric origins, the ancient language of heraldry has long fascinated famous scientists. Although this idiosyncratic tradition was parodied by Victorian geologists, who laughingly replaced unicorns and griffins with images of dinosaurs that they had recently discovered, it has been perpetuated since by Ernest Rutherford, who liked to present himself as a new alchemist.

  13. Anti-Corrosion Coating

    Science.gov (United States)

    1986-01-01

    SuperSpan RM 8000 is an anti-corrosion coating which effectively counteracts acid degradation, abrasive wear, and cracking in power industry facilities. It was developed by RM Industrial Products Company, Inc. with NERAC assistance. It had previously been necessary to shut down plants to repair or replace corroded duct-work in coal burning utilities. NASA-developed technology was especially useful in areas relating to thermoconductivity of carbon steel and the bonding characteristics of polymers. The product has sold well.

  14. Hydroxyapatite coatings with oriented nanoplate and nanorod arrays: Fabrication, morphology, cytocompatibility and osteogenic differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Wei [The Education Ministry Key Lab of Resource Chemistry and Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University, Shanghai 200234 (China); Tian, Bo [Shanghai Key Laboratory of Orthopedic Implant, Department of Orthopedic Surgery, Shanghai Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011 (China); Lei, Yong; Ke, Qin-Fei [The Education Ministry Key Lab of Resource Chemistry and Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University, Shanghai 200234 (China); Zhu, Zhen-An, E-mail: zhuzhenan2006@126.com [Shanghai Key Laboratory of Orthopedic Implant, Department of Orthopedic Surgery, Shanghai Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011 (China); Guo, Ya-Ping, E-mail: ypguo@shnu.edu.cn [The Education Ministry Key Lab of Resource Chemistry and Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University, Shanghai 200234 (China)

    2016-10-01

    Hydroxyapatite (HA) crystals exhibit rod-like shape with c-axis orientation and plate-like shape with a(b)-axis orientation in vertebrate bones and tooth enamel surfaces, respectively. Herein, we report the synthesis of HA coatings with the oriented nanorod arrays (RHACs) and HA coatings with oriented nanoplate arrays (PHACs) by using bioglass coatings as sacrificial templates. After soaking in simulated body fluid (SBF) at 120 °C, the bioglass coatings are hydrothermally converted into the HA coatings via a dissolution-precipitation reaction. If the Ca/P ratios in SBF are 2.50 and 1.25, the HA crystals on the coatings are oriented nanorod arrays and oriented nanoplate arrays, respectively. Moreover, the bioglass coatings are treated with SBF at 37 °C, plate-like HA coatings with a low crystallinity (SHACs) are prepared. As compared with the Ti6Al4V and SHACs, the human bone marrow stromal cells (hBMSCs) on the RHACs and PHACs have better cell adhesion, spreading, proliferation and osteogenic differentiation because of their moderately hydrophilic surfaces and similar chemical composition, morphology and crystal orientation to human hard tissues. Notably, the morphologies of HA crystals have no obvious effects on cytocompatibility and osteogenic differentiation. Hence, the HA coatings with oriented nanoplate arrays or oriented nanorod arrays have a great potential for orthopedic applications. - Highlights: • We prepare hydroxyapatite coatings with oriented nanoplate and nanorod arrays. • Hydroxyapatite coatings are in situ converted from bioglass coatings. • Hydroxyapatite coatings have good cytocompatibility and osteogenic differentiation. • Oriented hydroxyapatite coatings are used for orthopedic implants.

  15. Hydroxyapatite coatings with oriented nanoplate and nanorod arrays: Fabrication, morphology, cytocompatibility and osteogenic differentiation

    International Nuclear Information System (INIS)

    Chen, Wei; Tian, Bo; Lei, Yong; Ke, Qin-Fei; Zhu, Zhen-An; Guo, Ya-Ping

    2016-01-01

    Hydroxyapatite (HA) crystals exhibit rod-like shape with c-axis orientation and plate-like shape with a(b)-axis orientation in vertebrate bones and tooth enamel surfaces, respectively. Herein, we report the synthesis of HA coatings with the oriented nanorod arrays (RHACs) and HA coatings with oriented nanoplate arrays (PHACs) by using bioglass coatings as sacrificial templates. After soaking in simulated body fluid (SBF) at 120 °C, the bioglass coatings are hydrothermally converted into the HA coatings via a dissolution-precipitation reaction. If the Ca/P ratios in SBF are 2.50 and 1.25, the HA crystals on the coatings are oriented nanorod arrays and oriented nanoplate arrays, respectively. Moreover, the bioglass coatings are treated with SBF at 37 °C, plate-like HA coatings with a low crystallinity (SHACs) are prepared. As compared with the Ti6Al4V and SHACs, the human bone marrow stromal cells (hBMSCs) on the RHACs and PHACs have better cell adhesion, spreading, proliferation and osteogenic differentiation because of their moderately hydrophilic surfaces and similar chemical composition, morphology and crystal orientation to human hard tissues. Notably, the morphologies of HA crystals have no obvious effects on cytocompatibility and osteogenic differentiation. Hence, the HA coatings with oriented nanoplate arrays or oriented nanorod arrays have a great potential for orthopedic applications. - Highlights: • We prepare hydroxyapatite coatings with oriented nanoplate and nanorod arrays. • Hydroxyapatite coatings are in situ converted from bioglass coatings. • Hydroxyapatite coatings have good cytocompatibility and osteogenic differentiation. • Oriented hydroxyapatite coatings are used for orthopedic implants.

  16. for zeolite coating

    Directory of Open Access Journals (Sweden)

    Carlos Renato Rambo

    2006-01-01

    Full Text Available Biotemplating is the processing of microcellular ceramics by reproduction of natural morphologies, where the microstructural features of the biotemplate are maintained in the biomorphic ceramic. Different biotemplates with distinct pore anatomies were used to produce biomorphic supports for the zeolite coating: wood, cardboard, sea-sponge and sisal. The biomorphic ceramics were produced by distinguished processing routes: Al-gas infiltration-reaction, liquid-metal infiltration, dip-coating and sol-gel synthesis, in order to produce nitrides, carbides and oxides, depending on the processing conditions. The zeolite coating was performed by hydrothermal growth of MFI-type (Silicalite-1 and ZSM-5 zeolite crystals onto the internal pore walls of the biomorphic templates. The final biomorphic ceramic-zeolite composites were physically characterized, evaluated in terms of their gas adsorption capabilities and correlated to their microstructure and specific pore anatomy. The combination of the properties of the biomorphic ceramics with the adsorption properties of zeolites results in materials with distinct properties as potential candidates for adsorption and catalytic applications due to their characteristic porosity, molecular sieving capabilities and high thermo-mechanical strength.

  17. Coating and curing apparatus and methods

    Science.gov (United States)

    Brophy, Brenor L; Maghsoodi, Sina; Neyman, Patrick J; Gonsalves, Peter R; Hirsch, Jeffrey G; Yang, Yu S

    2015-02-24

    Disclosed are coating apparatus including flow coating and roll-coating that may be used for uniform sol-gel coating of substrates such as glass, solar panels, windows or part of an electronic display. Also disclosed are methods for substrate preparation, flow coating and roll coating. Lastly systems and methods for skin curing sol-gel coatings deposited onto the surface of glass substrates using a high temperature air-knife are disclosed.

  18. Lotus Dust Mitigation Coating and Molecular Adsorber Coating

    Science.gov (United States)

    O'Connor, Kenneth M.; Abraham, Nithin S.

    2015-01-01

    NASA Goddard Space Flight Center has developed two unique coating formulations that will keep surfaces clean and sanitary and contain contaminants.The Lotus Dust Mitigation Coating, modeled after the self-cleaning, water-repellant lotus leaf, disallows buildup of dust, dirt, water, and more on surfaces. This coating, has been successfully tested on painted, aluminum, glass, silica, and some composite surfaces, could aid in keeping medical assets clean.The Molecular Adsorber Coating is a zeolite-based, sprayable molecular adsorber coating, designed to prevent outgassing in materials in vacuums. The coating works well to adsorb volatiles and contaminates in manufacturing and processing, such as in pharmaceutical production. The addition of a biocide would also aid in controlling bacteria levels.

  19. Micro patterning of cell and protein non-adhesive plasma polymerized coatings for biochip applications

    DEFF Research Database (Denmark)

    Bouaidat, Salim; Berendsen, C.; Thomsen, P.

    2004-01-01

    Micro scale patterning of bioactive surfaces is desirable for numerous biochip applications. Polyethyleneoxide-like (PEO-like) coating with non-fouling functionality has been deposited using low frequency AC plasma polymerization. The non-fouling properties of the coating were tested with human c...... and versatility of the plasma-polymerized coatings, make this technology highly suitable for bio-MEMS and biochip applications, where patterned high contrast non-fouling surfaces are needed....

  20. Time-dependent histamine release from stored human blood products

    DEFF Research Database (Denmark)

    Nielsen, Hans Jørgen; Edvardsen, L; Vangsgaard, K

    1996-01-01

    storage. Whole blood (six units), plasma-reduced whole blood (six units), and plasma- and buffy coat-reduced (saline-adenine-glucose-mannitol) (SAGM) blood (six units) from unpaid healthy donors were stored in the blood bank for 35 days at 4 degrees C. Plasma histamine and total cell-bound histamine......Perioperative transfusion of whole blood has been shown to amplify trauma-induced immunosuppression, which could be attenuated by perioperative administration of histamine2 receptor antagonists. Supernatants from different blood products were, therefore, analysed for histamine content during.......0 (range 176.0-910.0) nmol/l in whole blood and 475.0 (range 360.0-1560.0) nmol/l in plasma-reduced whole blood, while it was undetectable in SAGM blood. Spontaneous histamine release increased in a time-dependent manner from a median of 6.7 (range 2.2-17.4) nmol/l at the time of storage to 175.0 (range 33...

  1. Synthetic osteogenic extracellular matrix formed by coated silicon dioxide nanosprings

    Directory of Open Access Journals (Sweden)

    Hass Jamie L

    2012-01-01

    Full Text Available Abstract Background The design of biomimetic materials that parallel the morphology and biology of extracellular matrixes is key to the ability to grow functional tissues in vitro and to enhance the integration of biomaterial implants into existing tissues in vivo. Special attention has been put into mimicking the nanostructures of the extracellular matrix of bone, as there is a need to find biomaterials that can enhance the bonding between orthopedic devices and this tissue. Methods We have tested the ability of normal human osteoblasts to propagate and differentiate on silicon dioxide nanosprings, which can be easily grown on practically any surface. In addition, we tested different metals and metal alloys as coats for the nanosprings in tissue culture experiments with bone cells. Results Normal human osteoblasts grown on coated nanosprings exhibited an enhanced rate of propagation, differentiation into bone forming cells and mineralization. While osteoblasts did not attach effectively to bare nanowires grown on glass, these cells propagated successfully on nanosprings coated with titanium oxide and gold. We observed a 270 fold increase in the division rate of osteoblasts when grow on titanium/gold coated nanosprings. This effect was shown to be dependent on the nanosprings, as the coating by themselves did not alter the growth rate of osteoblast. We also observed that titanium/zinc/gold coated nanosprings increased the levels of osteoblast production of alkaline phosphatase seven folds. This result indicates that osteoblasts grown on this metal alloy coated nanosprings are differentiating to mature bone making cells. Consistent with this hypothesis, we showed that osteoblasts grown on the same metal alloy coated nanosprings have an enhanced ability to deposit calcium salt. Conclusion We have established that metal/metal alloy coated silicon dioxide nanosprings can be used as a biomimetic material paralleling the morphology and biology of

  2. Composition superconductive plumbous coatings

    International Nuclear Information System (INIS)

    Volodin, V.N.; Tuleushev, A.Zh.; Tuleushev, Yu.Zh.; Lisizin, V.N.

    2002-01-01

    Independent dispersion of two or more targets, precipitation of pulverized material on substrate and possibility of composition change in wide range of component concentrations made possible ion-plasma forming of film composition materials from materials with different chemical and physical qualities, particularly in lead-aluminum, lead-beryllium and lead-graphite systems. Named systems are characterized in wide sphere of immiscibility in solid and liquid state and absence of intermediate compounds. It is impossible to receive materials from them in traditional method in conditions of gravitational field. In lead-aluminum system there was received a number of film coatings with aluminum content up to 95 at. % at coating thickness up to 2 μm. Owing to X-ray investigations it is fixed that lead and aluminum have been performed by separate phases. Lead in sprayed layer represents well-crystallized phase with grain size more than 100 nm; texturing is not found. Study of physical qualities has shown that materials with lead base 21.6 at. % Al) have enough high crystalline current in comparison with compact lead, which reaches (2.5-3.0)·10 5 A)·cm 2 , while materials with aluminum base (21.6 at. % Al) loose this effect and critical temperature of transition is reduced from 7.1 to 5.8 K. It was impossible to carry out X-rayed analysis for lead-beryllium film because of weak intensity of beryllium lines against a background of lead owing to a quite large difference of atomic balance. Cryogen tests have shown the increase of critical current strength up to (3.1-3.6)·10 4 A)·cm 2 or composition coating of lead-beryllium (56.99 at. % or 5,45 mas. % Be), at that the critical temperature of transition does not differ from lead temperature. Samples of lead edge of state diagram have been received in the lead-graphite system. X-ray investigation subjected coating contained 6.81 at. % (55.82 mas. %) of lead. Choice of the composition is conditioned on possibilities of

  3. Carbon nanotube-coating accelerated cell adhesion and proliferation on poly (L-lactide)

    International Nuclear Information System (INIS)

    Hirata, Eri; Akasaka, Tsukasa; Uo, Motohiro; Takita, Hiroko; Watari, Fumio; Yokoyama, Atsuro

    2012-01-01

    Highlights: ► The surface of a polylactic acid (PLLA) was coated multiwalled carbon nanotubes (MWCNTs). ► MWCNT-coated PLLA showed remarkable higher wettability than uncoated PLLA. ► More Human osteosarcoma cell line (Saos2) adhered on the CNT-coated than those on uncoated PLLA at 2 h after seeding. ► MWCNT-coating on PLLA improved the surface wettability and initial cell attachment at early stage. - Abstract: The surface of a polylactic acid (PLLA) was coated multiwalled carbon nanotubes (MWCNTs) in order to improve the surface properties. In addition, its surface characteristics and cell culturing properties were examined. Whole surface of PLLA was homogeneously covered by MWCNTs maintained a unique tubular structure. MWCNT-coated PLLA showed remarkable higher wettability than uncoated PLLA. Human osteosarcoma cell line (Saos2) adhered well on the CNT-coated PLLA whereas there are few cells attached on the uncoated PLLA at 2 h after seeding. The number of the cells on uncoated PLLA was still smaller than on the MWCNT-coated PLLA at 1 and 3 days. Moreover, The DNA content in the cells attached to the MWCNT-coated PLLA was significantly higher than that on the uncoated PLLA (p 0.1). Therefore MWCNT-coating on PLLA improved the surface wettability and initial cell attachment at early stage.

  4. Improved Mechanical Compatibility and Cytocompatibility of Ta/Ti Double-Layered Composite Coating

    Science.gov (United States)

    Ding, Ding; Xie, Youtao; Li, Kai; Huang, Liping; Zheng, Xuebin

    2017-08-01

    In order to improve the mechanical compatibility and cytocompatibility of titanium implants, a composite coating with double layers composed of tantalum and titanium was designed and prepared using plasma spraying technology. In the composite coating, the upper tantalum layer provides a good biocompatibility, and the sublayer of titanium with a porous structure ensures the low elastic modulus. Results show that the fabricated composite coating exhibits a relatively low elastic modulus of 26.7 GPa, which is close to the elastic modulus of human cortical bone. In vitro cytocompatibility evaluation of the composite coating shows that the human bone marrow stromal cells exhibit enhanced adhesion and spreading performance on the double-layered composite coating in comparison with the single-layered titanium coating. In order to eliminate the misgivings of chemical stability of the composite coating in clinical application, electrochemical corrosion of the coating was examined. The results obtained revealed a very weak galvanic corrosion between the tantalum and titanium in the composite coating, which would ensure the safety of the coating in vivo.

  5. Nanoparticle/Polymer Nanocomposite Bond Coat or Coating

    Science.gov (United States)

    Miller, Sandi G.

    2011-01-01

    This innovation addresses the problem of coatings (meant to reduce gas permeation) applied to polymer matrix composites spalling off in service due to incompatibility with the polymer matrix. A bond coat/coating has been created that uses chemically functionalized nanoparticles (either clay or graphene) to create a barrier film that bonds well to the matrix resin, and provides an outstanding barrier to gas permeation. There is interest in applying clay nanoparticles as a coating/bond coat to a polymer matrix composite. Often, nanoclays are chemically functionalized with an organic compound intended to facilitate dispersion of the clay in a matrix. That organic modifier generally degrades at the processing temperature of many high-temperature polymers, rendering the clay useless as a nano-additive to high-temperature polymers. However, this innovation includes the use of organic compounds compatible with hightemperature polymer matrix, and is suitable for nanoclay functionalization, the preparation of that clay into a coating/bondcoat for high-temperature polymers, the use of the clay as a coating for composites that do not have a hightemperature requirement, and a comparable approach to the preparation of graphene coatings/bond coats for polymer matrix composites.

  6. Modeling of Thermal Barrier Coatings

    Science.gov (United States)

    Ferguson, B. L.; Petrus, G. J.; Krauss, T. M.

    1992-01-01

    The project examined the effectiveness of studying the creep behavior of thermal barrier coating system through the use of a general purpose, large strain finite element program, NIKE2D. Constitutive models implemented in this code were applied to simulate thermal-elastic and creep behavior. Four separate ceramic-bond coat interface geometries were examined in combination with a variety of constitutive models and material properties. The reason for focusing attention on the ceramic-bond coat interface is that prior studies have shown that cracking occurs in the ceramic near interface features which act as stress concentration points. The model conditions examined include: (1) two bond coat coefficient of thermal expansion curves; (2) the creep coefficient and creep exponent of the bond coat for steady state creep; (3) the interface geometry; and (4) the material model employed to represent the bond coat, ceramic, and superalloy base.

  7. Tablet coating by injection molding technology - Optimization of coating formulation attributes and coating process parameters.

    Science.gov (United States)

    Desai, Parind M; Puri, Vibha; Brancazio, David; Halkude, Bhakti S; Hartman, Jeremy E; Wahane, Aniket V; Martinez, Alexander R; Jensen, Keith D; Harinath, Eranda; Braatz, Richard D; Chun, Jung-Hoon; Trout, Bernhardt L

    2018-01-01

    We developed and evaluated a solvent-free injection molding (IM) coating technology that could be suitable for continuous manufacturing via incorporation with IM tableting. Coating formulations (coating polymers and plasticizers) were prepared using hot-melt extrusion and screened via stress-strain analysis employing a universal testing machine. Selected coating formulations were studied for their melt flow characteristics. Tablets were coated using a vertical injection molding unit. Process parameters like softening temperature, injection pressure, and cooling temperature played a very important role in IM coating processing. IM coating employing polyethylene oxide (PEO) based formulations required sufficient room humidity (>30% RH) to avoid immediate cracks, whereas other formulations were insensitive to the room humidity. Tested formulations based on Eudrajit E PO and Kollicoat IR had unsuitable mechanical properties. Three coating formulations based on hydroxypropyl pea starch, PEO 1,000,000 and Opadry had favorable mechanical (35% elongation, >95×10 4 J/m 3 toughness) and melt flow (>0.4g/min) characteristics, that rendered acceptable IM coats. These three formulations increased the dissolution time by 10, 15 and 35min, respectively (75% drug release), compared to the uncoated tablets (15min). Coated tablets stored in several environmental conditions remained stable to cracking for the evaluated 8-week time period. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Article Including Environmental Barrier Coating System

    Science.gov (United States)

    Lee, Kang N. (Inventor)

    2015-01-01

    An enhanced environmental barrier coating for a silicon containing substrate. The enhanced barrier coating may include a bond coat doped with at least one of an alkali metal oxide and an alkali earth metal oxide. The enhanced barrier coating may include a composite mullite bond coat including BSAS and another distinct second phase oxide applied over said surface.

  9. Coatings for fusion reactor environments

    International Nuclear Information System (INIS)

    Mattox, D.M.

    1979-01-01

    The internal surfaces of a tokamak fusion reactor control the impurity injection and gas recycling into the fusion plasma. Coating of internal surfaces may provide a desirable and possibly necessary design flexibility for achieving the temperatures, ion densities and containment times necessary for net energy production from fusion reactions to take place. In this paper the reactor environments seen by various componentare reviewed along with possible materials responses. Characteristics of coating-substrate systems, important to fusion applications, are delineated and the present status of coating development for fusion applications is reviewed. Coating development for fusion applications is just beginning and poses a unique and important challenge for materials development

  10. Properties of radiation cured coatings

    International Nuclear Information System (INIS)

    Larson, E.G.; Spencer, D.S.; Boettcher, T.E.; Melbauer, M.A.; Skarjune, R.P.

    1987-01-01

    Coatings were prepared from acrylate or methacrylate functionalized resins to study the effect of end group functionality on the physical properties of u.v. and electron beam cured coatings. Cure response was measured by solid state NMR and gel extraction, as expected, methacrylate resins cured much slower. Thermal Gravimetric Analysis (TGA) revealed acrylate coatings have greater thermal stability. Properties such as tensile strength and hardness showed little effect of end group functionality or curing method. The O 2 and H 2 O permeabilities of the coating were correlated with the processing conditions. (author)

  11. Decontamination and coating of lead

    International Nuclear Information System (INIS)

    Rankin, W.N.; Bush, S.P.; Lyon, C.E.; Walker, V.

    1988-01-01

    Technology is being developed to decontaminate lead used in shielding applications in contaminated environments for recycle as shieldings. Technology is also being developed to coat either decontaminated lead or new lead before it is used in contaminated environments. The surface of the coating is expected to be much easier to decontaminate than the original lead surface. If contamination becomes severely embedded in the coating and cannot be removed, it can be easily cut with a knife and removed from the lead. The used coating can be disposed of as radioactive (hot hazardous) waste. The lead can then be recoated for further use as a shielding material

  12. Coatings Technology Integration Office (CTIO)

    Data.gov (United States)

    Federal Laboratory Consortium — CTIO serves as the Air Force's central resource for aircraft coating systems and their applications. CTIO's primary objectives are pollution prevention and improved...

  13. Overcoming the bottleneck of platelet lysate supply in large-scale clinical expansion of adipose-derived stem cells

    DEFF Research Database (Denmark)

    Glovinski, Peter Viktor; Herly, Mikkel; Mathiasen, Anders B

    2017-01-01

    , we tested PLs prepared via three methods from outdated buffy coat-derived platelet concentrates (PCs) to establish an efficient and feasible expansion of ASCs for clinical use. METHODS: PLs were prepared by the freeze-thaw method from freshly drawn platelets or from outdated buffy coat-derived PCs...

  14. Coating material composition

    International Nuclear Information System (INIS)

    Kimura, Tadashi; Ozeki, Takao; Kobayashi, Juichi; Nakamoto, Hideo; Maeda, Yutaka.

    1969-01-01

    A coating material composition is provided which can easily be cross-linked by irradiation with active energy, particularly electron beams and ultraviolet light, using a mixture of a prepolymer (a) with an addition reaction product (b). Such compositions have coating properties as good as thermosetting acrylic or amino alkyd resins. The prepolymer (a) is produced by primarily reacting at least 0.1 mol of saturated cyclocarboxylic acid anhydrides and/or alpha-, beta-ethylene unsaturated carboxylic acid anhydrides by addition reaction with one mol of hydroxyl radicals of a basic polymer having a molecular weight of 1,000 to 100,000, the basic polymer being obtained from 1%-40% of a hydroxyl radical containing vinyl monomer and at least 30% of (meth)acrylate monomer. One mol of the sum of hydroxyl radicals and carboxyl radicals of the primary reaction product undergoes a secondary addition reaction with at least 0.1 mol of an epoxy radical-containing vinyl monomer to form the prepolymer(a). The addition reaction product(b) is produced by reacting an epoxy radical-containing vinyl monomer with alpha-, beta-ethylene unsaturated carboxylic acids or their anhydrides. The coating material composition contains a majority of a mixture consisting of 10%-90% of (a) and 90%-10% of (b) above by weight. Four examples of the production of basic polymers, seven examples of the production of prepolymers, seven examples of the production of oligomers, and five examples of applications are given. (Iwakiri, K.)

  15. Microplasma sprayed hydroxyapatite coatings

    CERN Document Server

    Dey, Arjun

    2015-01-01

    ""This unique book on development of microplasma sprayed HAp coating has been organized in a very compact yet comprehensive manner. This book also highlights the horizons of future research that invites the attention of global community, particularly those in bio-medical materials and bio-medical engineering field. This book will surely act as a very useful reference material for both graduate/post-graduate students and researchers in the field of biomedical, orthopedic and manufacturing engineering and research. I truly believ that this is the first ever effort which covers almost all the

  16. SPS: scrubbing or coating ?

    CERN Document Server

    Jimenez, J M

    2012-01-01

    The operation of the SPS with high intensity bunched beams is limited by the electron cloud building-up in both the arcs and long straight sections. Two consolidation options have been considered: mitigation of the electron cloud using coatings or relying, as before, on the scrubbing runs. A status report on both options will be given with a particular emphasis on measurements plans for 2012 and pending issues. The testing needs, corresponding beam parameters and MD time in 2012 will be addressed. The criteria for the decision making and the corresponding schedule will be discussed.

  17. SPS: scrubbing or coating?

    International Nuclear Information System (INIS)

    Jimenez, J.M.

    2012-01-01

    The operation of the SPS with high intensity bunched beams is limited by the electron cloud building-up in both the arcs and long straight sections. Two consolidation options have been considered: suppression of the electron cloud build-up using coatings or relying, as before, on the scrubbing mitigation. A status report on both options will be given with a particular emphasis on measurements plans for 2012 and pending issues. The testing needs, corresponding beam parameters and MD time in 2012 will be addressed. The criteria for the decision making and the corresponding schedule will be discussed. (author)

  18. Radiation hardenable coating mixture

    International Nuclear Information System (INIS)

    Howard, D.D.

    1977-01-01

    This invention relates to coatings that harden under radiation and to their compositions. Specifically, this invention concerns unsaturated urethane resins polymerisable by addition and to compositions, hardening under the effect of radiation, containing these resins. These resins feature the presence of at least one unsaturated ethylenic terminal group of structure CH 2 =C and containing the product of the reaction of an organic isocyanate compound with at least two isocyanate groups and one polyester polyol with at least two hydroxyl groups, and one unsaturated monomer compound polymerisable by addition having a single active hydrogen group reacting with the isocyanate [fr

  19. 21 CFR 175.230 - Hot-melt strippable food coatings.

    Science.gov (United States)

    2010-04-01

    ..., white For use only as a component of hot-melt strippable food coatings applied to frozen meats and... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Hot-melt strippable food coatings. 175.230 Section 175.230 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

  20. Novel nanocomposite coating for dental implant applications in vitro and in vivo evaluation.

    Science.gov (United States)

    Mehdikhani-Nahrkhalaji, M; Fathi, M H; Mortazavi, V; Mousavi, S B; Hashemi-Beni, B; Razavi, S M

    2012-02-01

    This study aimed at preparation and in vitro and in vivo evaluation of novel bioactive, biodegradable, and antibacterial nanocomposite coating for the improvement of stem cells attachment and antibacterial activity as a candidate for dental implant applications. Poly (lactide-co-glycolide)/bioactive glass/hydroxyapatite (PBGHA) nanocomposite coating was prepared via solvent casting process. The nanoparticle amounts of 10, 15, and 20 weight percent (wt%) were chosen in order to determine the optimum amount of nanoparticles suitable for preparing an uniform coating. Bioactivity and degradation of the coating with an optimum amount of nanoparticles were evaluated by immersing the prepared samples in simulated body fluid and phosphate buffer saline (PBS), respectively. The effect of nanocomposite coating on the attachment and viability of human adipose-derived stem cells (hASCs) was investigated. Kirschner wires (K-wires) of stainless steel were coated with the PBGHA nanocomposite coating, and mechanical stability of the coating was studied during intramedullary implantation into rabbit tibiae. The results showed that using 10 wt% nanoparticles (5 wt% HA and 5 wt% BG) in the nanocomposite could provide the desired uniform coating. The study of in vitro bioactivity showed rapid formation of bone-like apatite on the PBGHA coating. It was degraded considerably after about 60 days of immersion in PBS. The hASCs showed excellent attachment and viability on the coating. PBGHA coating remained stable on the K-wires with a minimum of 96% of the original coating mass. It was concluded that PBGHA nanocomposite coating provides an ideal surface for the stem cells attachment and viability. In addition, it could induce antibacterial activity, simultaneously.

  1. Metabolic activation of volatile organic compounds and polycyclic aromatic hydrocarbons coated onto airborne PM{sub 2.5} in isolated human alveolar macrophages; Etude de l'activation metabolique des composes organiques volatils et des hydrocarbures aromatiques polycycliques d'un aerosol anthropogenique par des macrophages alveolaires humains en culture primaire

    Energy Technology Data Exchange (ETDEWEB)

    Saint-Georges, F.; Mulliez, P. [Hopital Saint Philibert - GHICL-FLM, Service de Pneumologie, 59 - Lomme (France); Saint-Georges, F.; Abbas, I.; Garcon, G.; Billet, S.; Verdin, A.; Shirali, P. [LCE-EA2598, Lab. de Recherche en toxicologie Industrielle et Environnementale - ULCO-MREI, 59 - Dunkerque (France); Gosset, P. [Hopital Saint Vincent, Laboratoire d' Anatomie et de Cytologie Pathologiques - GHICL-FLM, 59 - Lille (France); Courcot, D. [LCE-EA2598, Lab. de Catalyse et Environnement - ULCO-MREI, 59 - Dunkerque (France)

    2009-01-15

    To contribute to improve the knowledge of the underlying mechanisms of action involved in air pollution Particulate Matter (PM)-induced cytotoxicity, we were interested in the metabolic activation of Volatile Organic Compounds (VOC) and/or Polycyclic Aromatic Hydrocarbons (PAH)-coated onto Dunkerque City's PM{sub 2.5} in human Alveolar Macrophages (AM) isolated from Bronchoalveolar Lavage Fluid (BALF). This in vitro cell lung model is very close to the normal in vivo situation, notably in the characteristics that AM display in terms of gene expression of phase I and phase II-metabolizing enzymes. The bronchoscopic examinations and BAL procedures were carried out without any complications. The exposure of AM, during 24, 48 or 72 h, to increasing concentrations of the collected aerosol induced significant variations of the activities of the extracellular lactate dehydrogenase and the mitochondrial dehydrogenase. The lethal concentrations at 10% and 50% were 14.93 and 74.63 {mu}g/mL for AM, respectively, and indicated the relatively higher sensibility of such target lung cells. VOC and/or PAH-coated at low levels onto the surface of the particulate fraction significantly induced gene expression of cytochrome P450 (GYP) 1A1, CYP2E1, NADPH Quinone oxido-reductase (NQO)-1) and Glutathione S-Transferase (GST)P1 and M3, versus controls, suggesting thereby the formation of biologically reactive metabolites. Moreover, these results suggested the role of physical vector of carbonaceous core of PM, which can, therefore, increase both the penetration and the retention of attached-VOC into the cells, thereby enabling them to exert a more durable induction. Hence, we concluded that the metabolic activation of the very low doses of VOC and/or PAH-coated onto Dunkerque City's PM{sub 2.5} is one of the underlying mechanisms of action closely involved in its cytotoxicity in isolated human AM in culture. (author)

  2. Federal Highway Administration 100-year coating study.

    Science.gov (United States)

    2012-11-01

    The Federal Highway Administration 100-Year Coating Study was initiated in August 2009 to search for durable : coating systems at a reasonable cost. The objective of the study was to identify and evaluate coating materials that can : provide 100 year...

  3. Decoding white coat hypertension

    Science.gov (United States)

    Bloomfield, Dennis A; Park, Alex

    2017-01-01

    There is arguably no less understood or more intriguing problem in hypertension that the “white coat” condition, the standard concept of which is significantly blood pressure reading obtained by medical personnel of authoritative standing than that obtained by more junior and less authoritative personnel and by the patients themselves. Using hospital-initiated ambulatory blood pressure monitoring, the while effect manifests as initial and ending pressure elevations, and, in treated patients, a low daytime profile. The effect is essentially systolic. Pure diastolic white coat hypertension appears to be exceedingly rare. On the basis of the studies, we believe that the white coat phenomenon is a common, periodic, neuro-endocrine reflex conditioned by anticipation of having the blood pressure taken and the fear of what this measurement may indicate concerning future illness. It does not change with time, or with prolonged association with the physician, particularly with advancing years, it may be superimposed upon essential hypertension, and in patients receiving hypertensive medication, blunting of the nighttime dip, which occurs in about half the patients, may be a compensatory mechanisms, rather than an indication of cardiovascular risk. Rather than the blunted dip, the morning surge or the widened pulse pressure, cardiovascular risk appears to be related to elevation of the average night time pressure. PMID:28352632

  4. Ceramic protective coating

    International Nuclear Information System (INIS)

    Harbach, F.; Nicoll, A.

    1987-01-01

    The basic material of the above-mentioned layer consists of pure aluminium oxide or essentially aluminium oxide. To improve this protective layer metal oxides from the groups IIA, IIIA, IIIB, VB, VIB, VIIB or VIII of the periodic system are added to its basic material before the said protective coating is applied. In this way a corundum structure is formed in the case of aluminium oxide. Gallium oxide, vanadium oxide, chromium oxide or iron oxide are particularly suited for the correlation of such a corundum structure. The formation of the corundum structure increases the resistance of the protective coating to the corrosive effects of vanadium pentoxide and sodium sulfate. By the addition of a specific quantity of magnesium oxide it is possible not only to stimulate the formation of corundum but also to reduce the increase in grain size in the case of the aluminium oxide. The other metallic oxides are especially favorable to the formation of the corundum structure, so that preferably magnesium oxide is to be added to these metallic oxides in order to reduce the increase in grain size. (author)

  5. Rapidly curable electrically conductive clear coatings

    Energy Technology Data Exchange (ETDEWEB)

    Bowman, Mark P.; Anderson, Lawrence G.; Post, Gordon L.

    2018-01-16

    Rapidly curable electrically conductive clear coatings are applied to substrates. The electrically conductive clear coating includes to clear layer having a resinous binder with ultrafine non-stoichiometric tungsten oxide particles dispersed therein. The clear coating may be rapidly cured by subjecting the coating to infrared radiation that heats the tungsten oxide particles and surrounding resinous binder. Localized heating increases the temperature of the coating to thereby thermally cure the coating, while avoiding unwanted heating of the underlying substrate.

  6. White coat hypertension in pediatrics.

    Science.gov (United States)

    Jurko, Alexander; Minarik, Milan; Jurko, Tomas; Tonhajzerova, Ingrid

    2016-01-15

    The article summarizes current information on blood pressure changes in children during clinic visit. White coat as a general dressing of physicians and health care personnel has been widely accepted at the end of the 19th century. Two problems can be associated with the use of white coat: white coat phenomenon and white coat hypertension. Children often attribute pain and other unpleasant experience to the white coat and refuse afterwards cooperation with examinations. Definition of white coat hypertension in the literature is not uniform. It has been defined as elevated blood pressure in the hospital or clinic with normal blood pressure at home measured during the day by ambulatory blood pressure monitoring system. White coat effect is defined as temporary increase in blood pressure before and during visit in the clinic, regardless what the average daily ambulatory blood pressure values are. Clinical importance of white coat hypertension is mainly because of higher risk for cardiovascular accidents that are dependent on end organ damage (heart, vessels, kidney). Current data do not allow any clear recommendations for the treatment. Pharmacological therapy is usually started in the presence of hypertrophic left ventricle, changes in intimal/medial wall thickness of carotic arteries, microalbuminuria and other cardiovascular risk factors. Nonpharmacological therapy is less controversial and certainly more appropriate. Patients have to change their life style, need to eliminate as much cardiovascular risk factors as possible and sustain a regular blood pressure monitoring.

  7. External coating of colonic anastomoses

    DEFF Research Database (Denmark)

    Pommergaard, Hans-Christian; Achiam, Michael Patrick; Rosenberg, Jacob

    2012-01-01

    Colon anastomotic leakage remains both a frequent and serious complication in gastrointestinal surgery. External coating of colonic anastomoses has been proposed as a means to lower the rate of this complication. The aim of this review was to evaluate existing studies on external coating of colonic...

  8. Moisture transport in coated wood

    NARCIS (Netherlands)

    Meel, P.A. van; Erich, S.J.F.; Huinink, H.P.; Kopinga, K.; Jong, J. DE; Adan, O.C.G.

    2011-01-01

    Moisture accumulation inside wood causes favorable conditions for decay. Application of a coating alters the moisture sorption of wood and prevents accumulation of moisture. This paper presents the results of a nuclear magnetic resonance (NMR) study on the influence of a coating on the moisture

  9. Electroless alloy/composite coatings

    Indian Academy of Sciences (India)

    The market for these coatings is expanding fast as the potential applications are on the rise. In the present article, an attempt has been made to review different electroless alloy/composite coatings with respect to bath types and their composition, properties and applications. Different characterisation studies have been ...

  10. Lignin based controlled release coatings

    NARCIS (Netherlands)

    Mulder, W.J.; Gosselink, R.J.A.; Vingerhoeds, M.H.; Harmsen, P.F.H.; Eastham, D.

    2011-01-01

    Urea is a commonly used fertilizer. Due to its high water-solubility, misuse easily leads to excess nitrogen levels in the soil. The aim of this research was to develop an economically feasible and biodegradable slow-release coating for urea. For this purpose, lignin was selected as coating

  11. Foundry Coating Technology: A Review

    DEFF Research Database (Denmark)

    Nwaogu, Ugochukwu Chibuzoh; Tiedje, Niels Skat

    2011-01-01

    is important. In this review, a detailed description of these topics and examples are provided where necessary. A potential area of research in foundry coating development, using sol-gel process is suggested. The application of sol-gel technology in the development of foundry coatings is a novel approach....

  12. Intumescent coatings under fast heating

    DEFF Research Database (Denmark)

    Nørgaard, Kristian Petersen; Dam-Johansen, Kim; Català, Pere

    2012-01-01

    Intumescent coatings are widely used to delay or minimise the destructive effects of fire. They are usually tested under conditions that simulate the relatively slow build-up of heat in a normal fire. Here, the effects of damage during a fire causing sudden heating of the coating were studied....

  13. Steam initiated hydrotalcite conversion coatings

    DEFF Research Database (Denmark)

    Zhou, Lingli; Friis, Henrik; Roefzaad, Melanie

    2018-01-01

    A facile process of exploiting high-temperature steam to deposit nvironmentally friendly hydrotalcite (HT) coatings on Al alloy 6060 was developed in a spray system. Scanning electron microscopy showed the formationf a continuous and conformal coating comprised of a compact mass of crystallites. ...

  14. Enteric-coated mycophenolate sodium.

    Science.gov (United States)

    Gabardi, Steven; Tran, Jennifer L; Clarkson, Michael R

    2003-11-01

    To review the pharmacology, pharmacokinetics, efficacy, and safety of mycophenolate sodium. Primary literature was obtained via a MEDLINE search (1966-June 2003). Abstracts were obtained from the manufacturer and included in the analysis. All studies and abstracts evaluating mycophenolate sodium in solid organ transplantation were considered for inclusion. English-language studies and abstracts were selected for inclusion, but were limited to those consisting of human subjects. Mycophenolate sodium, a mycophenolic acid prodrug, is an inhibitor of T-lymphocyte proliferation. Mycophenolic acid reduces the incidence of acute rejection in renal transplantation. Mycophenolate sodium is enteric coated and has been suggested as a potential method to reduce the gastrointestinal adverse events seen with mycophenolate mofetil. Both mycophenolate mofetil and mycophenolate sodium have been shown to be therapeutically equivalent at decreasing the incidence of allograft rejection and loss. The frequency of adverse events is similar between both compounds, with the most common events being diarrhea and leukopenia. Mycophenolate sodium is effective in preventing acute rejection in renal transplant recipients. At doses of 720 mg twice daily, the efficacy and safety profiles are similar to those of mycophenolate mofetil 1000 mg twice daily. Mycophenolate sodium has been approved in Switzerland; approval in the US is pending.

  15. Cell-derived matrix coatings for polymeric scaffolds.

    Science.gov (United States)

    Decaris, Martin L; Binder, Bernard Y; Soicher, Matthew A; Bhat, Archana; Leach, J Kent

    2012-10-01

    Cells in culture deposit a complex extracellular matrix that remains intact following decellularization and possesses the capacity to modulate cell phenotype. The direct application of such decellularized matrices (DMs) to 3D substrates is problematic, as transport issues influence the homogeneous deposition, decellularization, and modification of DM surface coatings. In an attempt to address this shortcoming, we hypothesized that DMs deposited by human mesenchymal stem cells (MSCs) could be transferred to the surface of polymeric scaffolds while maintaining their capacity to direct cell fate. The ability of the transferred DM (tDM)-coated scaffolds to enhance the osteogenic differentiation of undifferentiated and osteogenically induced MSCs under osteogenic conditions in vitro was confirmed. tDM-coated scaffolds increased MSC expression of osteogenic marker genes (BGLAP, IBSP) and intracellular alkaline phosphatase production. In addition, undifferentiated MSCs deposited significantly more calcium when seeded onto tDM-coated scaffolds compared with control scaffolds. MSC-seeded tDM-coated scaffolds subcutaneously implanted in nude rats displayed significantly higher blood vessel density after 2 weeks compared with cells on uncoated scaffolds, but we did not observe significant differences in mineral deposition after 8 weeks. These data demonstrate that DM-coatings produced in 2D culture can be successfully transferred to 3D substrates and retain their capacity to modulate cell phenotype.

  16. Inhibition of Staphylococcus epidermidis Biofilm by Trimethylsilane Plasma Coating

    Science.gov (United States)

    Ma, Yibao; Jones, John E.; Ritts, Andrew C.; Yu, Qingsong

    2012-01-01

    Biofilm formation on implantable medical devices is a major impediment to the treatment of nosocomial infections and promotes local progressive tissue destruction. Staphylococcus epidermidis infections are the leading cause of biofilm formation on indwelling devices. Bacteria in biofilms are highly resistant to antibiotic treatment, which in combination with the increasing prevalence of antibiotic resistance among human pathogens further complicates treatment of biofilm-related device infections. We have developed a novel plasma coating technology. Trimethylsilane (TMS) was used as a monomer to coat the surfaces of 316L stainless steel and grade 5 titanium alloy, which are widely used in implantable medical devices. The results of biofilm assays demonstrated that this TMS coating markedly decreased S. epidermidis biofilm formation by inhibiting the attachment of bacterial cells to the TMS-coated surfaces during the early phase of biofilm development. We also discovered that bacterial cells on the TMS-coated surfaces were more susceptible to antibiotic treatment than their counterparts in biofilms on uncoated surfaces. These findings suggested that TMS coating could result in a surface that is resistant to biofilm development and also in a bacterial community that is more sensitive to antibiotic therapy than typical biofilms. PMID:22964248

  17. Biomimetic calcium phosphate coatings on recombinant spider silk fibres

    Energy Technology Data Exchange (ETDEWEB)

    Yang Liang; Habibovic, Pamela; Van Blitterswijk, Clemens A [Department of Tissue Regeneration, University of Twente, PO Box 217, 7500 AE Enschede (Netherlands); Hedhammar, My; Johansson, Jan [Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, the Biomedical Centre, Box 575, 751 23 Uppsala (Sweden); Blom, Tobias; Leifer, Klaus [Department of Engineering Sciences, Uppsala University, Box 534, S-751 21 Uppsala (Sweden)

    2010-08-01

    Calcium phosphate ceramic coatings, applied on surfaces of metallic and polymeric biomaterials, can improve their performance in bone repair and regeneration. Spider silk is biocompatible, strong and elastic, and hence an attractive biomaterial for applications in connective tissue repair. Recently, artificial spider silk, with mechanical and structural characteristics similar to those of native spider silk, has been produced from recombinant minispidroins. In the present study, supersaturated simulated body fluid was used to deposit calcium phosphate coatings on recombinant spider silk fibres. The mineralization process was followed in time using scanning electron microscopy equipped with an energy dispersive x-ray (EDX) detector and Raman spectroscope. Focused ion beam technology was used to produce a cross section of a coated fibre, which was further analysed by EDX. Preliminary in vitro experiments using a culture of bone marrow-derived human mesenchymal stem cells (hMSCs) on coated fibres were also performed. This study showed that recombinant spider silk fibres were successfully coated with a homogeneous and thick crystalline calcium phosphate layer. In the course of the mineralization process from modified simulated body fluid, sodium chloride crystals were first deposited on the silk surface, followed by the deposition of a calcium phosphate layer. The coated silk fibres supported the attachment and growth of hMSCs.

  18. Biomimetic calcium phosphate coatings on recombinant spider silk fibres

    International Nuclear Information System (INIS)

    Yang Liang; Habibovic, Pamela; Van Blitterswijk, Clemens A; Hedhammar, My; Johansson, Jan; Blom, Tobias; Leifer, Klaus

    2010-01-01

    Calcium phosphate ceramic coatings, applied on surfaces of metallic and polymeric biomaterials, can improve their performance in bone repair and regeneration. Spider silk is biocompatible, strong and elastic, and hence an attractive biomaterial for applications in connective tissue repair. Recently, artificial spider silk, with mechanical and structural characteristics similar to those of native spider silk, has been produced from recombinant minispidroins. In the present study, supersaturated simulated body fluid was used to deposit calcium phosphate coatings on recombinant spider silk fibres. The mineralization process was followed in time using scanning electron microscopy equipped with an energy dispersive x-ray (EDX) detector and Raman spectroscope. Focused ion beam technology was used to produce a cross section of a coated fibre, which was further analysed by EDX. Preliminary in vitro experiments using a culture of bone marrow-derived human mesenchymal stem cells (hMSCs) on coated fibres were also performed. This study showed that recombinant spider silk fibres were successfully coated with a homogeneous and thick crystalline calcium phosphate layer. In the course of the mineralization process from modified simulated body fluid, sodium chloride crystals were first deposited on the silk surface, followed by the deposition of a calcium phosphate layer. The coated silk fibres supported the attachment and growth of hMSCs.

  19. Neocellularization and neovascularization of nanosized bioactive glass-coated decellularized trabecular bone scaffolds

    KAUST Repository

    Gerhardt, Lutz Christian

    2012-09-11

    In this study, the in vivo recellularization and neovascularization of nanosized bioactive glass (n-BG)-coated decellu-larized trabecular bone scaffolds were studied in a rat model and quantified using stereological analyses. Based on the highest amount of vascular endothelial growth factor (VEGF) secreted by human fibroblasts grown on n-BG coatings (0-1.245 mg/cm 2), decellularized trabecular bone samples (porosity: 43-81%) were coated with n-BG particles. Grown on n-BG particles at a coating density of 0.263 mg/cm2, human fibroblasts produced 4.3 times more VEGF than on uncoated controls. After 8 weeks of implantation in Sprague-Dawley rats, both uncoated and n-BG-coated samples were well infiltrated with newly formed tissue (47-48%) and blood vessels (3-4%). No significant differences were found in cellularization and vascularization between uncoated bone scaffolds and n-BG-coated scaffolds. This finding indicates that the decellularized bone itself may exhibit growth-promoting properties induced by the highly interconnected pore microarchitecture and/or proteins left behind on decellularized scaffolds. Even if we did not find proangiogenic effects in n-BG-coated bone scaffolds, a bioactive coating is considered to be beneficial to impart osteoinductive and osteoconductive properties to decellularized bone. n-BG-coated bone grafts have thus high clinical potential for the regeneration of complex tissue defects given their ability for recellularization and neovascularization. © 2012 Wiley Periodicals, Inc.

  20. Evanescent wave assisted nanomaterial coating.

    Science.gov (United States)

    Mondal, Samir K; Pal, Sudipta Sarkar; Kumbhakar, Dharmadas; Tiwari, Umesh; Bhatnagar, Randhir

    2013-08-01

    In this work we present a novel nanomaterial coating technique using evanescent wave (EW). The gradient force in the EW is used as an optical tweezer for tweezing and self-assembling nanoparticles on the source of EW. As a proof of the concept, we have used a laser coupled etched multimode optical fiber, which generates EW for the EW assisted coating. The section-wise etched multimode optical fiber is horizontally and superficially dipped into a silver/gold nanoparticles solution while the laser is switched on. The fiber is left until the solution recedes due to evaporation leaving the fiber in air. The coating time usually takes 40-50 min at room temperature. The scanning electron microscope image shows uniform and thin coating of self-assembled nanoparticles due to EW around the etched section. A coating thickness optical fiber probes and other plasmonic circuits.

  1. Functional Plasma-Deposited Coatings

    Directory of Open Access Journals (Sweden)

    Mykhaylo Pashechko

    2017-12-01

    Full Text Available The paper focuses on the problem of low adhesion of plasma sprayed coatings to the substrate. The subsequent laser treatment modes and their influence on the coating-substrate interface were studied. This allows to decrease the level of metstability of the coating, thus decreasing its hardness down to 11-12 GPa on the surface and to about 9 GPa on depth of 400 µm. The redistribution of alloying elements through solid and liquid diffusion improves mechanical properties and rises the adhesion up to 450 MPa after remelting and up to 90-110 MPa after laser-aided thermal cycling. At he same time, remelting of coating helps to decrease its porosity down to 1%. Obtained complex of properties also allows to improve wear resistance of coatings and to decrease friction factor.

  2. Self-Healing anticorrosive coatings

    DEFF Research Database (Denmark)

    Nesterova, Tatyana

    %. The number is lower than anticipated and needs to be confirmed. Finally, a 3-D model, based on Monte-Carlo simulations, has been developed for prediction of healing efficiency of a microcapsule-based anticorrosive coating. Two kinds of cracks were considered: cracks accommodated within the bulk coating...... associated with development and testing of this type of coating. A laboratory investigation, to identify the most suitable method for production of mechanically stable (filled with industrially relevant core materials) and forming a free-flowing powder upon drying microcapsules, has been performed. Four...... reduces the intensity of crack formation (both in number and length) compared to filler-containing coatings and prevents the coating from flaking upon damage. Based on specular gloss measurements, a preliminary critical pigment (microcapsule) concentration (CPVC) value was estimated to about 30 vol...

  3. Carbon nanotube-coating accelerated cell adhesion and proliferation on poly (L-lactide)

    Science.gov (United States)

    Hirata, Eri; Akasaka, Tsukasa; Uo, Motohiro; Takita, Hiroko; Watari, Fumio; Yokoyama, Atsuro

    2012-12-01

    The surface of a polylactic acid (PLLA) was coated multiwalled carbon nanotubes (MWCNTs) in order to improve the surface properties. In addition, its surface characteristics and cell culturing properties were examined. Whole surface of PLLA was homogeneously covered by MWCNTs maintained a unique tubular structure. MWCNT-coated PLLA showed remarkable higher wettability than uncoated PLLA. Human osteosarcoma cell line (Saos2) adhered well on the CNT-coated PLLA whereas there are few cells attached on the uncoated PLLA at 2 h after seeding. The number of the cells on uncoated PLLA was still smaller than on the MWCNT-coated PLLA at 1 and 3 days. Moreover, The DNA content in the cells attached to the MWCNT-coated PLLA was significantly higher than that on the uncoated PLLA (p 0.1). Therefore MWCNT-coating on PLLA improved the surface wettability and initial cell attachment at early stage.

  4. Development of Ceramic Coating on Metal Substrate using Industrial Waste and Ore Minerals

    Science.gov (United States)

    Bhuyan, S. K.; Thiyagarajan, T. K.; Mishra, S. C.

    2017-02-01

    The technological advancement in modern era has a boon for enlightening human life; but also is a bane to produce a huge amount of (industrial) wastes, which is of great concern for utilization and not to create environmental threats viz. polution etc. In the present piece of research work, attempts have been made to utilize fly ash (wastes of thermal power plants) and along with alumina bearing ore i.e. bauxite, for developing plasma spray ceramic coatings on metals. Fly ash and with 10 and 20% bauxite addition is used to deposit plasma spray coatings on a metal substrate. The surface morphology of the coatings deposited at different power levels of plasma spraying investigated through SEM and EDS analysis. The coating thickness is measured. The porosity levels of the coatings are evaluated. The coating hardness isalso measured. This piece of research work will be beneficial for future development and use of industrial waste and ore minerals for high-valued applications.

  5. Preparation and mechanism analysis of an environment-friendly maize seed coating agent.

    Science.gov (United States)

    Zeng, Defang; Fan, Zhao; Tian, Xu; Wang, Wenjin; Zhou, Mingchun; Li, Haochuan

    2018-06-01

    Traditional seed coating agents often contain toxic ingredients, which contaminate the environment and threaten human health. This paper expounds a method of preparing a novel environment-friendly seed coating agent for maize and researches its mechanism of action. The natural polysaccharide polymer, which is the main active ingredient of this environment-friendly seed coating agent, has the characteristics of innocuity and harmlessness, and it can replace the toxic ingredients used in traditional seed coating agents. This environment-friendly seed coating agent for maize was mainly made up of the natural polysaccharide polymer and other additives. The field trials results showed that the control efficacy of Helminthosporium maydis came to 93.72%, the anti-feeding rate of cutworms came to 81.29%, and the maize yield was increased by 17.75%. Besides, the LD 50 value (half the lethal dose in rats) of this seed coating agent was 10 times higher than that of the traditional seed coating agents. This seed coating agent could improve the activity of plant protective enzymes (peroxidase, catalase and superoxidase dismutase) and increase the chlorophyll content. This seed coating agent has four characteristics of disease prevention, desinsectization, increasing yield and safety. Results of mechanism analyses showed that this seed coating agent could enhance disease control effectiveness by improving plant protective enzymes activity and increase maize yield by improving chlorophyll content. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  6. Understanding particulate coating microstructure development

    Science.gov (United States)

    Roberts, Christine Cardinal

    How a dispersion of particulates suspended in a solvent dries into a solid coating often is more important to the final coating quality than even its composition. Essential properties like porosity, strength, gloss, particulate order, and concentration gradients are all determined by the way the particles come together as the coating dries. Cryogenic scanning electron microscopy (cryoSEM) is one of the most effective methods to directly visualize a drying coating during film formation. Using this method, the coating is frozen, arresting particulate motion and solidifying the sample so that it be imaged in an SEM. In this thesis, the microstructure development of particulate coatings was explored with several case studies. First, the effect of drying conditions was determined on the collapse of hollow latex particles, which are inexpensive whiteners for paint. Using cryoSEM, it was found that collapse occurs during the last stages of drying and is most likely to occur at high drying temperatures, humidity, and with low binder concentration. From these results, a theoretical model was proposed for the collapse of a hollow latex particle. CryoSEM was also used to verify a theoretical model for the particulate concentration gradients that may develop in a coating during drying for various evaporation, sedimentation and particulate diffusion rates. This work created a simple drying map that will allow others to predict the character of a drying coating based on easily calculable parameters. Finally, the effect of temperature on the coalescence and cracking of latex coatings was explored. A new drying regime for latex coatings was identified, where partial coalescence of particles does not prevent cracking. Silica was shown to be an environmentally friendly additive for preventing crack formation in this regime.

  7. Gelatin methacrylamide as coating material in cell culture.

    Science.gov (United States)

    Egger, Michael; Tovar, Günter E M; Hoch, Eva; Southan, Alexander

    2016-06-13

    Unmodified gelatin (uG) is widely used as a coating material in cell culture for improving surface properties. In this study, the authors investigated if gelatin methacrylamide (GM) with a medium degree of methacrylamide modification (GM1.5) and a high degree of methacrylamide modification (GM4) are equally suitable for this purpose. Therefore, gold surfaces were coated with uG, GM1.5, and GM4 by adsorption of the polymers on the surfaces. Coating success was confirmed by spectroscopic ellipsometry, contact angle measurements, surface plasmon resonance spectroscopy (SPRS), and atomic force microscopy (AFM). The authors found that upon adsorption of uG, GM1.5, a nd GM4 on gold, thin films with thicknesses of 2.95 nm, 2.50 nm, and 2.26 nm were formed. The coated surfaces showed advancing contact angles of 46° (uG and GM1.5) and 52° (GM4) without alteration of the surface roughness determined by AFM. Protein adsorption taking place on the coated surfaces was measured during contact of the surfaces with fetal calf serum by SPRS. Protein adsorption on the coated surfaces was reduced by the factor of 6.4 (uG), 5.4 (GM1.5), and 4.6 (GM4) compared to gold surfaces. Human fibroblasts cultured on the surfaces showed excellent viability shown by water soluble tetrazolium salt assay as well as live/dead staining with propidium iodide and fluorescein diacetate. No cytotoxic effects of the GM coated surfaces were observed, giving rise to the conclusion that GMs are suitable materials as coatings in cell culture.

  8. An update on coating/manufacturing techniques of microneedles.

    Science.gov (United States)

    Tarbox, Tamara N; Watts, Alan B; Cui, Zhengrong; Williams, Robert O

    2017-12-29

    Recently, results have been published for the first successful phase I human clinical trial investigating the use of dissolving polymeric microneedles… Even so, further clinical development represents an important hurdle that remains in the translation of microneedle technology to approved products. Specifically, the potential for accumulation of polymer within the skin upon repeated application of dissolving and coated microneedles, combined with a lack of safety data in humans, predicates a need for further clinical investigation. Polymers are an important consideration for microneedle technology-from both manufacturing and drug delivery perspectives. The use of polymers enables a tunable delivery strategy, but the scalability of conventional manufacturing techniques could arguably benefit from further optimization. Micromolding has been suggested in the literature as a commercially viable means to mass production of both dissolving and swellable microneedles. However, the reliance on master molds, which are commonly manufactured using resource intensive microelectronics industry-derived processes, imparts notable material and design limitations. Further, the inherently multi-step filling and handling processes associated with micromolding are typically batch processes, which can be challenging to scale up. Similarly, conventional microneedle coating processes often follow step-wise batch processing. Recent developments in microneedle coating and manufacturing techniques are highlighted, including micromilling, atomized spraying, inkjet printing, drawing lithography, droplet-born air blowing, electro-drawing, continuous liquid interface production, 3D printing, and polyelectrolyte multilayer coating. This review provides an analysis of papers reporting on potentially scalable production techniques for the coating and manufacturing of microneedles.

  9. Optical coating preparation

    International Nuclear Information System (INIS)

    Belleville, P.; Sabary, F.; Marcel, C.

    2003-01-01

    In order to optimize the properties of optical components, thin film deposition with controlled thickness and refractive index is often needed. Two different deposition techniques are proposed in this article and illustrated with examples: physical vapor deposition (PVD) and liquid sol-gel process (LSG). PVD and LSG techniques are equivalent as far as the following topics are concerned: elaboration of oxide or composite coated material, optical performance, mechanical performance, and laser performance. PVD is better for the elaboration of metallic films, the design of multi-layers or complex pile-up of layers. LSG is better for the treatment of large surfaces, for substrates with complicated shapes and for its low cost. PVD technique has been widely used so it benefited from an industrial maturity and a clean technology concerning wastes and effluents. On the contrary LSG is a new technique not yet widely used in industrial processes but that looks promising. (A.C.)

  10. Novel coating compositions

    International Nuclear Information System (INIS)

    Kimura, Tadashi; Kobayashi, Juichi; Nakamoto, Hideo.

    1969-01-01

    An acrylic coating composition rapidly hardenable by irradiating with ionizing radiations or light beams is given using hydroxyl group-containing vinyl monomers, polycarboxylic acid anhydrides, epoxy group-containing vinyl monomers and an organic solvent having a boiling point of at least 120 0 C. The process comprises the steps of first and second reactions. The first reaction takes place between one mol of a hydroxyl group of a basic polymer and at least 0.1 mol of polycarboxylic acid anhydride, wherein the basic polymer has a molecular weight ranging from 5,000 to 100,000 and consists of 1-40% by weight of vinyl monomer containing hydroxyl group, at least 30% of (meth)acrylic monomer and other vinyl monomers if required. The second reaction takes place between one mol of hydroxyl plus a carboxyl group of the thus obtained basic polymer and at least 0.1 mol of an epoxy group-containing vinyl monomer to produce a prepolymer. The prepolymer is mixed with a solvent such as ethyl benzene to produce the coating material. The electron beam accelerator energy level may be 0.1-2.0 MeV. In light beam polymerization, benzoin is particularly utilized as an intensifying substance. In one example, a basic polymer is produced by reacting 39 parts of styrene, 37 parts of ethyl acrylate, 24 parts of 2-hydroxyl ethyl acrylate, 4 parts of dimethyl amino ethyl methacrylate and others. A prepolymer is produced by reacting this basic polymer with 30 parts of glycidyl acrylate and others. (Iwakiri, K.)

  11. How PE tape performs under concrete coating

    International Nuclear Information System (INIS)

    Dritt, H.J.

    1984-01-01

    The program objectives were to evaluate the performance of polyethylene tape plant coating and fusion bonded epoxy powder systems with particular respect to the following: 1. Concrete coating application procedures; 2. The shear resistance during laying and retrieving operations of the coating at the various interfaces (a) Pipe and anti-corrosion coating; (b) Anti-corrosion coating and outerwrap; (c) Overlap areas of the anti-corrosion and outerwrap layers; (d) Between concrete and the various corrosion coatings during laying and retrieving operations. 3. Resistance to damage of the coating as a consequence of cracking or slippage of the concrete weight coating. 4. Ability of various coatings to withstand the damage during concrete application by both impact and compression methods; 5. Evaluation of tape and shrink sleeve joint coatings at the cut-back area as well as performance of tape under hot asphalt coating

  12. Antibacterial properties and cytocompatibility of tantalum oxide coatings with different silver content

    International Nuclear Information System (INIS)

    Huang, Heng-Li; Chang, Yin-Yu; Chen, Hung-Jui; Chou, Yu-Kai; Lai, Chih-Ho; Chen, Michael Y. C.

    2014-01-01

    Tantalum (Ta) oxides and their coatings have been proved to increase their applications in the biomedical fields by improving osseointegration and wear resistance. In this study, Ta oxide coatings containing different proportions of Ag are deposited on SS304 materials. A twin-gun magnetron sputtering system is used to deposit the tantalum oxide-Ag coating. In this study, Staphylococcus aureus, which exhibits physiological commensalism on the human skin, nares, and mucosal and oral areas, is chosen as the model for in vitro antibacterial analyses via a fluorescence staining method using Syto9. The cytocompatibility and adhesive morphology of human skin fibroblast cells (CCD-966SK) on the coatings are also determined by using the microculture tetrazolium assay. This study shows that Ta 2 O 5 and Ta 2 O 5 -Ag coatings with 12.5 at. % of Ag exhibit improved antibacterial effects against S. aureus and have good skin fibroblast cell cellular biocompatibility

  13. Electrochemically assisted co-deposition of calcium phosphate/collagen coatings on carbon/carbon composites

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Xueni [C/C Composites Technology Research Center, State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi' an, Shaanxi 710072 (China); Hu Tao [C/C Composites Technology Research Center, State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi' an, Shaanxi 710072 (China); Department of Cardiology, Xijing Hospital, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China); Li Hejun, E-mail: lihejun@nwpu.edu.cn [C/C Composites Technology Research Center, State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi' an, Shaanxi 710072 (China); Chen Mengdi; Cao Sheng; Zhang Leilei [C/C Composites Technology Research Center, State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi' an, Shaanxi 710072 (China); Hou Xianghui [Department of Mechanical, Materials and Manufacturing Engineering, University of Nottingham, University Park, Nottingham NG7 2RD (United Kingdom)

    2011-02-01

    Calcium phosphate (CaP)/collagen coatings were prepared on the surface of carbon/carbon (C/C) composites by electrochemically assisted co-deposition technique. The effects of collagen concentration in the electrolyte on morphology, structure and composition of the coatings were systematically investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transformed infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). The adhesive strength of the coatings was also evaluated by scratch tests and tensile bond tests. It was demonstrated that the coatings of three-dimensional collagen network structure was formed on the C/C composites from the electrolyte containing collagen. The surface of the collagen network was covered by uniform CaP aggregates. The coatings were actually composites of CaP and collagen. Hydroxyapatite (HA) was a favorable composition in the coatings with the increase of the collagen concentration in the electrolyte. The formed collagen network increased the cohesive and adhesive strength of the coatings. The adhesive strength between the coatings and substrates increased as the collagen concentration in the electrolyte increased. The coatings prepared at the collagen concentration of 500 mg/L in the electrolyte were not scraped off until the applied load reached 32.0 {+-} 2.2 N and the average tensile adhesive strength of the coatings was 4.83 {+-} 0.71 MPa. After C/C coated with composite coatings (500 mg/L) being immersed in a 10{sup -3} M Ca (OH){sub 2} solution at 30-33 deg. C for 96 h, nano-structured HA/collagen coatings similar to the natural human bone were obtained on the C/C.

  14. Preparation and properties of in-situ growth of carbon nanotubes reinforced hydroxyapatite coating for carbon/carbon composites

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Shoujie, E-mail: jlliushoujie@126.com; Li, Hejun, E-mail: lihejun@nwpu.edu.cn; Su, Yangyang, E-mail: suyangyang@mail.nwpu.edu.cn; Guo, Qian, E-mail: 1729299905@163.com; Zhang, Leilei, E-mail: zhangleilei@nwpu.edu.cn

    2017-01-01

    Carbon nanotubes (CNTs) possess excellent mechanical properties for their role playing in reinforcement as imparting strength to brittle hydroxyapatite (HA) bioceramic coating. However, there are few reports relating to the in-situ grown carbon nanotubes reinforced hydroxyapatite (CNTs-HA) coating. Here we demonstrate the potential application in reinforcing biomaterials by an attempt to use in-situ grown of CNTs strengthen HA coating, using a combined method composited of injection chemical vapor deposition (ICVD) and pulsed electrodeposition. The microstructure, phases and chemical compositions of CNTs-HA coatings were characterized by various advanced methods. The scanning electron microscopy (SEM) images indicated that CNTs-HA coatings avoided the inhomogeneous dispersion of CNTs inside HA coating. The result show that the interfacial shear strength between CNTs-HA coating and the C/C composite matrix reaches to 12.86 ± 1.43 MPa. Potenitodynamic polarization and electrochemical impedance spectroscopy (EIS) studies show that the content of CNTs affects the corrosion resistance of CNTs-HA coating. Cell culturing and simulated body fluid test elicit the biocompatibility with living cells and bioactivity of CNTs-HA coatings, respectively. - Highlights: • A novel bioceramic composite coating of hydroxyapatite reinforced with in-situ grown carbon nanotubes was fabricated. • The doping of carbon nanotubes had almost no impact on the biocompatibility of hydroxyapatite coatings. • The doping of carbon nanotubes improved corrosion resistance of hydroxyapatite coatings in simulated human body solution.

  15. Avian Egg and Egg Coat.

    Science.gov (United States)

    Okumura, Hiroki

    2017-01-01

    An ovulated egg of vertebrates is surrounded by unique extracellular matrix, the egg coat or zona pellucida, playing important roles in fertilization and early development. The vertebrate egg coat is composed of two to six zona pellucida (ZP) glycoproteins that are characterized by the evolutionarily conserved ZP-domain module and classified into six subfamilies based on phylogenetic analyses. Interestingly, investigations of biochemical and functional features of the ZP glycoproteins show that the roles of each ZP-glycoprotein family member in the egg-coat formation and the egg-sperm interactions seemingly vary across vertebrates. This might be one reason why comprehensive understandings of the molecular basis of either architecture or physiological functions of egg coat still remain elusive despite more than 3 decades of intensive investigations. In this chapter, an overview of avian egg focusing on the oogenesis are provided in the first section, and unique features of avian egg coat, i.e., perivitelline layer, including the morphology, biogenesis pathway, and physiological functions are discussed mainly on chicken and quail in terms of the characteristics of ZP glycoproteins in the following sections. In addition, these features of avian egg coat are compared to mammalian zona pellucida, from the viewpoint that the structural and functional varieties of ZP glycoproteins might be associated with the evolutionary adaptation to their reproductive strategies. By comparing the egg coat of birds and mammals whose reproductive strategies are largely different, new insights into the molecular mechanisms of vertebrate egg-sperm interactions might be provided.

  16. The Relationship Between Coat Color and Aggressive Behaviors in the Domestic Cat

    OpenAIRE

    Stelow, EA; Bain, MJ; Kass, PH

    2015-01-01

    © 2016 Taylor & Francis. The authors explored a possible relationship between coat color and aggressive behaviors in the domestic cat. This study used an Internet-based survey to collect information on coat color, affiliative behaviors toward cats/humans, agonistic behaviors toward cats/humans, other “problem” behaviors, and cat and guardian demographic data. A total of 1,432 cat guardians completed the online survey; after exclusions based on study protocol, data analysis included 1,274 co...

  17. Intumescent Coatings as Fire Retardants

    Science.gov (United States)

    Parker, J. A.; Fohlen, G. M.; Sawko, P. M.; Fish, R. H.

    1970-01-01

    The development of fire-retardant coatings to protect surfaces which may be exposed to fire or extreme heat is a subject of intense interest to many industries. A fire-retardant paint has been developed which represents a new chemical approach for preparing intumescent coatings, and potentially, is very important to fire-prevention authorities. The requirements for a superior coating include ease of application, suitability to a wide variety of surfaces and finishes, and stability over an extended period of time within a broad range of ambient temperature and humidity conditions. These innovative coatings, when activated by the heat of a fire, react to form a thick, low-density, polymeric coating or char layer. Water vapor and sulphur dioxide are released during the intumescent reaction. Two fire-protection mechanisms thus become available: (1) the char layer retards the flow of heat, due to the extremely low thermal conductivity; and (2) water vapor and sulfur dioxide are released, providing fire quenching properties. Still another mechanism functions in cases where the char, by virtue of its high oxidation resistance and low thermal conductivity, reaches a sufficiently high temperature to re-radiate much of the incident heat load. The coatings consist of dispersions of selective salts of a nitro-amino-arornatic compound. Specifically, para-nitroaniline bisulfate and the ammonium salt of para-nitroaniline-ortho sulphuric acid (2-amino-5-nitrobenzenesulphuric acid) are used. Suitable vehicles are cellulose nitrate of lacquer grade, a nitrite-phenolic modified rubber, or epoxy-polysulfide copolymer. Three separate formulations have been developed. A solvent is usually employed, such as methylethyl ketone, butyl acetate, or toluene, which renders the coatings suitably thin and which evaporates after the coatings are applied. Generally, the intumescent material is treated as insoluble in the vehicle, and is ground and dispersed in the vehicle and solvent like an

  18. Integrated Glass Coating Manufacturing Line

    Energy Technology Data Exchange (ETDEWEB)

    Brophy, Brenor [Enki Technology Inc., San Jose, CA (United States)

    2015-09-30

    This project aims to enable US module manufacturers to coat glass with Enki’s state of the art tunable functionalized AR coatings at the lowest possible cost and highest possible performance by encapsulating Enki’s coating process in an integrated tool that facilitates effective process improvement through metrology and data analysis for greater quality and performance while reducing footprint, operating and capital costs. The Phase 1 objective was a fully designed manufacturing line, including fully specified equipment ready for issue of purchase requisitions; a detailed economic justification based on market prices at the end of Phase 1 and projected manufacturing costs and a detailed deployment plan for the equipment.

  19. Laser-based coatings removal

    International Nuclear Information System (INIS)

    Freiwald, J.G.; Freiwald, D.A.

    1995-01-01

    Over the years as building and equipment surfaces became contaminated with low levels of uranium or plutonium dust, coats of paint were applied to stabilize the contaminants in place. Most of the earlier paint used was lead-based paint. More recently, various non-lead-based paints, such as two-part epoxy, are used. For D ampersand D (decontamination and decommissioning), it is desirable to remove the paints or other coatings rather than having to tear down and dispose of the entire building. This report describes the use of pulse-repetetion laser systems for the removal of paints and coatings

  20. Hydrogen permeation resistant phosphate coatings

    International Nuclear Information System (INIS)

    McGuire, J.C.

    1979-01-01

    A method for reducing hydrogen diffusion through metal wherein the metal is coated with a phosphate-radical-containing, phosphate-glass-forming material on at least one surface thereof. The coating is then heated to at least 350 0 C to form a phosphate glass. This method is especially applicable to nuclear reactors to minimize tritium diffusion. The coating is preferably formed with a solution of phosphoric acid which may also contain compounds such as MnSO 4 , SiO 2 and Na 2 Cr 2 0 7 . (author)

  1. Hydrogen permeation resistant phosphate coatings

    International Nuclear Information System (INIS)

    McGuire, J.C.

    1979-01-01

    A method for reducing hydrogen diffusion through metal is described. The metal is coated with a phosphate-radical-containing, phosphate-glass-forming material on at least one surface. The coating is then heated to at least 350 0 C to form a phosphate glass. This method is especially applicable to nuclear reactors to minimize tritium diffusion. The coating is preferably formed with a solution of phosphoric acid which may also contain compounds such as MnSO 4 , SiO 2 and Na 2 Cr 2 O 7 . (author)

  2. Laser-based coatings removal

    Energy Technology Data Exchange (ETDEWEB)

    Freiwald, J.G.; Freiwald, D.A. [F2 Associates, Inc., Albuquerque, NM (United States)

    1995-10-01

    Over the years as building and equipment surfaces became contaminated with low levels of uranium or plutonium dust, coats of paint were applied to stabilize the contaminants in place. Most of the earlier paint used was lead-based paint. More recently, various non-lead-based paints, such as two-part epoxy, are used. For D&D (decontamination and decommissioning), it is desirable to remove the paints or other coatings rather than having to tear down and dispose of the entire building. This report describes the use of pulse-repetetion laser systems for the removal of paints and coatings.

  3. Experimental evaluation of coating delamination in vinyl coated metal forming

    International Nuclear Information System (INIS)

    Son, Young Ki; Lee, Chan Joo; Kim, Byung Min; Lee, Jung Min; Byoen, Sang Doek; Lee, Soen Bong

    2012-01-01

    In this paper, a new evaluation and prediction method for coating delamination during sheet metal forming is presented. On the basis of the forming limit diagram (FLD), the current study evaluates the delamination of PET coating by using a cross cut specimen, dome test, and rectangular cup drawing test. Dome test specimens were subjected to biaxial, plane strain, and uniaxial deformation modes. Rectangular cup drawing test specimens were subjected to the deep drawing deformation mode, and compression deformation mode. A vinyl coated metal (VCM) sheet consists of three layers of polymer on the sheet metals: a protective film, a PET layer and a PVC layer. The areas with coating delamination were identified, and the results of the evaluation were plotted according to major and minor strain values, depicting coating delamination. The constructed delamination limit diagram (DLD) can be used to determine the forming limit of VCM during the complex press forming process. ARGUS (GOM) was employed to identify the strain value and deformation mode of the delaminated surface after the press forming. After identifying the areas of delamination, the DLD of the PET coating can be constructed in a format similar to that of the FLD. The forming limit of the VCM sheet can be evaluated using the superimposition of the delamination limit strain of the coating onto the FLD of VCM sheet. The experimental results showed that the proposed test method will support the sheet metal forming process design for VCM sheets. The assessment method presented in this study can be used to determine the delamination limit strain under plastic deformation of other polymer coated metals. The experimental results suggested that the proposed testing method is effective in evaluating delamination for specific applications

  4. Experimental evaluation of coating delamination in vinyl coated metal forming

    Energy Technology Data Exchange (ETDEWEB)

    Son, Young Ki; Lee, Chan Joo; Kim, Byung Min [Pusan National Univ., Busan (Korea, Republic of); Lee, Jung Min [Korea Institute of Industrial Technology, Busan (Korea, Republic of); Byoen, Sang Doek [HA Digital Engineering Gr., Seongsan Gu (Korea, Republic of); Lee, Soen Bong [Keimyung Univ., Daegu (Korea, Republic of)

    2012-10-15

    In this paper, a new evaluation and prediction method for coating delamination during sheet metal forming is presented. On the basis of the forming limit diagram (FLD), the current study evaluates the delamination of PET coating by using a cross cut specimen, dome test, and rectangular cup drawing test. Dome test specimens were subjected to biaxial, plane strain, and uniaxial deformation modes. Rectangular cup drawing test specimens were subjected to the deep drawing deformation mode, and compression deformation mode. A vinyl coated metal (VCM) sheet consists of three layers of polymer on the sheet metals: a protective film, a PET layer and a PVC layer. The areas with coating delamination were identified, and the results of the evaluation were plotted according to major and minor strain values, depicting coating delamination. The constructed delamination limit diagram (DLD) can be used to determine the forming limit of VCM during the complex press forming process. ARGUS (GOM) was employed to identify the strain value and deformation mode of the delaminated surface after the press forming. After identifying the areas of delamination, the DLD of the PET coating can be constructed in a format similar to that of the FLD. The forming limit of the VCM sheet can be evaluated using the superimposition of the delamination limit strain of the coating onto the FLD of VCM sheet. The experimental results showed that the proposed test method will support the sheet metal forming process design for VCM sheets. The assessment method presented in this study can be used to determine the delamination limit strain under plastic deformation of other polymer coated metals. The experimental results suggested that the proposed testing method is effective in evaluating delamination for specific applications.

  5. Water permeability of pigmented waterborne coatings

    NARCIS (Netherlands)

    Donkers, P.A.J.; Huinink, H.P.; Erich, S.J.F.; Reuvers, N.J.W.; Adan, O.C.G.

    2013-01-01

    Coatings are used in a variety of applications. Last decades more and more coating systems are transforming from solvent to waterborne coating systems. In this study the influence of pigments on the water permeability of a waterborne coating system is studied, with special interest in the possible

  6. Radiation cured coatings for fiber optics

    International Nuclear Information System (INIS)

    Ketley, A.D.; Morgan, C.R.

    1978-01-01

    A continuous protective coating is formed on a fiber optic by coating the fiber optic in a bath of a liquid radiation curable composition at a temperature up to 90 0 C and exposing the coated conductor to ultraviolet or high energy ionizing radiation to cure the coating

  7. Hex Chrome Free Coatings for Electronics Overview

    Science.gov (United States)

    Kessel, Kurt

    2013-01-01

    The overall objective of the Hex Chrome Free Coatings for Electronics project is to evaluate and test pretreatment coating systems not containing hexavalent chrome in avionics and electronics housing applications. This objective will be accomplished by testing strong performing coating systems from prior NASA and DoD testing or new coating systems as determined by the stakeholders.

  8. Comparison of additive amount used in spin-coated and roll-coated organic solar cells

    DEFF Research Database (Denmark)

    Cheng, Pei; Lin, Yuze; Zawacka, Natalia Klaudia

    2014-01-01

    All-polymer and polymer/fullerene inverted solar cells were fabricated by spin-coating and roll-coating processes. The spin-coated small-area (0.04 cm(2)) devices were fabricated on indium tin oxide (ITO) coated glass substrates in nitrogen. The roll-coated large-area (1.0 cm(2)) devices were...

  9. Overlay metallic-cermet alloy coating systems

    International Nuclear Information System (INIS)

    Gedwill, M.A.; Glasgow, T.K.; Levine, S.R.

    1982-01-01

    A substrate, such as a turbine blade, vane, or the like, which is subjected to high temperature use is coated with a base coating of an oxide dispersed, metallic alloy (cermet). A top coating of an oxidation, hot corrosion, erosion resistant alloy of nickel, cobalt, or iron is then deposited on the base coating. A heat treatment is used to improve the bonding. The base coating serves as an inhibitor to interdiffusion between the protective top coating and the substrate. Otherwise, the protective top coating would rapidly interact detrimentally with the substrate and degrade by spalling of the protective oxides formed on the outer surface at elevated temperatures

  10. Overlay metallic-cermet alloy coating systems

    Science.gov (United States)

    Gedwill, M. A.; Levine, S. R.; Glasgow, T. K. (Inventor)

    1984-01-01

    A substrate, such as a turbine blade, vane, or the like, which is subjected to high temperature use is coated with a base coating of an oxide dispersed, metallic alloy (cermet). A top coating of an oxidation, hot corrosion, erosion resistant alloy of nickel, cobalt, or iron is then deposited on the base coating. A heat treatment is used to improve the bonding. The base coating serves as an inhibitor to interdiffusion between the protective top coating and the substrate. Otherwise, the protective top coating would rapidly interact detrimentally with the substrate and degrade by spalling of the protective oxides formed on the outer surface at elevated temperatures.

  11. Seal coat binder performance specifications.

    Science.gov (United States)

    2013-11-01

    Need to improve seal coat binder specs: replace empirical tests (penetration, ductility) with : performance-related tests applicable to both : unmodified and modified binders; consider temperatures that cover entire in service : range that are tied t...

  12. Protective coatings for commercial particulates

    DEFF Research Database (Denmark)

    Kindl, B.; Teng, Y.H.; Liu, Y.L.

    1994-01-01

    SiC/Al composites are in large-scale production with Al-Si alloy matrices. The same composites with pure Al or low Si matrices need diffusion barriers on the SiC reinforcement to control the interfacial reaction. The present paper describes various approaches taken to obtain protective coatings...... of alumina and zirconia on SiC particulates by sol-gel techniques. Aqueous and organic precursors have been used. The extent of the reaction, i.e., the Si and Al4C3 content in the matrix, was determined by differential thermal analysis and X-ray diffraction. The reaction rates of some coated particulates...... in liquid Al are decreased by as much as one order of magnitude during the first 15 min of immersion. Pretreatments of the SiC surface, the composition and thickness of the coating interphase and heat treatments of the coated materials have been studied, and are discussed in relation to their effect...

  13. Cementless Hydroxyapatite Coated Hip Prostheses

    Science.gov (United States)

    Herrera, Antonio; Mateo, Jesús; Gil-Albarova, Jorge; Lobo-Escolar, Antonio; Ibarz, Elena; Gabarre, Sergio; Más, Yolanda

    2015-01-01

    More than twenty years ago, hydroxyapatite (HA), calcium phosphate ceramics, was introduced as a coating for cementless hip prostheses. The choice of this ceramic is due to its composition being similar to organic apatite bone crystals. This ceramic is biocompatible, bioactive, and osteoconductive. These qualities facilitate the primary stability and osseointegration of implants. Our surgical experience includes the implantation of more than 4,000 cementless hydroxyapatite coated hip prostheses since 1990. The models implanted are coated with HA in the acetabulum and in the metaphyseal area of the stem. The results corresponding to survival and stability of implants were very satisfactory in the long-term. From our experience, HA-coated hip implants are a reliable alternative which can achieve long term survival, provided that certain requirements are met: good design selection, sound choice of bearing surfaces based on patient life expectancy, meticulous surgical technique, and indications based on adequate bone quality. PMID:25802848

  14. Black Sprayable Molecular Adsorber Coating

    Data.gov (United States)

    National Aeronautics and Space Administration — The main objective of this technology project is to develop, optimize, and flight qualify a black version of the molecular adsorber coating and a conductive version...

  15. Self-stratifying antimicrobial coatings

    NARCIS (Netherlands)

    Yagci, M.B.

    2012-01-01

    Today, antimicrobial polymers/coatings are widely used in various areas, such as biomedical devices, pharmaceuticals, hospital buildings, textiles, food processing, and contact lenses, where sanitation is needed. Such wide application facilities have made antimicrobial materials very attractive for

  16. Smart Coatings for Corrosion Protection

    Science.gov (United States)

    Calle, Luz Marina; Li, Wendy; Buhrow, Jerry W.; Johnsey, Marissa N.

    2016-01-01

    Nearly all metals and their alloys are subject to corrosion that causes them to lose their structural integrity or other critical functionality. It is essential to detect corrosion when it occurs, and preferably at its early stage, so that action can be taken to avoid structural damage or loss of function. Protective coatings are the most commonly used method of corrosion control. However, progressively stricter environmental regulations have resulted in the ban of many commercially available corrosion protective coatings due to the harmful effects of their solvents or corrosion inhibitors. This work concerns the development of a multifunctional, smart coating for the autonomous control of corrosion. This coating is being developed to have the inherent ability to detect the chemical changes associated with the onset of corrosion and respond autonomously to indicate it and control it.

  17. Dielectric coatings on metal substrates

    International Nuclear Information System (INIS)

    Glaros, S.S.; Baker, P.; Milam, D.

    1976-01-01

    Large aperture, beryllium substrate-based mirrors have been used to focus high intensity pulsed laser beams. Finished surfaces have high reflectivity, low wavefront distortion, and high laser damage thresholds. This paper describes the development of a series of metallic coatings, surface finishing techniques, and dielectric overcoatings to meet specified performance requirements. Beryllium substrates were coated with copper, diamond-machined to within 5 micro-inches to final contour, nickel plated, and abrasively figured to final contour. Bond strengths for several bonding processes are presented. Dielectric overcoatings were deposited on finished multimetallic substrates to increase both reflectivity and the damage thresholds. Coatings were deposited using both high and low temperature processes which induce varying stresses in the finished coating substrate system. Data are presented to show the evolution of wavefront distortion, reflectivity, and damage thresholds throughout the many steps involved in fabrication

  18. Cementless Hydroxyapatite Coated Hip Prostheses

    Directory of Open Access Journals (Sweden)

    Antonio Herrera

    2015-01-01

    Full Text Available More than twenty years ago, hydroxyapatite (HA, calcium phosphate ceramics, was introduced as a coating for cementless hip prostheses. The choice of this ceramic is due to its composition being similar to organic apatite bone crystals. This ceramic is biocompatible, bioactive, and osteoconductive. These qualities facilitate the primary stability and osseointegration of implants. Our surgical experience includes the implantation of more than 4,000 cementless hydroxyapatite coated hip prostheses since 1990. The models implanted are coated with HA in the acetabulum and in the metaphyseal area of the stem. The results corresponding to survival and stability of implants were very satisfactory in the long-term. From our experience, HA-coated hip implants are a reliable alternative which can achieve long term survival, provided that certain requirements are met: good design selection, sound choice of bearing surfaces based on patient life expectancy, meticulous surgical technique, and indications based on adequate bone quality.

  19. Electrically conductive polymer concrete coatings

    Science.gov (United States)

    Fontana, Jack J.; Elling, David; Reams, Walter

    1990-01-01

    A sprayable electrically conductive polymer concrete coating for vertical d overhead applications is described. The coating is permeable yet has low electrical resistivity (<10 ohm-cm), good bond strength to concrete substrates, and good weatherability. A preferred formulation contains about 60 wt % calcined coke breeze, 40 wt % vinyl ester with 3.5 wt % modified bentonite clay. Such formulations apply evenly and provide enough rigidity for vertical or overhead structures so there is no drip or sag.

  20. Nanocrystalline diamond coatings for machining

    Energy Technology Data Exchange (ETDEWEB)

    Frank, M.; Breidt, D.; Cremer, R. [CemeCon AG, Wuerselen (Germany)

    2007-07-01

    This history of CVD diamond synthesis goes back to the fifties of the last century. However, the scientific and economical potential was only gradually recognized. In the eighties, intensive worldwide research on CVD diamond synthesis and applications was launched. Industrial products, especially diamond-coated cutting tools, were introduced to the market in the middle of the nineties. This article shows the latest developments in this area, which comprises nanocrystalline diamond coating structures. (orig.)

  1. Dry and coating of powders

    International Nuclear Information System (INIS)

    Alonso, M.; Alguacil, F. J.

    1999-01-01

    This paper presents a review on the mixing and coating of powders by dry processes. The reviews surveys fundamental works on mixture characterization (mixing index definitions and sampling techniques), mixing mechanisms and models, segregation with especial emphasis on free-surface segregation, mixing of cohesive powders and interparticle forces, ordered mixing (dry coating) including mechanism, model and applications and mixing equipment selection. (Author) 180 refs

  2. Silicone nanocomposite coatings for fabrics

    Science.gov (United States)

    Eberts, Kenneth (Inventor); Lee, Stein S. (Inventor); Singhal, Amit (Inventor); Ou, Runqing (Inventor)

    2011-01-01

    A silicone based coating for fabrics utilizing dual nanocomposite fillers providing enhanced mechanical and thermal properties to the silicone base. The first filler includes nanoclusters of polydimethylsiloxane (PDMS) and a metal oxide and a second filler of exfoliated clay nanoparticles. The coating is particularly suitable for inflatable fabrics used in several space, military, and consumer applications, including airbags, parachutes, rafts, boat sails, and inflatable shelters.

  3. Coating of silicon pore optics

    DEFF Research Database (Denmark)

    Cooper-Jensen, Carsten P.; Ackermann, M.; Christensen, Finn Erland

    2009-01-01

    For the International X-ray observatory (IXO), a mirror module with an effective area of 3 m2 at 1.25 keV and at least 0.65 m2 at 6 keV has to be realized. To achieve this goal, coated silicon pore optics has been developed over the last years. One of the challenges is to coat the Si plates...

  4. Damage-resistant brittle coatings

    Energy Technology Data Exchange (ETDEWEB)

    Lawn, B.R.; Lee, K.S. [National Inst. of Stand. and Technol., Gaithersburg, MD (United States). Mater. Sci. and Eng. Lab.; Chai, H. [Tel Aviv Univ. (Israel). Faculty of Engineering; Pajares, A. [Universidad de Extremadura, Badajoz (Spain). Dept. de Fisica; Kim, D.K. [Korea Advanced Inst. of Science and Technolgy, Taejon (Korea). Dept. of Materials Science and Engineering; Wuttiphan, S. [National Metal and Materials Technology Center, Bangkok (Thailand); Peterson, I.M. [Corning Inc., NY (United States); Hu Xiaozhi [Western Australia Univ., Nedlands, WA (Australia). Dept. of Mechanical and Materials Engineering

    2000-11-01

    Laminate structures consisting of hard, brittle coatings and soft, tough substrates are important in a wide variety of engineering applications, biological structures, and traditional pottery. In this study the authors introduce a new approach to the design of damage-resistant brittle coatings, based on a combination of new and existing relations for crack initiation in well-defined contact-induced stress fields. (orig.)

  5. Corrosion resistant neutron absorbing coatings

    Science.gov (United States)

    Choi, Jor-Shan [El Cerrito, CA; Farmer, Joseph C [Tracy, CA; Lee, Chuck K [Hayward, CA; Walker, Jeffrey [Gaithersburg, MD; Russell, Paige [Las Vegas, NV; Kirkwood, Jon [Saint Leonard, MD; Yang, Nancy [Lafayette, CA; Champagne, Victor [Oxford, PA

    2012-05-29

    A method of forming a corrosion resistant neutron absorbing coating comprising the steps of spray or deposition or sputtering or welding processing to form a composite material made of a spray or deposition or sputtering or welding material, and a neutron absorbing material. Also a corrosion resistant neutron absorbing coating comprising a composite material made of a spray or deposition or sputtering or welding material, and a neutron absorbing material.

  6. Sustained release vancomycin-coated titanium alloy using a novel electrostatic dry powder coating technique may be a potential strategy to reduce implant-related infection.

    Science.gov (United States)

    Han, Jing; Yang, Yi; Lu, Junren; Wang, Chenzhong; Xie, Youtao; Zheng, Xuebin; Yao, Zhenjun; Zhang, Chi

    2017-07-24

    In order to tackle the implant-related infection, a novel way was developed in this study to coat vancomycin particles mixed with controlled release coating materials onto the surface of titanium alloy by using an electrostatic dry powder coating technique. To characterize this sustained release antibacterial coating, surface morphology, in vitro and in vivo drug release were sequentially evaluated. In vitro cytotoxicity was tested by Cell Counting Kit-8 (CCK-8) assay and cytological changes were observed by inverted microscope. The antibacterial properties against MRSA, including a bacterial growth inhibition assay and a colony-counting test by spread plate method were performed. Results indicated that the vancomycin-coated sample was biocompatible for Human osteoblast cell line MG-63 and displayed effective antibacterial ability against MRSA. The coating film was revealed uniform by scanning electron microscopy. Both the in vitro and in vivo drug release kinetics showed an initially high release rate, followed by an extended period of sustained drug release over 7 days. These results suggest that with good biocompatibility and antibacterial ability, the sustained release antibacterial coating of titanium alloy using our novel electrostatic dry powder coating process may provide a promising candidate for the treatment of orthopedic implant-related infection.

  7. HVOF-Sprayed Nano TiO2-HA Coatings Exhibiting Enhanced Biocompatibility

    Science.gov (United States)

    Lima, R. S.; Dimitrievska, S.; Bureau, M. N.; Marple, B. R.; Petit, A.; Mwale, F.; Antoniou, J.

    2010-01-01

    Biomedical thermal spray coatings produced via high-velocity oxy-fuel (HVOF) from nanostructured titania (n-TiO2) and 10 wt.% hydroxyapatite (HA) (n-TiO2-10wt.%HA) powders have been engineered as possible future alternatives to HA coatings deposited via air plasma spray (APS). This approach was chosen due to (i) the stability of TiO2 in the human body (i.e., no dissolution) and (ii) bond strength values on Ti-6Al-4V substrates more than two times higher than those of APS HA coatings. To explore the bioperformance of these novel materials and coatings, human mesenchymal stem cells (hMSCs) were cultured from 1 to 21 days on the surface of HVOF-sprayed n-TiO2 and n-TiO2-10 wt.%HA coatings. APS HA coatings and uncoated Ti-6Al-4V substrates were employed as controls. The profiles of the hMSCs were evaluated for (i) cellular proliferation, (ii) biochemical analysis of alkaline phosphatase (ALP) activity, (iii) cytoskeleton organization (fluorescent/confocal microscopy), and (iv) cell/substrate interaction via scanning electron microscopy (SEM). The biochemical analysis indicated that the hMSCs cultured on n-TiO2-10 wt.%HA coatings exhibited superior levels of bioactivity than hMSCs cultured on APS HA and pure n-TiO2 coatings. The cytoskeleton organization demonstrated a higher degree of cellular proliferation on the HVOF-sprayed n-TiO2-10wt.%HA coatings when compared to the control coatings. These results are considered promising for engineering improved performance in the next generation of thermally sprayed biomedical coatings.

  8. Characterization of gas tunnel type plasma sprayed hydroxyapatite-nanostructure titania composite coatings

    Science.gov (United States)

    Yugeswaran, S.; Kobayashi, A.; Ucisik, A. Hikmet; Subramanian, B.

    2015-08-01

    Hydroxyapatite (HA) can be coated onto metal implants as a ceramic biocompatible coating to bridge the growth between implants and human tissue. Meanwhile many efforts have been made to improve the mechanical properties of the HA coatings without affecting its bioactivity. In the present study, nanostructure titania (TiO2) was mixed with HA powder and HA-nanostructure TiO2 composite coatings were produced by gas tunnel type plasma spraying torch under optimized spraying conditions. For this purpose, composition of 10 wt% TiO2 + 90 wt% HA, 20 wt% TiO2 + 80 wt% HA and 30 wt% TiO2 + 70 wt% HA were selected as the feedstock materials. The phase, microstructure and mechanical properties of the coatings were characterized. The obtained results validated that the increase in weight percentage of nanostructure TiO2 in HA coating significantly increased the microhardness, adhesive strength and wear resistance of the coatings. Analysis of the in vitro bioactivity and cytocompatibility of the coatings were done using conventional simulated body fluid (c-SBF) solution and cultured green fluorescent protein (GFP) labeled marrow stromal cells (MSCs) respectively. The bioactivity results revealed that the composite coating has bio-active surface with good cytocompatibility.

  9. Controllable mineral coatings on PCL scaffolds as carriers for growth factor release.

    Science.gov (United States)

    Suárez-González, Darilis; Barnhart, Kara; Migneco, Francesco; Flanagan, Colleen; Hollister, Scott J; Murphy, William L

    2012-01-01

    In this study, we have developed mineral coatings on polycaprolactone scaffolds to serve as templates for growth factor binding and release. Mineral coatings were formed using a biomimetic approach that consisted in the incubation of scaffolds in modified simulated body fluids (mSBF). To modulate the properties of the mineral coating, which we hypothesized would dictate growth factor release, we used carbonate (HCO(3)) concentration in mSBF of 4.2 mm, 25 mm, and 100 mm. Analysis of the mineral coatings formed using scanning electron microscopy indicated growth of a continuous layer of mineral with different morphologies. X-ray diffraction analysis showed peaks associated with hydroxyapatite, the major inorganic constituent of human bone tissue in coatings formed in all HCO(3) concentrations. Mineral coatings with increased HCO(3) substitution showed more rapid dissolution kinetics in an environment deficient in calcium and phosphate but showed re-precipitation in an environment with the aforementioned ions. The mineral coating provided an effective mechanism for growth factor binding and release. Peptide versions of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP2) were bound with efficiencies up to 90% to mineral mineral-coated PCL scaffolds. We also demonstrated sustained release of all growth factors with release kinetics that were strongly dependent in the solubility of the mineral coating. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Cytocompatibility and antibacterial properties of zirconia coatings with different silver contents on titanium

    International Nuclear Information System (INIS)

    Huang, Heng-Li; Chang, Yin-Yu; Chen, Ya-Chi; Lai, Chih-Ho; Chen, Michael Y.C.

    2013-01-01

    This study used a twin-gun magnetron sputtering system to deposit ZrO 2 -silver (Ag) coatings on biograde pure-titanium implant materials, and the Ag content in the deposited coatings was controlled by the magnetron power. The films were then annealed using rapid thermal annealing at 350 °C for 2 min to induce the nucleation and growth of nanoparticles on the film surface. Staphylococcus aureus (S. aureus) and Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans) were used for in vitro antibacterial analyses. The cytocompatibility, mRNA expression, and adhesive morphology of human gingival fibroblast (HGF) cells on the coatings were also determined. The obtained results suggest that ZrO 2 -Ag composite coatings containing less than 10.6 at.% Ag show hydrophobicity, good viability and proliferation of HGF cells, and antibacterial effects on S. aureus and A. actinomycetemcomitans. Moreover, the antibacterial performance of ZrO 2 -Ag coatings is superior to that pure-titanium whilst maintaining biological compatibility. - Highlights: • The annealed ZrO 2 -Ag coatings showed a tetragonal-and-monoclinic structure. • Nanoparticles were well distributed in the annealed ZrO 2 -Ag composite coatings. • The ZrO 2 -Ag coated Ti showed hydrophobic feature. • The ZrO 2 -Ag showed good antibacterial performance. • The ZrO 2 -Ag showed good human gingival fibroblast cell viability

  11. Material Science Smart Coatings

    Energy Technology Data Exchange (ETDEWEB)

    Rubinstein, A. I. [Univ. of Nebraska Medical Center, Omaha, NE (United States); Sabirianov, R. F. [Univ. of Nebraska Medical Center, Omaha, NE (United States); Namavar, Fereydoon [Univ. of Nebraska Medical Center, Omaha, NE (United States)

    2014-07-01

    The contribution of electrostatic interactions to the free energy of binding between model protein and a ceramic implant surface in the aqueous solvent, considered in the framework of the nonlocal electrostatic model, is calculated as a function of the implant low-frequency dielectric constant. We show that the existence of a dynamically ordered (low-dielectric) interfacial solvent layer at the protein-solvent and ceramic-solvent interface markedly increases charging energy of the protein and ceramic implant, and consequently makes the electrostatic contribution to the protein-ceramic binding energy more favorable (attractive). Our analysis shows that the corresponding electrostatic energy between protein and oxide ceramics depends nonmonotonically on the dielectric constant of ceramic, εC. Obtained results indicate that protein can attract electrostatically to the surface if ceramic material has a moderate εC below or about 35 (in particularly ZrO2 or Ta2O5). This is in contrast to classical (local) consideration of the solvent, which demonstrates an unfavorable electrostatic interaction of protein with typical metal oxide ceramic materials (εC>10). Thus, a solid implant coated by combining oxide ceramic with a reduced dielectric constant can be beneficial to strengthen the electrostatic binding of the protein-implant complex.

  12. Silane based coating of aluminium mold

    DEFF Research Database (Denmark)

    2013-01-01

    having at least one closed cavity is provided, at least one surface of the at least one cavity being an aluminium surface coated with a silane based coating layer. The silane based anti-stiction coating improves the anti-stiction properties of the mold which may allow for molding and demolding...... of structures which would otherwise be difficult to mold. The resistance of the coated aluminium mold is significantly improved by applying a silane-based coating layer....

  13. Switchable antifouling coatings and uses thereof

    Science.gov (United States)

    Denton, Michele L. Baca; Dirk, Shawn M.; Johnson, Ross Stefan

    2017-02-28

    The present invention relates to antifouling coatings capable of being switched by using heat or ultraviolet light. Prior to switching, the coating includes an onium cation component having antimicrobial and antibacterial properties. Upon switching, the coating is converted to a conjugated polymer state, and the cationic component is released with any adsorbed biofilm layer. Thus, the coatings herein have switchable and releasable properties. Methods of making and using such coatings are also described.

  14. Radiation shielding properties of barite coated fabric by computer programme

    Energy Technology Data Exchange (ETDEWEB)

    Akarslan, F.; Molla, T. [Suleyman Demirel University, Engineering Fac. Textile Dep., Isparta (Turkey); Üncü, I. S. [Suleyman Demirel University, Technological Fac. Electrical-Electronic Eng. Dep., Isparta (Turkey); Kılıncarslan, S., E-mail: seref@tef.sdu.edu.tr [Suleyman Demirel University, Engineering Fac. Civil Eng. Dep., Isparta (Turkey); Akkurt, I. [Suleyman Demirel University, Art and Science Fac., Physics Dep., Isparta (Turkey)

    2015-03-30

    With the development of technology radiation started to be used in variety of different fields. As the radiation is hazardous for human health, it is important to keep radiation dose as low as possible. This is done mainly using shielding materials. Barite is one of the important materials in this purpose. As the barite is not used directly it can be used in some other materials such as fabric. For this purposes barite has been coated on fabric in order to improve radiation shielding properties of fabric. Determination of radiation shielding properties of coated fabric has been done by using computer program written C# language. With this program the images obtained from digital Rontgen films is used to determine radiation shielding properties in terms of image processing numerical values. Those values define radiation shielding and in this way the coated barite effect on radiation shielding properties of fabric has been obtained.

  15. Graphene: corrosion-inhibiting coating.

    Science.gov (United States)

    Prasai, Dhiraj; Tuberquia, Juan Carlos; Harl, Robert R; Jennings, G Kane; Rogers, Bridget R; Bolotin, Kirill I

    2012-02-28

    We report the use of atomically thin layers of graphene as a protective coating that inhibits corrosion of underlying metals. Here, we employ electrochemical methods to study the corrosion inhibition of copper and nickel by either growing graphene on these metals, or by mechanically transferring multilayer graphene onto them. Cyclic voltammetry measurements reveal that the graphene coating effectively suppresses metal oxidation and oxygen reduction. Electrochemical impedance spectroscopy measurements suggest that while graphene itself is not damaged, the metal under it is corroded at cracks in the graphene film. Finally, we use Tafel analysis to quantify the corrosion rates of samples with and without graphene coatings. These results indicate that copper films coated with graphene grown via chemical vapor deposition are corroded 7 times slower in an aerated Na(2)SO(4) solution as compared to the corrosion rate of bare copper. Tafel analysis reveals that nickel with a multilayer graphene film grown on it corrodes 20 times slower while nickel surfaces coated with four layers of mechanically transferred graphene corrode 4 times slower than bare nickel. These findings establish graphene as the thinnest known corrosion-protecting coating.

  16. Polymeric Coatings for Combating Biocorrosion

    Science.gov (United States)

    Guo, Jing; Yuan, Shaojun; Jiang, Wei; Lv, Li; Liang, Bin; Pehkonen, Simo O.

    2018-03-01

    Biocorrosion has been considered as big trouble in many industries and marine environments due to causing great economic loss. The main disadvantages of present approaches to prevent corrosion include being limited by environmental factors, being expensive, inapplicable to field, and sometimes inefficient. Studies show that polymer coatings with anti-corrosion and anti-microbial properties have been widely accepted as a novel and effective approach to preventbiocorrosion. The main purpose of this review is to summarize up the progressive status of polymer coatings used for combating microbially-induced corrosion. Polymers used to synthesize protective coatings are generally divided into three categories: i) traditional polymers incorporated with biocides, ii) antibacterial polymers containing quaternary ammonium compounds, and iii) conductive polymers. The strategies to synthesize polymer coatings resort mainly to grafting anti-bacterial polymers from the metal substrate surface using novel surface-functionalization approaches, such as free radical polymerization, chemically oxidative polymerization and surface-initiated atom transfer radical polymerization, as opposed to the traditional approaches of dip coating or spin coating.

  17. Electron beam-cured coating

    International Nuclear Information System (INIS)

    Kishi, Naoyuki

    1976-01-01

    The method for hardening coatings by the irradiation with electron beams is reviewed. The report is divided into seven parts, namely 1) general description and characteristics of electron beam-cured coating, 2) radiation sources of curing, 3) hardening conditions and reaction behaviour, 4) uses and advantages, 5) latest trends of the industry, 6) practice in the field of construction materials, and 7) economy. The primary characteristics of the electron beam hardening is that graft reaction takes place between base resin and coating to produce strong adhesive coating without any pretreatment. A variety of base resins are developed. High class esters of acrylic acid monomers and methacrylic acid monomers are mainly used as dilutants recently. At present, scanning type accelerators are used, but the practical application of the system producing electron beam of curtain type is expected. The dose rate dependence, the repetitive irradiation and the irradiation atmosphere are briefly described. The filed patent applications on the electron beam hardening were analyzed by the officer of Japan Patent Agency. The production lines for coatings by the electron beam hardening in the world are listed. In the electron beam-cured coating, fifty percent of given energy is consumed effectively for the electron beam hardening, and the solvents discharged from ovens and polluting atmosphere are not used, because the paints of high solid type is used. The running costs of the electron beam process are one sixth of the thermal oven process. (Iwakiri, K.)

  18. The Relationship Between Coat Color and Aggressive Behaviors in the Domestic Cat.

    Science.gov (United States)

    Stelow, Elizabeth A; Bain, Melissa J; Kass, Philip H

    2016-01-01

    The authors explored a possible relationship between coat color and aggressive behaviors in the domestic cat. This study used an Internet-based survey to collect information on coat color, affiliative behaviors toward cats/humans, agonistic behaviors toward cats/humans, other "problem" behaviors, and cat and guardian demographic data. A total of 1,432 cat guardians completed the online survey; after exclusions based on study protocol, data analysis included 1,274 completed surveys. Guardians reported sex-linked orange female (tortoiseshells, calicos, and "torbies"), black-and-white, and gray-and-white cats to be more frequently aggressive toward humans in 3 settings: during everyday interactions, during handling, and during veterinary visits. Kruskal-Wallis 1-way analysis of variance was used to compare possible differences between the 2 sexes and among different coat colors. Analyses of aggression due to handling, as well as aggression displayed during veterinarian visits, showed little difference among coat colors in these settings.

  19. Sol-gel derived bioactive coating on zirconia: Effect on flexural strength and cell proliferation.

    Science.gov (United States)

    Shahramian, Khalil; Leminen, Heidi; Meretoja, Ville; Linderbäck, Paula; Kangasniemi, Ilkka; Lassila, Lippo; Abdulmajeed, Aous; Närhi, Timo

    2017-11-01

    The purpose of this study was to evaluate the effect of sol-gel derived bioactive coatings on the biaxial flexural strength and fibroblast proliferation of zirconia, aimed to be used as an implant abutment material. Yttrium stabilized zirconia disc-shaped specimens were cut, ground, sintered, and finally cleansed ultrasonically in each of acetone and ethanol for 5 minutes. Three experimental groups (n = 15) were fabricated, zirconia with sol-gel derived titania (TiO 2 ) coating, zirconia with sol-gel derived zirconia (ZrO 2 ) coating, and non-coated zirconia as a control. The surfaces of the specimens were analyzed through images taken using a scanning electron microscope (SEM), and a non-contact tapping mode atomic force microscope (AFM) was used to record the surface topography and roughness of the coated specimens. Biaxial flexural strength values were determined using the piston-on-three ball technique. Human gingival fibroblast proliferation on the surface of the specimens was evaluated using AlamarBlue assay™. Data were analyzed using a one-way analysis of variance (ANOVA) followed by Tukey's post-hoc test. Additionally, the biaxial flexural strength data was also statistically analyzed with the Weibull distribution. The biaxial flexural strength of zirconia specimens was unaffected (p > 0.05). Weibull modulus of TiO 2 coated and ZrO 2 coated groups (5.7 and 5.4, respectively) were lower than the control (8.0). Specimens coated with ZrO 2 showed significantly lower fibroblast proliferation compared to other groups (p sol-gel derived coatings have no influence on the flexural strength of zirconia. ZrO 2 coated specimens showed significantly lower cell proliferation after 12 days than TiO 2 coated or non-coated control. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2401-2407, 2017. © 2016 Wiley Periodicals, Inc.

  20. Coatings and Tints of Spectacle Lenses

    Directory of Open Access Journals (Sweden)

    H. Zeki Büyükyıldız

    2012-10-01

    Full Text Available Spectacle lenses are made of mineral or organic (plastic materials. Various coatings and tints are applied to the spectacle lenses according to the characteristic of the lens material, and for the personal needs and cosmetic purpose. The coatings may be classified in seven groups: 1 Anti-reflection coatings, 2 Hard coatings, 3 Clean coat, 4 Mirror coatings, 5 Color tint coating (one of coloring processes, 6 Photochromic coating (one of photochromic processes, and 7 Anti-fog coatings. Anti-reflection coatings reduce unwanted reflections from the lens surfaces and increase light transmission. Hard coatings are applied for preventing the plastic lens surface from scratches and abrasion. Hard coatings are not required for the mineral lenses due to their hardness. Clean coat makes the lens surface smooth and hydrophobic. Thus, it prevents the adherence of dust, tarnish, and dirt particles on the lens surface. Mirror coatings are applied onto the sunglasses for cosmetic purpose. Color tinted and photochromic lenses are used for sun protection and absorption of the harmful UV radiations. Anti-fog coatings make the lens surface hydrophilic and prevent the coalescence of tiny water droplets on the lens surface that reduces light transmission. (Turk J Ophthalmol 2012; 42: 359-69

  1. Antibacterial property of fabrics coated by magnesium-based brucites

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ying; Sha, Lin; Zhao, Jiao; Li, Qian; Zhu, Yimin, E-mail: ntp@dlmu.edu.cn; Wang, Ninghui

    2017-04-01

    Highlights: • Magnesium-based antibacterial agents composited by brucites with different particle sizes were proposed for the first time. • The coating process for making antibacterial fabrics was easy to operate and apply in industrial application. • The materials used in the antibacterial fabrics were environmental-friendly and cost-effective. • Reduction percentage of as-prepared antibacterial fabrics against E. coli and S. aureus reached to 96.6%, 100% respectively. • The antibacterial fabrics attained excellent washing durability. - Abstract: A kind of environmental-friendly magnesium-based antibacterial agent was reported for the first time, which was composited by brucites with different particle sizes. The antibacterial fabrics were produced by coating the magnesium-based antibacterial agents on the 260T polyester pongee fabrics with waterborne polyurethane. The coating process was simple, low-cost, and harmless to human health and environment. Characteristics of the antibacterial agents and fabrics were studied by particulate size distribution analyzer (PSDA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The results demonstrated that the coating layer was covered tightly on the fabrics and compositing of different particles by a certain proportion made full filling of the coating layer. Meanwhile, compositing did not change the structure of brucites. The antibacterial fabrics presented strong antibacterial properties against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), with the reduction percentage of 96.6% and 100%, respectively, and the antibacterial fabrics attained excellent washing durability.

  2. Analysis of Capillary Coating Die Flow in an Optical Fiber Coating Applicator

    OpenAIRE

    Kyoungjin Kim

    2011-01-01

    Viscous heating becomes significant in the high speed resin coating process of glass fibers for optical fiber manufacturing. This study focuses on the coating resin flows inside the capillary coating die of optical fiber coating applicator and they are numerically simulated to examine the effects of viscous heating and subsequent temperature increase in coating resin. Resin flows are driven by fast moving glass fiber and the pressurization at the coating die inlet, while ...

  3. Pin Wire Coating Trip Report

    International Nuclear Information System (INIS)

    Spellman, G P

    2004-01-01

    A meeting to discuss the current pin wire coating problems was held at the Reynolds plant in Los Angeles on 2MAR04. The attendance list for Reynolds personnel is attached. there was an initial presentation which gave a brief history and the current status of pin wire coating at Reynolds. There was a presentation by Lori Primus on the requirements and issues for the coating. There was a presentation by Jim Smith of LANL on the chemistry and to some extent process development done to date. There was a long session covering what steps should be taken in the short term and, to a lesser extent, the long term. The coating currently being used is a blend of two polymers, polyethersulfone and polyparabanic acid (PPA) and some TiO2 filler. This system was accepted and put into production when the pin wire coating was outsourced to another company in 1974. When that company no longer was interested, the wire coating was brought in-house to Reynolds. At that time polyparabanic acid was actually a commercial product available from Exxon under the trade name Tradlon. However, it appears that the material used at Reynolds was synthesized locally. Also, it appears that a single large batch was synthesized in that time period and used up to 1997 when the supply ran out. The reason for the inclusion of TiO2 is not known although it does act as a rheological thickener. However, a more controlled thickening can be obtained with materials such as fumed silica. This material would have less likelihood of causing point imperfections in the coatings. Also, the mixing technique being used for all stages of the process is a relatively low shear ball mill process and the author recommends a high shear process such as a three roll paint mill, at least for the final mixing. Since solvent is added to the powder at Reynolds, it may be that they need to have the paint mill there

  4. Advanced Marine Coatings for Naval Vessels - Phase 1. Antifouling and Fouling Release Coatings

    National Research Council Canada - National Science Library

    McCarthy, Gregory

    2003-01-01

    ... in combinatorial materials chemistry high-throughput discovery and evaluation methodology. The protective coatings application being addressed is environmentally compliant antifouling and fouling release coating for Navy ships...

  5. carbon coated copper grids

    African Journals Online (AJOL)

    PRECIOUS

    2009-11-02

    Nov 2, 2009 ... Structure, Academic Press Inc (London) Ltd., London. Hemmes JH, Winkler KC, Kool SM (1960). Virus survival as a seasonal factor in influenza and poliomyelitis. Nature, 188: 430-431. Ijaz MK (1985). Studies on the airborne survival of rotaviruses and a human coronavirus. Ph.D. thesis, Univ. of Ottawa, ...

  6. Corrosion behavior of biodegradable material AZ31 coated with beeswax-colophony resin

    Science.gov (United States)

    Gumelar, Muhammad Dikdik; Putri, Nur Ajrina; Anggaravidya, Mahendra; Anawati, Anawati

    2018-05-01

    Magnesium (Mg) and its alloys are potential candidates for biodegradable implant materials owing to their ability to degrade spontaneously in a physiological environment. However, the degradation rate is still considered too fast in human body solution. A coating is typically applied to slowdown corrosion rate of Mg alloys. In this work, an organic coating of mixture beeswax-colophony with ratios of 40-60, 50-50, and 60-40 in wt% was synthesized and applied on commercial magnesium alloyAZ31. The coated specimens were then characterized with SEM and XRF. The corrosion behavior of the coated specimens was evaluated by immersion test in 0.9 wt% NaCl solution at 37°C for 14 days. The results indicated that the coating material improved the corrosion resistance of the AZ31 alloy.

  7. Comparison of cell uptake, biodistribution and tumor retention of folate-coated and PEG-coated gadolinium nanoparticles in tumor-bearing mice.

    Science.gov (United States)

    Oyewumi, Moses O; Yokel, Robert A; Jay, Michael; Coakley, Tricia; Mumper, Russell J

    2004-03-24

    The purpose of these studies was to compare the cell uptake, biodistribution and tumor retention of folate-coated and PEG-coated gadolinium (Gd) nanoparticles. Gd is a potential agent for neutron capture therapy (NCT) of tumors. Gd nanoparticles were engineered from oil-in-water microemulsion templates. To obtain folate-coated nanoparticles, a folate ligand [folic acid chemically linked to distearoylphosphatidylethanolamine (DSPE) via a PEG spacer MW 3350] was included in nanoparticle preparations. Similarly, control nanoparticles were coated with DSPE-PEG-MW 3350 (PEG-coated). Nanoparticles were characterized based on size, size distribution, morphology, biocompatibility and tumor cell uptake. In vivo studies were carried out in KB (human nasopharyngeal carcinoma) tumor-bearing athymic mice. Biodistribution and tumor retention studies were carried out at pre-determined time intervals after injection of nanoparticles (10 mg/kg). Gd nanoparticles did not aggregate platelets or activate neutrophils. The retention of nanoparticles in the blood 8, 16 and 24 h post-injection was 60%, 13% and 11% of the injected dose (ID), respectively. A maximum Gd tumor localization of 33+/-7 microg Gd/g was achieved. Both folate-coated and PEG-coated nanoparticles had comparable tumor accumulation. However, the cell uptake and tumor retention of folate-coated nanoparticles was significantly enhanced over PEG-coated nanoparticles. Thus, the benefits of folate ligand coating were to facilitate tumor cell internalization and retention of Gd-nanoparticles in the tumor tissue. The engineered nanoparticles may have potential in tumor-targeted delivery of Gd thereby enhancing the therapeutic success of NCT.

  8. Process for preparing coating materials

    International Nuclear Information System (INIS)

    Ryoke, Hideyasu; Kobayashi, Juichi; Kobayashi, Kei.

    1972-01-01

    A coating material curable with ionizing radiations or ultraviolet radiation can be prepared by reacting a compound (A) having one OH group and at least one α,β-ethylenic or allyl group with a polyisocyanate. (A) is a diester of a dicarboxylic acid. One of the ester groups may have a terminal α,β-ethylenic or allyl group and the other contains one OH and one α,β-ethylenic or allyl group. (A) is reacted with a polyisocyanate to yield an urethane. The latter may be diluted with a vinyl monomer. When exposed to a radiation, the coating material cures to give a film excellent in adhesion, impact strength and resistances to pollution, water and solvents. Dose of the ionizing radiation (α-, β-, γ-rays, electron beams) is 0.2-20 Mrad. In one example, 116 parts of 2-hydroxyethyl acrylate was reacted with 148 parts of phthalic anhydride and 142 parts of glycidyl methacrylate to give (A). (A) was reacted with 87 parts of tolylenediisocyanate. A metallic panel was coated with the coating material and cured with electron beams (5 Mrad). Pencil hardness was H, and gel fraction measured in acetone was above 97%. The coating was excellent in resistances to solvent and chemicals, impact strength and adhesion. (Kaichi, S.)

  9. Chromate conversion coatings and their current application

    Directory of Open Access Journals (Sweden)

    P. Pokorny

    2016-04-01

    Full Text Available This paper describes formation, composition and possible production technologies of application chromate coatings. Summation of common examples of applications of these coatings in corrosion protection of metals and alloys is provided. Individual chromate coatings are divided by their dominant anions either with CrVI or CrIII. Restrictions of chromate coatings with dominantly CrVI and related toxicity of hexavalent chromium is discussed in detail. In conclusion, examples of both chromium and other, alternative coatings are summed up. Application of these coatings as a protection for concrete hot-dip galvanized reinforcement is also reviewed.

  10. Radiation curable compositions useful as transfer coatings

    International Nuclear Information System (INIS)

    McCarty, W.H.; Nagy, F.A.; Guarino, J.P.

    1983-01-01

    The invention is on a method for applying a coating to a thin porous substrate and reducing absorption of the coating into the substrate by applying a radiation-curable composition to a carrying web; the radiation-curable coating composition having a crosslink density of 0.02 to about 1.0 determined by calculation of the gram moles of branch points per 100 grams of uncured coating, and a glass transition temperature of the radiation cured coating within the approximate range of -80 degrees to +100 degrees C. The carrying web being of a nature such that the coating composition, when cured, will not adhere to its surface

  11. Frictionless contact of two parallel congruent rigid cylindrical surfaces coated with thin elastic transversely isotropic incompressible layers: an analytic solution

    Czech Academy of Sciences Publication Activity Database

    Hlaváček, Miroslav

    2006-01-01

    Roč. 25, č. 3 (2006), s. 497-508 ISSN 0997-7538 R&D Projects: GA ČR(CZ) GA103/04/0150 Institutional research plan: CEZ:AV0Z20710524 Keywords : contact of coated cylinders * elastic transversely isotropic incompressible coating * human ankle joint Subject RIV: JJ - Other Materials Impact factor: 0.897, year: 2006

  12. Immobilisation of hydroxyapatite-collagen on polydopamine grafted stainless steel 316L: Coating adhesion and in vitro cells evaluation.

    Science.gov (United States)

    Tapsir, Zafirah; Jamaludin, Farah H; Pingguan-Murphy, Belinda; Saidin, Syafiqah

    2018-02-01

    The utilisation of hydroxyapatite and collagen as bioactive coating materials could enhance cells attachment, proliferation and osseointegration. However, most methods to form crystal hydroxyapatite coating do not allow the incorporation of polymer/organic compound due to production phase of high sintering temperature. In this study, a polydopamine film was used as an intermediate layer to immobilise hydroxyapatite-collagen without the introduction of high sintering temperature. The surface roughness, coating adhesion, bioactivity and osteoblast attachment on the hydroxyapatite-collagen coating were assessed as these properties remains unknown on the polydopamine grafted film. The coating was developed by grafting stainless steel 316L disks with a polydopamine film. Collagen type I fibres were then immobilised on the grafted film, followed by the biomineralisation of hydroxyapatite. The surface roughness and coating adhesion analyses were later performed by using AFM instrument. An Alamar Blue assay was used to determine the cytotoxicity of the coating, while an alkaline phosphatase activity test was conducted to evaluate the osteogenic differentiation of human fetal osteoblasts on the coating. Finally, the morphology of cells attachment on the coating was visualised under FESEM. The highest RMS roughness and coating adhesion were observed on the hydroxyapatite-collagen coating (hydroxyapatite-coll-dopa). The hydroxyapatite-coll-dopa coating was non-toxic to the osteoblast cells with greater cells proliferation, greater level of alkaline phosphate production and more cells attachment. These results indicate that the immobilisation of hydroxyapatite and collagen using an intermediate polydopamine is identical to enhance coating adhesion, osteoblast cells attachment, proliferation and differentiation, and thus could be implemented as a coating material on orthopaedic and dental implants.

  13. Optical characterization of antirelaxation coatings

    Science.gov (United States)

    Tsvetkov, S.; Gateva, S.; Cartaleva, S.; Mariotti, E.; Nasyrov, K.

    2018-03-01

    Antirelaxation coatings (ARC) are used in optical cells containing alkali metal vapor to reduce the depolarization of alkali atoms after collisions with the cell walls. The long-lived ground state polarization is a basis for development of atomic clocks, magnetometers, quantum memory, slow light experiments, precision measurements of fundamental symmetries etc. In this work, a simple method for measuring the number of collisions of the alkali atoms with the cell walls without atomic spin randomization (Nasyrov et al., Proc. SPIE (2015)) was applied to characterize the AR properties of two PDMS coatings prepared from different solutions in ether (PDMS 2% and PDMS 5%). We observed influence of the light-induced atomic desorption (LIAD) on the AR properties of coatings.

  14. Radiation-curable coating composition

    International Nuclear Information System (INIS)

    Mibae, Jiro; Kawamura, Hiroshi; Takahashi, Masao.

    1970-01-01

    A radiation-curable coating composition, suitable for metal precoating, is provided. The composition is prepared by mixing 50 to 90 parts of a long chain fatty acid ester (A) with 10 to 50 parts of monomer (B) which is copolymerizable with (A). (A) is prepared by reacting a dimer acid (particularly the dimer of linolenic acid) with hydroxyalkyl methacrylate or glycidyl methacrylate. Upon irradiation with electron beams (0.1 to 3 MeV) the composition cures to yield a coating of high adhesion, impact resistance and bending resistance. In one example, 100 g of dimer acid (Versadime 216, manufactured by General Mills) was esterified with 50 g of 2-hydroxyethyl methacrylate. A zinc plated iron plate was coated with the product and irradiated with electron beams (2 Mrad). Pencil hardness was F; adhesion 0: impact resistance (Du Pont) 1 kg x 30 cm; bending resistance 2T. (Kaichi, S.)

  15. Evaluation of End Mill Coatings

    Energy Technology Data Exchange (ETDEWEB)

    L. J. Lazarus; R. L. Hester,

    2005-08-01

    Milling tests were run on families of High Speed Steel (HSS) end mills to determine their lives while machining 304 Stainless Steel. The end mills tested were made from M7, M42 and T15-CPM High Speed Steels. The end mills were also evaluated with no coatings as well as with Titanium Nitride (TiN) and Titanium Carbo-Nitride (TiCN) coatings to determine which combination of HSS and coating provided the highest increase in end mill life while increasing the cost of the tool the least. We found end mill made from M42 gave us the largest increase in tool life with the least increase in cost. The results of this study will be used by Cutting Tool Engineering in determining which end mill descriptions will be dropped from our tool catalog.

  16. Studies on soft centered coated snacks.

    Science.gov (United States)

    Pavithra, A S; Chetana, Ramakrishna; Babylatha, R; Archana, S N; Bhat, K K

    2013-04-01

    Roasted groundnut seeds, amaranth and dates pulp formed the center filling which was coated with sugar, breadings, desiccated coconut and roasted Bengalgram flour (BGF) to get 4 coated snacks. Physicochemical characteristics, microbiological profile, sorption behaviour and sensory quality of 4 coated snacks were determined. Centre filling to coating ratio of the products were in the range of 3:2-7:1, the product having BGF coating had the thinnest coating. Center filling had soft texture and the moisture content was 10.2-16.2% coating had lower moisture content (4.4-8.6%) except for Bengal gram coating, which had 11.1% moisture. Sugar coated snack has lowest fat (11.6%) and protein (7.2%) contents. Desiccated coconut coated snack has highest fat (25.4%) and Bengal gram flour coated snack had highest protein content (15.4%). Sorption studies showed that the coated snack had critical moisture content of 11.2-13.5%. The products were moisture sensitive and hence require packaging in films having higher moisture barrier property. In freshly prepared snacks coliforms, yeast and mold were absent. Mesophillic aerobes count did not show significant change during 90 days of storage at 27 °C and 37 °C. Sensory analysis showed that products had a unique texture due to combined effect of fairly hard coating and soft center. Flavour and overall quality of all the products were rated as very good.

  17. Nano-Ceramic Coated Plastics

    Science.gov (United States)

    Cho, Junghyun

    2013-01-01

    Plastic products, due to their durability, safety, and low manufacturing cost, are now rapidly replacing cookware items traditionally made of glass and ceramics. Despite this trend, some still prefer relatively expensive and more fragile ceramic/glassware because plastics can deteriorate over time after exposure to foods, which can generate odors, bad appearance, and/or color change. Nano-ceramic coatings can eliminate these drawbacks while still retaining the advantages of the plastic, since the coating only alters the surface of the plastic. The surface coating adds functionality to the plastics such as self-cleaning and disinfectant capabilities that result from a photocatalytic effect of certain ceramic systems. These ceramic coatings can also provide non-stick surfaces and higher temperature capabilities for the base plastics without resorting to ceramic or glass materials. Titanium dioxide (TiO2) and zinc oxide (ZnO) are the candidates for a nano-ceramic coating to deposit on the plastics or plastic films used in cookware and kitchenware. Both are wide-bandgap semiconductors (3.0 to 3.2 eV for TiO2 and 3.2 to 3.3 eV for ZnO), so they exhibit a photocatalytic property under ultraviolet (UV) light. This will lead to decomposition of organic compounds. Decomposed products can be easily washed off by water, so the use of detergents will be minimal. High-crystalline film with large surface area for the reaction is essential to guarantee good photocatalytic performance of these oxides. Low-temperature processing (nano-ceramic coatings (TiO2, ZnO) on plastic materials (silicone, Teflon, PET, etc.) that can possess both photocatalytic oxide properties and flexible plastic properties. Processing cost is low and it does not require any expensive equipment investment. Processing can be scalable to current manufacturing infrastructure.

  18. A Novel Human T-lymphotropic Virus Type 1c Molecular Variant in an Indigenous Individual from New Caledonia, Melanesia.

    Directory of Open Access Journals (Sweden)

    Olivier Cassar

    2017-01-01

    Full Text Available Human T-Lymphotropic Virus type 1 (HTLV-1 is endemic among people of Melanesian descent in Papua New Guinea, Solomon Islands and Vanuatu, and in Indigenous populations from Central Australia. Molecular studies revealed that these Australo-Melanesian strains constitute the highly divergent HTLV-1c subtype. New Caledonia is a French overseas territory located in the Southwest Pacific Ocean. HTLV-1 situation is poorly documented in New Caledonia and the molecular epidemiology of HTLV-1 infection remains unknown.Studying 500 older adults Melanesian natives from New Caledonia, we aim to evaluate the HTLV-1 seroprevalence and to molecularly characterize HTLV-1 proviral strains.Plasma from 262 men and 238 females (age range: 60-96 years old, mean age: 70.5 were screened for anti-HTLV-1 antibodies by particle agglutination (PA and indirect immunofluorescence assay (IFA. Serological confirmation was obtained using Western blot assay. DNAs were extracted from peripheral blood buffy coat of HTLV-1 seropositive individuals, and subjected to four series of PCR (LTR-gag; pro-pol; pol-env and tax-LTR. Primers were designed from highly common conserved regions of the major HTLV-1 subtypes to characterize the entire HTLV-1 proviral genome.Among 500 samples, 3 were PA and IFA positive. The overall seroprevalence was 0.6%. The DNA sample from 1 New Caledonian woman (NCP201 was found positive by PCR and the complete HTLV-1 proviral genome (9,033-bp was obtained. The full-length HTLV-1 genomic sequence from a native woman from Vanuatu (EM5, obtained in the frame of our previous studies, was also characterized. Both sequences belonged to the HTLV-1c Australo-Melanesian subtype. The NCP201 strain exhibited 0.3% nucleotide divergence with the EM5 strain from Vanuatu. Furthermore, divergence reached 1.1% to 2.9% with the Solomon and Australian sequences respectively. Phylogenetic analyses on a 522-bp-long fragment of the gp21-env gene showed the existence of two major

  19. On niobium sputter coated cavities

    International Nuclear Information System (INIS)

    Arnolds-Mayer, G.; Kaufmann, U.; Downar, H.

    1988-01-01

    To coat copper cavities with a thin film of niobium, facilities for electropolishing and sputter deposition have been installed at Dornier. Experiments have been performed on samples to optimize electropolishing and deposition parameters. In this paper, characteristics concerning surface properties, adhesion of the niobium film to the copper substrate, and film properties were studied on planar samples. A 1.5 GHz single cell cavity made from oxygen free high conductivity (OFHC) copper was sputter coated twice. First rf measurements were performed in the temperature range from 300 K to 2 K

  20. Corrosion-resistant coating development

    Energy Technology Data Exchange (ETDEWEB)

    Stinton, D.P.; Kupp, D.M.; Martin, R.L. [Oak Ridge National Lab., TN (United States)

    1997-12-01

    SiC-based heat exchangers have been identified as the prime candidate material for use as heat exchangers in advanced combined cycle power plants. Unfortunately, hot corrosion of the SiC-based materials created by alkali metal salts present in the combustion gases dictates the need for corrosion-resistant coatings. The well-documented corrosion resistance of CS-50 combined with its low (and tailorable) coefficient of thermal expansion and low modulus makes CS-50 an ideal candidate for this application. Coatings produced by gelcasting and traditional particulate processing have been evaluated.

  1. Coated carbon nanotube array electrodes

    Science.gov (United States)

    Ren, Zhifeng [Newton, MA; Wen, Jian [Newton, MA; Chen, Jinghua [Chestnut Hill, MA; Huang, Zhongping [Belmont, MA; Wang, Dezhi [Wellesley, MA

    2008-10-28

    The present invention provides conductive carbon nanotube (CNT) electrode materials comprising aligned CNT substrates coated with an electrically conducting polymer, and the fabrication of electrodes for use in high performance electrical energy storage devices. In particular, the present invention provides conductive CNTs electrode material whose electrical properties render them especially suitable for use in high efficiency rechargeable batteries. The present invention also provides methods for obtaining surface modified conductive CNT electrode materials comprising an array of individual linear, aligned CNTs having a uniform surface coating of an electrically conductive polymer such as polypyrrole, and their use in electrical energy storage devices.

  2. Laser-based coatings removal

    International Nuclear Information System (INIS)

    Freiwald, J.G.; Freiwald, D.

    1995-01-01

    Over the years as building and equipment surfaces became contaminated with low levels of uranium or plutonium dust, coats of paint were applied to stabilize the contaminants in place. Most of the earlier paint used was lead-based paint. More recently, various non-lead-based paints, such as two-part epoxy, are used. For D ampersand D (decontamination and decommissioning), it is desirable to remove the paints or other coatings rather than having to tear down and dispose of the entire building

  3. A study of strontium doped calcium phosphate coatings on AZ31

    International Nuclear Information System (INIS)

    Singh, Satish S.; Roy, Abhijit; Lee, Boeun E.; Ohodnicki, John; Loghmanian, Autrine; Banerjee, Ipsita; Kumta, Prashant N.

    2014-01-01

    Calcium phosphate (CaP) coatings have been studied to tailor the uncontrolled non-uniform corrosion of Mg based alloys while simultaneously enhancing bioactivity. The use of immersion techniques to deposit CaP coatings is attractive due to the ability of the approach to coat complex structures. In the current study, AZ31 substrates were subjected to various pretreatment conditions prior to depositing Sr 2+ doped and undoped CaP coatings. It was hypothesized that the bioactivity and corrosion protection of CaP coatings could be improved by doping with Sr 2+ . Heat treatment to elevated temperatures resulted in the diffusion of alloying elements, Mg and Zn, into the pretreated layer. Sr 2+ doped and undoped CaP coatings formed on the pretreated substrates consisted of biphasic mixtures of β-tricalcium phosphate (β-TCP) and hydroxyapatite (HA). Electrochemical corrosion experiments indicated that the extent of Sr 2+ doping and pretreatment both influenced the corrosion protection. Cytotoxicity was evaluated with MC3T3-E1 mouse preosteoblasts and human mesenchymal stem cells (hMSCs). For both cell types, proliferation decreased upon increasing the Sr 2+ concentration. However, both osteogenic gene and protein expression significantly increased upon increasing Sr 2+ concentration. These results suggest that Sr 2+ doped coatings are capable of promoting osteogenic differentiation on degradable Mg alloys, while also enhancing corrosion protection, in comparison to undoped CaP coatings

  4. Hydroxyapatite coating on damaged tooth surfaces by immersion

    International Nuclear Information System (INIS)

    Lim, Byoung-Ki; Ryu, Su-Chak; Sun, Fangfang; Koh, Kwangnak; Han, Dong-Wook; Lee, Jaebeom

    2009-01-01

    Hydroxyapatite (HAp) was coated on scratched areas of a human tooth and HAp disks by the immersion method in a HAp colloidal solution (≤20 μm of average diameter dispersed in DI water). The surface morphologies of the scratched area after immersion for 1-3 months were investigated showing that the damaged surfaces were remarkably recovered. Then, the mechanical property and chemical stability of the HAp coating layers on both specimens were determined via the Vickers hardness test and concentration measurement of extracted Ca 2+ ions, respectively, after strong acidic treatment. The cellular behavior of mouse calvaria-derived pre-osteoblastic cells (MC3T3-E1) was also examined on the HAp layers regenerated on micro-scratched HAp disks for the purpose of their potential applications on maxillofacial bone conservation and reconstruction for prosthetic dentistry, and artificial disk preparation of a vertebral column. The notable loss of Ca 2+ ions under a highly acidic condition was not observed in the layers coated by HAp adsorption, indicating that the coating surface was well adhered with the original surfaces of the respective specimen. Moreover, the HAp adsorption did not adversely affect the adhesion, growth and proliferation of MC3T3-E1 cells on the coated HAp layers for up to 21 days. These results suggest that the HAp coating on the scratched areas of the tooth would be effectively applicable for the development of long-term prevention of micro-cleavage and tooth health supporters to reduce discoloration and further maxillofacial and orthopedic applications.

  5. Aesthetic coatings for concrete bridge components

    Science.gov (United States)

    Kriha, Brent R.

    This thesis evaluated the durability and aesthetic performance of coating systems for utilization in concrete bridge applications. The principle objectives of this thesis were: 1) Identify aesthetic coating systems appropriate for concrete bridge applications; 2) Evaluate the performance of the selected systems through a laboratory testing regimen; 3) Develop guidelines for coating selection, surface preparation, and application. A series of site visits to various bridges throughout the State of Wisconsin provided insight into the performance of common coating systems and allowed problematic structural details to be identified. To aid in the selection of appropriate coating systems, questionnaires were distributed to coating manufacturers, bridge contractors, and various DOT offices to identify high performing coating systems and best practices for surface preparation and application. These efforts supplemented a literature review investigating recent publications related to formulation, selection, surface preparation, application, and performance evaluation of coating materials.

  6. Coated foams, preparation, uses and articles

    Science.gov (United States)

    Duchane, D.V.; Barthell, B.L.

    1982-10-21

    Hydrophobic cellular material is coated with a thin hydrophilic polymer skin which stretches tightly over the foam but which does not fill the cells of the foam, thus resulting in a polymer-coated foam structure having a smoothness which was not possible in the prior art. In particular, when the hydrophobic cellular material is a specially chosen hydrophobic polymer foam and is formed into arbitrarily chosen shapes prior to the coating with hydrophilic polymer, inertial confinement fusion (ICF) targets of arbitrary shapes can be produced by subsequently coating the shapes with metal or with any other suitable material. New articles of manufacture are produced, including improved ICF targets, improved integrated circuits, and improved solar reflectors and solar collectors. In the coating method, the cell size of the hydrophobic cellular material, the viscosity of the polymer solution used to coat, and the surface tension of the polymer solution used to coat are all very important to the coating.

  7. Hexagonal Boron Nitride Impregnated Silane Composite Coating for Corrosion Resistance of Magnesium Alloys for Temporary Bioimplant Applications

    Directory of Open Access Journals (Sweden)

    Saad Al-Saadi

    2017-11-01

    Full Text Available Magnesium and its alloys are attractive potential materials for construction of biodegradable temporary implant devices. However, their rapid degradation in human body fluid before the desired service life is reached necessitate the application of suitable coatings. To this end, WZ21 magnesium alloy surface was modified by hexagonal boron nitride (hBN-impregnated silane coating. The coating was chemically characterised by Raman spectroscopy. Potentiodynamic polarisation and electrochemical impedance spectroscopy (EIS of the coated alloy in Hanks’ solution showed a five-fold improvement in the corrosion resistance of the alloy due to the composite coating. Post-corrosion analyses corroborated the electrochemical data and provided a mechanistic insight of the improvement provided by the composite coating.

  8. Hydroxyapatite coatings deposited by liquid precursor plasma spraying: controlled dense and porous microstructures and osteoblastic cell responses

    International Nuclear Information System (INIS)

    Huang Yi; Song Lei; Liu Xiaoguang; Xiao Yanfeng; Wu Yao; Chen Jiyong; Wu Fang; Gu Zhongwei

    2010-01-01

    Hydroxyapatite coatings were deposited on Ti-6Al-4V substrates by a novel plasma spraying process, the liquid precursor plasma spraying (LPPS) process. X-ray diffraction results showed that the coatings obtained by the LPPS process were mainly composed of hydroxyapatite. The LPPS process also showed excellent control on the coating microstructure, and both nearly fully dense and highly porous hydroxyapatite coatings were obtained by simply adjusting the solid content of the hydroxyapatite liquid precursor. Scanning electron microscope observations indicated that the porous hydroxyapatite coatings had pore size in the range of 10-200 μm and an average porosity of 48.26 ± 0.10%. The osteoblastic cell responses to the dense and porous hydroxyapatite coatings were evaluated with human osteoblastic cell MG-63, in respect of the cell morphology, proliferation and differentiation, with the hydroxyapatite coatings deposited by the atmospheric plasma spraying (APS) process as control. The cell experiment results indicated that the heat-treated LPPS coatings with a porous structure showed the best cell proliferation and differentiation among all the hydroxyapatite coatings. Our results suggest that the LPPS process is a promising plasma spraying technique for fabricating hydroxyapatite coatings with a controllable microstructure, which has great potential in bone repair and replacement applications.

  9. Friction- and wear-reducing coating

    Science.gov (United States)

    Zhu, Dong [Farmington Hills, MI; Milner, Robert [Warren, MI; Elmoursi, Alaa AbdelAzim [Troy, MI

    2011-10-18

    A coating includes a first layer of a ceramic alloy and a second layer disposed on the first layer and including carbon. The coating has a hardness of from 10 to 20 GPa and a coefficient of friction of less than or equal to 0.12. A method of coating a substrate includes cleaning the substrate, forming the first layer on the substrate, and depositing the second layer onto the first layer to thereby coat the substrate.

  10. Functional coatings: the sol-gel approach

    International Nuclear Information System (INIS)

    Belleville, Ph.

    2010-01-01

    CEA's sol-gel laboratory is specialized in the development of innovative sol-gel optical coatings and has extended its application field to membrane materials and coatings for energy conversion, to electric coatings for microelectronics devices and to thin films for gas sensing. This article describes, by way of examples, the laboratory's research on sol-gel functional coatings, including nano-material synthesis, organic-inorganic hybrid-based solution preparation as well as deposition process development and prototyping. (author)

  11. Sputter coating of microspherical substrates by levitation

    Science.gov (United States)

    Lowe, A.T.; Hosford, C.D.

    Microspheres are substantially uniformly coated with metals or nonmetals by simltaneously levitating them and sputter coating them at total chamber pressures less than 1 torr. A collimated hole structure comprising a parallel array of upwardly projecting individual gas outlets is machined out to form a dimple. Glass microballoons,, which are particularly useful in laser fusion applications, can be substantially uniformly coated using the coating method and apparatus.

  12. Laser reflector with an interference coating

    International Nuclear Information System (INIS)

    Vol'pyan, O D; Semenov, A A; Yakovlev, P P

    1998-01-01

    An analysis was made of the reflectivity of interference coatings intended for the use in optical pumping of solid-state lasers. Ruby and Nd 3+ :YAG lasers were used as models in comparative pumping efficiency measurements, carried out employing reflectors with interference and silver coatings. Estimates of the service life of reflectors with interference coatings were obtained. The power of a thermo-optical lens was reduced by the use of such coatings in cw lasers. (laser system components)

  13. Absorptive coating for aluminum solar panels

    Science.gov (United States)

    Desmet, D.; Jason, A.; Parr, A.

    1979-01-01

    Method for coating forming coating of copper oxide from copper component of sheet aluminum/copper alloy provides strong durable solar heat collector panels. Copper oxide coating has solar absorption characteristics similar to black chrome and is much simpler and less costly to produce.

  14. Multispectral Image Analysis for Astaxanthin Coating Classification

    DEFF Research Database (Denmark)

    Ljungqvist, Martin Georg; Ersbøll, Bjarne Kjær; Nielsen, Michael Engelbrecht

    2012-01-01

    Industrial quality inspection using image analysis on astaxanthin coating in aquaculture feed pellets is of great importance for automatic production control. The pellets were divided into two groups: one with pellets coated using synthetic astaxanthin in fish oil and the other with pellets coated...

  15. ETV Program Report: Coatings for Wastewater Collection ...

    Science.gov (United States)

    The Standard Cement Materials, Inc. Standard Epoxy Coating 4553™ (SEC 4553) epoxy coating used for wastewater collection system rehabilitation was evaluated by EPA’s Environmental Technology Verification Program under laboratory conditions at the Center for Innovative Grouting Material and Technology (CIGMAT) Laboratory at the University of Houston. Testing was conducted over a period of six months to evaluate the coating’s (1) chemical resistance and (2) bonding strength for infrastructure applications. For chemical resistance, coated concrete and clay bricks with holidays (holes created in the coating) were used to evaluate the chemical resistance of the coating/substrate bond under a corrosive environment. Twenty coated concrete (dry and wet) and 20 coated clay brick (dry and wet) specimens were exposed to DI water and sulfuric acid solution (pH=1), and the specimens were visually inspected and weight changes measured. Evaluation of the coating-to-substrate bonding strength was determined using two modified ASTM test methods – one to determine bond strength of the coating with two specimens sandwiched together using the coating, and the second to determine the bond strength by applying a tensile load to the coating applied to specimens of each substrate. Forty-eight bonding tests were performed over the six month evaluation. The tests resulted in the following conclusions about Standard Cement’s SEC 4553 coating: • After the six-month chemi

  16. Study on nano-coating on uranium

    International Nuclear Information System (INIS)

    Zhang Yongbin; Xian Xiaobin; Lu Xuechao; Lang Dingmu; Li Kexue; Tang Kai

    2002-01-01

    The SiO 2 , TiO 2 coatings on uranium have been prepared by sol-gel method under different processes. By evaluating the coating quality with SEM, the optimal process parameters have been determined. Corrosion test shows that the coatings have anticorrosion property

  17. Latest Developments in PVD Coatings for Tooling

    Directory of Open Access Journals (Sweden)

    Gabriela Strnad

    2010-06-01

    Full Text Available The paper presents the recent developments in the field of PVD coating for manufacturing tools. A review of monoblock, multilayer, nanocomposite, DLC and oxinitride coatings is discussed, with the emphasis on coatings which enables the manufacturers to implement high productivity processes such as high speed cutting and dry speed machining.

  18. Method for coating substrates and mask holder

    NARCIS (Netherlands)

    Bijkerk, Frederik; Yakshin, Andrey; Louis, Eric; Kessels, M.J.H.; Maas, Edward Lambertus Gerardus; Bruineman, Caspar

    2004-01-01

    When coating substrates it is frequently desired that the layer thickness should be a certain function of the position on the substrate to be coated. To control the layer thickness a mask is conventionally arranged between the coating particle source and the substrate. This leads to undesirable

  19. Sonochemical coating of magnetite nanoparticles with silica.

    Science.gov (United States)

    Dang, Feng; Enomoto, Naoya; Hojo, Junichi; Enpuku, Keiji

    2010-01-01

    Magnetite nanoparticles were coated with silica through the hydrolysis and condensation of tetraethyl orthosilicate (TEOS) under ultrasonic irradiation. The ultrasonic irradiation was used to prevent the agglomeration of the magnetite particles and accelerate the hydrolysis and condensation of TEOS. TEM, DLS, XRF, VSM, TG and sedimentation test were used to characterize the silica-coated magnetite particles. The dispersibility of silica-coated magnetite particles in aqueous solution was improved significantly and the agglomerate particle size was decreased to 110 nm. It was found that the agglomerate particle size of silica-coated magnetite particles was mainly decided by the coating temperature and the pH value in the silica-coating process. The weight ratio of silica in silica-coated magnetite particles was mainly decided by the pH value in the silica-coating process. The dispersibility of silica-coated magnetite particles was mainly decided by the agglomerate particle size of the suspension. The oxidation of magnetite particles in air was limited through the coated silica. The magnetism of silica-coated magnetite particles decreased slightly after silica-coating.

  20. Amphiphilic copolymers for fouling-release coatings

    DEFF Research Database (Denmark)

    Noguer, Albert Camós; Olsen, Stefan Møller; Hvilsted, Søren

    of the coatings [9,10,11]. This work shows the effect of an amphiphilic copolymer that induces hydrophilicity on the surface of the silicone-based fouling release coatings. The behaviour of these copolymers within the coating upon immersion and the interaction of these surface-active additives with other...

  1. Modifications of optical properties with ceramic coatings

    International Nuclear Information System (INIS)

    Besmann, T.M.; Abdel-Latif, A.I.

    1990-01-01

    Coatings of ceramic materials that exhibited high thermal absorptivities and emissivities were chemical vapor deposited on graphite and refractory metals. In this paper the coatings prepared were SiC and B 4 C, and the substrates used were graphite, molybdenum, titanium, and Nb-1Zr. The coatings are characterized with regard to adherence, optical properties, and response to potential harsh environments

  2. Coat Hangers across the Curriculum

    Science.gov (United States)

    Kibble, Bob

    2012-01-01

    There are many ways in which wire coat hangers can be used other than for suspending clothes. The author has been making use of them in his teaching for many years--copying ideas from colleagues and creating some for himself. In this article, he shares five examples that can enrich learning about science. (Contains 6 figures.)

  3. Electron curing of surface coatings

    International Nuclear Information System (INIS)

    Nablo, S.V.

    1974-01-01

    The technical development of electron curing of surface coatings has received great impetus since 1970 from dramatic changes in the economics of the conventional thermal process. The most important of these changes are reviewed, including: the Clear Air Act, increasing cost and restrictive allocation of energy, decreased availability and increased costs of solvents, competitive pressure for higher line productivity. The principles of free-radical initiated curing as they pertain to industrial coatings are reviewed. Although such electron initiated processes have been under active development for at least two decades, high volume production applications on an industrial scale have only recently appeared. These installations are surveyed with emphasis on the developments in machinery and coatings which have made this possible. The most significant economic advantages of electron curing are presented. In particular, the ability of electron curing to eliminate substrate damage and to eliminate the curing station (oven) as the pacing element for most industrial surface coating curing applications is discussed. Examples of several new processes of particular interest in the textile industry are reviewed, including the curing of transfer cast urethane films, flock adhesives, and graftable surface finishes

  4. Polymer-coated quantum dots

    NARCIS (Netherlands)

    Tomczak, N.; Liu, Rongrong; Vancso, Gyula J.

    2013-01-01

    Quantum Dots (QDs) are semiconductor nanocrystals with distinct photophysical properties finding applications in biology, biosensing, and optoelectronics. Polymeric coatings of QDs are used primarily to provide long-term colloidal stability to QDs dispersed in solutions and also as a source of

  5. Industrial Coatings at Extreme Conditions

    DEFF Research Database (Denmark)

    Subramanian, Srinath; Pérez Hornero, Clara; Pedersen, Lars Thorslund

    With the gradual depletion of oil wells operable at relatively lower temperatures and pressures, the upstream oil industry relies on High Pressure High Temperature (HPHT) wells to source crude oil and gas. HPHT well extraction and processing require anticorrosive coatings applied on substrates...

  6. Water transport in multilayer coatings

    NARCIS (Netherlands)

    Baukh, V.

    2012-01-01

    Coatings form the interface between structures and the environment in many application domains. They play a crucial role in providing protection, e.g. against corrosion, they form a barrier against an aggressive environment and they create the aesthetic appearance. To fulfill such functionalities,

  7. RBS and XPS analyses of the composite calcium phosphate coatings for biomedical applications

    International Nuclear Information System (INIS)

    Ide-Ektessabi, Ari; Yamaguchi, Tetsuro; Tanaka, Yoshikazu

    2005-01-01

    The calcium phosphate coatings on metallic implants are widely used for biomedical applications. The calcium phosphate coatings require mechanical strength, strong adhesion to the metallic implants, chemical stability and low dissolution into the human body fluid for stable functioning in the corrosive environment of the human body. In this study, a novel approach for improving the calcium phosphate coatings is utilized by adding trace metallic element into the coatings. We focused on teeth enamel, which is the hardest calcium phosphate tissue in the human body. Zn concentration increases exponentially from the interior to the surface of the enamel. As the Zn concentration increases, so the local hardness increases. Our previous studies suggest that Zn has influence on the hardness and other properties of enamel, calcium phosphate tissue. Calcium phosphate coatings doped with Zn was fabricated and characterized. The atomic composition and chemical state were investigated by using Rutherford backscattering spectroscopy (RBS) and X-ray photoelectron spectrometer (XPS), respectively. Scratch test was also carried out for measuring the adhesion of the coatings

  8. UNDERWATER COATINGS FOR CONTAMINATION CONTROL

    International Nuclear Information System (INIS)

    Julia L. Tripp; Kip Archibald; Ann Marie Phillips; Joseph Campbell

    2004-01-01

    The Idaho National Laboratory (INL) deactivated several aging nuclear fuel storage basins. Planners for this effort were greatly concerned that radioactive contamination present on the basin walls could become airborne as the sides of the basins became exposed during deactivation and allowed to dry after water removal. One way to control this airborne contamination was to fix the contamination in place while the pool walls were still submerged. There are many underwater coatings available on the market for marine, naval and other applications. A series of tests were run to determine whether the candidate underwater fixatives were easily applied and adhered well to the substrates (pool wall materials) found in INL fuel pools. Lab-scale experiments were conducted by applying fourteen different commercial underwater coatings to four substrate materials representative of the storage basin construction materials, and evaluating their performance. The coupons included bare concrete, epoxy painted concrete, epoxy painted carbon steel, and stainless steel. The evaluation criteria included ease of application, adherence to the four surfaces of interest, no change on water clarity or chemistry, non-hazardous in final applied form and be proven in underwater applications. A proprietary two-part, underwater epoxy owned by S. G. Pinney and Associates was selected from the underwater coatings tested for application to all four pools. Divers scrubbed loose contamination off the basin walls and floors using a ship hull scrubber and vacuumed up the sludge. The divers then applied the coating using a special powered roller with two separate heated hoses that allowed the epoxy to mix at the roller surface was used to eliminate pot time concerns. The walls were successfully coated and water was removed from the pools with no detectable airborne contamination releases

  9. Atomically Bonded Transparent Superhydrophobic Coatings

    Energy Technology Data Exchange (ETDEWEB)

    Aytug, Tolga [ORNL

    2015-08-01

    Maintaining clarity and avoiding the accumulation of water and dirt on optically transparent surfaces such as US military vehicle windshields, viewports, periscope optical head windows, and electronic equipment cover glasses are critical to providing a high level of visibility, improved survivability, and much-needed safety for warfighters in the field. Through a combination of physical vapor deposition techniques and the exploitation of metastable phase separation in low-alkali borosilicate, a novel technology was developed for the fabrication of optically transparent, porous nanostructured silica thin film coatings that are strongly bonded to glass platforms. The nanotextured films, initially structurally superhydrophilic, exhibit superior superhydrophobicity, hence antisoiling ability, following a simple but robust modification in surface chemistry. The surfaces yield water droplet contact angles as high as 172°. Moreover, the nanostructured nature of these coatings provides increased light scattering in the UV regime and reduced reflectivity (i.e., enhanced transmission) over a broad range of the visible spectrum. In addition to these functionalities, the coatings exhibit superior mechanical resistance to abrasion and are thermally stable to temperatures approaching 500°C. The overall process technology relies on industry standard equipment and inherently scalable manufacturing processes and demands only nontoxic, naturally abundant, and inexpensive base materials. Such coatings, applied to the optical components of current and future combat equipment and military vehicles will provide a significant strategic advantage for warfighters. The inherent self-cleaning properties of such superhydrophobic coatings will also mitigate biofouling of optical windows exposed to high-humidity conditions and can help decrease repair/replacement costs, reduce maintenance, and increase readiness by limiting equipment downtime.

  10. Ultrasonic tests on materials with protective coatings

    International Nuclear Information System (INIS)

    Whaley, H.L.

    1977-01-01

    Protective coatings are applied to some nuclear components such as reactor vessels to inhibit surface corrosion. Since in-service ultrasonic inspection is required for such components, a study was performed to determine whether the use of protective coatings can affect ultrasonic tests. Two 2 in. thick steel plates were uniformly machined, sandblasted, and used as bases for two types of protective coatings. The type and thickness of the coating and the presence of contamination, such as fingerprints or mild oxidation under the paint, were the independent variables associated with the coating. Tests were run to determine the effects of the protective coatings on ultrasonic tests conducted on the steel plates. Significant variations in ultrasonic test sensitivity occurred as a function of the type and thickness of protective coating, couplant (material that conducts the ultrasound from the transducer into the test part, normally water or some type of oil), transducer wear plate, and ultrasonic test frequency. Ultrasonic tests can be strongly affected by a protective coating on the component to be inspected. As compared to the test sensitivity for an uncoated reference sample, the sensitivity may be dramatically shifted up or down on the coated surface. In certain coating thickness ranges, the sensitivity can fluctuate widely with small changes in coating thickness. If a coating is chosen properly, however, components with protective coatings can be tested ultrasonically with valid results. These results are for the case of ultrasonic input on the coated surface. It is not expected that an ultrasonic test conducted from the front surface would be appreciably affected by a coating on the rear surface

  11. Preparation of sustained release capsules by electrostatic dry powder coating, using traditional dip coating as reference.

    Science.gov (United States)

    Yang, Yan; Shen, Lian; Yuan, Feng; Fu, Hui; Shan, Weiguang

    2018-05-30

    Lately, a great deal of attention is being paid to capsule coating, since the coat protects active pharmaceutical ingredients (APIs) from damage, as is in the case of tablet and pellet. However, moisture and heat sensitivity of gelatin shells make it challenging to coat capsules using the conventional aqueous coating techniques. In an effort to overcome this challenge, the present study aims to coat capsules using two different coating techniques: electrostatic dry powder coating (EDPC) and dip coating (DC). Both capsule coatings and free films were prepared by these two coating techniques, and the effects of coating formulations and processing conditions on the film quality were investigated. The corresponding drug in vitro release and mechanisms were characterized and compared. The results of dissolution tests demonstrated that the drug release behavior of both EDPC and DC coated capsules could be optimized to a sustained release of 24 h, following the Fick's diffusion law. The results of this study suggest that EDPC method is better than DC method for coating capsules, with respect to the higher production efficiency and better stability, indicating that this dry coating technology has promised in gelatin capsule coating applications. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Levitation, coating, and transport of particulate materials

    International Nuclear Information System (INIS)

    Hendricks, C.D.

    1981-01-01

    Several processes in various fields require uniformly thick coatings and layers on small particles. The particles may be used as carriers of catalytic materials (platinum or other coatings), as laser fusion targets (various polymer or metallic coatings), or for biological or other tracer or interactive processes. We have devised both molecular beam and electro-dynamic techniques for levitation of the particles during coating and electrodynamic methods of controlling and transporting the particles between coating steps and to final use locations. Both molecular beam and electrodynamic techniques are described and several advantages and limitations of each will be discussed. A short movie of an operating electrodynamic levitation and transport apparatus will be shown

  13. Coatings for fast breeder reactor components

    International Nuclear Information System (INIS)

    Johnson, R.N.

    1984-04-01

    Several types of metallurgical coatings are used in the unique environments of the fast breeder reactor. Most of the coatings have been developed for tribological applications, but some also serve as corrosion barriers, diffusion barriers, or radionuclide traps. The materials that have consistently given the best performance as tribological coatings in the breeder reactor environments have been coatings based on chromium carbide, nickel aluminide, or Tribaloy 700 (a nickel-base hard-facing alloy). Other coatings that have been qualified for limited applications include chromium plating for low temperature galling protection and nickel plating for radionuclide trapping

  14. Transparent nanocrystalline diamond coatings and devices

    Science.gov (United States)

    Sumant, Anirudha V.; Khan, Adam

    2017-08-22

    A method for coating a substrate comprises producing a plasma ball using a microwave plasma source in the presence of a mixture of gases. The plasma ball has a diameter. The plasma ball is disposed at a first distance from the substrate and the substrate is maintained at a first temperature. The plasma ball is maintained at the first distance from the substrate, and a diamond coating is deposited on the substrate. The diamond coating has a thickness. Furthermore, the diamond coating has an optical transparency of greater than about 80%. The diamond coating can include nanocrystalline diamond. The microwave plasma source can have a frequency of about 915 MHz.

  15. Evaluation of irradiated coating material specimens

    International Nuclear Information System (INIS)

    Lee, Yong Jin; Nam, Seok Woo; Cho, Lee Moon

    2007-12-01

    Evaluation result of irradiated coating material specimens - Coating material specimens radiated Gamma Energy(Co 60) in air condition. - Evaluation conditions was above 1 X 10 4 Gy/hr, and radiated TID 2.0 X 10 6 Gy. - The radiated coating material specimens, No Checking, Cracking, Flaking, Delamination, Peeling and Blistering. - Coating system at the Kori no. 1 and APR 1400 Nuclear power plant, evaluation of irradiated coating materials is in accordance with owner's requirement(2.0 X 10 6 Gy)

  16. Statistical experimental design for refractory coatings

    International Nuclear Information System (INIS)

    McKinnon, J.A.; Standard, O.C.

    2000-01-01

    The production of refractory coatings on metal casting moulds is critically dependent on the development of suitable rheological characteristics, such as viscosity and thixotropy, in the initial coating slurry. In this paper, the basic concepts of mixture design and analysis are applied to the formulation of a refractory coating, with illustration by a worked example. Experimental data of coating viscosity versus composition are fitted to a statistical model to obtain a reliable method of predicting the optimal formulation of the coating. Copyright (2000) The Australian Ceramic Society

  17. Biological influence of Ca/P ratio on calcium phosphate coatings by sol-gel processing

    Energy Technology Data Exchange (ETDEWEB)

    Catauro, M., E-mail: michelina.catauro@unina2.it [Department of Industrial and Information Engineering, Second University of Naples, Via Roma 29 (Italy); Papale, F. [Department of Industrial and Information Engineering, Second University of Naples, Via Roma 29 (Italy); Sapio, L.; Naviglio, S. [Department of Biochemistry, Biophysics and General Pathology, Second University of Naples, Via L. De Crecchio 7, 80138 Naples (Italy)

    2016-08-01

    The objective of this work has been to develop low temperature sol-gel glass coatings to modify the substrate surface and to evaluate their bioactivity and biocompatibility. Glasses, based on SiO{sub 2}·CaO·P{sub 2}O{sub 5}, were synthesized by the sol-gel technique using tetraethyl orthosilicate, calcium nitrate tetrahydrate and triethyl phosphate as precursors of SiO{sub 2}, CaO and P{sub 2}O{sub 5}, respectively. Those materials, still in the sol phase, have been used to coat substrates by means of the dip-coating technique. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) has been used for characterize coatings and a microstructural analysis has been obtained using scanning electron microscopy (SEM). The potential applications of the coatings in the biomedical field were evaluated by bioactivity and biocompatibility tests. The coated substrate was immersed in simulated body fluid (SBF) for 21 days and the hydroxyapatite deposition on its surface was subsequently evaluated via SEM-EDXS analysis, as an index of bone-bonding capability. In order to study the cell behavior and response to our silica based materials, prepared via the sol-gel method, with various Ca/P ratio and coating substrate, we have used the human osteoblast-like U2OS cell line. - Highlights: • Coatings consisting of SiO{sub 2}·CaO·P{sub 2}O{sub 5} glasses were prepared via sol-gel dip coating. • Ca/P molar ratio affects the film morphology and biocompatibility. • Higher cell proliferation was found in response to higher Ca/P ratios coatings. • A growth cell proliferation inhibition was observed in response to lower Ca/P ratio.

  18. Mechanical, degradation and cytocompatibility properties of magnesium coated phosphate glass fibre reinforced polycaprolactone composites.

    Science.gov (United States)

    Liu, Xiaoling; Hasan, Muhammad S; Grant, David M; Harper, Lee T; Parsons, Andrew J; Palmer, Graham; Rudd, Chris D; Ahmed, Ifty

    2014-11-01

    Retention of mechanical properties of phosphate glass fibre reinforced degradable polyesters such as polycaprolactone and polylactic acid in aqueous media has been shown to be strongly influenced by the integrity of the fibre/polymer interface. A previous study utilising 'single fibre' fragmentation tests found that coating with magnesium improved the fibre and matrix interfacial shear strength. Therefore, the aim of this study was to investigate the effects of a magnesium coating on the manufacture and characterisation of a random chopped fibre reinforced polycaprolactone composite. Short chopped strand non-woven phosphate glass fibre mats were sputter coated with degradable magnesium to manufacture phosphate glass fibre/polycaprolactone composites. The degradation behaviour (water uptake, mass loss and pH change of the media) of these polycaprolactone composites as well as of pure polycaprolactone was investigated in phosphate buffered saline. The Mg coated fibre reinforced composites revealed less water uptake and mass loss during degradation compared to the non-coated composites. The cations released were also explored and a lower ion release profile for all three cations investigated (namely Na(+), Mg(2+) and Ca(2+)) was seen for the Mg coated composite samples. An increase of 17% in tensile strength and 47% in tensile modulus was obtained for the Mg coated composite samples. Both flexural and tensile properties were investigated and a higher retention of mechanical properties was obtained for the Mg coated fibre reinforced composite samples up to 10 days immersion in PBS. Cytocompatibility study showed both composite samples (coated and non-coated) had good cytocompatibility with human osteosarcoma cell line. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  19. A Multifunctional Coating for Autonomous Corrosion Control

    Science.gov (United States)

    Calle, Luz M.; Li, Wenyan; Buhrow, Jerry W.; Jolley, Scott t.

    2011-01-01

    Nearly all metals and their alloys are subject to corrosion that causes them to lose their structural integrity or other critical functionality. Protective coatings are the most commonly used method of corrosion control. However, progressively stricter environmental regulations have resulted in the ban of many commercially available corrosion protective coatings due to the harmful effects of their solvents or corrosion inhibitors. This work concerns the development of a multifunctional smart coating for the autonomous control of corrosion. This coating is being developed to have the inherent ability to detect the chemical changes associated with the onset of corrosion and respond autonomously to indicate it and control it. The multi-functionality of the coating is based on microencapsulation technology specifically designed for corrosion control applications. This design has, in addition to all the advantages of existing microcapsulation designs, the corrosion controlled release function that triggers the delivery of corrosion indicators and inhibitors on demand, only when and where needed. Microencapsulation of self-healing agents for autonomous repair of mechanical damage to the coating is also being pursued. Corrosion indicators, corrosion inhibitors, as well as self-healing agents, have been encapsulated and dispersed into several paint systems to test the corrosion detection, inhibition, and self-healing properties of the coating. Key words: Corrosion, coating, autonomous corrosion control, corrosion indication, corrosion inhibition, self-healing coating, smart coating, multifunctional coating, microencapsulation.

  20. Black molecular adsorber coatings for spaceflight applications

    Science.gov (United States)

    Abraham, Nithin S.; Hasegawa, Mark M.; Straka, Sharon A.

    2014-09-01

    The molecular adsorber coating is a new technology that was developed to mitigate the risk of on-orbit molecular contamination on spaceflight missions. The application of this coating would be ideal near highly sensitive, interior surfaces and instruments that are negatively impacted by outgassed molecules from materials, such as plastics, adhesives, lubricants, epoxies, and other similar compounds. This current, sprayable paint technology is comprised of inorganic white materials made from highly porous zeolite. In addition to good adhesion performance, thermal stability, and adsorptive capability, the molecular adsorber coating offers favorable thermal control characteristics. However, low reflectivity properties, which are typically offered by black thermal control coatings, are desired for some spaceflight applications. For example, black coatings are used on interior surfaces, in particular, on instrument baffles for optical stray light control. Similarly, they are also used within light paths between optical systems, such as telescopes, to absorb light. Recent efforts have been made to transform the white molecular adsorber coating into a black coating with similar adsorptive properties. This result is achieved by optimizing the current formulation with black pigments, while still maintaining its adsorption capability for outgassing control. Different binder to pigment ratios, coating thicknesses, and spray application techniques were explored to develop a black version of the molecular adsorber coating. During the development process, coating performance and adsorption characteristics were studied. The preliminary work performed on black molecular adsorber coatings thus far is very promising. Continued development and testing is necessary for its use on future contamination sensitive spaceflight missions.

  1. Solar Absorptance of Cermet Coatings Evaluated

    Science.gov (United States)

    Jaworske, Donald A.

    2004-01-01

    Cermet coatings, molecular mixtures of metal and ceramic, are being considered for the heat inlet surface of solar Stirling convertors. In this application, the key role of the cermet coating is to absorb as much of the incident solar energy as possible. To achieve this objective, the cermet coating has a high solar absorptance value. Cermet coatings are manufactured utilizing sputter deposition, and many different metal and ceramic combinations can be created. The ability to mix metal and ceramic at the atomic level offers the opportunity to tailor the composition, and hence, the optical properties of these coatings. The NASA Glenn Research Center has prepared and characterized a wide variety of cermet coatings utilizing different metals deposited in an aluminum oxide ceramic matrix. In addition, the atomic oxygen durability of these coatings has been evaluated.

  2. Armor systems including coated core materials

    Science.gov (United States)

    Chu, Henry S [Idaho Falls, ID; Lillo, Thomas M [Idaho Falls, ID; McHugh, Kevin M [Idaho Falls, ID

    2012-07-31

    An armor system and method involves providing a core material and a stream of atomized coating material that comprises a liquid fraction and a solid fraction. An initial layer is deposited on the core material by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is less than the liquid fraction of the stream of atomized coating material on a weight basis. An outer layer is then deposited on the initial layer by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is greater than the liquid fraction of the stream of atomized coating material on a weight basis.

  3. Electrical contact arrangement for a coating process

    Science.gov (United States)

    Kabagambe, Benjamin; McCamy, James W; Boyd, Donald W

    2013-09-17

    A protective coating is applied to the electrically conductive surface of a reflective coating of a solar mirror by biasing a conductive member having a layer of a malleable electrically conductive material, e.g. a paste, against a portion of the conductive surface while moving an electrodepositable coating composition over the conductive surface. The moving of the electrodepositable coating composition over the conductive surface includes moving the solar mirror through a flow curtain of the electrodepositable coating composition and submerging the solar mirror in a pool of the electrodepositable coating composition. The use of the layer of a malleable electrically conductive material between the conductive member and the conductive surface compensates for irregularities in the conductive surface being contacted during the coating process thereby reducing the current density at the electrical contact area.

  4. Electrostatic coating technologies for food processing.

    Science.gov (United States)

    Barringer, Sheryl A; Sumonsiri, Nutsuda

    2015-01-01

    The application of electrostatics in both powder and liquid coating can improve the quality of food, such as its appearance, aroma, taste, and shelf life. Coatings can be found most commonly in the snack food industry, as well as in confectionery, bakery, meat and cheese processing. In electrostatic powder coating, the most important factors influencing coating quality are powder particle size, density, flowability, charge, and resistivity, as well as the surface properties and characteristics of the target. The most important factors during electrostatic liquid coating, also known as electrohydrodynamic coating, include applied voltage and electrical resistivity and viscosity of the liquid. A good understanding of these factors is needed for the design of optimal coating systems for food processing.

  5. Nanocomposite Coatings: Preparation, Characterization, Properties, and Applications

    Directory of Open Access Journals (Sweden)

    Phuong Nguyen-Tri

    2018-01-01

    Full Text Available Incorporation of nanofillers into the organic coatings might enhance their barrier performance, by decreasing the porosity and zigzagging the diffusion path for deleterious species. Thus, the coatings containing nanofillers are expected to have significant barrier properties for corrosion protection and reduce the trend for the coating to blister or delaminate. On the other hand, high hardness could be obtained for metallic coatings by producing the hard nanocrystalline phases within a metallic matrix. This article presents a review on recent development of nanocomposite coatings, providing an overview of nanocomposite coatings in various aspects dealing with the classification, preparative method, the nanocomposite coating properties, and characterization methods. It covers potential applications in areas such as the anticorrosion, antiwear, superhydrophobic area, self-cleaning, antifouling/antibacterial area, and electronics. Finally, conclusion and future trends will be also reported.

  6. Nanostructured thin films and coatings mechanical properties

    CERN Document Server

    2010-01-01

    The first volume in "The Handbook of Nanostructured Thin Films and Coatings" set, this book concentrates on the mechanical properties, such as hardness, toughness, and adhesion, of thin films and coatings. It discusses processing, properties, and performance and provides a detailed analysis of theories and size effects. The book presents the fundamentals of hard and superhard nanocomposites and heterostructures, assesses fracture toughness and interfacial adhesion strength of thin films and hard nanocomposite coatings, and covers the processing and mechanical properties of hybrid sol-gel-derived nanocomposite coatings. It also uses nanomechanics to optimize coatings for cutting tools and explores various other coatings, such as diamond, metal-containing amorphous carbon nanostructured, and transition metal nitride-based nanolayered multilayer coatings.

  7. ANTIREFLECTION MULTILAYER COATINGS WITH THIN METAL LAYERS

    Directory of Open Access Journals (Sweden)

    L. A. Gubanova

    2016-03-01

    Full Text Available The design of anti-reflective coatings for metal surfaces of Al, Ti, N,i Cr is proposed. The coatings have the form of alternating layers of dielectric/metal/dielectric with the number of cells up to15. The method of calculation of such coatings is proposed. We have calculated the coatings of the type [HfO2/Cr/HfO2]15, [ZrO2/Ti/Al2O3]15, [ZrO2/Cr/ZrO2]15. It is shown that the proposed interference coatings provide reduction of the residual reflectance of the metal several times (from 3.5 to 6.0 in a wide spectral range (300-1000 nm. The proposed coatings can be recommended as anti-reflective coatings for energy saving solar systems and batteries, and photovoltaic cells.

  8. Wear performance of laser processed tantalum coatings

    Energy Technology Data Exchange (ETDEWEB)

    Dittrick, Stanley; Balla, Vamsi Krishna; Bose, Susmita; Bandyopadhyay, Amit, E-mail: amitband@wsu.edu

    2011-12-01

    This first generation investigation evaluates the in vitro tribological performance of laser-processed Ta coatings on Ti for load-bearing implant applications. Linear reciprocating wear tests in simulated body fluid showed one order of magnitude less wear rate, of the order of 10{sup -4} mm{sup 3}(N.m){sup -1}, for Ta coatings compared to Ti. Our results demonstrate that Ta coatings can potentially minimize the early-stage bone-implant interface micro-motion induced wear debris generation due to their excellent bioactivity comparable to that of hydroxyapatite (HA), high wear resistance and toughness compared to popular HA coatings. Highlights: {yields} In vitro wear performance of laser processed Ta coatings on Ti was evaluated. {yields} Wear tests in SBF showed one order of magnitude less wear for Ta coatings than Ti. {yields} Ta coatings can minimize early-stage micro-motion induced wear debris generation.

  9. High efficiency turbine blade coatings

    Energy Technology Data Exchange (ETDEWEB)

    Youchison, Dennis L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gallis, Michail A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-06-01

    The development of advanced thermal barrier coatings (TBCs) of yttria stabilized zirconia (YSZ) that exhibit lower thermal conductivity through better control of electron beam - physical vapor deposition (EB-PVD) processing is of prime interest to both the aerospace and power industries. This report summarizes the work performed under a two-year Lab-Directed Research and Development (LDRD) project (38664) to produce lower thermal conductivity, graded-layer thermal barrier coatings for turbine blades in an effort to increase the efficiency of high temperature gas turbines. This project was sponsored by the Nuclear Fuel Cycle Investment Area. Therefore, particular importance was given to the processing of the large blades required for industrial gas turbines proposed for use in the Brayton cycle of nuclear plants powered by high temperature gas-cooled reactors (HTGRs). During this modest (~1 full-time equivalent (FTE)) project, the processing technology was developed to create graded TBCs by coupling ion beam-assisted deposition (IBAD) with substrate pivoting in the alumina-YSZ system. The Electron Beam - 1200 kW (EB-1200) PVD system was used to deposit a variety of TBC coatings with micron layered microstructures and reduced thermal conductivity below 1.5 W/m.K. The use of IBAD produced fully stoichiometric coatings at a reduced substrate temperature of 600°C and a reduced oxygen background pressure of 0.1 Pa. IBAD was also used to successfully demonstrate the transitioning of amorphous PVD-deposited alumina to the -phase alumina required as an oxygen diffusion barrier and for good adhesion to the substrate Ni2Al3 bondcoat. This process replaces the time consuming thermally grown oxide formation required before the YSZ deposition. In addition to the process technology, Direct Simulation Monte Carlo plume modeling and spectroscopic characterization of the PVD plumes were performed. The project consisted of five tasks. These included the

  10. Wrinkling of solidifying polymeric coatings

    Science.gov (United States)

    Basu, Soumendra Kumar

    2005-07-01

    In coatings, wrinkles are viewed as defects or as desired features for low gloss, and texture. In either case, discovering the origin of wrinkles and the conditions that lead to their formation is important. This research examines what wrinkling requires and proposes a mechanism to explain the observations. All curing wrinkling coatings contain multi-functional reactants. Upon curing, all develop a depth-wise gradient in solidification that result in a cross-linked elastic skin atop a viscous bottom layer. It is hypothesized that compressive stress develops in the skin when liquid below diffuses up into the skin. High enough compressive stress buckles the skin to produce wrinkles. The hypothesis is substantiated by experimental and theoretical evidences. Effects of various application and compositional parameters on wrinkle size in a liquid-applied acrylic coating and a powder-applied epoxy coating were examined. All three components, namely resin, cross-linker and catalyst blocked with at least equimolar volatile blocker, proved to be required for wrinkling. The wrinkling phenomenon was modeled with a theory that accounts for gradient generation, cross-linking reaction and skinning; predictions compared well with observations. Two-layer non-curing coatings that have a stiff elastic layer atop a complaint elastic bottom layer wrinkled when the top layer is compressed. The top layer was compressed by either moisture absorption or differential thermal expansion. Experimental observations compared well with predictions from a theory based on force balance in multilayer systems subjected to differential contraction or expansion. A model based on the Flory-Rehner free energy of a constrained cross-linked gel was constructed that predicts the compressive stress generated in a coating when it absorbs solvent. Linear stability analysis predicts that when a compressed elastic layer is attached atop a viscous layer, it is always unstable to buckles whose wavelength exceeds a

  11. First-in-human evaluation of a bioabsorbable polymer-coated sirolimus-eluting stent: imaging and clinical results of the DESSOLVE I Trial (DES with sirolimus and a bioabsorbable polymer for the treatment of patients with de novo lesion in the native coronary arteries).

    Science.gov (United States)

    Ormiston, John; Webster, Mark; Stewart, James; Vrolix, Mathias; Whitbourn, Robert; Donohoe, Dennis; Knape, Charlene; Lansky, Alexandra; Attizzani, Guilherme F; Fitzgerald, Peter; Kandzari, David E; Wijns, William

    2013-10-01

    This first-in-human multicenter study sought to examine prospectively the safety and efficacy of a new, cobalt chromium thin-strut, coronary absorbable polymer-coated, sirolimus-eluting stent. Bioabsorbable polymers on drug-eluting stents may lower the long-term risks of inflammation, delayed healing, and adverse events. We enrolled patients with symptomatic coronary artery disease with stable or unstable angina pectoris and >50% diameter stenosis, amenable to coverage with a ≤23-mm long stent in a vessel 2.5 to 3.5 mm in diameter. All patients received dual antiplatelet therapy after implantation. Patients, in groups of 10, underwent repeat angiography, intravascular ultrasound, and optical coherence tomography at 4, 6, or 8 months, and all patients were seen or contacted at 18 months of follow-up. The median (range) in-stent late lumen loss (LLL) was 0.03 mm (-0.22 to 0.21 mm), 0.10 mm (-0.03 to 1.2 mm), and 0.08 mm (-0.01 to 0.28 mm), at 4, 6, and 8 months, respectively. At 18 months, the median in-stent LLL was 0.08 mm (-0.30 to 0.46 mm). On optical coherence tomography, the proportion of uncovered stent struts decreased from a median of 7.3% (range 0.4% to 46.3%) at 4 months to 0% (range: 0% to 3.4%) at 18 months. The percentage of neointimal volume obstruction by intravascular ultrasound increased from a median of 5.3% to 9.1% between 4 and 6 months and remained nearly unchanged thereafter through 18 months of follow-up. The only recorded major adverse cardiac event was a myocardial infarction. At 18 months of follow-up, this absorbable polymer-coated, cobalt chromium sirolimus-eluting stent was associated with a low and stable in-stent LLL, complete strut coverage, and no stent thrombosis. (First-In-Human Trial of the MiStent Drug-Eluting Stent [DES] in Coronary Artery Disease [DESSOLVE-I]; NCT01247428). Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  12. Development and electrochemical characterization of Ni‐P coated tungsten incorporated electroless nickel coatings

    Energy Technology Data Exchange (ETDEWEB)

    Shibli, S.M.A., E-mail: smashibli@yahoo.com; Chinchu, K.S.

    2016-08-01

    Ni‐P-W alloy and composite coatings were prepared by incorporation of sodium tungstate/tungsten and Ni‐P coated tungsten into electroless nickel bath respectively. Good inter-particle interactions among the depositing elements i.e. Ni and P with the incorporating tungsten particles were achieved by means of pre-coated tungsten particle by electroless nickel covering prior to its addition into the electroless bath. The pre-coated tungsten particles got incorporated uniformly into the Ni-P matrix of the coating. The particles and the coatings were characterized at different stages by different techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The electroless Ni-P coating incorporated with pre-coated tungsten exhibited considerably high hardness, thickness and deposition rate. The performance and corrosion resistance characteristics of the composite coating incorporated with the nickel coated tungsten were found to be superior over other conventional Ni-P-W ternary alloy coatings currently reported. - Highlights: • An amorphous Ni-P coating was effectively formed on tungsten particles. • Electroless ternary Ni-P-W composite coatings were successfully prepared. • Enhancement in the inter-particle interaction in the Ni-P composite matrix was achieved. • Efficient and uniform incorporation of the composite in the internal layer was evident. • The tungsten incorporated coating possessed effective barrier protection.

  13. Multiphase-Multifunctional Ceramic Coatings

    Science.gov (United States)

    2013-06-30

    systems for high temperatura applications” “ Estudios de Ferroelasticidad en Sistemas Cerámicos Multifásicos para Aplicaciones en Alta Temperatura ...Ceramic Coatings Performing Organization names: Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional – Unidad Queretaro...materials, Cinvestav. Thesis: “Ferroelasticity studies in multiphase ceramic systems for high temperatura applications”. Her work mainly focused in the

  14. Beryllium coating on Inconel tiles

    International Nuclear Information System (INIS)

    Bailescu, V.; Burcea, G.; Lungu, C.P.; Mustata, I.; Lungu, A.M.; Rubel, M.; Coad, J.P.; Matthews, G.; Pedrick, L.; Handley, R.

    2007-01-01

    Full text of publication follows: The Joint European Torus (JET) is a large experimental nuclear fusion device. Its aim is to confine and study the behaviour of plasma in conditions and dimensions approaching those required for a fusion reactor. The plasma is created in the toroidal shaped vacuum vessel of the machine in which it is confined by magnetic fields. In preparation for ITER a new ITER-like Wall (ILW) will be installed on Joint European Torus (JET), a wall not having any carbon facing the plasma [1]. In places Inconel tiles are to be installed, these tiles shall be coated with Beryllium. MEdC represented by the National Institute for Laser, Plasma and Radiation Physics, Magurele, Bucharest and in direct cooperation with Nuclear Fuel Plant Pitesti started to coat Inconel tiles with 8 μm of Beryllium in accordance with the requirements of technical specification and fit for installation in the JET machine. This contribution provides an overview of the principles of manufacturing processes using thermal evaporation method in vacuum and the properties of the prepared coatings. The optimization of the manufacturing process (layer thickness, structure and purity) has been carried out on Inconel substrates (polished and sand blasted) The results of the optimization process and analysis (SEM, TEM, XRD, Auger, RBS, AFM) of the coatings will be presented. Reference [1] Takeshi Hirai, H. Maier, M. Rubel, Ph. Mertens, R. Neu, O. Neubauer, E. Gauthier, J. Likonen, C. Lungu, G. Maddaluno, G. F. Matthews, R. Mitteau, G. Piazza, V. Philipps, B. Riccardi, C. Ruset, I. Uytdenhouwen, R and D on full tungsten divertor and beryllium wall for JET TIER-like Wall Project, 24. Symposium on Fusion Technology - 11-15 September 2006 -Warsaw, Poland. (authors)

  15. Chrome - Free Aluminum Coating System

    Science.gov (United States)

    Bailey, John H.; Gugel, Jeffrey D.

    2010-01-01

    This slide presentation concerns the program to qualify a chrome free coating for aluminum. The program was required due to findings by OSHA and EPA, that hexavalent chromium, used to mitigate corrosion in aerospace aluminum alloys, poses hazards for personnel. This qualification consisted of over 4,000 tests. The tests revealed that a move away from Cr+6, required a system rather than individual components and that the maximum corrosion protection required pretreatment, primer and topcoat.

  16. High temperature solar selective coatings

    Science.gov (United States)

    Kennedy, Cheryl E

    2014-11-25

    Improved solar collectors (40) comprising glass tubing (42) attached to bellows (44) by airtight seals (56) enclose solar absorber tubes (50) inside an annular evacuated space (54. The exterior surfaces of the solar absorber tubes (50) are coated with improved solar selective coatings {48} which provide higher absorbance, lower emittance and resistance to atmospheric oxidation at elevated temperatures. The coatings are multilayered structures comprising solar absorbent layers (26) applied to the meta surface of the absorber tubes (50), typically stainless steel, topped with antireflective Savers (28) comprising at least two layers 30, 32) of refractory metal or metalloid oxides (such as titania and silica) with substantially differing indices of refraction in adjacent layers. Optionally, at least one layer of a noble metal such as platinum can be included between some of the layers. The absorbent layers cars include cermet materials comprising particles of metal compounds is a matrix, which can contain oxides of refractory metals or metalloids such as silicon. Reflective layers within the coating layers can comprise refractory metal silicides and related compounds characterized by the formulas TiSi. Ti.sub.3SiC.sub.2, TiAlSi, TiAN and similar compounds for Zr and Hf. The titania can be characterized by the formulas TiO.sub.2, Ti.sub.3O.sub.5. TiOx or TiO.sub.xN.sub.1-x with x 0 to 1. The silica can be at least one of SiO.sub.2, SiO.sub.2x or SiO.sub.2xN.sub.1-x with x=0 to 1.

  17. Chemical Processing of Nanostructured Coatings

    Science.gov (United States)

    2000-01-01

    in the literature ranging from IR imaging to anti-scratch to smart windows and waveguides. Uhlmann and Towee have taken a survey of the sol-gel...Proteins and enzymes can be encapsulated in silica glass (12), while still retaining their activity. Sol-gel coatings (13,14) of hydroxyapatite should also...Technology, 13, 261-65. 14. Lolpatin, C. M. Pizziloni, V., Alford, T. L., and Lawsaon, T (1998) Hydroxyapatite powders ad thin films prepared by sol

  18. Diamond coating in accelerator structure

    International Nuclear Information System (INIS)

    Lin, X.E.

    1998-08-01

    The future accelerators with 1 GeV/m gradient will give rise to hundreds of degrees instantaneous temperature rise on the copper surface. Due to its extraordinary thermal and electric properties, diamond coating on the surface is suggested to remedy this problem. Multi-layer structure, with the promise of even more temperature reduction, is also discussed, and a proof of principle experiment is being carried out

  19. Wear mechanisms of coated hardmetals

    International Nuclear Information System (INIS)

    Richter, V.

    2001-01-01

    In the paper several aspects of the wear mechanisms of coated hardmetals, ceramics and super-hard materials (CBN) in machining cast iron are discussed, with particular attention being given to high-speed machining of different cast iron grades. The influence of machining parameters, microstructure, composition and mechanical and chemical properties of the cutting tool and the work-piece material on wear are considered. (author)

  20. Coated Conductors under Tensile Stress

    International Nuclear Information System (INIS)

    Antonevici, Anca; Villaume, Alain; Villard, Catherine; Sulpice, Andre; Maron, Pierre Brosse; Bourgault, Daniel; Porcar, Laureline

    2006-01-01

    Critical current dependence versus strain is obtained for in-situ axial stress experiments on ISD YBCO and DyBCO coated conductors. The drop of critical current due to the apparition of first cracks in the superconducting ceramics is related to the passage in the plastic region of the substrate for a strain of about 0.3% and a stress higher then 500MPa. The superconductivity is preserved between the cracks

  1. Engineered Protein Coatings to Improve the Osseointegration of Dental and Orthopaedic Implants

    Science.gov (United States)

    Raphel, Jordan; Karlsson, Johan; Galli, Silvia; Wennerberg, Ann; Lindsay, Christopher; Haugh, Matthew; Pajarinen, Jukka; Goodman, Stuart B.; Jimbo, Ryo; Andersson, Martin; Heilshorn, Sarah C.

    2016-01-01

    Here we present the design of an engineered, elastin-like protein (ELP) that is chemically modified to enable stable coatings on the surfaces of titanium-based dental and orthopaedic implants by novel photocrosslinking and solution processing steps. The ELP includes an extended RGD sequence to confer bio-signaling and an elastin-like sequence for mechanical stability. ELP thin films were fabricated on cp-Ti and Ti6Al4V surfaces using scalable spin and dip coating processes with photoactive covalent crosslinking through a carbene insertion mechanism. The coatings withstood procedures mimicking dental screw and hip replacement stem implantations, a key metric for clinical translation. They promoted rapid adhesion of MG63 osteoblast-like cells, with over 80% adhesion after 24 hours, compared to 38% adhesion on uncoated Ti6Al4V. MG63 cells produced significantly more mineralization on ELP coatings compared to uncoated Ti6Al4V. Human bone marrow mesenchymal stem cells (hMSCs) had an earlier increase in alkaline phosphatase activity, indicating more rapid osteogenic differentiation and mineral deposition on adhesive ELP coatings. Rat tibia and femur in vivo studies demonstrated that cell-adhesive ELP-coated implants increased bone-implant contact area and interfacial strength after one week. These results suggest that ELP coatings withstand surgical implantation and promote rapid osseointegration, enabling earlier implant loading and potentially preventing micromotion that leads to aseptic loosening and premature implant failure. PMID:26790146

  2. A study of degradation resistance and cytocompatibility of super-hydrophobic coating on magnesium.

    Science.gov (United States)

    Zhang, Yufen; Feyerabend, Frank; Tang, Shawei; Hu, Jin; Lu, Xiaopeng; Blawert, Carsten; Lin, Tiegui

    2017-09-01

    Calcium stearate based super-hydrophobic coating was deposited on plasma electrolytic oxidation (PEO) pre-treated magnesium substrate. The pre-treated magnesium and super-hydrophobic coating covered sample were characterized by scanning electron microscopy, X-ray diffraction and electrochemical corrosion measurements. The cytocompatibility and degradation resistance of magnesium, pre-treated magnesium and super-hydrophobic coating were analysed in terms of cell adhesion and osteoblast differentiation. The results indicate that the calcium stearate top coating shows super-hydrophobicity and that the surface is composed of micro/nanostructure. The super-hydrophobic coating covered sample shows higher barrier properties compared with the PEO pre-treated magnesium and bare magnesium. Human osteoblast proliferation, but not differentiation is enhanced by the PEO coating. Contrary, the super-hydrophobic coating reduces proliferation, but enhances differentiation of osteoblast, observable by the formation of hydroxyapatite. The combination of corrosion protection and cell reaction indicates that this system could be interesting for biomedical applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Biological influence of Ca/P ratio on calcium phosphate coatings by sol-gel processing.

    Science.gov (United States)

    Catauro, M; Papale, F; Sapio, L; Naviglio, S

    2016-08-01

    The objective of this work has been to develop low temperature sol-gel glass coatings to modify the substrate surface and to evaluate their bioactivity and biocompatibility. Glasses, based on SiO2·CaO·P2O5, were synthesized by the sol-gel technique using tetraethyl orthosilicate, calcium nitrate tetrahydrate and triethyl phosphate as precursors of SiO2, CaO and P2O5, respectively. Those materials, still in the sol phase, have been used to coat substrates by means of the dip-coating technique. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) has been used for characterize coatings and a microstructural analysis has been obtained using scanning electron microscopy (SEM). The potential applications of the coatings in the biomedical field were evaluated by bioactivity and biocompatibility tests. The coated substrate was immersed in simulated body fluid (SBF) for 21days and the hydroxyapatite deposition on its surface was subsequently evaluated via SEM-EDXS analysis, as an index of bone-bonding capability. In order to study the cell behavior and response to our silica based materials, prepared via the sol-gel method, with various Ca/P ratio and coating substrate, we have used the human osteoblast-like U2OS cell line. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Effect of the deposition temperature on corrosion resistance and biocompatibility of the hydroxyapatite coatings

    Science.gov (United States)

    Vladescu, A.; Braic, M.; Azem, F. Ak; Titorencu, I.; Braic, V.; Pruna, V.; Kiss, A.; Parau, A. C.; Birlik, I.

    2015-11-01

    Hydroxyapatite (HAP) ceramics belong to a class of calcium phosphate-based materials, which have been widely used as coatings on titanium medical implants in order to improve bone fixation and thus to increase the lifetime of the implant. In this study, HAP coatings were deposited from pure HAP targets on Ti6Al4V substrates using the radio-frequency magnetron sputtering technique at substrate temperatures ranging from 400 to 800 °C. The surface morphology and the crystallographic structure of the films were investigated by atomic force microscopy (AFM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The corrosion resistance of the coatings in saliva solution at 37 °C was evaluated by potentiodynamic polarization. Additionally, the human osteosarcoma cell line (MG-63) was used to test the biocompatibility of the coatings. The results showed that all of the coatings grown uniformly and that the increasing substrate temperature induced an increase in their crystallinity. Corrosion performance of the coatings was improved with the increase of the substrate temperature from 400 °C to 800 °C. Furthermore, all the coatings support the attachment and growth of the osteosarcoma cells with regard to the in vitro test findings.

  5. Sol-Gel Derived Hydroxyapatite Coating on Mg-3Zn Alloy for Orthopedic Application

    Science.gov (United States)

    Singh, Sanjay; Manoj Kumar, R.; Kuntal, Kishor Kumar; Gupta, Pallavi; Das, Snehashish; Jayaganthan, R.; Roy, Partha; Lahiri, Debrupa

    2015-04-01

    In recent years, magnesium and its alloys have gained a lot of interest as orthopedic implant constituents because their biodegradability and mechanical properties are closer to that of human bone. However, one major concern with Mg in orthopedics is its high corrosion rate that results in the reduction of mechanical integrity before healing the bone tissue. The current study evaluates the sol-gel-derived hydroxyapatite (HA) coating on a selected Mg alloy (Mg-3Zn) for decreasing the corrosion rate and increasing the bioactivity of the Mg surface. The mechanical integrity of the coating is established as a function of the surface roughness of the substrate and the sintering temperature of the coating. Coating on a substrate roughness of 15-20 nm and sintering at 400°C shows the mechanical properties in similar range of bone, thus making it suitable to avoid the stress-shielding effect. The hydroxyapatite coating on the Mg alloy surface also increases corrosion resistance very significantly by 40 times. Bone cells are also found proliferating better in the HA-coated surface. All these benefits together establish the candidature of sol-gel HA-coated Mg-3Zn alloy in orthopedic application.

  6. Electron beam curing of coating

    International Nuclear Information System (INIS)

    Fujioka, S.; Fujikawa, Z.

    1974-01-01

    Electron beam curing (EBC) method, by which hardened coating film is obtained by polymerizing and cross-linking paint with electron beam, has finally reached industrialized stage. While about seven items such as short curing time, high efficiency of energy consumption, and homogeneous curing are enumerated as the advantages of EBC method, it has limitations of the isolation requirement from air needing the injection of inert gas, and considerable amount of initial investment. In the electron accelerators employed in EBC method, the accelerating voltage is 250 to 750 kV, and the tube current is several tens of mA to 200 mA. As an example of EBC applications, EBC ''Erio'' steel sheet was developed by the cooperative research of Nippon Steel Corp., Dai-Nippon Printing Co. and Toray Industries, Inc. It is a high-class pre-coated metal product made from galvanized steel sheets, and the flat sheets with cured coating are sold, and final products are fabricated by being worked in various shapes in users. It seems necessary to develop the paint which enables to raise added value by adopting the EBC method. (Wakatsuki, Y.)

  7. High Critical Current Coated Conductors

    Energy Technology Data Exchange (ETDEWEB)

    Paranthaman, M. P.; Selvamanickam, V. (SuperPower, Inc.)

    2011-12-27

    One of the important critical needs that came out of the DOE’s coated conductor workshop was to develop a high throughput and economic deposition process for YBCO. Metal-organic chemical vapor deposition (MOCVD) technique, the most critical steps in high technical micro fabrications, has been widely employed in semiconductor industry for various thin film growth. SuperPower has demonstrated that (Y,Gd)BCO films can be deposited rapid with world record performance. In addition to high critical current density with increased film thickness, flux pinning properties of REBCO films needs to be improved to meet the DOE requirements for various electric-power equipments. We have shown that doping with Zr can result in BZO nanocolumns, but at substantially reduced deposition rate. The primary purpose of this subtask is to develop high current density MOCVD-REBCO coated conductors based on the ion-beam assisted (IBAD)-MgO deposition process. Another purpose of this subtask is to investigate HTS conductor design optimization (maximize Je) with emphasis on stability and protection issues, and ac loss for REBCO coated conductors.

  8. ALARA trademark 1146 strippable coating

    International Nuclear Information System (INIS)

    Fricke, V.

    1999-01-01

    Strippable or temporary coatings are innovative technologies for decontamination that effectively reduce loose contamination at low cost. These coatings have become a viable option during the deactivation and decommissioning of both US Department of Energy (DOE) and commercial nuclear facilities to remove or fix loose contamination on both vertical and horizontal surfaces. The ALARA trademark 1146 strippable coating was demonstrated as part of the Savannah River Site LSDDP and successfully removed transferable (surface) contamination from multiple surfaces (metal and concrete) with an average decontamination factor for alpha contamination of 6.68 and an average percentage of alpha contamination removed of 85.0%. Beta contamination removed was an average DF of 5.55 and an average percentage removed of 82.0%. This paper is an Innovative Technology Summary Report designed to provide potential users with the information they need to quickly determine if a technology would apply to a particular environmental management problem. They also are designed for readers who may recommend that a technology be considered by prospective users. This Innovative Technology offers a 35% cost savings over the Baseline Technology

  9. Identificación morfológica de Ehrlichia sp. en las plaquetas de pacientes con infección por virus de la inmunodeficiencia humana, en Venezuela Morphologic identification of Ehrlichia sp. in the platelets of patients infected with the human immunodeficiency virus in Venezuela

    Directory of Open Access Journals (Sweden)

    Irene del Carmen de Tamí

    2004-11-01

    immunodeficiency syndrome (AIDS after a variable period during which the individual can develop different types of opportunistic infections whose severity depends on his/her immune status. Human ehrlichiosis is a newly-recognized tick-borne infectious disease caused by Ehrlichia spp., which are obligate intracellular, Gram-negative bacteria showing tropism for blood cells (leukocytes and platelets. In Venezuela, the disease was first recognized in humans in 1994, when intra-cytoplasmic microcolonies (morula were found in human platelets. METHODS: We collected peripheral blood samples from 87 HIV-positive persons that were received at the Immunology Laboratory of the Oncology and Hematology Institute in Caracas, Venezuela, one of the country's referral centers for cases of HIV infection. Slides prepared from buffy coat that had been stained with Wright's solution and sealed with resin for preservation were examined retrospectively under the light microscope. RESULTS: Ehrlichia spp. were found in the platelets of 12 of the 87 (13.8% patients whose slides were examined. CONCLUSION: The presence of Ehrlichia sp. in the platelets of HIV-positive patients suggests that ehrlichiosis should be among the differential diagnoses of opportunistic infection in this group of patients.

  10. Antimicrobial particulate silver coatings on stainless steel implants for fracture management

    Energy Technology Data Exchange (ETDEWEB)

    DeVasConCellos, Paul; Bose, Susmita [W.M. Keck Biomedical Materials Research Laboratory, School of Mechanical and Materials Engineering, Washington State University, Pullman, WA (United States); Beyenal, Haluk [School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA (United States); Bandyopadhyay, Amit, E-mail: amitband@wsu.edu [W.M. Keck Biomedical Materials Research Laboratory, School of Mechanical and Materials Engineering, Washington State University, Pullman, WA (United States); Zirkle, Lewis G. [Surgical Implant Generation Network (SIGN), Richland, WA (United States)

    2012-07-01

    We have used particulate silver coating on stainless steel to prevent in vivo bacterial infection. Stainless steel is commonly used as an implant material for fracture management. The antimicrobial use of silver has been well documented and studied, therefore the novelty of this research is the use of a particulate coating as well as facing the real world challenges of a fracture repair implant. The variable parameters for applying the coating were time of deposition, silver solution concentration, voltage applied, heat treatment temperature between 400 and 500 Degree-Sign C and time. The resultant coating is shown to be non-toxic to human osteoblasts using an MTT assay for proliferation and SEM images for morphology. In vitro silver release studies of various treatments were done using simulated body fluid. The bactericidal effects were tested by challenging the coatings with Pseudomonas aeruginosa in a bioreactor and compared against uncoated stainless steel. A 13-fold reduction in bacteria was observed at 24 h and proved to be statistically significant. - Highlights: Black-Right-Pointing-Pointer Processing of particulate silver coating that are strongly adherent on SS surface. Black-Right-Pointing-Pointer Optimized the amount of silver that is sufficient to reduce bacterial colonization but non-toxic to human bone tissue. Black-Right-Pointing-Pointer The adhesion strength of silver was sufficient to survive industrial sterilization steps used for fracture management devices.

  11. Synthesis of calcium hydrogen phosphate and hydroxyapatite coating on SS316 substrate through pulsed electrodeposition

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, Rajib, E-mail: rajibju4@gmail.com [Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India); Sengupta, Srijan [Department of Metallurgical and Materials Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India); Saha, Partha [Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India); Das, Karabi; Das, Siddhartha [Department of Metallurgical and Materials Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India)

    2016-12-01

    The orthopaedic implants for human body are generally made of different biomaterials like stainless steels or Ti based alloys. However, it has been found that from surface properties point of view, none of these materials is attractive for fast tissue or cell growth on the surface of implant. This is one of the most important criteria to assure quick bonding between implant and body tissues vis-à-vis minimum recovery time for the patient. Keeping in view of the above facts, this work involves the pulsed electro-deposition coating of biocompatible hydroxyapatite and its group compounds from a diluted bath of calcium and phosphate salt at various current densities over the biomaterial sheet of SS316. SEM study confirms different morphologies of the coatings at different current densities. Characterization techniques like X-ray diffraction, SEM with EDX and FTIR have been used to confirm the phase and percentage quantity of hydroxyapatite compound in the depositions. This coating can serve as a medium for faster tissue growth over the metallic implants. - Highlights: • Composite coatings of CaHPO{sub 4} and hydroxyapatite for biomedical application through pulsed electro-deposition. • Achieved optimum phase composition in view of crystallinity of both the phases. • Overall coating crystallinity of around 70% in view better bio compatibility. • In cyclic voltammetry it is observed that the deposition reaction is completely irreversible. • The deposited coating consists of nano-crystalline hydroxyapatite similar to human bone; which exhibits better bio-compatibility.

  12. Antimicrobial particulate silver coatings on stainless steel implants for fracture management

    International Nuclear Information System (INIS)

    DeVasConCellos, Paul; Bose, Susmita; Beyenal, Haluk; Bandyopadhyay, Amit; Zirkle, Lewis G.

    2012-01-01

    We have used particulate silver coating on stainless steel to prevent in vivo bacterial infection. Stainless steel is commonly used as an implant material for fracture management. The antimicrobial use of silver has been well documented and studied, therefore the novelty of this research is the use of a particulate coating as well as facing the real world challenges of a fracture repair implant. The variable parameters for applying the coating were time of deposition, silver solution concentration, voltage applied, heat treatment temperature between 400 and 500 °C and time. The resultant coating is shown to be non-toxic to human osteoblasts using an MTT assay for proliferation and SEM images for morphology. In vitro silver release studies of various treatments were done using simulated body fluid. The bactericidal effects were tested by challenging the coatings with Pseudomonas aeruginosa in a bioreactor and compared against uncoated stainless steel. A 13-fold reduction in bacteria was observed at 24 h and proved to be statistically significant. - Highlights: ► Processing of particulate silver coating that are strongly adherent on SS surface. ► Optimized the amount of silver that is sufficient to reduce bacterial colonization but non-toxic to human bone tissue. ► The adhesion strength of silver was sufficient to survive industrial sterilization steps used for fracture management devices.

  13. Oxidation study of Ta–Zr coatings

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yung-I, E-mail: yichen@mail.ntou.edu.tw; Chen, Sin-Min

    2013-02-01

    Refractory metal alloy coatings, such as Mo–Ru and Ta–Ru coatings, have been developed to protect glass molding dies. Forming intermetallic compounds in the coatings inhibits grain growth in high temperature environments when mass producing optical components. After annealing in oxygen containing atmospheres, a surface roughening of the Mo–Ru coatings and a soft oxide layer on the Ta–Ru coatings have been observed in our previous works. Oxidation resistance becomes critical in high-temperature applications. In this study, Ta–Zr coatings were deposited with a Ti interlayer on silicon wafers using direct current magnetron sputtering at 400 °C. The as-deposited Ta–Zr coatings possessed nanocrystallite or amorphous states, depending on the chemical compositions. The annealing treatments were conducted at 600 °C under atmospheres of 50 ppm O{sub 2}–N{sub 2} or 1% O{sub 2}–Ar, respectively. After the annealing treatment, this study investigated variations in crystalline structure, hardness, surface roughness, and chemical composition profiles. Preferential oxidation of Zr in the Ta–Zr coatings was verified using X-ray photoelectron spectroscopy, and the microstructure was observed using transmission electron microscopy. - Highlights: ►The as-deposited Ta-rich Ta–Zr coatings revealed an amorphous structure. ►The Zr-rich coatings presented a crystalline β-Zr phase and an amorphous matrix. ►Zr oxidized preferentially as Ta–Zr coatings annealed at 600 °C. ►The hardness of coatings revealed a parabolic relationship with the oxygen content. ►A protective oxide scale formed on the surface of the crystallized Zr-rich coatings.

  14. Ultra-thin Polyethylene glycol Coatings for Stem Cell Culture

    Science.gov (United States)

    Schmitt, Samantha K.

    Human mesenchymal stem cells (hMSCs) are a widely accessible and a clinically relevant cell type that are having a transformative impact on regenerative medicine. However, current clinical expansion methods can lead to selective changes in hMSC phenotype resulting from relatively undefined cell culture surfaces. Chemically defined synthetic surfaces can aid in understanding stem cell behavior. In particular we have developed chemically defined ultra-thin coatings that are stable over timeframes relevant to differentiation of hMSCs (several weeks). The approach employs synthesis of a copolymer with distinct chemistry in solution before application to a substrate. This provides wide compositional flexibility and allows for characterization of the orthogonal crosslinking and peptide binding groups. Characterization is done in solution by proton NMR and after crosslinking by X-ray photoelectron spectroscopy (XPS). The solubility of the copolymer in ethanol and low temperature crosslinking, expands its applicability to plastic substrates, in addition to silicon, glass, and gold. Cell adhesive peptides, namely Arg-Gly-Asp (RGD) fragments, are coupled to coating via different chemistries resulting in the urethane, amide or the thioester polymer-peptide bonds. Development of azlactone-based chemistry allowed for coupling in water at low peptide concentrations and resulted in either an amide or thioester bonds, depending on reactants. Characterization of the peptide functionalized coating by XPS, infrared spectroscopy and cell culture assays, showed that the amide linkages can present peptides for multiple weeks, while shorter-term presentation of a few days is possible using the more labile thioester bond. Regardless, coatings promoted initial adhesion and spreading of hMSCs in a peptide density dependent manner. These coatings address the following challenges in chemically defined cell culture simultaneously: (i) substrate adaptability, (ii) scalability over large areas

  15. Graphene-reinforced calcium silicate coatings for load-bearing implants.

    Science.gov (United States)

    Xie, Youtao; Li, Hongqing; Zhang, Chi; Gu, Xin; Zheng, Xuebin; Huang, Liping

    2014-04-01

    Owing to the superior mechanical properties and low coefficient of thermal expansion, graphene has been widely used in the reinforcement of ceramics. In the present study, various ratios of graphene (0.5 wt%, 1.5 wt% and 4 wt%) were reinforced into calcium silicate (CS) coatings for load-bearing implant surface modification. Surface characteristics of the graphene/calcium silicate (GC) composite coatings were characterized by scanning electron microscopy. Results show that the graphene plates (less than 4 wt% in the coatings) were embedded in the CS matrix homogeneously. The surfaces of the coatings showed a hierarchical hybrid nano-/microstructure, which is believed to be beneficial to the behaviors of the cell and early bone fixation of the implants. Wear resistance measured by a pin-on-disc model exhibited an obvious enhancement with the adoption of graphene plates. The weight losses of the GC coatings decreased with the increase of graphene content. However, too high graphene content (4 wt% or more) made the composite coatings porous and the wear resistance decreased dramatically. The weight loss was only 1.3 ± 0.2 mg for the GC coating containing 1.5 wt% graphene (denoted as GC1.5) with a load of 10 N and sliding distance of 500 m, while that of the pure CS coating reached up to 28.6 ± 0.5 mg. In vitro cytocompatibility of the GC1.5 coating was evaluated using a human marrow stem cell (hMSC) culture system. The proliferation and alkaline phosphatase, osteopontin and osteocalcin (OC) osteogenesis-related gene expression of the cells on the GC1.5 coating did not deteriorate with the adoption of graphene. Conversely, even better adhesion of the hMSCs was observed on the GC1.5 coating than on the pure CS coating. All of the results indicate that the GC1.5 coating is a good candidate for load-bearing implants.

  16. Stabilization and target delivery of Nattokinase using compression coating.

    Science.gov (United States)

    Law, D; Zhang, Z

    2007-05-01

    The aim of the work is to develop a new formulation in order to stabilize a nutraceutical enzyme Nattokinase (NKCP) in powders and to control its release rate when it passes through the gastrointestinal tract of human. NKCP powders were first compacted into a tablet, which was then coated with a mixture of an enteric material Eudragit L100-55 (EL100-55) and Hydroxypropylcellulose (HPC) by direct compression. The activity of the enzyme was determined using amidolytic assay and its release rates in artificial gastric juice and an intestinal fluid were quantified using bicinchoninic acid assay. Results have shown that the activity of NKCP was pressure independent and the coated tablets protected NKCP from being denatured in the gastric juice, and realized its controlled release to the intestine based on in vitro experiments.

  17. Electron beam treatments of electrophoretic ceramic coatings

    International Nuclear Information System (INIS)

    De Riccardis, M.F.; Carbone, D.; Piscopiello, E.; Antisari, M. Vittori

    2008-01-01

    In this work a method to densify ceramic coating obtained by electrophoresis and to improve its adhesion to the substrate is proposed. It consists in irradiating the coating surface by electron beam (EB). Alumina and alumina-zirconia coatings were deposited on stainless steel substrates and treated by low power EB. SEM, XRD and TEM characterizations demonstrated that the sintering occurred. Moreover, it is shown that on alumina-zirconia coating the EB irradiation produced a composite material consisting principally of tetragonal zirconia particles immersed in an amorphous alumina matrix. The adhesion stress of EB treated coating was estimated by stud pull test and it was found to be comparable to that of plasma-sprayed coatings

  18. Laser cladding of bioactive glass coatings.

    Science.gov (United States)

    Comesaña, R; Quintero, F; Lusquiños, F; Pascual, M J; Boutinguiza, M; Durán, A; Pou, J

    2010-03-01

    Laser cladding by powder injection has been used to produce bioactive glass coatings on titanium alloy (Ti6Al4V) substrates. Bioactive glass compositions alternative to 45S5 Bioglass were demonstrated to exhibit a gradual wetting angle-temperature evolution and therefore a more homogeneous deposition of the coating over the substrate was achieved. Among the different compositions studied, the S520 bioactive glass showed smoother wetting angle-temperature behavior and was successfully used as precursor material to produce bioactive coatings. Coatings processed using a Nd:YAG laser presented calcium silicate crystallization at the surface, with a uniform composition along the coating cross-section, and no significant dilution of the titanium alloy was observed. These coatings maintain similar bioactivity to that of the precursor material as demonstrated by immersion in simulated body fluid. Copyright 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  19. Crystallization of DNA-coated colloids

    Science.gov (United States)

    Wang, Yu; Wang, Yufeng; Zheng, Xiaolong; Ducrot, Étienne; Yodh, Jeremy S.; Weck, Marcus; Pine, David J.

    2015-01-01

    DNA-coated colloids hold great promise for self-assembly of programmed heterogeneous microstructures, provided they not only bind when cooled below their melting temperature, but also rearrange so that aggregated particles can anneal into the structure that minimizes the free energy. Unfortunately, DNA-coated colloids generally collide and stick forming kinetically arrested random aggregates when the thickness of the DNA coating is much smaller than the particles. Here we report DNA-coated colloids that can rearrange and anneal, thus enabling the growth of large colloidal crystals from a wide range of micrometre-sized DNA-coated colloids for the first time. The kinetics of aggregation, crystallization and defect formation are followed in real time. The crystallization rate exhibits the familiar maximum for intermediate temperature quenches observed in metallic alloys, but over a temperature range smaller by two orders of magnitude, owing to the highly temperature-sensitive diffusion between aggregated DNA-coated colloids. PMID:26078020

  20. Thin low Z coatings for plasma devices

    International Nuclear Information System (INIS)

    Norem, J.; Bowers, D.A.

    1978-05-01

    Coating the walls of the vacuum chamber with beryllium or some other low Z material has been proposed as a possible means of solving the problems of high Z influx into plasmas. We attempt to demonstrate that very thin, low Z coatings are compatible with the operation of plasma devices and beneficial to plasma performance. We determine that the thickness of coating material required is only about 10 monolayers. In a radiation environment, radiation-induced solute segregation should help to maintain the integrity of such thin coatings against diffusion and other processes. We discuss the properties of these thin coatings and possible means of in situ application and maintenance. Since deposition of plasma impurities on the walls will occur anyway, we discuss injection of solid pellets into the plasma as a direct way of introducing impurities which would ultimately serve as coating material

  1. Tungsten thick coatings for plasma facing components

    International Nuclear Information System (INIS)

    Riccardi, B.; Pizzuto, A.; Orsini, A.; Libera, S.; Visca, E.; Bertamini, L.; Casadei, F.; Severini, E.; Montanari, R.; Litunovsky, N.

    1998-01-01

    The aim of the R and D activity was to realize thick W coatings on CuCrZr hollow bars and to test the mock ups with respect to thermal fatigue. Eight mock ups provided of 4 mm thick W coating were finally manufactured. The bonding integrity between coating and substrate was checked by means of an Ultrasonic apparatus. Characterisation of coatings was performed in order to assess microstructure, impurity content, density, tensile strength, adhesion strength, thermal conductivity and thermal expansion coefficient. Macroscopic residual strain measurements were performed by means of 'hole drilling' technique. The activities performed demonstrated the feasibility of thick Tungsten coatings on geometries with more complex residual strain distribution. These coatings are reliable armour of medium heat flux plasma facing component. (author)

  2. Simulation to coating weight control for galvanizing

    Science.gov (United States)

    Wang, Junsheng; Yan, Zhang; Wu, Kunkui; Song, Lei

    2013-05-01

    Zinc coating weight control is one of the most critical issues for continuous galvanizing line. The process has the characteristic of variable-time large time delay, nonlinear, multivariable. It can result in seriously coating weight error and non-uniform coating. We develop a control system, which can automatically control the air knives pressure and its position to give a constant and uniform zinc coating, in accordance with customer-order specification through an auto-adaptive empirical model-based feed forward adaptive controller, and two model-free adaptive feedback controllers . The proposed models with controller were applied to continuous galvanizing line (CGL) at Angang Steel Works. By the production results, the precise and stability of the control model reduces over-coating weight and improves coating uniform. The product for this hot dip galvanizing line does not only satisfy the customers' quality requirement but also save the zinc consumption.

  3. Cermet coatings for solar Stirling space power

    International Nuclear Information System (INIS)

    Jaworske, Donald A.; Raack, Taylor

    2004-01-01

    Cermet coatings, molecular mixtures of metal and ceramic, are being considered for the heat inlet surface of a solar Stirling space power convertor. The role of the cermet coating is to absorb as much of the incident solar energy as possible. The ability to mix metal and ceramic at the atomic level offers the opportunity to tailor the composition and the solar absorptance of these coatings. Several candidate cermet coatings were created and their solar absorptance was characterized as-manufactured and after exposure to elevated temperatures. Coating composition was purposely varied through the thickness of the coating. As a consequence of changing composition, islands of metal are thought to form in the ceramic matrix. Computer modeling indicated that diffusion of the metal atoms played an important role in island formation while the ceramic was important in locking the islands in place. Much of the solar spectrum is absorbed as it passes through this labyrinth

  4. Microneedle Coating Techniques for Transdermal Drug Delivery

    Directory of Open Access Journals (Sweden)

    Rita Haj-Ahmad

    2015-11-01

    Full Text Available Drug administration via the transdermal route is an evolving field that provides an alternative to oral and parenteral routes of therapy. Several microneedle (MN based approaches have been developed. Among these, coated MNs (typically where drug is deposited on MN tips are a minimally invasive method to deliver drugs and vaccines through the skin. In this review, we describe several processes to coat MNs. These include dip coating, gas jet drying, spray coating, electrohydrodynamic atomisation (EHDA based processes and piezoelectric inkjet printing. Examples of process mechanisms, conditions and tested formulations are provided. As these processes are independent techniques, modifications to facilitate MN coatings are elucidated. In summary, the outcomes and potential value for each technique provides opportunities to overcome formulation or dosage form limitations. While there are significant developments in solid degradable MNs, coated MNs (through the various techniques described have potential to be utilized in personalized drug delivery via controlled deposition onto MN templates.

  5. Tantalum-based multilayer coating on cobalt alloys in total hip and knee replacement

    Energy Technology Data Exchange (ETDEWEB)

    Balagna, C., E-mail: cristina.balagna@polito.it [Institute of Materials Engineering and Physics, Applied Science and Technology Department, Politecnico di Torino, Corso Duca degli Abruzzi 24,10129 Torino (Italy); Faga, M.G. [Istituto di Scienza e Tecnologia dei Materiali Ceramici, Consiglio Nazionale delle Ricerche, Strada delle Cacce 73, 10135 Torino (Italy); Spriano, S. [Institute of Materials Engineering and Physics, Applied Science and Technology Department, Politecnico di Torino, Corso Duca degli Abruzzi 24,10129 Torino (Italy)

    2012-05-01

    Cobalt-chromium-molybdenum (CoCrMo) alloys are widely used in total hip and knee joint replacement, due to high mechanical properties and resistance to wear and corrosion. They are able to form efficient artificial joints by means of coupling metal-on-polymer or metal-on-metal contacts. However, a high concentration of stress and direct friction between surfaces leads to the formation of polyethylene wear debris and the release of toxic metal ions into the human body, limiting, as a consequence, the lifetime of implants. The aim of this research is a surface modification of CoCrMo alloys in order to improve their biocompatibility and to decrease the release of metal ions and polyethylene debris. Thermal treatment in molten salts was the process employed for the deposition of tantalum-enriched coating. Tantalum and its compounds are considered biocompatible materials with low ion release and high corrosion resistance. Three different CoCrMo alloys were processed as substrates. An adherent coating of about 1 {mu}m of thickness, with a multilayer structure consisting of two tantalum carbides and metallic tantalum was deposited. The substrates and modified layers were characterized by means of structural, chemical and morphological analysis. Moreover nanoindentation, scratch and tribological tests were carried out in order to evaluate the mechanical behavior of the substrates and coating. The hardness of the coated samples increases more than double than the untreated alloys meanwhile the presence of the coating reduced the wear volume and rate of about one order of magnitude. - Highlights: Black-Right-Pointing-Pointer Thermal treatment in molten salts deposits a Ta-based coating on Co-based alloys. Black-Right-Pointing-Pointer Coating is composed by one or two tantalum carbides and/or metallic tantalum. Black-Right-Pointing-Pointer The coating structure depends on thermal temperature and substrates carbon content. Black-Right-Pointing-Pointer Coating is able to

  6. Bisphosphonate-coated BSA nanoparticles lack bone targeting after systemic administration.

    Science.gov (United States)

    Wang, Guilin; Kucharski, Cezary; Lin, Xiaoyue; Uludağ, Hasan

    2010-09-01

    A polymeric conjugate of polyethyleneimine-graft-poly(ethylene glycol) and 2-(3-mercaptopropylsulfanyl)-ethyl-1,1-bisphosphonic acid (PEI-PEG-thiolBP) was prepared and used for surface coating of bovine serum albumin (BSA) nanoparticles (NPs) designed for bone-specific delivery of bone morphogenetic protein-2 (BMP-2). The NP coating was achieved with a dialysis and an evaporation method, and the obtained NPs were characterized by particle size, zeta-potential, morphology, and cytotoxicity in vitro. The particle size and surface charge of the NPs could be effectively tuned by the PEG and thiolBP substitution ratios of the conjugate, the coating method, and the polymer concentration used for coating. The PEG modification on PEI reduced the toxicity of PEI and the coated NPs, based on in vitro assessment with human C2C12 cells and rat bone marrow stromal cells. On the basis of an alkaline phosphatase (ALP) induction assay, the NP-encapsulated BMP-2 displayed full retention of its bioactivity, except for BMP-2 in PEI-coated NPs. By encapsulating (125)I-labeled BMP-2, the polymer-coated NPs were assessed for hydroxyapatite (HA) affinity; all NP-encapsulated BMP-2 showed significant affinity to HA as compared with free BMP-2 in vitro, and the PEI-PEG-thiolBP coated NPs improved the in vivo retention of BMP-2 compared with uncoated NPs. However, the biodistribution of NPs after intravenous injection in a rat model indicated no beneficial effects of thiolBP-coated NPs for bone targeting. Our results suggested that the BP-conjugated NPs are useful for localized delivery of BMP-2 in bone repair and regeneration, but they are not effective for bone targeting after intravenous administration.

  7. Effects of mesenchymal stem cell and fibroblast coating on immunogenic potential of prosthetic meshes in vitro.

    Science.gov (United States)

    Gao, Yue; Krpata, David M; Criss, Cory N; Liu, Lijia; Posielski, Natasza; Rosen, Michael J; Novitsky, Yuri W

    2014-08-01

    The aim of this study was to reveal the effect of fibroblast or mesenchymal stem cell (MSC) coating on the mesh-induced production of IL-1β, IL-6, and VEGF by macrophages. Four commonly used surgical meshes were tested in this study, including Parietex, SoftMesh, TIGR, and Strattice. One-square-centimeter pieces of each mesh were placed on top of a monolayer of human fibroblasts or rat MSCs. The coating status was monitored with a light microscope. The human promonocytic cell line U937 was induced to differentiate into macrophages (MΦ). Three weeks later, meshes were transferred to new 24-well plates and cocultured with the MΦs for 72 h. Culture medium was collected and analyzed for IL-1β, IL-6, and VEGF production using standard ELISA essays. Parallel mesh samples were fixed with paraformaldehyde or glutaraldehyde for histology or transmission electronic microscopy (TEM) analyses, respectively. Uncoated meshes induced increased production of all three cytokines compared with macrophages cultured alone. HF coating further increased the production of both IL-6 and VEGF but reduced IL-1β production. Except for the SoftMesh group, MSC coating significantly blunted release of all cytokines to levels even lower than with MΦs cultured alone. MΦs tended to deteriorate in the presence of MSCs. Both histology and TEM revealed intimate interactions between cell-coated meshes and MΦs. Cytokine response to fibroblast coating varied, while MSC coating blunted the immunogenic effect of both synthetic and biologic meshes in vitro. Cell coating appears to affect mesh biocompatibility and may become a key process in mesh evolution.

  8. Stabilizing lead bullets in shooting range soil by phosphate-based surface coating

    Directory of Open Access Journals (Sweden)

    Bin Hua

    2016-08-01

    Full Text Available Soil lead (Pb is well known as a threat to human health and ecosystem. Although relatively insoluble, lead bullets in shooting range soil can be readily released into soluble forms through natural weathering processes and thus pose significant human and environmental risks. In this study, laboratory experiments were conducted to investigate if the Pb bullets in shooting range soil can be stabilized through surface coating of phosphate-based materials. Results indicated that FePO4 or AlPO4 coatings, insoluble metal phosphates, have been successfully formed on the surface of the Pb bullets. The EPA Toxicity Characteristic Leaching Procedure (TCLP test showed that FePO4 or AlPO4 surface coating would effectively reduce the Pb solubility or leachability of the bullets. The surface coating under pH of <5.5 for 7 days could achieve 92–100% reduction, with 85–98% by FePO4 coating and 77–98% by AlPO4 coating as compared with the non-coating. Leachable Pb concentration in the contaminated shooting range soil was reduced by 85–98% or 77–98% as a result of the FePO4 or AlPO4 solution treatment. This study demonstrated that the FePO4 or AlPO4–based surface coating on lead bullets can effectively inhibit the Pb weathering and significantly reduce the Pb release from soil through in situ chemical stabilization, which could be potentially applicable as a cost-effective and environmental-sound technology for the remediation of Pb-contaminated shooting range soil.

  9. Chitosan-based coatings in the prevention of intravascular catheter-associated infections.

    Science.gov (United States)

    Mendoza, Gracia; Regiel-Futyra, Anna; Tamayo, Alejandra; Monzon, Marta; Irusta, Silvia; de Gregorio, Miguel Angel; Kyzioł, Agnieszka; Arruebo, Manuel

    2018-01-01

    Central venous access devices play an important role in patients with prolonged intravenous administration requirements. In the last years, the coating of these devices with bactericidal compounds has emerged as a potential tool to prevent bacterial colonization. Our study describes the modification of 3D-printed reservoirs and silicone-based catheters, mimicking central venous access devices, through different approaches including their coating with the well known biocompatible and bactericidal polymer chitosan, with the anionic polysaccharide alginate; also, plasma treated surfaces were included in the study to promote polymer adhesion. The evaluation of the antimicrobial action of those surface modifications compared to that exerted by a model antibiotic (ciprofloxacin) adsorbed on the surface of the devices was carried out. Surface characterization was developed by different methodologies and the bactericidal effects of the different coatings were assayed in an in vitro model of Staphylococcus aureus infection. Our results showed a significant reduction in the reservoir roughness (≤73%) after coating though no changes were observed for coated catheters which was also confirmed by scanning electron microscopy, pointing to the importance of the surface device topography for the successful attachment of the coating and for the subsequent development of bactericidal effects. Furthermore, the single presence of chitosan on the reservoirs was enough to fully inhibit bacterial growth exerting the same efficiency as that showed by the model antibiotic. Importantly, chitosan coating showed low cytotoxicity against human keratinocytes, human lung adenocarcinoma epithelial cells, and murine colon carcinoma cells displaying viability percentages in the range of the control samples (>95%). Chitosan-based coatings are proposed as an effective and promising solution in the prevention of microbial infections associated to medical devices.

  10. The application of epoxy resin coating in grounding grid

    Science.gov (United States)

    Hu, Q.; Chen, Z. R.; Xi, L. J.; Wang, X. Y.; Wang, H. F.

    2018-01-01

    Epoxy resin anticorrosion coating is widely used in grounding grid corrosion protection because of its wide range of materials, good antiseptic effect and convenient processing. Based on the latest research progress, four kinds of epoxy anticorrosive coatings are introduced, which are structural modified epoxy coating, inorganic modified epoxy coating, organic modified epoxy coating and polyaniline / epoxy resin composite coating. In this paper, the current research progress of epoxy base coating is analyzed, and prospected the possible development direction of the anti-corrosion coating in the grounding grid, which provides a reference for coating corrosion prevention of grounding materials.

  11. ETV Program Report: Coatings for Wastewater Collection Systems - Standard Cement Materials, Epoxy Coating 4553

    Science.gov (United States)

    The Standard Cement Materials, Inc. Standard Epoxy Coating 4553™ (SEC 4553) epoxy coating used for wastewater collection system rehabilitation was evaluated by EPA’s Environmental Technology Verification Program under laboratory conditions at the Center for Innovative Grouting Ma...

  12. Cermet Coatings for Solar Stirling Space Power

    Science.gov (United States)

    Jaworske, Donald A.; Raack, Taylor

    2004-01-01

    Cermet coatings, molecular mixtures of metal and ceramic are being considered for the heat inlet surface of a solar Stirling space power converter. This paper will discuss the solar absorption characteristics of as-deposited cermet coatings as well as the solar absorption characteristics of the coatings after heating. The role of diffusion and island formation, during the deposition process and during heating will also be discussed.

  13. Biomarkers in white-coat hypertension

    OpenAIRE

    Martin, Catherine Ann

    2017-01-01

    The introduction of ambulatory blood pressure monitoring in the 1960s provided new insights into the nature of high blood pressure disorders. Blood pressure is now categorised into four quadrants:normotension, masked hypertension, hypertension and white-coat hypertension. In white-coat hypertension blood pressure is elevated when taken at the doctor’s office but normal if taken outside the doctor’s office. Several controversies are associated with white-coat hypertension, which are discuss...

  14. Method to produce catalytically active nanocomposite coatings

    Science.gov (United States)

    Erdemir, Ali; Eryilmaz, Osman Levent; Urgen, Mustafa; Kazmanli, Kursat

    2016-02-09

    A nanocomposite coating and method of making and using the coating. The nanocomposite coating is disposed on a base material, such as a metal or ceramic; and the nanocomposite consists essentially of a matrix of an alloy selected from the group of Cu, Ni, Pd, Pt and Re which are catalytically active for cracking of carbon bonds in oils and greases and a grain structure selected from the group of borides, carbides and nitrides.

  15. Study of chromate coatings by radioisotope tracing

    International Nuclear Information System (INIS)

    Drozda, T.; Maleczki, E.; Farkas, G.

    1984-01-01

    New radioactive tracer methods were developed to determine chromium(III) and total chromium [chromium(III)+chromium(VI)] content simultaneously. They are capable of investigating solutions and the conversion coating itself in the solid phase, respectively. The increase of chromium(III) concentration in the yellow chromate coating, and the chromium(III) to total chromium ratio in the conversion coating were determined as a function of the treating period. (author)

  16. New PVD Technologies for New Ordnance Coatings

    Science.gov (United States)

    2012-04-01

    characteristics using a Tantalum and a Chrome target; 4) Deposition of Ta coatings and reactive deposition of CrN; 5) Deposition parameters affecting film...Vapor Deposition (PVD); High Power Impulse Magnetron Sputtering (HIPIMS); Modulated Pulsed Power (MPP); Tantalum; Chrome ; Ta coatings; CrN; coating...The pre-production chemicals and acids are hazardous and hexavalent Cr is a known carcinogen. Significant annual expenditures are necessary to

  17. Testing of coatings for the nuclear industry

    International Nuclear Information System (INIS)

    Goldberg, G.

    1977-01-01

    Commercial scale nuclear power generating plant coatings must be able to withstand simultaneous exposure both to high humidity, and to cumulative radiation dosage, at elevated temperatures, for the design life of the plant. The coatings must be decontaminable by means other than by stripping, that is, actual physical removal, and must be of sufficient durability to withstand projected conditions of a loss of coolant accident. Tests to show that coatings are expected to do more than retard corrosion and erosion are described

  18. Heat-resistant hydrophobic-oleophobic coatings

    OpenAIRE

    Uyanik, Mehmet; Arpac, Ertugrul; Schmidt, Helmut K.; Akarsu, Murat; Sayilkan, Funda; Sayilkan, Hikmet

    2006-01-01

    Thermally and chemically durable hydrophobic oleophobic coatings, containing different ceramic particles such as SiO2, SiC, Al 2O3, which can be alternative instead of Teflon, have been developed and applied on the aluminum substrates by spin-coating method. Polyimides, which are high-thermal resistant heteroaromatic polymers, were synthesized, and fluor oligomers were added to these polymers to obtain hydrophobic-oleophobic properties. After coating, Al surface was subjected to Taber-abrasio...

  19. Surface coatings deposited by CVD and PVD

    International Nuclear Information System (INIS)

    Gabriel, H.M.

    1982-01-01

    The demand for wear and corrosion protective coatings is increasing due to economic facts. Deposition processes in gas atmospheres like the CVD and PVD processes attained a tremendous importance especially in the field of the deposition of thin hard refractory and ceramic coatings. CVD and PVD processes are reviewed in detail. Some examples of coating installations are shown and numerous applications are given to demonstrate the present state of the art. (orig.) [de

  20. Method to produce catalytically active nanocomposite coatings

    Energy Technology Data Exchange (ETDEWEB)

    Erdemir, Ali; Eryilmaz, Osman Levent; Urgen, Mustafa; Kazmanli, Kursat

    2017-12-19

    A nanocomposite coating and method of making and using the coating. The nanocomposite coating is disposed on a base material, such as a metal or ceramic; and the nanocomposite consists essentially of a matrix of an alloy selected from the group of Cu, Ni, Pd, Pt and Re which are catalytically active for cracking of carbon bonds in oils and greases and a grain structure selected from the group of borides, carbides and nitrides.