WorldWideScience

Sample records for adhesion molecule-modified biomaterials

  1. Staphylococcus epidermidis adhesion on hydrophobic and hydrophilic textured biomaterial surfaces

    It is of great interest to use nano- or micro-structured surfaces to inhibit microbial adhesion and biofilm formation and thereby to prevent biomaterial-associated infection, without modification of the surface chemistry or bulk properties of the materials and without use of the drugs. Our previous study showed that a submicron textured polyurethane surface can inhibit staphylococcal bacterial adhesion and biofilm formation. To further understand the effect of the geometry of textures on bacterial adhesion as well as the underlying mechanism, in this study, submicron and micron textured polyurethane surfaces featuring ordered arrays of pillars were fabricated and modified to have different wettabilities. All the textured surfaces were originally hydrophobic and showed significant reductions in Staphylococcus epidermidis RP62A adhesion in phosphate buffered saline or 25% platelet poor plasma solutions under shear, as compared to smooth surfaces. After being subjected to an air glow discharge plasma treatment, all polyurethane surfaces were modified to hydrophilic, and reductions in bacterial adhesion on surfaces were subsequently found to be dependent on the size of the patterns. The submicron patterned surfaces reduced bacterial adhesion, while the micron patterned surfaces led to increased bacterial adhesion. The extracellular polymeric substances (EPS) from the S. epidermidis cell surfaces were extracted and purified, and were coated on a glass colloidal surface so that the adhesion force and separation energy in interactions of the EPS and the surface could be measured by colloidal probe atomic force microscopy. These results were consistent with the bacterial adhesion observations. Overall, the data suggest that the increased surface hydrophobicity and the decreased availability of the contact area contributes to a reduction in bacterial adhesion to the hydrophobic textured surfaces, while the availability of the contact area is the primary determinant factor

  2. Oral bacterial adhesion forces to biomaterial surfaces constituting the bracket-adhesive-enamel junction in orthodontic treatment

    Mei, Li; Busscher, Henk J; van der Mei, Henny C; Chen, Yangxi; de Vries, Joop; Ren, Yijin

    2009-01-01

    Bacterial adhesion to biomaterial surfaces constituting the bracket-adhesive-enamel junction represents a growing problem in orthodontics, because bacteria can adversely affect treatment by causing demineralization of the enamel surface around the brackets. It is important to know the forces with wh

  3. Biomaterials

    Van Mourik, P.; Van Dam, J.; Picken, S.J.; Ursem, B.

    2013-01-01

    The metabolic pathways of living organisms produce biomaterials. Hence, in principle biomaterials are fully sustainable. This does not mean that their processing and application have no impact on the environment, e.g. the recycling of natural rubber remains a problem. Biomaterials are applied in a w

  4. Biomaterials

    Van Mourik, P; van Dam, J; Picken, S.J.; Ursem, B.

    2013-01-01

    The metabolic pathways of living organisms produce biomaterials. Hence, in principle biomaterials are fully sustainable. This does not mean that their processing and application have no impact on the environment, e.g. the recycling of natural rubber remains a problem. Biomaterials are applied in a wide range of consumer products, varying from clothing via temporary packaging materials to car parts. Examples are the paper we print on, the wooden table we sit around and the jeans we wear. This ...

  5. Biomaterials

    Migonney , Véronique

    2014-01-01

    Discovered in the 20th century, biomaterials have contributed to many of the incredible scientific and technological advancements made in recent decades. This book introduces and details the tenets of biomaterials, their relevance in a various fields, practical applications of their products, and potential advancements of the years to come. A comprehensive resource, the text covers the reasons that certain properties of biomaterials contribute to specific applications, and students and researchers will appreciate this exhaustive textbook.

  6. Extracellular matrix-mimetic adhesive biomaterials for bone repair

    Shekaran, Asha; Andrés J. García

    2010-01-01

    Limited osseointegration of current orthopaedic biomaterials contributes to the failure of implants such as arthroplasties, bone screws and bone grafts, which present a large socioeconomic cost within the United States. These implant failures underscore the need for biomimetic approaches that modulate host cell-implant material responses to enhance implant osseointegration and bone formation. Bioinspired strategies have included functionalizing implants with ECM proteins or ECM-derived peptid...

  7. Biomaterial based novel polyurethane adhesives for wood to wood and metal to metal bonding

    Mitesh Ramanlal Patel

    2009-01-01

    Full Text Available Polyurethane adhesives made from synthetic chemicals are non-biodegradable, costly and difficult to find raw materials from local market. To avoid solid pollution problem, cost effectiveness and easy availability of raw materials, biomaterials based polyurethane adhesives are used in current industrial interest. Direct use of castor oil in polyurethane adhesive gives limited hardness. Modification on active sites of castor oil to utilize double bond of unsaturated fatty acid and carboxyl group yields new modified or activated polyols, which can be utilized for polyurethane adhesive formulation. In view of this, we have synthesized polyurethane adhesives from polyester polyols, castor oil based polyols and epoxy based polyols with Isocyanate adducts based on castor oil and trimethylolpropane. To study the effects of polyurethane adhesive strength (i.e. lap shear strength on wood-to-wood and metal-to-metal bonding through various types of polyols, cross-linking density, isocyanate adducts and also to compare adhesive strength between wood to wood and metal to metal surface. These polyols and polyurethanes were characterized through GPC, NMR and IR-spectroscopy, gel and surface drying time. Thermal stability of PU adhesives was determined under the effect of cross-linking density (NCO/OH ratio. The NCO/OH ratio (1.5 was optimized for adhesives as the higher NCO/OH ratio (2.0 increasing cross-linking density and decreases adhesion. Lower NCO/OH ratio (1.0 provideslow cross-linking density and low strength of adhesives.

  8. Concise review of mechanisms of bacterial adhesion to biomaterials and of techniques used in estimating bacteria-material interactions

    Katsikogianni M.

    2004-12-01

    Full Text Available This article reviews the mechanisms of bacterial adhesion to biomaterial surfaces, the factors affecting the adhesion, the techniques used in estimating bacteria-material interactions and the models that have been developed in order to predict adhesion. The process of bacterial adhesion includes an initial physicochemical interaction phase and a late molecular and cellular one. It is a complicated process influenced by many factors, including the bacterial properties, the material surface characteristics, the environmental factors, such as the presence of serum proteins and the associated flow conditions. Two categories of techniques used in estimating bacteria-material interactions are described: those that utilize fluid flowing against the adhered bacteria and counting the percentage of bacteria that detach, and those that manipulate single bacteria in various configurations which lend themselves to more specific force application and provide the basis for theoretical analysis of the receptor-ligand interactions. The theories that are reviewed are the Derjaguin-Landau-Verwey-Overbeek (DLVO theory, the thermodynamic approach and the extended DLVO theory. Over the years, significant work has been done to investigate the process of bacterial adhesion to biomaterial surfaces, however a lot of questions still remain unanswered.

  9. Insight on stem cell preconditioning and instructive biomaterials to enhance cell adhesion, retention, and engraftment for tissue repair.

    Shafiq, Muhammad; Jung, Youngmee; Kim, Soo Hyun

    2016-06-01

    Stem cells are a promising solution for the treatment of a variety of diseases. However, the limited survival and engraftment of transplanted cells due to a hostile ischemic environment is a bottleneck for effective utilization and commercialization. Within this environment, the majority of transplanted cells undergo apoptosis prior to participating in lineage differentiation and cellular integration. Therefore, in order to maximize the clinical utility of stem/progenitor cells, strategies must be employed to increase their adhesion, retention, and engraftment in vivo. Here, we reviewed key strategies that are being adopted to enhance the survival, retention, and engraftment of transplanted stem cells through the manipulation of both the stem cells and the surrounding environment. We describe how preconditioning of cells or cell manipulations strategies can enhance stem cell survival and engraftment after transplantation. We also discuss how biomaterials can enhance the function of stem cells for effective tissue regeneration. Biomaterials can incorporate or mimic extracellular function (ECM) function and enhance survival or differentiation of transplanted cells in vivo. Biomaterials can also promote angiogenesis, enhance engraftment and differentiation, and accelerate electromechanical integration of transplanted stem cells. Insight gained from this review may direct the development of future investigations and clinical trials. PMID:27016619

  10. UV- Killed Staphylococcus aureus Enhances Adhesion and Differentiation of Osteoblasts on Bone-associated Biomaterials

    Somayaji, Shankari N.; Huet, Yvette M.; Gruber, Helen E.; Hudson, Michael C

    2010-01-01

    Titanium alloys (Ti) are the preferred material for orthopaedic applications. However, very often, these metallic implants loosen over a long period and mandate revision surgery. For implant success, osteoblasts must adhere to the implant surface and deposit a mineralized extracellular matrix. Here, we utilized UV-killed Staphylococcus aureus as a novel osteoconductive coating for Ti surfaces. S. aureus expresses surface adhesins capable of binding to bone and biomaterials directly. Furthermo...

  11. Adhesion of resin composites to biomaterials in dentistry: an evaluation of surface conditioning methods

    Özcan, Mutlu

    2003-01-01

    Since previous investigations revealed that most clinical failures in adhesively luted ceramic restorations initiate from the cementation or internal surfaces, the study presented in Chapter II evaluated the effect of three different surface conditioning methods on the bond strength of a Bis-GMA based luting cement to glass ceramics, glass infiltrated alumina, glass infiltrated ZrO2 reinforced alumina. The three conditioning methods assesed were: (1) HF acid etching, (2) Air-borne particle ab...

  12. Adhesión bacteriana a biomateriales Bacterial adhesion to biomaterials

    C Ábalos

    2005-02-01

    Full Text Available En términos generales, para la adhesión bacteriana, influyen cuatro elementos: Material, Microorganismos, antimicrobianos y mecanismos de defensa. La influencia del material es más importante en los estadios iniciales de la adhesión, pudiendo influir el mismo material, su rugosidad o su energía superficial., si es que existe una influencia del material en la adhesión bacteriana, esta reside en las caracteristicas de la película adquirida y en la especificidad de las proteinas adsorbidas salivares (receptores, que puedan ser condicionadas por la composición del material o por las características de superficie de este.In general terms, there are four elements which influence on bacterial adhesion: the material, the micro organisms, antimicrobials and defence mechanisms. The influence of the material is more relevant at the initial states of adhesion where the proper material, its roughness or its superficial energy can have some influence. If there is some influence of the material in the bacterial adhesion, it relies on the features of the acquired film and on the specificity of the adsorved salivary proteins (receptors, which can be influenced by the composition of the material or the characteristics of its surface.

  13. Zirconia as a Dental Biomaterial

    Alvaro Della Bona; Pecho, Oscar E.; Rodrigo Alessandretti

    2015-01-01

    Ceramics are very important in the science of dental biomaterials. Among all dental ceramics, zirconia is in evidence as a dental biomaterial and it is the material of choice in contemporary restorative dentistry. Zirconia has been applied as structural material for dental bridges, crowns, inserts, and implants, mostly because of its biocompatibility, high fracture toughness, and radiopacity. However, the clinical success of restorative dentistry has to consider the adhesion to different subs...

  14. Supramolecular biomaterials

    Webber, Matthew J.; Appel, Eric A.; Meijer, E. W.; Langer, Robert

    2016-01-01

    Polymers, ceramics and metals have historically dominated the application of materials in medicine. Yet rationally designed materials that exploit specific, directional, tunable and reversible non-covalent interactions offer unprecedented advantages: they enable modular and generalizable platforms with tunable mechanical, chemical and biological properties. Indeed, the reversible nature of supramolecular interactions gives rise to biomaterials that can sense and respond to physiological cues, or that mimic the structural and functional aspects of biological signalling. In this Review, we discuss the properties of several supramolecular biomaterials, as well as their applications in drug delivery, tissue engineering, regenerative medicine and immunology. We envision that supramolecular biomaterials will contribute to the development of new therapies that combine highly functional materials with unmatched patient- and application-specific tailoring of both material and biological properties.

  15. Bacterial adhesion to titanium-oxy-nitride (TiNOX) coatings with different resistivities : a novel approach for the development of biomaterials

    Koerner, RJ; Butterworth, LA; Mayer, [No Value; Dasbach, R; Busscher, HJ

    2002-01-01

    In this study the quantitative adhesion of a strain of Staphylococcus epidermidis, Streptococcus mutans and Pseudomonas aeruginosa to and the ease of removal from different TiNOX coatings was investigated by means of a parallel plate flow chamber and in situ image analysis. Quality of adhesion was d

  16. Biological biomaterials

    Jorge-Herrero, E. [Servicio de Cirugia Experimental. Clinica Puerta de Hierro, Madrid (Spain)

    1997-05-01

    There are a number of situations in which substances of biological origin are employed as biomaterials. Most of them are macromolecules derived from isolated connective tissue or the connective tissue itself in membrane form, in both cases, the tissue can be used in its natural form or be chemically treated. In other cases, certain blood vessels can be chemically pretreated and used as vascular prostheses. Proteins such as albumin, collagen and fibrinogen are employed to coat vascular prostheses. Certain polysaccharides have also been tested for use in controlled drug release systems. Likewise, a number of tissues, such as dura mater, bovine pericardium, procine valves and human valves, are used in the preparation of cardiac prostheses. We also use veins from animals or humans in arterial replacement. In none of these cases are the tissues employed dissimilar to the native tissues as they have been chemically modified, becoming a new bio material with different physical and biochemical properties. In short, we find that natural products are being utilized as biomaterials and must be considered as such; thus, it is necessary to study both their chemicobiological and physicomechanical properties. In the present report, we review the current applications, problems and future prospects of some of these biological biomaterials. (Author) 84 refs.

  17. Current Strategies in Cardiovascular Biomaterial Functionalization

    Karla Lehle

    2010-01-01

    Full Text Available Prevention of the coagulation cascade and platelet activation is the foremost demand for biomaterials in contact with blood. In this review we describe the underlying mechanisms of these processes and offer the current state of antithrombotic strategies. We give an overview of methods to prevent protein and platelet adhesion, as well as techniques to immobilize biochemically active molecules on biomaterial surfaces. Finally, recent strategies in biofunctionalization by endothelial cell seeding as well as their possible clinical applications are discussed.

  18. Modulating macrophage response to biomaterials

    Zaveri, Toral

    Macrophages recruited to the site of biomaterial implantation are the primary mediators of the chronic foreign body response to implanted materials. Since foreign body response limits performance and functional life of numerous implanted biomaterials/medical devices, various approaches have been investigated to modulate macrophage interactions with biomaterial surfaces to mitigate this response. In this work we have explored two independent approaches to modulate the macrophage inflammatory response to biomaterials. The first approach targets surface integrins, cell surface receptors that mediate cell adhesion to biomaterials through adhesive proteins spontaneously adsorbed on biomaterial surfaces. The second approach involves surface modification of biomaterials using nanotopographic features since nanotopography has been reported to modulate cell adhesion and viability in a cell type-dependent manner. More specifically, Zinc Oxide (ZnO) nanorod surface was investigated for its role in modulating macrophage adhesion and survival in vitro and foreign body response in vivo. For the first approach, we have investigated the role of integrin Mac-1 and RGD-binding integrins in the in-vivo osteolysis response and macrophage inflammatory processes of phagocytosis as well as inflammatory cytokine secretion in response to particulate biomaterials. We have also investigated the in vivo foreign body response (FBR) to subcutaneously implanted biomaterials by evaluating the thickness of fibrous capsule formed around the implants after 2 weeks of implantation. The role of Mac-1 integrin was isolated using a Mac-1 KO mouse and comparing it to a WT control. The role of RGD binding integrins in FBR was investigated by coating the implanted biomaterial with ELVAX(TM) polymer loaded with Echistatin which contains the RGD sequence. For the in-vivo osteolysis study and to study the in-vitro macrophage response to particulate biomaterials, we used the RGD peptide encapsulated in ELVAX

  19. Studies on biodegradable and crosslinkable poly(castor oil fumarate)/poly(propylene fumarate) composite adhesive as a potential injectable biomaterial.

    Mitha, M K; Jayabalan, M

    2009-12-01

    Biodegradable hydroxyl terminated-poly(castor oil fumarate) (HT-PCF) and poly(propylene fumarate) (HT-PPF) resins were synthesized as an injectable and in situ-cross linkable polyester resins for orthopedic applications. An injectable adhesive formulation containing this resin blend, N-vinyl pyrrolidone (NVP), hydroxy apatite, free radical initiator and accelerator was developed. The Composite adhesives containing the ratio of resin blend and NVP, 2.1:1.5, 2.1:1.2 and 2.1:1.0 set fast with tolerable exothermic temperature as a three dimensionally cross linked toughened material. Crosslink density and mechanical properties of the crosslinked composite increase with increase of NVP. The present crosslinked composite has hydrophilic character and cytocompatibility with L929 fibroblast cells. PMID:18592346

  20. Electrical activity of ferroelectric biomaterials and its effects on the adhesion, growth and enzymatic activity of human osteoblast-like cells

    Vaněk, P.; Kolská, Z.; Luxbacher, T.; García, J. A. L.; Lehocký, M.; Vandrovcová, M.; Bačáková, L.; Petzelt, J.

    2016-05-01

    Ferroelectrics have been, among others, studied as electroactive implant materials. Previous investigations have indicated that such implants induce improved bone formation. If a ferroelectric is immersed in a liquid, an electric double layer and a diffusion layer are formed at the interface. This is decisive for protein adsorption and bioactive behaviour, particularly for the adhesion and growth of cells. The charge distribution can be characterized, in a simplified way, by the zeta potential. We measured the zeta potential in dependence on the surface polarity on poled ferroelectric single crystalline LiNbO3 plates. Both our results and recent results of colloidal probe microscopy indicate that the charge distribution at the surface can be influenced by the surface polarity of ferroelectrics under certain ‘ideal’ conditions (low ionic strength, non-contaminated surface, very low roughness). However, suggested ferroelectric coatings on the surface of implants are far from ideal: they are rough, polycrystalline, and the body fluid is complex and has high ionic strength. In real cases, it can therefore be expected that there is rather low influence of the sign of the surface polarity on the electric diffusion layer and thus on the specific adsorption of proteins. This is supported by our results from studies of the adhesion, growth and the activity of alkaline phosphatase of human osteoblast-like Saos-2 cells on ferroelectric LiNbO3 plates in vitro.

  1. Characterization of Bone Marrow Mononuclear Cells on Biomaterials for Bone Tissue Engineering In Vitro

    Dirk Henrich; René Verboket; Alexander Schaible; Kerstin Kontradowitz; Elsie Oppermann; Brune, Jan C; Christoph Nau; Simon Meier; Halvard Bonig; Ingo Marzi; Caroline Seebach

    2015-01-01

    Bone marrow mononuclear cells (BMCs) are suitable for bone tissue engineering. Comparative data regarding the needs of BMC for the adhesion on biomaterials and biocompatibility to various biomaterials are lacking to a large extent. Therefore, we evaluated whether a surface coating would enhance BMC adhesion and analyze the biocompatibility of three different kinds of biomaterials. BMCs were purified from human bone marrow aspirate samples. Beta tricalcium phosphate (β-TCP, without coating or ...

  2. Preparation of novel functional Mg/O/PCL/ZnO composite biomaterials and their corrosion resistance

    Xi, Zhongxian; Tan, Cui; Xu, Lan; Yang, Na; Li, Qing, E-mail: liqingdswu@163.com

    2015-10-01

    Highlights: • Novel functional Mg/O/PCL/ZnO composite biomaterials were prepared. • The biomaterials were prepared by anodization treatment and dip-coating technique. • The composite biomaterials were smooth and with low porosity. • The prepared biomaterials have good corrosion resistance in SBF. • The composite biomaterials can release zinc ion to promote bone formation. - Abstract: In this study, novel and functional Mg/O/PCL/ZnO (magnesium/anodic film/poly(ε-caprolactone)/zinc oxide) composite biomaterials for enhancing the bioactivity and biocompatibility of the implant was prepared by using anodization treatment and dip-coating technique. The surface morphology, microstructure, adhesion strength and corrosion resistance of the composite biomaterials were investigated using scanning electron microscopy (SEM), adhesion measurements, electrochemical tests and immersion tests respectively. In addition, the biocompatible properties of Mg (magnesium), Mg/PCL (magnesium/poly(ε-caprolactone)) and Mg/O/PCL (magnesium/anodic film/poly(ε-caprolactone)) samples were also investigated. The results show that the Mg/O/PCL/ZnO composite biomaterials were with low porosity and with the ZnO powders dispersed in PCL uniformly. The adhesion tests suggested that Mg/O/PCL/ZnO composite biomaterials had better adhesion strength than that of Mg/PCL composite biomaterials obviously. Besides, an in vitro test for corrosion demonstrated that the Mg/O/PCL/ZnO composite biomaterials had good corrosion resistance and zinc ion was released obviously in SBF.

  3. Preparation of novel functional Mg/O/PCL/ZnO composite biomaterials and their corrosion resistance

    Highlights: • Novel functional Mg/O/PCL/ZnO composite biomaterials were prepared. • The biomaterials were prepared by anodization treatment and dip-coating technique. • The composite biomaterials were smooth and with low porosity. • The prepared biomaterials have good corrosion resistance in SBF. • The composite biomaterials can release zinc ion to promote bone formation. - Abstract: In this study, novel and functional Mg/O/PCL/ZnO (magnesium/anodic film/poly(ε-caprolactone)/zinc oxide) composite biomaterials for enhancing the bioactivity and biocompatibility of the implant was prepared by using anodization treatment and dip-coating technique. The surface morphology, microstructure, adhesion strength and corrosion resistance of the composite biomaterials were investigated using scanning electron microscopy (SEM), adhesion measurements, electrochemical tests and immersion tests respectively. In addition, the biocompatible properties of Mg (magnesium), Mg/PCL (magnesium/poly(ε-caprolactone)) and Mg/O/PCL (magnesium/anodic film/poly(ε-caprolactone)) samples were also investigated. The results show that the Mg/O/PCL/ZnO composite biomaterials were with low porosity and with the ZnO powders dispersed in PCL uniformly. The adhesion tests suggested that Mg/O/PCL/ZnO composite biomaterials had better adhesion strength than that of Mg/PCL composite biomaterials obviously. Besides, an in vitro test for corrosion demonstrated that the Mg/O/PCL/ZnO composite biomaterials had good corrosion resistance and zinc ion was released obviously in SBF

  4. Antibacterial Efficiency of Hydroxyapatite Biomaterials with Biodegradable Polylactic Acid and Polycaprolactone Polymers Saturated with Antibiotics / Bionoārdāmu Polimēru Saturošu Un Ar Antibiotiskajām Vielām Piesūcinātu Biomateriālu Antibakteriālās Efektivitātes Noteikšana

    Kroiča Juta

    2016-08-01

    Full Text Available Infections continue to spread in all fields of medicine, and especially in the field of implant biomaterial surgery, and not only during the surgery, but also after surgery. Reducing the adhesion of bacteria could decrease the possibility of biomaterial-associated infections. Bacterial adhesion could be reduced by local antibiotic release from the biomaterial. In this in vitro study, hydroxyapatite biomaterials with antibiotics and biodegradable polymers were tested for their ability to reduce bacteria adhesion and biofilm development. This study examined the antibacterial efficiency of hydroxyapatite biomaterials with antibiotics and biodegradable polymers against Staphylococcus epidermidis and Pseudomonas aeruginosa. The study found that hydroxyapatite biomaterials with antibiotics and biodegradable polymers show longer antibacterial properties than hydroxyapatite biomaterials with antibiotics against both bacterial cultures. Therefore, the results of this study demonstrated that biomaterials that are coated with biodegradable polymers release antibiotics from biomaterial samples for a longer period of time and may be useful for reducing bacterial adhesion on orthopedic implants.

  5. Biomaterials for cardiac regeneration

    Ruel, Marc

    2015-01-01

    This book offers readers a comprehensive biomaterials-based approach to achieving clinically successful, functionally integrated vasculogenesis and myogenesis in the heart. Coverage is multidisciplinary, including the role of extracellular matrices in cardiac development, whole-heart tissue engineering, imaging the mechanisms and effects of biomaterial-based cardiac regeneration, and autologous bioengineered heart valves. Bringing current knowledge together into a single volume, this book provides a compendium to students and new researchers in the field and constitutes a platform to allow for future developments and collaborative approaches in biomaterials-based regenerative medicine, even beyond cardiac applications. This book also: Provides a valuable overview of the engineering of biomaterials for cardiac regeneration, including coverage of combined biomaterials and stem cells, as well as extracellular matrices Presents readers with multidisciplinary coverage of biomaterials for cardiac repair, including ...

  6. Voltammetry of Medical Biomaterials

    Gulaboski, Rubin; Markovski, Velo

    2015-01-01

    The use of biomaterials in the medicine, dentistry and pharmacy represents probably a major breakthrough in tackling many diseases or disabilities in the last 50 years. We refer to varios techniques that are used for the characterization of the structure and the composition of the biomaterials. Voltammetry is an electrochemical technique that helps mainly in understanding the redox properties of various biomaterials containing some suitable redox centers in their structure. We give in this le...

  7. Biofilm and Dental Biomaterials

    Marit Øilo; Vidar Bakken

    2015-01-01

    All treatment involving the use of biomaterials in the body can affect the host in positive or negative ways. The microbiological environment in the oral cavity is affected by the composition and shape of the biomaterials used for oral restorations. This may impair the patients’ oral health and sometimes their general health as well. Many factors determine the composition of the microbiota and the formation of biofilm in relation to biomaterials such as, surface roughness, surface energy and ...

  8. An introduction to biomaterials

    Hollinger, Jeffrey O

    2011-01-01

    Consensus Definitions, Fundamental Concepts, and a Standardized Approach to Applied Biomaterials Sciences, J.O. HollingerBiology, Biomechanics, Biomaterial Interactions: Wound Healing BiologyCutaneous Wound Pathobiology: Raison d'etre for Tissue Engineering, L.K. Macri and R.A.F. ClarkOsseous Wound Healing, A. Nawab, M. Wong, D. Kwak, L. Schutte, A. Sharma, and J.O. HollingerBiology, Biomechanics, Biomaterial Interactions: Cellular MechanicsCell and Tissue Mechanobiology, W. Guo, P. Alvarez, and Y. WangBiology, Biomechanics, Biomaterial Interactions: Materials-Host InteractionsCell-Material In

  9. Biomaterials for MEMS

    Chiao, Mu

    2011-01-01

    This book serves as a guide for practicing engineers, researchers, and students interested in MEMS devices that use biomaterials and biomedical applications. It is also suitable for engineers and researchers interested in MEMS and its applications but who do not have the necessary background in biomaterials.Biomaterials for MEMS highlights important features and issues of biomaterials that have been used in MEMS and biomedical areas. Hence this book is an essential guide for MEMS engineers or researchers who are trained in engineering institutes that do not provide the background or knowledge

  10. Grand challenge in Biomaterials-wound healing

    Salamone, Joseph C.; Salamone, Ann Beal; Swindle-Reilly, Katelyn; Leung, Kelly Xiaoyu-Chen; McMahon, Rebecca E.

    2016-01-01

    Providing improved health care for wound, burn and surgical patients is a major goal for enhancing patient well-being, in addition to reducing the high cost of current health care treatment. The introduction of new and novel biomaterials and biomedical devices is anticipated to have a profound effect on the future improvement of many deleterious health issues. This publication will discuss the development of novel non-stinging liquid adhesive bandages in healthcare applications developed by R...

  11. Introduction to biomaterials

    Donglu, Shi

    2005-01-01

    This book provides a comprehensive introduction to the fundamentals of biomaterials including ceramics, metals, and polymers.Researchers will benefit from the interdisciplinary perspectives of contributors in diverse areas such as orthopedics, biochemistry, biomedical engineering, materials science, tissue engineering and other related medical fields.Both graduate and undergraduate students will find it a valuable reference on tissue engineering related topics, including biostructures and phase diagrams of complex systems, hard tissue prosthetics, novel biomaterials processing methods, and new

  12. 几种高分子生物材料屏障作用预防肌腱粘连的系统评价%Barrier effects of various high polymer biomaterials on prevention of tendon adhesionA systemic evaluation

    胡金萍

    2009-01-01

    OBJECTIVE:To evaluate the safety of various high polymer biomaterials to prevent tendon adhesion,and analyze whether the improvement of injured degree,toxic and side effects,and slipping function of tendon can influence tendon healing.METHODS:A computer-based online search of CNKI was undertaken to identify randomized controlled articles about the effect of various high polymer biomaterials on tendon adhesion with the keywords of "tendon adhesion,biomaterials,and barrier" from 1990 to 2005.Retrieval data were then extracted and analyzed.RESULTS:Among 11 tests,there were 571 patients with tendon injury and 7 animal models with tendon injury,according to inclusion criteria.After surgery,high polymer biomaterials were used to prevent from adhesion and reduce exogenous adhesion incidence.Following-up results demonstrated that high polymer biomaterials which affected endogenous and exogenous healing of tendon might prevent from tendon adhesion,provide foundation for early controlling passive activity,reduce exogenous adhesion occurrence,improve moving function of tendon,and promote tendon healing.CONCLUSION:Barrier effect of high polymer biomaterials can well prevent from tendon adhesion in clinic,especially intrathecal injection or local injection of sodium hyaluronate has both trophic and lubricant actions in preventing from tendon adhesion.However,other effective indicators and safety need to be further studied due to less including tests and weak evidences.%目的:评价不同高分子生物材料预防肌腱粘连的安全性,分析不同高分子生物材料在预防肌腱粘连中对组织的损伤程度、毒副作用、对肌腱滑移功能的改善,是否影响肌腱愈合等方面的优缺点.方法:以计算机检索方法在检索中国期刊全文数据库中(CNKI:1990/2005)检索关于不同高分子材料预防肌腱粘连的临床研究与实验研究的随机对照实验,检索词为"肌腱粘连、生物材料、屏障".检索后对每项研究的资

  13. Effect of biomaterial properties on bone healing in a rabbit tooth extraction socket model

    Fisher, J.P.; Lalani, Z.; Bossano, C.M.; Brey, E.M.; Demian, N.; Johnston, C.M.; Dean, D.; Jansen, J.A.; Wong, M.E.; Mikos, A.G.

    2004-01-01

    In this work we sought to understand the effect of biomaterial properties upon healing bone tissue. We hypothesized that a hydrophilic polymer gel implanted into a bone tissue defect would impede the healing process owing to the biomaterial's prevention of protein adsorption and thus cell adhesion.

  14. Mechanistic investigation of a hemostatic keratin biomaterial

    Rahmany, Maria Bahawdory

    Traumatic injury leads to more productive years lost than heart disease, cancer and stroke combined. Trauma is often accompanied and complicated by uncontrolled bleeding. Human hair keratin biomaterials have demonstrated efficacy in controlling hemorrhage in both small and large animal models; however little is known about the mechanism by which these proteins aid in blood clotting. Inspection of the amino acid sequence of known keratins shows the presence of several cellular binding motifs, suggesting a possible mechanism and potentially eliminating the need to functionalize the material's surface for cellular interaction. In addition to small animal studies, the hemostatic activity of keratin hydrogels was explored through porcine hemorrhage models representing both a high flow and low flow bleed. In both studies, keratin hydrogels appeared to lead to a significant reduction in blood loss. The promising results from these in vivo studies provided the motivation for this project. The objective of this dissertation work was to assess the mechanism of action of a hemostatic keratin biomaterial, and more broadly assess the biomaterial-cellular interaction(s). It is our hypothesis that keratin biomaterials have the capacity to specifically interact with cells and lead to propagation of intracellular signaling pathway, specifically contributing to hemostasis. Through application of biochemical and molecular tools, we demonstrate here that keratin biomaterials contribute to hemostasis through two probable mechanisms; integrin mediated platelet adhesion and increased fibrin polymerization. Platelets are the major cell type involved in coagulation both by acting as a catalytic surface for the clotting cascade and adhering to extracellular matrix (ECM) proteins providing a soft platelet plug. Because keratin biomaterials have structural and biochemical characteristics similar to ECM proteins, we utilized several adhesion assays to investigate platelet adhesion to keratin

  15. Advanced biomaterials and biodevices

    Tiwari, Ashutosh

    2014-01-01

    Biomaterials are the fastest-growing emerging field of  biodevices. Design and development of biomaterials play a significant role in the diagnosis, treatment, and prevention of diseases. Recently, a variety of scaffolds/carriers have been evaluated for tissue regeneration, drug delivery, sensing and imaging.  Liposomes and microspheres have been developed for sustained delivery. Several anti-cancer drugs have been successfully formulated using biomaterial. The targeting of drugs to certain physiological sites has emerged as a promising tool in the treatment with improved drug bioavailability and reduction of dosing frequency. Biodevices-based targeting of drugs may improve the therapeutic success by limiting the adverse drug effects and resulting in more patient compliance and attaining a higher adherence level. Advanced biodevices hold merit as a drug carrier with high carrier capacity, feasibility of incorporation of both hydrophilic and hydrophobic substances, high stability, as well as the feasibility...

  16. Regenerative biomaterials: a review.

    Banyard, Derek A; Bourgeois, Jenna Martin; Widgerow, Alan D; Evans, Gregory R D

    2015-06-01

    The authors present a review of biomaterials, substances traditionally derived from human or animal tissue or, more recently, biodegradable synthetics modeled after naturally occurring resources. These constructs differ from purely synthetic materials in that they are degraded or incorporated into a host's tissue. These biomaterials include a diverse array of medical products, such as acellular dermal matrix, bone substitutes, and injectables. In this review, the authors examine various clinical applications, including burn reconstruction and wound healing, breast surgery, complex abdominal wall reconstruction, craniofacial repair, and cosmetic surgery. Biomaterials such as acellular dermal matrix have proven beneficial in difficult-to-treat applications; however, more prospective data are needed to determine their true efficacy and cost-effectiveness. PMID:26017603

  17. Biomaterials and magnetism

    D Bahadur; Jyotsnendu Giri

    2003-06-01

    Magnetism plays an important role in different applications of health care. Magnetite (Fe34) is biocompatible and therefore is one of the most extensively used biomaterials for different applications ranging from cell separation and drug delivery to hyperthermia. Other than this, a large number of magnetic materials in bulk as well as in the form of nano particles have been exploited for a variety of medical applications. In this review, we summarize the salient features of clinical applications, where magnetic biomaterials are used. Magnetic intracellular hyperthermia for cancer therapy is discussed in detail.

  18. Biomaterials and therapeutic applications

    Ferraro, Angelo

    2016-03-01

    A number of organic and inorganic, synthetic or natural derived materials have been classified as not harmful for the human body and are appropriate for medical applications. These materials are usually named biomaterials since they are suitable for introduction into living human tissues of prosthesis, as well as for drug delivery, diagnosis, therapies, tissue regeneration and many other clinical applications. Recently, nanomaterials and bioabsorbable polymers have greatly enlarged the fields of application of biomaterials attracting much more the attention of the biomedical community. In this review paper I am going to discuss the most recent advances in the use of magnetic nanoparticles and biodegradable materials as new biomedical tools.

  19. Characterizing biomaterial complexity

    L.A. Clifton

    2009-07-01

    Full Text Available Biomaterials research will always require a range of techniques to examine structure and function on a range of length scales and in a range of settings. Neutron scattering provides a unique way of disentangling the molecular and structural complexity of biomaterials through study of the constituent components. We examine how the technique has been used to study surface immobilized proteins and lipid films, floating lipid bilayers as mimics of in vitro planar membranes, and formation of fibres from solution by insects and spiders.

  20. Ethics in biomaterials research.

    Kashi, Ajay; Saha, Subrata

    2009-01-01

    There have been rapid advances in biomaterials research in the past few decades, which have influenced almost all areas of medicine and dentistry. Many ethical concerns related to the use of biomaterials fabricated from artificial substances including metals, polymers, and ceramics have been raised in the past. Most of these include safety and potential harmful effects on the human body. The development of biomaterials that incorporate biological materials such as cells with more traditional, non-biological materials will likely mean that new ethical questions will arise. With significant advances in molecular and cell biology and nanotechnology, the need for safe and effective therapies will also create unique ethical situations in the future. The use of animals in biomedical research has generated opposition from animal rights groups, which has created new challenges to scientists and researchers that warrant further actions. Responsible research by biomaterial scientists in the future will necessitate the incorporation of many new rules and regulations to the existing code of ethics. These will be necessary if new-age materials from emerging areas of science and technology are going to be morally and ethically acceptable to the scientific community and to society. PMID:20402627

  1. Nanoscale biomaterial interface modification for advanced tissue engineering applications

    Recently, various stem cells, including mesenchymal stem cells (MSCs), have been found to have considerable potential for application in tissue engineering and future advanced therapies due to their biological capability to differentiate into specific lineages. Modified surface properties, such as composition, nano-roughness and wettability, affect the most important processes at the biomaterial interface. The aim of the present is work is to study the stem cells' (MSCs) adhesive potential, morphology, phenotypical characteristics in in vitro tests, and to distinguish betwen the different factors influencing the cell/biomaterial interaction, such as nano-topography, surface chemistry and surface free energy.

  2. Biomaterials engineered for integration

    Lorenzo Moroni

    2008-05-01

    Full Text Available As tissue engineering and regenerative medicine are staged to enter the medical care setting, the integration of these newly formed tissues with themselves and the surrounding natural environment of the treated patients is of paramount importance. Although cells alone have undoubtedly obtained a certain success as therapies for a number of different diseases, it is still unclear whether they form new tissues or they stimulate the local cells to restore tissue continuity. In both cases, the resulting outcome is often poorly connected with the surrounding environment and functionality is impaired after few months. True integration can be achieved by designing smart templates made of biomaterials that not only act as scaffolds for cells to adhere and form new tissue, but also provide cues and signals to promote functional tissue connections. Criteria to engineer biomaterials for integration and methodologies used to assess effective connection with host tissues are reviewed.

  3. Plasma-treated polystyrene surfaces : model surfaces for studying cell-biomaterial interactions

    van Kooten, TG; Spijker, HT; Busscher, HJ

    2004-01-01

    Biocompatibility of biomaterials relates, amongst others, to the absence of adverse cellular reactions and modulation of cell adhesion and subsequent responses. With respect to tissue-engineering applications, most materials need to evoke cell adhesion and spreading, while potentially displaying dif

  4. Biomaterials surface science

    Taubert, Andreas; Rodriguez-Cabello, José Carlos

    2013-01-01

    The book provides an overview of the highly interdisciplinary field of surface science in the context of biological and biomedical applications. The covered topics range from micro- and nanostructuring for imparting functionality in a top-down manner to the bottom-up fabrication of gradient surfaces by self-assembly, from interfaces between biomaterials and living matter to smart, stimuli-responsive surfaces, and from cell and surface mechanics to the elucidation of cell-chip interactions in biomedical devices.

  5. Biomaterials for tendon repair

    Rupal Mehta

    2008-01-01

    Electrospinning biomaterials for tendon repair A single bundle of electrospun submicron polycaprolactone fibres. The team at The University of Manchester believes the material could aid regeneration in tendons. Scientists at The University of Manchester, UK, are investigating the use of electrospun polycaprolactone nanofibres to regenerate damaged tendons. Because the bundle of fibres replicates the morphology of tendon tissue, researchers envisage that the synthetic structure will...

  6. Biomaterials for periodontal regeneration

    Shue, Li; Yufeng, Zhang; Mony, Ullas

    2012-01-01

    Periodontal disease is characterized by the destruction of periodontal tissues. Various methods of regenerative periodontal therapy, including the use of barrier membranes, bone replacement grafts, growth factors and the combination of these procedures have been investigated. The development of biomaterials for tissue engineering has considerably improved the available treatment options above. They fall into two broad classes: ceramics and polymers. The available ceramic-based materials inclu...

  7. Inorganic Biomaterials Characterization

    Kalaskar, D.; Seifalinan, A.; Salmasi, S.; Prinsloo, N.

    2014-01-01

    The biocompatibility of a material is crucial in branding it as a biomaterial. Building on the previous biocompatibility chapter, this chapter mainly focuses on the assessment of biocompatibility. The main aims of biocompatibility assessment are: 1) raw material characterisation; 2) in vitro; and 3) in vivo assessment of materials. Figure 3.1 shows a schematic representation of the components of biocompatibility assessment. This chapter will deal with each of these characterisa...

  8. Biomaterials for craniofacial reconstruction

    Neumann, Andreas

    2009-01-01

    Full Text Available Biomaterials for reconstruction of bony defects of the skull comprise of osteosynthetic materials applied after osteotomies or traumatic fractures and materials to fill bony defects which result from malformation, trauma or tumor resections. Other applications concern functional augmentations for dental implants or aesthetic augmentations in the facial region.For ostheosynthesis, mini- and microplates made from titanium alloys provide major advantages concerning biocompatibility, stability and individual fitting to the implant bed. The necessity of removing asymptomatic plates and screws after fracture healing is still a controversial issue. Risks and costs of secondary surgery for removal face a low rate of complications (due to corrosion products when the material remains in situ. Resorbable osteosynthesis systems have similar mechanical stability and are especially useful in the growing skull.The huge variety of biomaterials for the reconstruction of bony defects makes it difficult to decide which material is adequate for which indication and for which site. The optimal biomaterial that meets every requirement (e.g. biocompatibility, stability, intraoperative fitting, product safety, low costs etc. does not exist. The different material types are (autogenic bone and many alloplastics such as metals (mainly titanium, ceramics, plastics and composites. Future developments aim to improve physical and biological properties, especially regarding surface interactions. To date, tissue engineered bone is far from routine clinical application.

  9. Biomaterials in tissue engineering.

    Hubbell, J A

    1995-06-01

    Biomaterials play a pivotal role in field of tissue engineering. Biomimetic synthetic polymers have been created to elicit specific cellular functions and to direct cell-cell interactions both in implants that are initially cell-free, which may serve as matrices to conduct tissue regeneration, and in implants to support cell transplantation. Biomimetic approaches have been based on polymers endowed with bioadhesive receptor-binding peptides and mono- and oligosaccharides. These materials have been patterned in two- and three-dimensions to generate model multicellular tissue architectures, and this approach may be useful in future efforts to generate complex organizations of multiple cell types. Natural polymers have also played an important role in these efforts, and recombinant polymers that combine the beneficial aspects of natural polymers with many of the desirable features of synthetic polymers have been designed and produced. Biomaterials have been employed to conduct and accelerate otherwise naturally occurring phenomena, such as tissue regeneration in wound healing in the otherwise healthy subject; to induce cellular responses that might not be normally present, such as healing in a diseased subject or the generation of a new vascular bed to receive a subsequent cell transplant; and to block natural phenomena, such as the immune rejection of cell transplants from other species or the transmission of growth factor signals that stimulate scar formation. This review introduces the biomaterials and describes their application in the engineering of new tissues and the manipulation of tissue responses. PMID:9634795

  10. Bacterial adhesion to orthopaedic implant materials and a novel oxygen plasma modified PEEK surface

    Rochford, E. T. J.; Poulsson, A. H. C.; Salavarrieta Varela, J.; Lezuo, P.; Richards, R. G.; Moriarty, T. F.

    2014-01-01

    Despite extensive use of polyetheretherketone (PEEK) in biomedical applications, information about bacterial adhesion to this biomaterial is limited. This study investigated Staphylococcus aureus and Staphylococcus epidermidis adhesion to injection moulded and machined PEEK OPTIMA (R) using a custom

  11. Grand challenge in Biomaterials-wound healing.

    Salamone, Joseph C; Salamone, Ann Beal; Swindle-Reilly, Katelyn; Leung, Kelly Xiaoyu-Chen; McMahon, Rebecca E

    2016-06-01

    Providing improved health care for wound, burn and surgical patients is a major goal for enhancing patient well-being, in addition to reducing the high cost of current health care treatment. The introduction of new and novel biomaterials and biomedical devices is anticipated to have a profound effect on the future improvement of many deleterious health issues. This publication will discuss the development of novel non-stinging liquid adhesive bandages in healthcare applications developed by Rochal Industries. The scientists/engineers at Rochal have participated in commercializing products in the field of ophthalmology, including rigid gas permeable contact lenses, soft hydrogel contact lenses, silicone hydrogel contact lenses, contact lens care solutions and cleaners, intraocular lens materials, intraocular controlled drug delivery, topical/intraocular anesthesia, and in the field of wound care, as non-stinging, spray-on liquid bandages to protect skin from moisture and body fluids and medical adhesive-related skin injuries. Current areas of entrepreneurial activity at Rochal Industries pertain to the development of new classes of biomaterials for wound healing, primarily in regard to microbial infection, chronic wound care, burn injuries and surgical procedures, with emphasis on innovation in product creation, which include cell-compatible substrates/scaffolds for wound healing, antimicrobial materials for opportunistic pathogens and biofilm reduction, necrotic wound debridement, scar remediation, treatment of diabetic ulcers, amelioration of pressure ulcers, amelioration of neuropathic pain and adjuvants for skin tissue substitutes. PMID:27047680

  12. Sugared biomaterial binding lectins: achievements and perspectives.

    Bojarová, P; Křen, V

    2016-07-19

    Lectins, a distinct group of glycan-binding proteins, play a prominent role in the immune system ranging from pathogen recognition and tuning of inflammation to cell adhesion or cellular signalling. The possibilities of their detailed study expanded along with the rapid development of biomaterials in the last decade. The immense knowledge of all aspects of glycan-lectin interactions both in vitro and in vivo may be efficiently used in bioimaging, targeted drug delivery, diagnostic and analytic biological methods. Practically applicable examples comprise photoluminescence and optical biosensors, ingenious three-dimensional carbohydrate microarrays for high-throughput screening, matrices for magnetic resonance imaging, targeted hyperthermal treatment of cancer tissues, selective inhibitors of bacterial toxins and pathogen-recognising lectin receptors, and many others. This review aims to present an up-to-date systematic overview of glycan-decorated biomaterials promising for interactions with lectins, especially those applicable in biology, biotechnology or medicine. The lectins of interest include galectin-1, -3 and -7 participating in tumour progression, bacterial lectins from Pseudomonas aeruginosa (PA-IL), E. coli (Fim-H) and Clostridium botulinum (HA33) or DC-SIGN, receptors of macrophages and dendritic cells. The spectrum of lectin-binding biomaterials covered herein ranges from glycosylated organic structures, calixarene and fullerene cores over glycopeptides and glycoproteins, functionalised carbohydrate scaffolds of cyclodextrin or chitin to self-assembling glycopolymer clusters, gels, micelles and liposomes. Glyconanoparticles, glycan arrays, and other biomaterials with a solid core are described in detail, including inorganic matrices like hydroxyapatite or stainless steel for bioimplants. PMID:27075026

  13. Integrated Biomaterials in Tissue Engineering

    Ramalingam, Murugan; Ramakrishna, Seeram; Kobayashi, Hisatoshi; Haikel, Youssef

    2012-01-01

    "Integrated Biomaterials in Tissue Engineering" features all aspects from fundamental principles to current technological advances in biomaterials at the macro/micro/nano/molecular scales suitable for tissue engineering and regenerative medicine. The book is unique as it provides all important aspects dealing with the basic science involved in structure and properties, techniques and technological innovations in material processing and characterizations, and applications of biomaterials in tissue engineering and regenerative medicine.

  14. In vitro evaluation of three different biomaterials as scaffolds for canine mesenchymal stem cells

    Oduvaldo Câmara Marques Pereira-Junior

    2013-05-01

    Full Text Available PURPOSE: To evaluate in vitro ability the of three different biomaterials - purified hydroxyapatite, demineralized bone matrix and castor oil-based polyurethane - as biocompatible 3D scaffolds for canine bone marrow mesenchymal stem cell (MSC intending bone tissue engineering. METHODS: MSCs were isolated from canine bone marrow, characterized and cultivated for seven days with the biomaterials. Cell proliferation and adhesion to the biomaterial surface were evaluated by scanning electron microscopy while differentiation into osteogenic lineage was evaluated by Alizarin Red staining and Sp7/Osterix surface antibody marker. RESULTS: The biomaterials allowed cellular growth, attachment and proliferation. Osteogenic differentiation occurred in the presence of hydroxyapatite, and matrix deposition commenced in the presence of the castor oil-based polyurethane. CONCLUSION: All the tested biomaterials may be used as mesenchymal stem cell scaffolds in cell-based orthopedic reconstructive therapy.

  15. Biomaterials. The Behavior of Stainless Steel as a Biomaterial

    Sanda VISAN

    2011-06-01

    Full Text Available The biomaterials belong to the broad range of biocompatible chemical substances (sometimes even an element, which can be used for a period of time to treat or replace a tissue, organ or function of the human body. These materials bring many advantages in the diagnosis, prevention and medical therapy, reducing downtime for patients, restoring their biological functions, improving hospital management. The market in Romania sells a wide range of biomaterials for dental, cardiovascular medicine, renal, etc. Scientific research contributes to the discovery of new biomaterials or testing known biomaterials, for finding new applications. The paper exemplifies this contribution by presenting the testing of passive stainless steel behaviour in albumin solution using technique of cyclic voltammetry. It was shown that passivation contribute to increased stability of stainless steel implants to corrosive body fluids.

  16. Calcium Phosphate Biomaterials: An Update

    2005-01-01

    Current calcium phosphate (CaP) biomaterials for bone repair, substitution, augmentation and regeneration include hydroxyapatite ( HA ) from synthetic or biologic origin, beta-tricalcium phosphate ( β-TCP ) , biphasic calcium phosphate (BCP), and are available as granules, porous blocks, components of composites (CaP/polymer) cements, and as coatings on orthopedic and dental implants. Experimental calcium phosphate biomaterials include CO3- and F-substituted apatites, Mg-and Zn-substituted β-TCP, calcium phosphate glasses. This paper is a brief review of the different types of CaP biomaterials and their properties such as bioactivity, osteoconductivity, osteoinductivity.

  17. Self-healing biomaterials(3)

    Brochu, Alice B. W.; Craig, Stephen L.; Reichert, William M.

    2010-01-01

    The goal of this review is to introduce the biomaterials community to the emerging field of self-healing materials, and also to suggest how one could utilize and modify self-healing approaches to develop new classes of biomaterials. A brief discussion of the in vivo mechanical loading and resultant failures experienced by biomedical implants is followed by presentation of the self-healing methods for combating mechanical failure. If conventional composite materials that retard failure may be ...

  18. Microgel mechanics in biomaterial design.

    Saxena, Shalini; Hansen, Caroline E; Lyon, L Andrew

    2014-08-19

    The field of polymeric biomaterials has received much attention in recent years due to its potential for enhancing the biocompatibility of systems and devices applied to drug delivery and tissue engineering. Such applications continually push the definition of biocompatibility from relatively straightforward issues such as cytotoxicity to significantly more complex processes such as reducing foreign body responses or even promoting/recapitulating natural body functions. Hydrogels and their colloidal analogues, microgels, have been and continue to be heavily investigated as viable materials for biological applications because they offer numerous, facile avenues in tailoring chemical and physical properties to approach biologically harmonious integration. Mechanical properties in particular are recently coming into focus as an important manner in which biological responses can be altered. In this Account, we trace how mechanical properties of microgels have moved into the spotlight of research efforts with the realization of their potential impact in biologically integrative systems. We discuss early experiments in our lab and in others focused on synthetic modulation of particle structure at a rudimentary level for fundamental drug delivery studies. These experiments elucidated that microgel mechanics are a consequence of polymer network distribution, which can be controlled by chemical composition or particle architecture. The degree of deformability designed into the microgel allows for a defined response to an imposed external force. We have studied deformation in packed colloidal phases and in translocation events through confined pores; in all circumstances, microgels exhibit impressive deformability in response to their environmental constraints. Microgels further translate their mechanical properties when assembled in films to the properties of the bulk material. In particular, microgel films have been a large focus in our lab as building blocks for self

  19. Host response to biomaterials the impact of host response on biomaterial selection

    Badylak, Stephen F

    2015-01-01

    Host Response to Biomaterials: The Impact of Host Response on Biomaterial Selection explains the various categories of biomaterials and their significance for clinical applications, focusing on the host response to each biomaterial. It is one of the first books to connect immunology and biomaterials with regard to host response. The text also explores the role of the immune system in host response, and covers the regulatory environment for biomaterials, along with the benefits of synthetic versus natural biomaterials, and the transition from simple to complex biomaterial solutions. Fiel

  20. Characterization of bone marrow mononuclear cells on biomaterials for bone tissue engineering in vitro.

    Henrich, Dirk; Verboket, René; Schaible, Alexander; Kontradowitz, Kerstin; Oppermann, Elsie; Brune, Jan C; Nau, Christoph; Meier, Simon; Bonig, Halvard; Marzi, Ingo; Seebach, Caroline

    2015-01-01

    Bone marrow mononuclear cells (BMCs) are suitable for bone tissue engineering. Comparative data regarding the needs of BMC for the adhesion on biomaterials and biocompatibility to various biomaterials are lacking to a large extent. Therefore, we evaluated whether a surface coating would enhance BMC adhesion and analyze the biocompatibility of three different kinds of biomaterials. BMCs were purified from human bone marrow aspirate samples. Beta tricalcium phosphate (β-TCP, without coating or coated with fibronectin or human plasma), demineralized bone matrix (DBM), and bovine cancellous bone (BS) were assessed. Seeding efficacy on β-TCP was 95% regardless of the surface coating. BMC demonstrated a significantly increased initial adhesion on DBM and β-TCP compared to BS. On day 14, metabolic activity was significantly increased in BMC seeded on DBM in comparison to BMC seeded on BS. Likewise increased VEGF-synthesis was observed on day 2 in BMC seeded on DBM when compared to BMC seeded on BS. The seeding efficacy of BMC on uncoated biomaterials is generally high although there are differences between these biomaterials. Beta-TCP and DBM were similar and both superior to BS, suggesting either as suitable materials for spatial restriction of BMC used for regenerative medicine purposes in vivo. PMID:25802865

  1. Characterization of Bone Marrow Mononuclear Cells on Biomaterials for Bone Tissue Engineering In Vitro

    Dirk Henrich

    2015-01-01

    Full Text Available Bone marrow mononuclear cells (BMCs are suitable for bone tissue engineering. Comparative data regarding the needs of BMC for the adhesion on biomaterials and biocompatibility to various biomaterials are lacking to a large extent. Therefore, we evaluated whether a surface coating would enhance BMC adhesion and analyze the biocompatibility of three different kinds of biomaterials. BMCs were purified from human bone marrow aspirate samples. Beta tricalcium phosphate (β-TCP, without coating or coated with fibronectin or human plasma, demineralized bone matrix (DBM, and bovine cancellous bone (BS were assessed. Seeding efficacy on β-TCP was 95% regardless of the surface coating. BMC demonstrated a significantly increased initial adhesion on DBM and β-TCP compared to BS. On day 14, metabolic activity was significantly increased in BMC seeded on DBM in comparison to BMC seeded on BS. Likewise increased VEGF-synthesis was observed on day 2 in BMC seeded on DBM when compared to BMC seeded on BS. The seeding efficacy of BMC on uncoated biomaterials is generally high although there are differences between these biomaterials. Beta-TCP and DBM were similar and both superior to BS, suggesting either as suitable materials for spatial restriction of BMC used for regenerative medicine purposes in vivo.

  2. Macrophages, Foreign Body Giant Cells and Their Response to Implantable Biomaterials

    Zeeshan Sheikh

    2015-08-01

    Full Text Available All biomaterials, when implanted in vivo, elicit cellular and tissue responses. These responses include the inflammatory and wound healing responses, foreign body reactions, and fibrous encapsulation of the implanted materials. Macrophages are myeloid immune cells that are tactically situated throughout the tissues, where they ingest and degrade dead cells and foreign materials in addition to orchestrating inflammatory processes. Macrophages and their fused morphologic variants, the multinucleated giant cells, which include the foreign body giant cells (FBGCs are the dominant early responders to biomaterial implantation and remain at biomaterial-tissue interfaces for the lifetime of the device. An essential aspect of macrophage function in the body is to mediate degradation of bio-resorbable materials including bone through extracellular degradation and phagocytosis. Biomaterial surface properties play a crucial role in modulating the foreign body reaction in the first couple of weeks following implantation. The foreign body reaction may impact biocompatibility of implantation devices and may considerably impact short- and long-term success in tissue engineering and regenerative medicine, necessitating a clear understanding of the foreign body reaction to different implantation materials. The focus of this review article is on the interactions of macrophages and foreign body giant cells with biomaterial surfaces, and the physical, chemical and morphological characteristics of biomaterial surfaces that play a role in regulating the foreign body response. Events in the foreign body response include protein adsorption, adhesion of monocytes/macrophages, fusion to form FBGCs, and the consequent modification of the biomaterial surface. The effect of physico-chemical cues on macrophages is not well known and there is a complex interplay between biomaterial properties and those that result from interactions with the local environment. By having a

  3. Abdominal Adhesions

    ... adhesions? Abdominal adhesions can cause intestinal obstruction and female infertility—the inability to become pregnant after a year of trying. Abdominal adhesions can lead to female infertility by preventing fertilized eggs from reaching the uterus, ...

  4. Radiation produced biomaterials

    Medical advances that have prolonged the average life span have generated increased need for new materials that can be used as tissue and organ replacements, drug delivery systems and/or components of devices related to therapy and diagnosis. The first man-made plastic used as surgical implant was celluloid, applied for cranial defect repair. However, the first users applied commercial materials with no regard for their purity, biostability and post-operative interaction with the organism. Thus, these materials evoked a strong tissue reaction and were unacceptable. The first polymer which gained acceptance for man-made plastic was poly(methyl methacrylate). But the first polymer of choice, precursor of the broad class of materials known today as hydrogels, was poly(hydroxyethyl methacrylate) synthesized in the fifties by Wichterle and Lim. HEMA and its various combinations with other, both hydrophilic and hydrophobic, polymers are till now the most often used hydrogels for medical purposes. In the early fifties, the pioneers of the radiation chemistry of polymers began some experiments with radiation crosslinking, also with hydrophilic polymers. However, hydrogels were analyzed mainly from the point of view of phenomena associated with mechanism of reactions, topology of network, and relations between radiation parameters of the processes. Fundamental monographs on radiation polymer physics and chemistry written by Charlesby (1960) and Chapiro (1962) proceed from this time. The noticeable interest in application of radiation to obtain hydrogels for biomedical purposes began in the late sixties as a result of the papers and patents published by Japanese and American scientists. Among others, the team of the Takasaki Radiation Chemistry Research Establishment headed by Kaetsu as well as Hoffman and his colleagues from the Center of Bioengineering, University of Washington have created the base for spreading interest in the field of biomaterials formed by means of

  5. Development of biomaterial scaffold for nerve tissue engineering: Biomaterial mediated neural regeneration

    Sethuraman Swaminathan

    2009-11-01

    Full Text Available Abstract Neural tissue repair and regeneration strategies have received a great deal of attention because it directly affects the quality of the patient's life. There are many scientific challenges to regenerate nerve while using conventional autologous nerve grafts and from the newly developed therapeutic strategies for the reconstruction of damaged nerves. Recent advancements in nerve regeneration have involved the application of tissue engineering principles and this has evolved a new perspective to neural therapy. The success of neural tissue engineering is mainly based on the regulation of cell behavior and tissue progression through the development of a synthetic scaffold that is analogous to the natural extracellular matrix and can support three-dimensional cell cultures. As the natural extracellular matrix provides an ideal environment for topographical, electrical and chemical cues to the adhesion and proliferation of neural cells, there exists a need to develop a synthetic scaffold that would be biocompatible, immunologically inert, conducting, biodegradable, and infection-resistant biomaterial to support neurite outgrowth. This review outlines the rationale for effective neural tissue engineering through the use of suitable biomaterials and scaffolding techniques for fabrication of a construct that would allow the neurons to adhere, proliferate and eventually form nerves.

  6. Chitin fulfilling a biomaterials promise

    Khor, Eugene

    2001-01-01

    The second edition of Chitin underscores the important factors for standardizing chitin processing and characterization. It captures the essential interplay between chitin's assets and limitations as a biomaterial, placing the past promises of chitin in perspective, addressing its present realities and offering insight into what is required to realize chitin's destiny (including its derivative, chitosan) as a biomaterial of the twenty-first century. This book is an ideal guide for both industrialists and researchers with a vested interest in commercializing chitin.An upd

  7. 3D Biomaterial Microarrays for Regenerative Medicine

    Gaharwar, Akhilesh K.; Arpanaei, Ayyoob; Andresen, Thomas Lars;

    2015-01-01

    Three dimensional (3D) biomaterial microarrays hold enormous promise for regenerative medicine because of their ability to accelerate the design and fabrication of biomimetic materials. Such tissue-like biomaterials can provide an appropriate microenvironment for stimulating and controlling stem...

  8. Integrated Biomaterials for Biomedical Technology

    Ramalingam, Murugan; Ramakrishna, Seeram; Kobayashi, Hisatoshi

    2012-01-01

    This cutting edge book provides all the important aspects dealing with the basic science involved in materials in biomedical technology, especially structure and properties, techniques and technological innovations in material processing and characterizations, as well as the applications. The volume consists of 12 chapters written by acknowledged experts of the biomaterials field and covers a wide range of topics and applications.

  9. Inorganic biomaterials structure, properties and applications

    Zhang, Xiang C

    2014-01-01

    This book provides a practical guide to the use and applications of inorganic biomaterials. It begins by introducing the concept of inorganic biomaterials, which includes bioceramics and bioglass. This concept is further extended to hybrid biomaterials consisting of inorganic and organic materials to mimic natural biomaterials. The book goes on to provide the reader with information on biocompatibility, bioactivity and bioresorbability. The concept of the latter is important because of the increasing role resorbable biomaterials are playing in implant applications. The book also introduces a n

  10. Adherence ability of Staphylococcus epidermidis on prosthetic biomaterials: an in vitro study

    Shida T

    2013-10-01

    Full Text Available Takayuki Shida,1 Hironobu Koseki,1 Itaru Yoda,1 Hidehiko Horiuchi,1 Hideyuki Sakoda,2 Makoto Osaki11Department of Orthopedic Surgery, Graduate School of Medicine, Nagasaki University, Nagasaki, Japan; 2Division of Medical Devices, National Institute of Health Sciences, Tokyo, JapanAbstract: Bacterial adhesion to the surface of biomaterials is an essential step in the pathogenesis of implant-related infections. In this in vitro research, we evaluated the ability of Staphylococcus epidermidis to adhere to the surface of solid biomaterials, including oxidized zirconium-niobium alloy (Oxinium, cobalt-chromium-molybdenum alloy, titanium alloy, commercially pure titanium, and stainless steel, and performed a biomaterial-to-biomaterial comparison. The test specimens were physically analyzed to quantitatively determine the viable adherent density of the S. epidermidis strain RP62A (American Type Culture Collection [ATCC] 35984. Field emission scanning electron microscope and laser microscope examination revealed a featureless, smooth surface in all specimens (average roughness <10 nm. The amounts of S. epidermidis that adhered to the biomaterial were significantly lower for Oxinium and the cobalt-chromium-molybdenum alloy than for commercially pure titanium. These results suggest that Oxinium and cobalt-chromium-molybdenum alloy are less susceptible to bacterial adherence and are less inclined to infection than other materials of a similar degree of smoothness.Keyword: bacterial adhesion, implant, infection, surface character

  11. Surface free energy predominates in cell adhesion to hydroxyapatite through wettability.

    Nakamura, Miho; Hori, Naoko; Ando, Hiroshi; Namba, Saki; Toyama, Takeshi; Nishimiya, Nobuyuki; Yamashita, Kimihiro

    2016-05-01

    The initial adhesion of cells to biomaterials is critical in the regulation of subsequent cell behaviors. The purpose of this study was to investigate a mechanism through which the surface wettability of biomaterials can be improved and determine the effects of biomaterial surface characteristics on cellular behaviors. We investigated the surface characteristics of various types of hydroxyapatite after sintering in different atmospheres and examined the effects of various surface characteristics on cell adhesion to study cell-biomaterial interactions. Sintering atmosphere affects the polarization capacity of hydroxyapatite by changing hydroxide ion content and grain size. Compared with hydroxyapatite sintered in air, hydroxyapatite sintered in saturated water vapor had a higher polarization capacity that increased surface free energy and improved wettability, which in turn accelerated cell adhesion. We determined the optimal conditions of hydroxyapatite polarization for the improvement of surface wettability and acceleration of cell adhesion. PMID:26952425

  12. Nanostructured Biomaterials for Tissue Engineered Bone Tissue Reconstruction

    Bressan Eriberto

    2012-01-01

    Full Text Available Bone tissue engineering strategies are emerging as attractive alternatives to autografts and allografts in bone tissue reconstruction, in particular thanks to their association with nanotechnologies. Nanostructured biomaterials, indeed, mimic the extracellular matrix (ECM of the natural bone, creating an artificial microenvironment that promotes cell adhesion, proliferation and differentiation. At the same time, the possibility to easily isolate mesenchymal stem cells (MSCs from different adult tissues together with their multi-lineage differentiation potential makes them an interesting tool in the field of bone tissue engineering. This review gives an overview of the most promising nanostructured biomaterials, used alone or in combination with MSCs, which could in future be employed as bone substitutes. Recent works indicate that composite scaffolds made of ceramics/metals or ceramics/polymers are undoubtedly more effective than the single counterparts in terms of osteoconductivity, osteogenicity and osteoinductivity. A better understanding of the interactions between MSCs and nanostructured biomaterials will surely contribute to the progress of bone tissue engineering.

  13. Physical approaches to biomaterial design

    Mitragotri, Samir; Lahann, Joerg

    2009-01-01

    The development of biomaterials for drug delivery, tissue engineering and medical diagnostics has traditionally been based on new chemistries. However, there is growing recognition that the physical as well as the chemical properties of materials can regulate biological responses. Here, we review this transition with regard to selected physical properties including size, shape, mechanical properties, surface texture and compartmentalization. In each case, we present examples demonstrating the...

  14. Hybrid laser technology for biomaterials

    Jelínek, Miroslav

    Cambridge : Woodhead Publishing Limited, 2013 - (Jelínková, H.), s. 704-724 ISBN 978-0-85709-237-3. - (Woodhead Publishing Series in Electronic and Optical Materials. 37) Institutional support: RVO:68378271 Keywords : laser * biomaterials * coating * hybrid technology * urology * implantology * textile vessel Subject RIV: BM - Solid Matter Physics ; Magnetism https://woodhead.metapress.com/content/h773r34h5x7q7482/resource-secured/?target=fulltext.pdf

  15. Adhesive Categories

    Lack, Stephen; Sobocinski, Pawel

    2003-01-01

    We introduce adhesive categories, which are categories with structure ensuring that pushouts along monomorphisms are well-behaved. Many types of graphical structures used in computer science are shown to be examples of adhesive categories. Double-pushout graph rewriting generalises well to...... rewriting on arbitrary adhesive categories....

  16. Adhesive Categories

    Lack, Stephen; Sobocinski, Pawel

    2004-01-01

    We introduce adhesive categories, which are categories with structure ensuring that pushouts along monomorphisms are well-behaved. Many types of graphical structures used in computer science are shown to be examples of adhesive categories. Double-pushout graph rewriting generalises well to...... rewriting on arbitrary adhesive categories....

  17. Macrophage response to staphylococcal biofilms on crosslinked poly(ethylene glycol polymer coatings and common biomaterials in vitro

    IC Saldarriaga Fernández

    2011-01-01

    Full Text Available Biomaterial-associated-infections (BAI are serious clinical complications that threaten the longevity of implanted devices and lead to high morbidity and mortality. Poly(ethyleneglycol (PEG coatings have been studied as a strategy to reduce the incidence of BAI by reducing protein deposition that promotes pathogen adhesion and growth on device surfaces. Despite their effectiveness to reduce protein adsorption and a hundred-fold reduction in bacterial adhesion, PEG-based coatings still facilitate weak bacterial adhesion that can form an initial basis for biofilms. Here, we describe a methodology enabling direct, quantitative and detailed qualitative in situ observation of macrophage morphology, migration and phagocytosis of bacteria. In vitro interaction of macrophages with Staphylococcus epidermidis 3399 adhering to commercial, crosslinked PEG-based coatings (OptiChem® was compared with fluorinated ethylene propylene, silicone rubber and glass. Adhesion, phagocytosis and migration were studied real-time in a parallel-plate-flow-chamber. Macrophages cultured on OptiChem® coatings showed enhanced migration and phagocytosis of bacteria compared to common biomaterials. Bacterial clearance per macrophage on both inert and reactive OptiChem® coatings were about three times higher than on the common biomaterials studied, corresponding with up to 70% reduction in bacterial numbers on OptiChem®, whereas on the biomaterials less than 40% bacterial reduction was obtained. These findings show that bacterial clearance from cross-linked PEG-based coatings by macrophages is more effective than from common biomaterials, possibly resulting from weak adhesion of bacteria on Optichem®. Moreover, macrophages exhibit higher mobility on Optichem® retaining an improved capability to clear bacteria from larger areas than from other common biomaterials, where they appear more immobilized.

  18. Dynamic biomaterials: toward engineering autonomous feedback.

    Morris, Eliza; Chavez, Michael; Tan, Cheemeng

    2016-06-01

    Dynamic biomaterials are biocompatible engineered systems capable of sensing and actively responding to their surrounding environment. They are of growing interest, both as models in basic research to understand complex cellular systems and in medical applications. Here, we review recent advances in nano-scale and micro-scale biomaterials, specifically artificial cells consisting of compartmentalized biochemical reactions and biologically compatible hydrogels. These dynamic biomaterials respond to stimuli through triggered reactions, reaction cascades, logic gates, and autonomous feedback loops. We outline the advances and remaining challenges in implementing such 'smart' biomaterials capable of autonomously responding to environmental stimuli. PMID:26974245

  19. Biomaterials & scaffolds for tissue engineering

    Fergal J. O'Brien

    2011-03-01

    Full Text Available Every day thousands of surgical procedures are performed to replace or repair tissue that has been damaged through disease or trauma. The developing field of tissue engineering (TE aims to regenerate damaged tissues by combining cells from the body with highly porous scaffold biomaterials, which act as templates for tissue regeneration, to guide the growth of new tissue. This article describes the functional requirements, and types, of materials used in developing state of the art of scaffolds for tissue engineering applications. Furthermore, it describes the challenges and where future research and direction is required in this rapidly advancing field.

  20. Permeability testing of biomaterial membranes

    Dreesmann, L; Hajosch, R; Nuernberger, J Vaz; Schlosshauer, B [NMI Natural and Medical Sciences Institute at University Tuebingen, Markwiesenstr. 55, D-72770 Reutlingen (Germany); Ahlers, M [GELITA AG, Gammelsbacher Str. 2, D-69412 Eberbach (Germany)], E-mail: schlosshauer@nmi.de

    2008-09-01

    The permeability characteristics of biomaterials are critical parameters for a variety of implants. To analyse the permeability of membranes made from crosslinked ultrathin gelatin membranes and the transmigration of cells across the membranes, we combined three technical approaches: (1) a two-chamber-based permeability assay, (2) cell culturing with cytochemical analysis and (3) biochemical enzyme electrophoresis (zymography). Based on the diffusion of a coloured marker molecule in conjunction with photometric quantification, permeability data for a gelatin membrane were determined in the presence or absence of gelatin degrading fibroblasts. Cytochemical evaluation after cryosectioning of the membranes was used to ascertain whether fibroblasts had infiltrated the membrane inside. Zymography was used to investigate the potential release of proteases from fibroblasts, which are known to degrade collagen derivatives such as gelatin. Our data show that the diffusion equilibrium of a low molecular weight dye across the selected gelatin membrane is approached after about 6-8 h. Fibroblasts increase the permeability due to cavity formation in the membrane inside without penetrating the membrane for an extended time period (>21 days in vitro). Zymography indicates that cavity formation is most likely due to the secretion of matrix metalloproteinases. In summary, the combination of the depicted methods promises to facilitate a more rational development of biomaterials, because it provides a rapid means of determining permeability characteristics and bridges the gap between descriptive methodology and the mechanistic understanding of permeability alterations due to biological degradation.

  1. Permeability testing of biomaterial membranes

    The permeability characteristics of biomaterials are critical parameters for a variety of implants. To analyse the permeability of membranes made from crosslinked ultrathin gelatin membranes and the transmigration of cells across the membranes, we combined three technical approaches: (1) a two-chamber-based permeability assay, (2) cell culturing with cytochemical analysis and (3) biochemical enzyme electrophoresis (zymography). Based on the diffusion of a coloured marker molecule in conjunction with photometric quantification, permeability data for a gelatin membrane were determined in the presence or absence of gelatin degrading fibroblasts. Cytochemical evaluation after cryosectioning of the membranes was used to ascertain whether fibroblasts had infiltrated the membrane inside. Zymography was used to investigate the potential release of proteases from fibroblasts, which are known to degrade collagen derivatives such as gelatin. Our data show that the diffusion equilibrium of a low molecular weight dye across the selected gelatin membrane is approached after about 6-8 h. Fibroblasts increase the permeability due to cavity formation in the membrane inside without penetrating the membrane for an extended time period (>21 days in vitro). Zymography indicates that cavity formation is most likely due to the secretion of matrix metalloproteinases. In summary, the combination of the depicted methods promises to facilitate a more rational development of biomaterials, because it provides a rapid means of determining permeability characteristics and bridges the gap between descriptive methodology and the mechanistic understanding of permeability alterations due to biological degradation

  2. Current requirements for polymeric biomaterials in otolaryngology

    Sternberg, Katrin

    2009-01-01

    Full Text Available In recent years otolaryngology was strongly influenced by newly developed implants which are based on both, innovative biomaterials and novel implant technologies. Since the biomaterials are integrated into biological systems they have to fulfill all technical requirements and accommodate biological interactions. Technical functionality relating to implant specific mechanical properties, a sufficiently high stability in terms of physiological conditions, and good biocompatibility are the demands with regard to suitability of biomaterials. The goal in applying biomaterials for implants is to maintain biofunctionality over extended periods of time. These general demands to biomaterials are equally valid for use in otolaryngology. Different classes of materials can be utilized as biomaterials. Metals belong to the oldest biomaterials. In addition, alloys, ceramics, inorganic glasses and composites have been tested successfully. Furthermore, natural and synthetic polymers are widely used materials, which will be in the focus of the current article with regard to their properties and usage as cochlear implants, osteosynthesis implants, stents, and matrices for tissue engineering. Due to their application as permanent or temporary implants materials are differentiated into biostable and biodegradable polymers. The here identified general and up to date requirements for biomaterials and the illustrated applications in otolaryngology emphasize ongoing research efforts in this area and at the same time demonstrate the high significance of interdisciplinary cooperation between natural sciences, engineering, and medical sciences.

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

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

    2007-01-01

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

  4. Micropatterning cell adhesion on polyacrylamide hydrogels.

    Zhang, Jian; Guo, Wei-Hui; Rape, Andrew; Wang, Yu-Li

    2013-01-01

    Cell shape and substrate rigidity play critical roles in regulating cell behaviors and fate. Controlling cell shape on elastic adhesive materials holds great promise for creating a physiologically relevant culture environment for basic and translational research and clinical applications. However, it has been technically challenging to create high-quality adhesive patterns on compliant substrates. We have developed an efficient and economical method to create precise micron-scaled adhesive patterns on the surface of a hydrogel (Rape et al., Biomaterials 32:2043-2051, 2011). This method will facilitate the research on traction force generation, cellular mechanotransduction, and tissue engineering, where precise controls of both materials rigidity and adhesive patterns are important. PMID:23955741

  5. Surgical adhesives

    I. A. THOMAZINI-SANTOS

    2001-12-01

    Full Text Available The authors have performed a literature review of surgical adhesives, such as cyanoacrylate, collagen gelatin, and fibrin glue. They have included different types of commercial and non-commercial fibrin sealants and have reported on the different components in these adhesives, such as fibrinogen, cryoprecipitate, bovine thrombin, and thrombin-like fraction of snake venom.

  6. 3D porous biomimetically modified hydrogels supporting stem cells adhesion

    Studenovská, Hana; Vodička, Petr; Proks, Vladimír; Juhásová, Jana; Motlík, Jan; Rypáček, František

    Dublin : National University of Ireland , 2011. s. 119, psiii-630. [Annual Conference of the European Society for Biomaterials /24./. 04.09.2011-08.09.2011, Dublin] R&D Projects: GA MŠk 1M0538 Institutional research plan: CEZ:AV0Z40500505; CEZ:AV0Z50450515 Keywords : porous hydrogel * cell adhesion * polypeptide Subject RIV: FH - Neurology

  7. Biodegradable copolymers carrying cell-adhesion peptide sequences

    Proks, Vladimír; Machová, Luďka; Popelka, Štěpán; Rypáček, František

    Antalya : Ankara University, Tissue Engineering and Biomaterials Laboratory, 2002. s. P-35. [International Symposium on Biomedical Science and Technology BIOMED /9./. 19.09.2002-22.09.2002, Antalya ] R&D Projects: GA AV ČR IAA4050202; GA MŠk LN00A065 Keywords : amphiphilic block copolymers * cell adhesion * biodegradable Subject RIV: CD - Macromolecular Chemistry

  8. A Biodesigned Nanocomposite Biomaterial for Auricular Cartilage Reconstruction.

    Nayyer, Leila; Jell, Gavin; Esmaeili, Ali; Birchall, Martin; Seifalian, Alexander M

    2016-05-01

    Current biomaterials for auricular replacement are associated with high rates of infection and extrusion. The development of new auricular biomaterials that mimic the mechanical properties of native tissue and promote desirable cellular interactions may prevent implant failure. A porous 3D nanocomposite scaffold (NS) based on POSS-PCU (polyhedral oligomeric silsesquioxane nanocage into polycarbonate based urea-urethane) is developed with an elastic modulus similar to native ear. In vitro biological interactions on this NS reveal greater protein adsorption, increased fibroblast adhesion, proliferation, and collagen production compared with Medpor (the current synthetic auricular implant). In vivo, the POSS-PCU with larger pores (NS2; 150-250 μm) have greater tissue ingrowth (≈5.8× and ≈1.4 × increase) than the POSS-PCU with smaller pores (NS1; 100-50 μm) and when compared to Medpor (>100 μm). The NS2 with the larger pores demonstrates a reduced fibrotic encapsulation compared with NS1 and Medpor (≈4.1× and ≈1.6×, respectively; P NS1 (12 weeks postimplantation). The lack of chronic inflammatory response for all materials may indicate that the elastic modulus and pore size of the implant scaffold could be important design considerations for influencing fibrotic responses to auricular and other soft tissue implants. PMID:26992039

  9. Interactions between bone cells and biomaterials: An update.

    Beauvais, Sabrina; Drevelle, Olivier; Jann, Jessica; Lauzon, Marc-Antoine; Foruzanmehr, Mohammadreza; Grenier, Guillaume; Roux, Sophie; Faucheux, Nathalie

    2016-01-01

     As the populations of the Western world become older, they will suffer more and more from bone defects related to osteoporosis (non-union fractures, vertebral damages), cancers (malignant osteolysis) and infections (osteomyelitis). Autografts are usually used to fill these defects, but they have several drawbacks such as morbidity at the donor site and the amount and quality of bone that can be harvested. Recent scientific milestones made in biomaterials development were shown to be promising to overcome these limitations. Cell interactions with biomaterials can be improved by adding at their surface functional groups such as adhesive peptides and/or growth factors. The development of such biomimetic materials able to control bone cell responses can only proceed if it is based on a sound understanding of bone cell behavior and regulation. This review focuses on bone physiology and the regulation of bone cell differentiation and function, and how the latest advances in biomimetic materials can be translated within promising clinical outcomes. PMID:27100704

  10. Biomaterials and Stem Cells in Regenerative Medicine

    Ramalingam, Murugan; Best, Serena

    2012-01-01

    Work in the area of biomaterials and stem cell therapy has revealed great potential for many applications, from the treatment of localized defects and diseases to the repair and replacement of whole organs. Researchers have also begun to develop a better understanding of the cellular environment needed for optimal tissue repair and regeneration. Biomaterials and Stem Cells in Regenerative Medicine explores a range of applications for biomaterials and stem cell therapy and describes recent research on suitable cell scaffolds and substrates for tissue repair and reconstruction. Featuring contrib

  11. Polymeric biomaterials structure and function, v.1

    Dumitriu, Severian

    2013-01-01

    Biomaterials have had a major impact on the practice of contemporary medicine and patient care. Growing into a major interdisciplinary effort involving chemists, biologists, engineers, and physicians, biomaterials development has enabled the creation of high-quality devices, implants, and drug carriers with greater biocompatibility and biofunctionality. The fast-paced research and increasing interest in finding new and improved biocompatible or biodegradable polymers has provided a wealth of new information, transforming this edition of Polymeric Biomaterials into a two-volume set. This volume

  12. Biomaterials in the repair of sports injuries

    Ducheyne, Paul; Mauck, Robert L.; Smith, Douglas H.

    2012-08-01

    The optimal stimulation of tissue regeneration in bone, cartilage and spinal cord injuries involves a judicious selection of biomaterials with tailored chemical compositions, micro- and nanostructures, porosities and kinetic release properties for the delivery of relevant biologically active molecules.

  13. Interactions of Staphylococcus aureus with ultrasoft hydrogel biomaterials.

    Wang, Yi; Guan, Allan; Isayeva, Irada; Vorvolakos, Katherine; Das, Srilekha; Li, Zhenyu; Phillips, K Scott

    2016-07-01

    Ultrasoft biomaterials-polymers, gels, and human soft tissues with an elastic modulus less than ∼100 kPa-are increasingly used in medical devices. While bacterial interactions (adhesion and biofilm formation) have been extensively studied on stiffer materials, little is known about how bacteria colonize ultrasoft materials as a nidus for infection. The goal of this work was to determine how material properties of ultrasoft hydrogels used for dermal fillers might affect pathogenesis of associated infections. We first synthesized a range of polyacrylamide hydrogels (PAAm) with moduli similar to clinically used dermal fillers and characterized the rheological, morphological and porous properties. We then developed a novel microfabricated insert to contain the PAAm in a flow system for quantification of bacterial adhesion and biofilm formation. The rate of adhesion and numbers of adherent Staphylococcus aureus on the surface of PAAm both decreased as the modulus increased. Adhesion was reduced by 3 logs (from 93 × 10(4)/cm(2) to 0.083 × 10(4)/cm(2)) with increasing modulus (from 17 Pa to 654 Pa). However, the number of bacteria in the bulk was the highest within the stiffest gels. This trend was further amplified in subsequent biofilm studies, where interfacial coverage of biofilm decreased as the modulus increased, while the fraction of biofilm in the bulk was the highest within the stiffest gel. The results show significant differences in bacterial colonization of PAAm based on material properties, and reveal how the injection process may unexpectedly create discontinuities that provide a microenvironmental niche for bacterial colonization. PMID:27131630

  14. Engineering bio-adhesive functions in an antimicrobial polymer multilayer

    Functionalization of a biomaterial surface with adhesive ligands is an effective way to promote specific cell adhesion. Ideally, biomaterial for applications in biomedical implants should simultaneously promote host cell adhesion and inhibit bacterial adhesion. Currently, little attention has been paid to the design of antimicrobial biomaterial with selective adhesiveness towards only targeted cells or tissues. In this study, the role of two typical adhesive ligands on the bioadhesion functions of a model antimicrobial film was elucidated. First, an adhesive ligand including an RGD peptide or collagen (CL) was chemically coupled to an antimicrobial polymeric multilayer composed of dextran sulfate (DS) and chitosan (CS). It was demonstrated that the density of RGD and CL immobilized on the DS/CS multilayer ranges between 4 to 137 ng cm−2 and 100 to 1000 ng cm−2, respectively. Then the effect of immobilized RGD or CL on both bacterial and fibroblast adhesion was investigated. By determining the density and morphology of adherent fibroblast on a DS/CS multilayer with or without an adhesive ligand, it was shown that RGD or CL effectively promoted fibroblast adhesion and proliferation in a concentration-dependent manner. Interestingly, the type of adhesive ligands imposed distinct effects in bacterial adhesion. Immobilized RGD did not enhance Staphylococcus aureus and Escherichia coli adhesion on DS/CS multilayers under all concentrations. In contrast, CL triggered significant S. aureus adhesion on DS/CS multilayers even at low surface concentration and when fibroblast adhesion was absent. Moreover, the detachment forces of individual S. aureus on CL coated DS/CS multilayers probed by atomic force microscopy (AFM) was 3 times and 20 times higher than that on the control substrate and on unmodified DS/CS multilayers, respectively. Interestingly, the lowest detachment force of E. coli was found on the CL coated DS/CS multilayers. This study demonstrated the

  15. Medical applications for biomaterials in Bolivia

    Arias, Susan

    2015-01-01

    This book investigates the potential medical benefits natural biomaterials can offer in developing countries by analyzing the case of Bolivia. The book explores the medical and health related applications of Bolivian commodities: quinoa, barley, sugarcane, corn, sorghum and sunflower seeds. This book helps readers better understand some of the key health concerns facing countries like Bolivia and how naturally derived biomaterials and therapeutics could help substantially alleviate many of their problems.

  16. Biomaterials innovation bundling technologies and life

    Styhre, A

    2014-01-01

    Rapid advances in the life sciences means that there is now a far more detailed understanding of biological systems on the cellular, molecular and genetic levels. Sited at the intersection between the life sciences, the engineering sciences and the design sciences, innovations in the biomaterials industry are expected to garner increasing attention and play a key role in future development. This book examines the biomaterials innovations taking place in corporations and in academic research settings today.

  17. Adsorption behavior of heavy metals on biomaterials.

    Minamisawa, Mayumi; Minamisawa, Hiroaki; Yoshida, Shoichiro; Takai, Nobuharu

    2004-09-01

    We have investigated adsorption of Cd(II) and Pb(II) at pH 2-6.7 onto the biomaterials chitosan, coffee, green tea, tea, yuzu, aloe, and Japanese coarse tea, and onto the inorganic adsorbents, activated carbon and zeolite. High adsorptive capabilities were observed for all of the biomaterials at pH 4 and 6.7. In the adsorption of Cd(II), blend coffee, tea, green tea, and coarse tea have comparable loading capacities to activated carbon and zeolite. Although activated carbon, zeolite, and chitosan are utilized in a variety of fields such as wastewater treatment, chemical and metallurgical engineering, and analytical chemistry, these adsorbents are costly. On the other hand, processing of the test biomaterials was inexpensive, and all the biomaterials except for chitosan were able to adsorb large amounts of Pb(II) and Cd(II) ions after a convenient pretreatment of washing with water followed by drying. The high adsorption capability of the biomaterials prepared from plant materials is promising in the development of a novel, low-cost adsorbent. From these results, it is concluded that heavy metal removal using biomaterials would be an effective method for the economic treatment of wastewater. The proposed adsorption method was applied to the determination of amounts of Cd(II) and Pb(II) in water samples. PMID:15373400

  18. Recent advances of biomaterials in biotherapy.

    Li, Ling; He, Zhi-Yao; Wei, Xia-Wei; Wei, Yu-Quan

    2016-06-01

    Biotherapy mainly refers to the intervention and the treatment of major diseases with biotechnologies or bio-drugs, which include gene therapy, immunotherapy (vaccines and antibodies), bone marrow transplantation and stem-cell therapy. In recent years, numerous biomaterials have emerged and were utilized in the field of biotherapy due to their biocompatibility and biodegradability. Generally, biomaterials can be classified into natural or synthetic polymers according to their source, both of which have attracted much attention. Notably, biomaterials-based non-viral gene delivery vectors in gene therapy are undergoing rapid development with the emergence of surface-modified or functionalized materials. In immunotherapy, biomaterials appear to be attractive means for enhancing the delivery efficacy and the potency of vaccines. Additionally, hydrogels and scaffolds are ideal candidates in stem-cell therapy and tissue engineering. In this review, we present an introduction of biomaterials used in above biotherapy, including gene therapy, immunotherapy, stem-cell therapy and tissue engineering. We also highlighted the biomaterials which have already entered the clinical evaluation. PMID:27047675

  19. Sorption of paracetamol onto biomaterials.

    Ferchichi, Maroua; Dhaouadi, Hatem

    2016-01-01

    Pharmaceutical residues released into the environment are posing more and more public health problems. It is worthwhile to study the retention of pharmaceuticals residues by adsorption on solid supports. Batch sorption experiments are intended to identify the adsorption isotherms of the pharmaceutically active ingredient on the biomaterials. The results obtained in this study have shown that the retention possibilities of these compounds by bio-adsorbents (clay and sand) are not significant. The negligible sorption for these media is explained by the low hydrophobicity of paracetamol (Log K(ow) = 0.46). The retention of paracetamol on the dehydrated sewage sludge and on Posidonia oceanica showed a relatively significant adsorption with a maximal quantity of 0.956 mg g(-1) and 1.638 mg g(-1) for the dehydrate sludge and P. oceanica, respectively. On the other hand, the study of paracetamol retention on the powdered activated carbon showed a high adsorption capacity of about 515.27 mg g(-1). Isotherm data show a good fit with Langmuir's model. An infrared analysis is carried out. It shows identical bands before and after adsorption, with some modifications. PMID:27387007

  20. Engineering ECM signals into biomaterials

    Ryan J. Wade

    2012-10-01

    Full Text Available Historically, tissue engineering focused primarily on the delivery of soluble factors within relatively static scaffolds; yet, increasing evidence indicates that the native, dynamic three-dimensional microenvironment is important in guiding cellular behavior. Consequently, there has been a recent emphasis on increasing the biocomplexity of scaffolds to better mimic the natural extracellular matrix (ECM, including the incorporation of adhesion, degradation, and three-dimensional structures. This review aims to describe important features of the natural ECM and highlight how these features are now being incorporated into synthetic materials to control cellular behavior and tissue evolution towards the development of next generation tissue engineering strategies.

  1. Development of a hybrid scaffold with synthetic biomaterials and hydrogel using solid freeform fabrication technology

    Natural biomaterials such as hyaluronic acid, gelatin and collagen provide excellent environments for tissue regeneration. Furthermore, gel-state natural biomaterials are advantageous for encapsulating cells and growth factors. In cell printing technology, hydrogel which contains cells was printed directly to form three-dimensional (3D) structures for tissue or organ regeneration using various types of printers. However, maintaining the 3D shape of the printed structure, which is made only of the hydrogel, is very difficult due to its weak mechanical properties. In this study, we developed a hybrid scaffold consisting of synthetic biomaterials and natural hydrogel using a multi-head deposition system, which is useful in solid freeform fabrication technology. The hydrogel was intentionally infused into the space between the lines of a synthetic biomaterial-based scaffold. The cellular efficacy of the hybrid scaffold was validated using rat primary hepatocytes and a mouse pre-osteoblast MC3T3-E1 cell line. In addition, the collagen hydrogel, which encapsulates cells, was dispensed and the viability of the cells observed. We demonstrated superior effects of the hybrid scaffold on cell adhesion and proliferation and showed the high viability of dispensed cells.

  2. Development of a hybrid scaffold with synthetic biomaterials and hydrogel using solid freeform fabrication technology

    Shim, Jin-Hyung; Park, Min; Park, Jaesung; Cho, Dong-Woo [Department of Mechanical Engineering, POSTECH (Korea, Republic of); Kim, Jong Young, E-mail: dwcho@postech.ac.kr [Department of Mechanical Engineering, Andong National University (Korea, Republic of)

    2011-09-15

    Natural biomaterials such as hyaluronic acid, gelatin and collagen provide excellent environments for tissue regeneration. Furthermore, gel-state natural biomaterials are advantageous for encapsulating cells and growth factors. In cell printing technology, hydrogel which contains cells was printed directly to form three-dimensional (3D) structures for tissue or organ regeneration using various types of printers. However, maintaining the 3D shape of the printed structure, which is made only of the hydrogel, is very difficult due to its weak mechanical properties. In this study, we developed a hybrid scaffold consisting of synthetic biomaterials and natural hydrogel using a multi-head deposition system, which is useful in solid freeform fabrication technology. The hydrogel was intentionally infused into the space between the lines of a synthetic biomaterial-based scaffold. The cellular efficacy of the hybrid scaffold was validated using rat primary hepatocytes and a mouse pre-osteoblast MC3T3-E1 cell line. In addition, the collagen hydrogel, which encapsulates cells, was dispensed and the viability of the cells observed. We demonstrated superior effects of the hybrid scaffold on cell adhesion and proliferation and showed the high viability of dispensed cells.

  3. Marine Structural Biomaterials in Medical Biomimicry.

    Green, David W; Lee, Jong-Min; Jung, Han-Sung

    2015-10-01

    Marine biomaterials display properties, behaviors, and functions that have not been artificially matched in relation to their hierarchical construction, crack-stopping properties, growth adaptation, and energy efficiency. The discovery and understanding of such features that are characteristic of natural biomaterials can be used to manufacture more energy-efficient and lightweight materials. However, a more detailed understanding of the design of natural biomaterials with good performance and the mechanism of their design is required. Far-reaching biomolecular characterization of biomaterials and biostructures from the ocean world is possible with sophisticated analytical methods, such as whole-genome RNA-seq, and de novo transcriptome sequencing and mass spectrophotometry-based sequencing. In combination with detailed material characterization, the elements in newly discovered biomaterials and their properties can be reconstituted into biomimetic or bio-inspired materials. A major aim of harnessing marine biomaterials is their translation into biomimetic counterparts. To achieve full translation, the genome, proteome, and hierarchical material characteristics, and their profiles in space and time, have to be associated to allow for smooth biomimetic translation. In this article, we highlight the novel science of marine biomimicry from a materials perspective. We focus on areas of material design and fabrication that have excelled in marine biological models, such as embedded interfaces, chiral organization, and the use of specialized composite material-on-material designs. Our emphasis is primarily on key materials with high value in healthcare in which we evaluate their future prospects. Marine biomaterials are among the most exquisite and powerful aspects in materials science today. PMID:25905922

  4. Biomaterials and medical devices a perspective from an emerging country

    Hermawan, Hendra

    2016-01-01

    This book presents an introduction to biomaterials with the focus on the current development and future direction of biomaterials and medical devices research and development in Indonesia. It is the first biomaterials book written by selected academic and clinical experts experts on biomaterials and medical devices from various institutions and industries in Indonesia. It serves as a reference source for researchers starting new projects, for companies developing and marketing products and for governments setting new policies. Chapter one covers the fundamentals of biomaterials, types of biomaterials, their structures and properties and the relationship between them. Chapter two discusses unconventional processing of biomaterials including nano-hybrid organic-inorganic biomaterials. Chapter three addresses biocompatibility issues including in vitro cytotoxicity, genotoxicity, in vitro cell models, biocompatibility data and its related failure. Chapter four describes degradable biomaterial for medical implants...

  5. Heterogeneity of Scaffold Biomaterials in Tissue Engineering

    Lauren Edgar

    2016-05-01

    Full Text Available Tissue engineering (TE offers a potential solution for the shortage of transplantable organs and the need for novel methods of tissue repair. Methods of TE have advanced significantly in recent years, but there are challenges to using engineered tissues and organs including but not limited to: biocompatibility, immunogenicity, biodegradation, and toxicity. Analysis of biomaterials used as scaffolds may, however, elucidate how TE can be enhanced. Ideally, biomaterials should closely mimic the characteristics of desired organ, their function and their in vivo environments. A review of biomaterials used in TE highlighted natural polymers, synthetic polymers, and decellularized organs as sources of scaffolding. Studies of discarded organs supported that decellularization offers a remedy to reducing waste of donor organs, but does not yet provide an effective solution to organ demand because it has shown varied success in vivo depending on organ complexity and physiological requirements. Review of polymer-based scaffolds revealed that a composite scaffold formed by copolymerization is more effective than single polymer scaffolds because it allows copolymers to offset disadvantages a single polymer may possess. Selection of biomaterials for use in TE is essential for transplant success. There is not, however, a singular biomaterial that is universally optimal.

  6. Bacterial Adhesion & Blocking Bacterial Adhesion

    Vejborg, Rebecca Munk

    2008-01-01

    parameters, which influence the transition from a planktonic lifestyle to a sessile lifestyle, have been studied. Protein conditioning film formation was found to influence bacterial adhesion and subsequent biofilm formation considerable, and an aqueous extract of fish muscle tissue was shown to...... tract to the microbial flocs in waste water treatment facilities. Microbial biofilms may however also cause a wide range of industrial and medical problems, and have been implicated in a wide range of persistent infectious diseases, including implantassociated microbial infections. Bacterial adhesion is...... the first committing step in biofilm formation, and has therefore been intensely scrutinized. Much however, still remains elusive. Bacterial adhesion is a highly complex process, which is influenced by a variety of factors. In this thesis, a range of physico-chemical, molecular and environmental...

  7. Biomaterials-Based Organic Electronic Devices

    Bettinger, Christopher J.; Bao, Zhenan

    2010-01-01

    Organic electronic devices have demonstrated tremendous versatility in a wide range of applications including consumer electronics, photovoltaics, and biotechnology. The traditional interface of organic electronics with biology, biotechnology, and medicine occurs in the general field of sensing biological phenomena. For example, the fabrication of hybrid electronic structures using both organic semiconductors and bioactive molecules has led to enhancements in sensitivity and specificity within biosensing platforms, which in turn has a potentially wide range of clinical applications. However, the interface of biomolecules and organic semiconductors has also recently explored the potential use of natural and synthetic biomaterials as structural components of electronic devices. The fabrication of electronically active systems using biomaterials-based components has the potential to realize a large set of unique devices including environmentally biodegradable systems and bioresorbable temporary medical devices. This article reviews recent advances in the implementation of biomaterials as structural components in organic electronic devices with a focus on potential applications in biotechnology and medicine. PMID:20607127

  8. Radiation processing for the preparation of biomaterials and polymer electrolytes

    It is known that a radiation processing of polymeric materials has some unique advantages over other chemical and physical processing. For example, the use of toxic chemicals and strict temperature/moisture controls may not be needed during a radiation processing. Furthermore, the shape distortion of a product can be minimized during a radiation curing process. Since sterilization can also be incorporated in the process, a radiation processing could be efficient to manufacture bio material and medical products. In this presentation, our recent research outcomes in the fields of a radiation processing for biomaterials and polymer electrolytes carried out at the Korea Atomic Energy Research Institute (KAERI) are presented. In the field of a bio material production, two radiation sources, Co-60 gamma ray and electron beam are generally utilized to induce a crosslinking of natural or biocompatible synthetic polymers for the preparation of biomaterials, more specifically hydrogels. In this process, an extra process such as a removal process of toxic chemicals and a sterilization process are not necessary. Hydrogels for a wound treatment, ato pic dermatitis treatment, tissue scaffolds, and post-surgical anti-adhesion barriers have been developed or being developed by our research institute. The preparation of polymer electrolytes such as fuel cell membranes and lithium battery separators are also very attractive research fields using a radiation processing. Commercial polymer membranes such as fluoropolymer and polyethylene can be modified by a radiation induced grafting and/or crosslinking process to introduce desired functionalities onto the membranes for a specific purpose. In our research institute, these radiation-treated membranes for a specific purpose. In our research institute, these radiation-treated membranes have been successfully utilized to prepare fuel cell membranes and lithium battery separators with higher ion conductivities and desired mechanical

  9. Facile design of biomaterials by 'click' chemistry

    Hvilsted, Søren

    2012-01-01

    chemistry is elaborated. The present state of creating functional and biologically active surfaces by click chemistry is presented. Finally, conducting surfaces based on an azide‐functionalized polymer with prospective biological sensor potential are introduced. Copyright © 2012 Society of Chemical Industry......The advent of the so‐called ‘click chemistry’ a decade ago has significantly improved the chemical toolbox for producing novel biomaterials. This review focuses primarily on the application of Cu(I)‐catalysed azide–alkyne 1,3‐cycloadditon in the preparation of numerous, diverse biomaterials and...

  10. Regulatory affairs for biomaterials and medical devices

    Amato, Stephen F; Amato, B

    2014-01-01

    All biomaterials and medical devices are subject to a long list of regulatory practises and policies which must be adhered to in order to receive clearance. This book provides readers with information on the systems in place in the USA and the rest of the world. Chapters focus on a series of procedures and policies including topics such as commercialization, clinical development, general good practise manufacturing and post market surveillance.Addresses global regulations and regulatory issues surrounding biomaterials and medical devicesEspecially useful for smaller co

  11. Sustainable Biomaterials: Current Trends, Challenges and Applications

    Girish Kumar Gupta

    2015-12-01

    Full Text Available Biomaterials and sustainable resources are two complementary terms supporting the development of new sustainable emerging processes. In this context, many interdisciplinary approaches including biomass waste valorization and proper usage of green technologies, etc., were brought forward to tackle future challenges pertaining to declining fossil resources, energy conservation, and related environmental issues. The implementation of these approaches impels its potential effect on the economy of particular countries and also reduces unnecessary overburden on the environment. This contribution aims to provide an overview of some of the most recent trends, challenges, and applications in the field of biomaterials derived from sustainable resources.

  12. Sustainable Biomaterials: Current Trends, Challenges and Applications.

    Kumar Gupta, Girish; De, Sudipta; Franco, Ana; Balu, Alina Mariana; Luque, Rafael

    2015-01-01

    Biomaterials and sustainable resources are two complementary terms supporting the development of new sustainable emerging processes. In this context, many interdisciplinary approaches including biomass waste valorization and proper usage of green technologies, etc., were brought forward to tackle future challenges pertaining to declining fossil resources, energy conservation, and related environmental issues. The implementation of these approaches impels its potential effect on the economy of particular countries and also reduces unnecessary overburden on the environment. This contribution aims to provide an overview of some of the most recent trends, challenges, and applications in the field of biomaterials derived from sustainable resources. PMID:26729083

  13. Surface modification and endothelialization of biomaterials as potential scaffolds for vascular tissue engineering applications.

    Ren, Xiangkui; Feng, Yakai; Guo, Jintang; Wang, Haixia; Li, Qian; Yang, Jing; Hao, Xuefang; Lv, Juan; Ma, Nan; Li, Wenzhong

    2015-08-01

    Surface modification and endothelialization of vascular biomaterials are common approaches that are used to both resist the nonspecific adhesion of proteins and improve the hemocompatibility and long-term patency of artificial vascular grafts. Surface modification of vascular grafts using hydrophilic poly(ethylene glycol), zwitterionic polymers, heparin or other bioactive molecules can efficiently enhance hemocompatibility, and consequently prevent thrombosis on artificial vascular grafts. However, these modified surfaces may be excessively hydrophilic, which limits initial vascular endothelial cell adhesion and formation of a confluent endothelial lining. Therefore, the improvement of endothelialization on these grafts by chemical modification with specific peptides and genes is now arousing more and more interest. Several active peptides, such as RGD, CAG, REDV and YIGSR, can be specifically recognized by endothelial cells. Consequently, graft surfaces that are modified by these peptides can exhibit targeting selectivity for the adhesion of endothelial cells, and genes can be delivered by targeting carriers to specific tissues to enhance the promotion and regeneration of blood vessels. These methods could effectively accelerate selective endothelial cell recruitment and functional endothelialization. In this review, recent developments in the surface modification and endothelialization of biomaterials in vascular tissue engineering are summarized. Both gene engineering and targeting ligand immobilization are promising methods to improve the clinical outcome of artificial vascular grafts. PMID:26023741

  14. Amine-functionalized polypyrrole: Inherently cell adhesive conducting polymer.

    Lee, Jae Y; Schmidt, Christine E

    2015-06-01

    Electrically conducting polymers (CPs) have been recognized as novel biomaterials that can electrically communicate with biological systems. For their tissue engineering applications, CPs have been modified to promote cell adhesion for improved interactions between biomaterials and cells/tissues. Conventional approaches to improve cell adhesion involve the surface modification of CPs with biomolecules, such as physical adsorption of cell adhesive proteins and polycationic polymers, or their chemical immobilization; however, these approaches require additional multiple modification steps with expensive biomolecules. In this study, as a simple and effective alternative to such additional biomolecule treatment, we synthesized amine-functionalized polypyrrole (APPy) that inherently presents cell adhesion-supporting positive charges under physiological conditions. The synthesized APPy provides electrical activity in a moderate range and a hydrophilic surface compared to regular polypyrrole (PPy) homopolymers. Under both serum and serum-free conditions, APPy exhibited superior attachment of human dermal fibroblasts and Schwann cells compared to PPy homopolymer controls. Moreover, Schwann cell adhesion onto the APPy copolymer was at least similar to that on poly-l-lysine treated PPy controls. Our results indicate that amine-functionalized CP substrates will be useful to achieve good cell adhesion and potentially electrically stimulate various cells. In addition, amine functionality present on CPs can further serve as a novel and flexible platform to chemically tether various bioactive molecules, such as growth factors, antibodies, and chemical drugs. PMID:25294089

  15. Biomaterials for the Treatment of Alzheimer's Disease.

    Hadavi, Darya; Poot, André A

    2016-01-01

    Alzheimer's disease (AD) as a progressive and fatal neurodegenerative disease represents a huge unmet need for treatment. The low efficacy of current treatment methods is not only due to low drug potency but also due to the presence of various obstacles in the delivery routes. One of the main barriers is the blood-brain barrier. The increasing prevalence of AD and the low efficacy of current therapies have increased the amount of research on unraveling of disease pathways and development of treatment strategies. One of the interesting areas for the latter subject is biomaterials and their applications. This interest originates from the fact that biomaterials are very useful for the delivery of therapeutic agents, such as drugs, proteins, and/or cells, in order to treat diseases and regenerate tissues. Recently, manufacturing of nano-sized delivery systems has increased the efficacy and delivery potential of biomaterials. In this article, we review the latest developments with regard to the use of biomaterials for the treatment of AD, including nanoparticles and liposomes for delivery of therapeutic compounds and scaffolds for cell delivery strategies. PMID:27379232

  16. ICTAS announces thrust on nano-biomaterials

    Nystrom, Lynn A.

    2007-01-01

    Four innovative interdisciplinary programs connecting nanotechnology and health care are receiving initial seed funding from Virginia Tech's Institute for Critical Technology and Applied Science (ICTAS). The four areas will come under one of the designated primary research thrusts within ICTAS, "Nano-Biomaterials for the Delivery of Therapeutic and Diagnostic Agents."

  17. Application of mushroom chitosans in medical biomaterials

    Beran, M.; Urban, M.; Adámek, L.; Jandušík, L.; Spěváček, Jiří

    Snowbird, Utah : Keystone Symposia, 2007. s. 49. [Keystone Symposia: Tissue Engineering and Development Biology. 12.04.2007-17.04.2007, Snowbird] R&D Projects: GA MŠk 2B06173 Institutional research plan: CEZ:AV0Z40500505 Keywords : mushrooms * chitosan * biomaterials Subject RIV: EI - Biotechnology ; Bionics

  18. Silk film biomaterials for ocular surface repair

    Lawrence, Brian David

    Current biomaterial approaches for repairing the cornea's ocular surface upon injury are partially effective due to inherent material limitations. As a result there is a need to expand the biomaterial options available for use in the eye, which in turn will help to expand new clinical innovations and technology development. The studies illustrated here are a collection of work to further characterize silk film biomaterials for use on the ocular surface. Silk films were produced from regenerated fibroin protein solution derived from the Bombyx mori silkworm cocoon. Methods of silk film processing and production were developed to produce consistent biomaterials for in vitro and in vivo evaluation. A wide range of experiments was undertaken that spanned from in vitro silk film material characterization to in vivo evaluation. It was found that a variety of silk film properties could be controlled through a water-annealing process. Silk films were then generated that could be use in vitro to produce stratified corneal epithelial cell sheets comparable to tissue grown on the clinical standard substrate of amniotic membrane. This understanding was translated to produce a silk film design that enhanced corneal healing in vivo on a rabbit injury model. Further work produced silk films with varying surface topographies that were used as a simplified analog to the corneal basement membrane surface in vitro. These studies demonstrated that silk film surface topography is capable of directing corneal epithelial cell attachment, growth, and migration response. Most notably epithelial tissue development was controllably directed by the presence of the silk surface topography through increasing cell sheet migration efficiency at the individual cellular level. Taken together, the presented findings represent a comprehensive characterization of silk film biomaterials for use in ocular surface reconstruction, and indicate their utility as a potential material choice in the

  19. Adhesion and Cohesion

    J. Anthony von Fraunhofer

    2012-01-01

    Full Text Available The phenomena of adhesion and cohesion are reviewed and discussed with particular reference to dentistry. This review considers the forces involved in cohesion and adhesion together with the mechanisms of adhesion and the underlying molecular processes involved in bonding of dissimilar materials. The forces involved in surface tension, surface wetting, chemical adhesion, dispersive adhesion, diffusive adhesion, and mechanical adhesion are reviewed in detail and examples relevant to adhesive dentistry and bonding are given. Substrate surface chemistry and its influence on adhesion, together with the properties of adhesive materials, are evaluated. The underlying mechanisms involved in adhesion failure are covered. The relevance of the adhesion zone and its importance with regard to adhesive dentistry and bonding to enamel and dentin is discussed.

  20. Effect of biomaterial properties on bone healing in a rabbit tooth extraction socket model.

    Fisher, John P; Lalani, Zahid; Bossano, Carla M; Brey, Eric M; Demian, Nagi; Johnston, Carol M; Dean, David; Jansen, John A; Wong, Mark E K; Mikos, Antonios G

    2004-03-01

    In this work we sought to understand the effect of biomaterial properties upon healing bone tissue. We hypothesized that a hydrophilic polymer gel implanted into a bone tissue defect would impede the healing process owing to the biomaterial's prevention of protein adsorption and thus cell adhesion. To test this hypothesis, healing bone was investigated within a rabbit incisor extraction socket, a subcritical size bone defect that resists significant soft tissue invasion by virtue of its conformity. After removal of the incisor teeth, one tooth socket was left as an empty control, one was filled with crosslinked polymer networks formed from the hydrophobic polymer poly(propylene fumarate) (PPF), and one was filled with a hydrogel formed from the hydrophilic oligomer oligo(poly(ethylene glycol) fumarate) (OPF). At five different times (4 days as well as 1, 2, 4, and 8 weeks), jaw bone specimens containing the tooth sockets were removed. We analyzed bone healing by histomorphometrical analysis of hematoxylin and eosin stained sections as well as immunohistochemically stained sections. The proposed hypothesis, that a hydrophilic material would hinder bone healing, was supported by the histomorphometrical results. In addition, the immunohistochemical results reflect molecular signaling indicative of the early invasion of platelets, the vascularization of wound-healing tissue, the differentiation of migrating progenitor cells, and the formation and remodeling of bone tissue. Finally, the results emphasize the need to consider biomaterial properties and their differing effects upon endogenous growth factors, and thus bone healing, during the development of tissue engineering devices. PMID:14762922

  1. A Tubular Biomaterial Construct Exhibiting a Negative Poisson's Ratio.

    Jin Woo Lee

    Full Text Available Developing functional small-diameter vascular grafts is an important objective in tissue engineering research. In this study, we address the problem of compliance mismatch by designing and developing a 3D tubular construct that has a negative Poisson's ratio νxy (NPR. NPR constructs have the unique ability to expand transversely when pulled axially, thereby resulting in a highly-compliant tubular construct. In this work, we used projection stereolithography to 3D-print a planar NPR sheet composed of photosensitive poly(ethylene glycol diacrylate biomaterial. We used a step-lithography exposure and a stitch process to scale up the projection printing process, and used the cut-missing rib unit design to develop a centimeter-scale NPR sheet, which was rolled up to form a tubular construct. The constructs had Poisson's ratios of -0.6 ≤ νxy ≤ -0.1. The NPR construct also supports higher cellular adhesion than does the construct that has positive νxy. Our NPR design offers a significant advance in the development of highly-compliant vascular grafts.

  2. A Tubular Biomaterial Construct Exhibiting a Negative Poisson's Ratio.

    Lee, Jin Woo; Soman, Pranav; Park, Jeong Hun; Chen, Shaochen; Cho, Dong-Woo

    2016-01-01

    Developing functional small-diameter vascular grafts is an important objective in tissue engineering research. In this study, we address the problem of compliance mismatch by designing and developing a 3D tubular construct that has a negative Poisson's ratio νxy (NPR). NPR constructs have the unique ability to expand transversely when pulled axially, thereby resulting in a highly-compliant tubular construct. In this work, we used projection stereolithography to 3D-print a planar NPR sheet composed of photosensitive poly(ethylene) glycol diacrylate biomaterial. We used a step-lithography exposure and a stitch process to scale up the projection printing process, and used the cut-missing rib unit design to develop a centimeter-scale NPR sheet, which was rolled up to form a tubular construct. The constructs had Poisson's ratios of -0.6 ≤ νxy ≤ -0.1. The NPR construct also supports higher cellular adhesion than does the construct that has positive νxy. Our NPR design offers a significant advance in the development of highly-compliant vascular grafts. PMID:27232181

  3. Synthesis and morphological characterization of block copolymers for improved biomaterials

    Biocompatible polymers are known to act as scaffolds for the regeneration and growth of bone. Block copolymers are of interest as scaffold materials because a number of the blocks are biocompatible, and their nanostructure is easily tunable with synthetic techniques. In this paper, we report the synthesis of a novel class of biomaterials from block copolymers containing a hydrophobic block of methyl methacrylate and a hydrophilic block of either acrylic acid, dimethyl acrylamide, or 2-hydroxyethyl methacrylate. The block copolymers were synthesized using a combination of reversible addition-fragmentation chain transfer (RAFT) polymerization and click chemistry. Since the surface morphology is critical for successful cell growth, atomic force microscopy (AFM) studies were conducted for selected block copolymers. The topography, phase angle and friction maps were obtained in dry and physiological buffer environments to study the morphology. Results of AFM imaging identified the presence of polymer domains corresponding to the copolymer components. The distribution of nanoscale features in these block copolymers is comparable to those found on other surfaces that exhibit favorable cell adhesion and growth. In physiological buffer medium, the hydrophilic component of the block copolymer (acrylic acid or hydroxyethyl methacrylate) appears to be present in greater amounts on the surface as a consequence of water absorption and swelling.

  4. Synthesis and morphological characterization of block copolymers for improved biomaterials

    Schricker, Scott, E-mail: Schricker.1@osu.edu [Restorative and Prosthetic Dentistry Section, College of Dentistry, The Ohio State University, Columbus, OH 43210 (United States); Palacio, Manuel [Nanoprobe Laboratory for Bio- and Nanotechnology and Biomimetics, The Ohio State University, Columbus, OH 43210 (United States); Thirumamagal, B.T.S. [Restorative and Prosthetic Dentistry Section, College of Dentistry, The Ohio State University, Columbus, OH 43210 (United States); Bhushan, Bharat [Nanoprobe Laboratory for Bio- and Nanotechnology and Biomimetics, The Ohio State University, Columbus, OH 43210 (United States)

    2010-05-15

    Biocompatible polymers are known to act as scaffolds for the regeneration and growth of bone. Block copolymers are of interest as scaffold materials because a number of the blocks are biocompatible, and their nanostructure is easily tunable with synthetic techniques. In this paper, we report the synthesis of a novel class of biomaterials from block copolymers containing a hydrophobic block of methyl methacrylate and a hydrophilic block of either acrylic acid, dimethyl acrylamide, or 2-hydroxyethyl methacrylate. The block copolymers were synthesized using a combination of reversible addition-fragmentation chain transfer (RAFT) polymerization and click chemistry. Since the surface morphology is critical for successful cell growth, atomic force microscopy (AFM) studies were conducted for selected block copolymers. The topography, phase angle and friction maps were obtained in dry and physiological buffer environments to study the morphology. Results of AFM imaging identified the presence of polymer domains corresponding to the copolymer components. The distribution of nanoscale features in these block copolymers is comparable to those found on other surfaces that exhibit favorable cell adhesion and growth. In physiological buffer medium, the hydrophilic component of the block copolymer (acrylic acid or hydroxyethyl methacrylate) appears to be present in greater amounts on the surface as a consequence of water absorption and swelling.

  5. Atmospheric Microplasma Application for Surface Modification of Biomaterials

    Shimizu, Kazuo; Fukunaga, Hodaka; Tatematsu, Shigeki; Blajan, Marius

    2012-11-01

    Atmospheric microplasma has been intensively studied for applications in various fields, since in this technology the generated field is only 1 kV (approx) under atmospheric pressure and a dielectric barrier discharge gap of 10 to 100 µm. A low discharge voltage atmospheric plasma process is an economical and effective solution for various applications such as indoor air control including sterilization, odor removal, and surface treatment, and would be suitable for medical applications in the field of plasma life sciences. In this paper, we present the application of microplasma for the surface treatment of materials used in medical fields. Moreover, a biomaterial composed of L-lactic acid is used in experiments, which can be biodecomposed in the human body after medical operations. The surface modification process was carried out with active species generated between the microplasma electrodes, which were observed by emission spectrometry. Microplasma treatment of a polymer sheet using Ar as the process gas decreased the contact angle of a water droplet at the surface of the polymer from 78.3 to 45.6° in 10 s, indicating improved surface adhesive characteristics.

  6. Improving biocompatibility by controlling protein adsorption: Modification and design of biomaterials using poly(ethylene glycol) microgels and microspheres

    Scott, Evan Alexander

    2009-12-01

    Guided by the clinical needs of patients and developments in biology and materials science, the primary focus of the biomaterials field remains at the solid/liquid interface between biomaterial surfaces and biological fluids. For blood-contacting devices, biological responses are initially elicited and directed by proteins that adsorb from this multicomponent solution to form thin films on their surfaces. The identity, conformation, and quantity of adsorbed proteins are related to the properties of a material's surface. For example, hydrophobic surfaces tend to be thrombotic via interactions between platelets and adsorbed fibrinogen, while surface-activation of specific enzymes initiates the coagulation cascade on hydrophilic surfaces. The objective of this thesis is to improve the design of biomaterials through the analysis and control of adsorbing protein layers. This goal is approached through three separate strategies. First, a proteomics-based methodology is presented for the assessment of protein conformation at the residue level after adsorption to biomaterial surfaces. A quantitative mass spectrometric technique is additionally suggested for the identification and quantification of proteins within adsorbed protein layers. Second, a method is described for the covalent attachment of poly(ethylene glycol) (PEG)-based hydrogel coatings onto biomaterials surfaces for the minimization of protein adsorption. The coatings are applied using partially crosslinked PEG solutions containing polymer and protein oligomers and microgels that can be designed to control cell adhesion. Finally, a modular strategy is proposed for the assembly of bioactive PEG-based hydrogel scaffolds. This was accomplished using novel PEG microspheres with diverse characteristics that individually contribute to the ability of the scaffold to direct cellular infiltration. The methodologies proposed by this thesis contribute to the recent shift in biomaterials and tissue engineering strategies

  7. Biomaterials in Maxillofacial Surgery: Membranes and Grafts

    Rodella, Luigi F.; Favero, Gaia; Labanca, Mauro

    2011-01-01

    Today, significant differences in the use of biomaterials (membranes and grafts) of animal or synthetic origin have yet to be reported. Nevertheless, some evidences suggest that synthetic materials have a lower risk of disease transmission. This review aims to assess the available informations on regenerative bone technique using reasorbable membranes and bone grafts. In particular, biocompatibility, immunological response, tissue reaction, reabsorption time and histological features of mater...

  8. New nanostructured biomaterials for regenerative medicine

    A. Sgambato

    2016-01-01

    Innovative approaches in tissue engineering and regenerative medicine based on decellularized extracellular matrix (ECM) scaffolds and tissues are quickly growing. ECM proteins are particularly adequate toward tissue regeneration applications, since they are natural biomaterials that can be bio-activated with signalling molecules able to influence cell fate, driving cell responses and tissue regeneration. Indeed, it is well recognized that cells perceive and respond to their microenvironment;...

  9. [The future of biomaterials in urology].

    Grise, Philippe

    2002-12-01

    The fields of application of implanted biomaterials will continue to grow, ranging from the use of catheters and slings for the genitourinary tract, to the production of tissues and organs. The scale of research has changed over recent years, passing from a macroscopic view to a microscopic view, resulting in a change from mechanical devices, such as prostheses, catheters and slings to the cellular unit and more particularly in vitro cell cultures. New techniques, such as gene therapy and cell reconstruction have been recently introduced into the field of urology. Prospective biocompatibility studies must be conducted to establish appropriate biocompatibility standards adapted to new materials. The development of these new materials required a multidisciplinary approach involving engineers, biologists and physicists. It must be conducted in specialized centres skilled in biocompatibility research and in close collaboration with a basic bioscience and clinical practice. In the future, synthetic biomaterials will have an almost unlimited range of mechanical properties allowing much more specific applications. Another improvement of materials will concern a reduction of the risk of infection, erosion, mineral deposits, migration of particles, secondary reactions, and finally improved durability. However, the long-term properties of synthetic materials will probably not be as good as those of natural or almost natural biomaterials derived from biotechnology by tissue engineering. PMID:12545647

  10. Reconstituted Keratin Biomaterial with Enhanced Ductility

    Halleh Atri

    2015-11-01

    Full Text Available Nowadays the waste from protein fibres represents an important renewable source for a new generation of biomaterials and promising competitors for carbohydrate based biomaterials. Regenerated keratin biomaterials are biodegradable in vivo and in vitro, biocompatible, and support cell attachment and proliferation; however, their major drawback has been their weak mechanical properties such as ductility. The following study was conducted in an attempt to improve the ductility of reconstituted keratin films obtained from Australian merino wool fibres. Keratin was extracted from wool fibres according to an established protocol proposed by Yamauchi, and then dialyzed and desalted by multiple diafiltration wash cycles. The resulting keratin film was transparent, biodegradable, and, opposite to its predecessors, mechanically durable, possessing a Young modulus about 12.5 MPa with 35% extensibility. The polypeptide chains were found to rearrange themselves in the β-sheet state in this keratin film, which was shown to be semi-crystalline. This film, unlike its predecessors, did not support human cell proliferation. These properties of the diafiltered keratin film have led us to think that diafiltration resulted in producing a totally new keratin film, which is envisaged to find applications in various areas.

  11. Bacterial adhesion forces with substratum surfaces and the susceptibility of biofilms to antibiotics

    Muszanska, L.H.; Nejadnik, M.R.; Chen, Y.; Heuvel, van den E.R.; Busscher, H.J.; Mei, van der H.C.; Norde, W.

    2012-01-01

    Biofilms causing biomaterial-associated infection resist antibiotic treatment and usually necessitate the replacement of infected implants. Here we relate bacterial adhesion forces and the antibiotic susceptibility of biofilms on uncoated and polymer brush-coated silicone rubber. Nine strains of Sta

  12. Advanced adhesives in electronics

    Bailey, C

    2011-01-01

    Adhesives are widely used in the manufacture of electronic devices to act as passive and active components. Recently there has been considerable interest in the use of conductive adhesives. This book reviews key types of conductive adhesives, processing methods, properties and the way they can be modelled as well as potential applications.$bAdhesives for electronic applications serve important functional and structural purposes in electronic components and packaging, and have developed significantly over the last few decades. Advanced adhesives in electronics reviews recent developments in adhesive joining technology, processing and properties. The book opens with an introduction to adhesive joining technology for electronics. Part one goes on to cover different types of adhesive used in electronic systems, including thermally conductive adhesives, isotropic and anisotropic conductive adhesives and underfill adhesives for flip-chip applications. Part two focuses on the properties and processing of electronic ...

  13. Analysis of the strengthening and toughening of a biomaterial interface

    SONG; Fan

    2001-01-01

    [1]Currey, J. D., Mechanical properties of mother of pearl in tension, Proc. R. Soc. Lond. B, 1977, 196: 443—463.[2]Jackson, A. P., Vincent, J. F. V., Turner, R. M., The mechanical design of nacre, Proc. R. Soc. Lond. B., 1988, 234: 415—440.[3]Wang, R. Z., Wen, H. B., Cui, F. Z. et al., Observations of damage morphologies in nacre during deformation and fracture, J. Mater. Sci., 1995, 30: 2299—2304.[4]Smith, B. L., Schaffer, T. E., Viani, M. et al., Molecular mechanistic origin of the toughness of natural adhesives, fibres and composites, Nature, 1999, 399: 761—763.[5]Addadi, L., Weiner, S., A pavement of pearl, Nature, 1997, 389: 912—915.[6]Schaffer,T. E., Ionescu-Zantti, C., Fritz, M. et al., Does abalone nacre form by heteroepiaxial nucleation or by growth through mineral bridges? Chem. Mater., 1997, 9: 1731—1740.[7]Vincent, J. F. V., Structural Biomaterials, New York; The Macmillan Press Ltd, 1982.[8]Song, F., Bai, Y. L., Effects of mineral bridges on the mechanical properties of nacre, Acta Mechanica Solida Sinica (in Chinese), 2000, 21(Special Issue): 171—176.[9]Szuromi, P., Microstructural engineering of materials, Science, 1997, 277: 1183—1183.[10]Heuer, A. H., Fink, D. J., Laraia, J. L. et al., Innovative materials processing strategies: a biomimetic approach, Science, 1992, 255: 1098—1105.[11]Stupp, S. I., Braun, P. V., Molecular manipulation of microstructure: biomaterials, ceramics, and semiconductors, Science, 1997, 277: 1242—1248.[12]Watabe, N., Crystal growth of calcium carbonate in the invertebrates, Prog. Crystal Growth Charact., 1981, 4: 99—147.[13]Clegg, W. J., Kendall, K., Alford, N. M. et al., A simple way to make tough ceramics, Nature, 1990, 347: 455—457.[14]Jackson, A. P., Vincent, J. F. V., Briggs, D. et al., Application of surface analytical techniques to the study fracture surface of mother-of pearl, J. Mater. Science Letters, 1986, 5: 975—980.[15

  14. Biomimetic oligosaccharide and peptide surfactant polymers designed for cardiovascular biomaterials

    Ruegsegger, Mark Andrew

    A common problem associated with cardiovascular devices is surface induced thrombosis initiated by the rapid, non-specific adsorption of plasma proteins onto the biomaterial surface. Control of the initial protein adsorption is crucial to achieve the desired longevity of the implanted biomaterial. The cell membrane glycocalyx acts as a non-thrombogenic interface through passive (dense oligosaccharide structures) and active (ligand/receptor interactions) mechanisms. This thesis is designed to investigate biomimicry of the cell glycocalyx to minimize non-specific protein adsorption and promote specific ligand/receptor interactions. Biomimetic macromolecules were designed through the molecular-scale engineering of polymer surfactants, utilizing a poly(vinyl amine) (PVAm) backbone to which hydrophilic (dextran, maltose, peptide) and hydrophobic alkyl (hexanoyl or hexanal) chains are simultaneously attached. The structure was controlled through the molar feed ratio of hydrophobic-to-hydrophilic groups, which also provided control of the solution and surface-active properties. To mimic passive properties, a series of oligomaltose surfactants were synthesized with increasing saccharide length (n = 2, 7, 15 where n is number of glucose units) to investigate the effect of coating height on protein adsorption. The surfactants were characterized by infra red (IR) and nuclear magnetic resonance (NMR) spectroscopies for structural properties and atomic force microscopy (AFM) and contact angle goniometry for surface activity. Protein adsorption under dynamic flow (5 dyn/cm2) was reduced by 85%--95% over the bare hydrophobic substrate; platelet adhesion dropped by ˜80% compared to glass. Peptide ligands were incorporated into the oligosaccharide surfactant to promote functional activity of the passive coating. The surfactants were synthesized to contain 0%, 25%, 50%, 75%, and 100% peptide ligand density and were stable on hydrophobic surfaces. The peptide surface density was

  15. Adhesion in microelectronics

    Mittal, K L

    2014-01-01

    This comprehensive book will provide both fundamental and applied aspects of adhesion pertaining to microelectronics in a single and easily accessible source. Among the topics to be covered include; Various theories or mechanisms of adhesionSurface (physical or chemical) characterization of materials as it pertains to adhesionSurface cleaning as it pertains to adhesionWays to improve adhesionUnraveling of interfacial interactions using an array of pertinent techniquesCharacterization of interfaces / interphasesPolymer-polymer adhesionMetal-polymer adhesion  (metallized polymers)Polymer adhesi

  16. The case study of biomaterials and biominerals

    Del Hoyo Martínez, Carmen

    2013-04-01

    The teaching of biomaterials as case study by on-line platform , susceptible to develop both individually and in groups, got different objectives proposed by the European Higher Education System, among which include: participate actively in the teaching-learning process by students, interpreting situations, adapt processes and solutions. It also improves oral and written communication, analytical skills and synthesis and also the ability to think critically. Biomaterials have their origin in biominerals. These are solid inorganic compounds of defined structure, consisting of molecular control mechanisms that operate in biological systems. Its main functions are: structural support, a reservoir of essential elements, sensors, mechanical protection and storage of toxic elements. Following the demand of materials compatible with certain functional systems of our body, developed biomaterials. Always meet the condition of biocompatibility. Should be tolerated by the body and do not provoke rejection. This involves a comprehensive study of physiological conditions and the anatomy of the body where a biomaterial has to be implemented. The possibility of generating new materials from biominerals has a major impact in medicine and other fields could reach as geology, construction, crystallography, etc. While the study of these issues is in its infancy today, can be viewed as an impact on the art and future technology. Planning case study that students would prepare its report for discussion in subgroups. Occurs then the pooling of individual analysis, joint case discussion and adoption by the subgroup of a consensual solution to the problem. The teacher as facilitator and coordinator of the final case analysis, sharing leads to group-wide class and said the unanimous decision reached by the students and gives his opinion on the resolution of the case. REFERENCES D.P. Ausubel. Psicología Educativa. Un punto de vista cognoscitivo. Trillas. Ed. 1983. E.W. Eisner. Procesos

  17. Biomaterials and tissue engineering in reconstructive surgery

    D F Williams

    2003-06-01

    This paper provides an account of the rationale for the development of implantable medical devices over the last half-century and explains the criteria that have controlled the selection of biomaterials for these critical applications. In spite of some good successes and excellent materials, there are still serious limitations to the performance of implants today, and the paper explains these limitations and develops this theme in order to describe the recent innovations in tissue engineering, which involves a different approach to reconstruction of the body.

  18. Atomic layer deposition of nanoporous biomaterials

    Roger J Narayan

    2010-03-01

    Full Text Available Due to its chemical stability, uniform pore size, and high pore density, nanoporous alumina is being investigated for use in biosensing, drug delivery, hemodialysis, and other medical applications. In recent work, we have examined the use of atomic layer deposition for coating the surfaces of nanoporous alumina membranes. Zinc oxide coatings were deposited on nanoporous alumina membranes using atomic layer deposition. The zinc oxide-coated nanoporous alumina membranes demonstrated antimicrobial activity against Escherichia coli and Staphylococcus aureus bacteria. These results suggest that atomic layer deposition is an attractive technique for modifying the surfaces of nanoporous alumina membranes and other nanostructured biomaterials.

  19. Thermal Characterization of Adhesive

    Spomer, Ken A.

    1999-01-01

    The current Space Shuttle Reusable Solid Rocket Motor (RSRM) nozzle adhesive bond system is being replaced due to obsolescence. Down-selection and performance testing of the structural adhesives resulted in the selection of two candidate replacement adhesives, Resin Technology Group's Tiga 321 and 3M's EC2615XLW. This paper describes rocket motor testing of these two adhesives. Four forty-pound charge motors were fabricated in configurations that would allow side by side comparison testing of the candidate replacement adhesives and the current RSRM adhesives. The motors provided an environment where the thermal performance of adhesives in flame surface bondlines was compared. Results of the FPC testing show that: 1) The phenolic char depths on radial bond lines is approximately the same and vary depending on the position in the blast tube regardless of which adhesive was used; 2) The adhesive char depth of the candidate replacement adhesives is less than the char depth of the current adhesives; 3) The heat-affected depth of the candidate replacement adhesives is less than the heat-affected depth of the current adhesives; and 4) The ablation rates for both replacement adhesives are slower than that of the current adhesives.

  20. Biomaterials for integration with 3-D bioprinting.

    Skardal, Aleksander; Atala, Anthony

    2015-03-01

    Bioprinting has emerged in recent years as an attractive method for creating 3-D tissues and organs in the laboratory, and therefore is a promising technology in a number of regenerative medicine applications. It has the potential to (i) create fully functional replacements for damaged tissues in patients, and (ii) rapidly fabricate small-sized human-based tissue models, or organoids, for diagnostics, pathology modeling, and drug development. A number of bioprinting modalities have been explored, including cellular inkjet printing, extrusion-based technologies, soft lithography, and laser-induced forward transfer. Despite the innovation of each of these technologies, successful implementation of bioprinting relies heavily on integration with compatible biomaterials that are responsible for supporting the cellular components during and after biofabrication, and that are compatible with the bioprinting device requirements. In this review, we will evaluate a variety of biomaterials, such as curable synthetic polymers, synthetic gels, and naturally derived hydrogels. Specifically we will describe how they are integrated with the bioprinting technologies above to generate bioprinted constructs with practical application in medicine. PMID:25476164

  1. Biomaterials and Magnetic fields for Cancer Therapy

    Ramachandran, Narayanan; Mazuruk, Konstanty

    2003-01-01

    The field of biomaterials has emerged as an important topic in the purview of NASA s new vision of research activities in the Microgravity Research Division. Although this area has an extensive track record in the medical field as borne out by the routine use of polymeric sutures, implant devices, and prosthetics, novel applications such as tissue engineering, artificial heart valves and controlled drug delivery are beginning to be developed. Besides the medical field, biomaterials and bio-inspired technologies are finding use in a host of emerging interdisciplinary fields such as self-healing and self-assembling structures, biosensors, fuel systems etc. The field of magnetic fluid technology has several potential applications in medicine. One of the emerging fields is the area of controlled drug delivery, which has seen its evolution from the basic oral delivery system to pulmonary to transdermal to direct inoculations. In cancer treatment by chemotherapy for example, targeted and controlled drug delivery has received vast scrutiny and substantial research and development effort, due to the high potency of the drugs involved and the resulting requirement to keep the exposure of the drugs to surrounding healthy tissue to a minimum. The use of magnetic particles in conjunction with a static magnetic field allows smart targeting and retention of the particles at a desired site within the body with the material transport provided by blood perfusion. Once so located, the therapeutical aspect (radiation, chemotherapy, hyperthermia, etc.) of the treatment, now highly localized, can be implemented.

  2. Surface characterization of collagen/elastin based biomaterials for tissue regeneration

    Skopinska-Wisniewska, J.; Sionkowska, A.; Kaminska, A.; Kaznica, A.; Jachimiak, R.; Drewa, T.

    2009-07-01

    Collagen and elastin are the main proteins of extracellular matrix. Collagen plays a crucial role in tensile strength of tissues, whereas elastin provides resilience to many organs. Both biopolymers are readily available and biocompatible. These properties point out that collagen and elastin are good components of materials for many potential medical applications. The surface properties of biomaterials play an important role in biomedicine as the majority of biological reactions occur on the surface of implanted materials. One of the methods of surface modification is UV-irradiation. The exposition of the biomaterial on ultraviolet light can alterate surface properties of the materials, their chemical stability, swelling properties and mechanical properties as well. The aim of our work was to study the surface properties and biocompatibility of new collagen/elastin based biomaterials and consideration of the influence of ultraviolet light on these properties. The surface properties of collagen/elastin based biomaterials modified by UV-irradiation were studied using the technique of atomic force microscopy (AFM) and contact angle measurements. On the basis of the results the surface free energy and its polar component was calculated using Owens-Wendt method. To assess the biological performance of films based on collagen, elastin and their blends, the response of 3T3 cell was investigated. It was found that the surface of collagen/elastin film is enriched in less polar component - collagen. Exposition on UV light increases polarity of collagen/elastin based films, due to photooxidation process. The AFM images have shown that topography and roughness of the materials had been also affected by UV-irradiation. The changes in surface properties influence on interaction between the material's surface and cells. The investigation of 3T3 cells grown on films based on collagen, elastin and their blends, leads to the conclusion that higher content of elastin in biomaterial

  3. Surface characterization of collagen/elastin based biomaterials for tissue regeneration

    Collagen and elastin are the main proteins of extracellular matrix. Collagen plays a crucial role in tensile strength of tissues, whereas elastin provides resilience to many organs. Both biopolymers are readily available and biocompatible. These properties point out that collagen and elastin are good components of materials for many potential medical applications. The surface properties of biomaterials play an important role in biomedicine as the majority of biological reactions occur on the surface of implanted materials. One of the methods of surface modification is UV-irradiation. The exposition of the biomaterial on ultraviolet light can alterate surface properties of the materials, their chemical stability, swelling properties and mechanical properties as well. The aim of our work was to study the surface properties and biocompatibility of new collagen/elastin based biomaterials and consideration of the influence of ultraviolet light on these properties. The surface properties of collagen/elastin based biomaterials modified by UV-irradiation were studied using the technique of atomic force microscopy (AFM) and contact angle measurements. On the basis of the results the surface free energy and its polar component was calculated using Owens-Wendt method. To assess the biological performance of films based on collagen, elastin and their blends, the response of 3T3 cell was investigated. It was found that the surface of collagen/elastin film is enriched in less polar component - collagen. Exposition on UV light increases polarity of collagen/elastin based films, due to photooxidation process. The AFM images have shown that topography and roughness of the materials had been also affected by UV-irradiation. The changes in surface properties influence on interaction between the material's surface and cells. The investigation of 3T3 cells grown on films based on collagen, elastin and their blends, leads to the conclusion that higher content of elastin in biomaterial

  4. Repairing Femoral Fractures: A Model Lesson in Biomaterial Science

    Sakakeeny, Jarred

    2006-01-01

    Biomaterial science is a rapidly growing field that has scientists and doctors searching for new ways to repair the body. A merger between medicine and engineering, biomaterials can be complex subject matter, and it can certainly capture the minds of middle school students. In the lesson described in this article, seventh graders generally learn…

  5. Innate Immunity and Biomaterials at the Nexus: Friends or Foes

    Susan N. Christo

    2015-01-01

    Full Text Available Biomaterial implants are an established part of medical practice, encompassing a broad range of devices that widely differ in function and structural composition. However, one common property amongst biomaterials is the induction of the foreign body response: an acute sterile inflammatory reaction which overlaps with tissue vascularisation and remodelling and ultimately fibrotic encapsulation of the biomaterial to prevent further interaction with host tissue. Severity and clinical manifestation of the biomaterial-induced foreign body response are different for each biomaterial, with cases of incompatibility often associated with loss of function. However, unravelling the mechanisms that progress to the formation of the fibrotic capsule highlights the tightly intertwined nature of immunological responses to a seemingly noncanonical “antigen.” In this review, we detail the pathways associated with the foreign body response and describe possible mechanisms of immune involvement that can be targeted. We also discuss methods of modulating the immune response by altering the physiochemical surface properties of the biomaterial prior to implantation. Developments in these areas are reliant on reproducible and effective animal models and may allow a “combined” immunomodulatory approach of adapting surface properties of biomaterials, as well as treating key immune pathways to ultimately reduce the negative consequences of biomaterial implantation.

  6. Novel nanostructured biomaterials: implications for coronary stent thrombosis

    Karagkiozaki V

    2012-12-01

    Full Text Available Varvara Karagkiozaki,1,2 Panagiotis G Karagiannidis,1 Nikolaos Kalfagiannis,1 Paraskevi Kavatzikidou,1 Panagiotis Patsalas,3 Despoina Georgiou,1 Stergios Logothetidis11Lab for Thin Films – Nanosystems and Nanometrology (LTFN, Physics Department, Aristotle University of Thessaloniki, Thessaloniki, 2AHEPA Hospital, Aristotle University of Thessaloniki, Thessaloniki, 3Department of Materials Science and Engineering, University of Ioannina, Ioannina, Epirus, GreeceBackground: Nanomedicine has the potential to revolutionize medicine and help clinicians to treat cardiovascular disease through the improvement of stents. Advanced nanomaterials and tools for monitoring cell–material interactions will aid in inhibiting stent thrombosis. Although titanium boron nitride (TiBN, titanium diboride, and carbon nanotube (CNT thin films are emerging materials in the biomaterial field, the effect of their surface properties on platelet adhesion is relatively unexplored.Objective and methods: In this study, novel nanomaterials made of amorphous carbon, CNTs, titanium diboride, and TiBN were grown by vacuum deposition techniques to assess their role as potential stent coatings. Platelet response towards the nanostructured surfaces of the samples was analyzed in line with their physicochemical properties. As the stent skeleton is formed mainly of stainless steel, this material was used as reference material. Platelet adhesion studies were carried out by atomic force microscopy and scanning electron microscopy observations. A cell viability study was performed to assess the cytocompatibility of all thin film groups for 24 hours with a standard immortalized cell line.Results: The nanotopographic features of material surface, stoichiometry, and wetting properties were found to be significant factors in dictating platelet behavior and cell viability. The TiBN films with higher nitrogen contents were less thrombogenic compared with the biased carbon films and control

  7. Platelet responses to dynamic biomaterial surfaces with different poly(ethylene glycol) and polyrotaxane molecular architectures constructed on gold substrates.

    Kakinoki, Sachiro; Yui, Nobuhiko; Yamaoka, Tetsuji

    2013-11-01

    Four different dynamic biomaterial surfaces with different molecular architectures were prepared using two hydrophilic polymers: poly(ethylene glycol) and polyrotaxanes containing α-cyclodextrin. Either one or both terminals of the poly(ethylene glycol) or polyrotaxanes were immobilized onto a gold substrate via Au-S bonds, resulting in poly(ethylene glycol)-graft, polyrotaxanes-graft, poly(ethylene glycol)-loop, and polyrotaxanes-loop structures. Human platelet adhesion was suppressed more effectively on the graft surfaces than on the loop surfaces for both poly(ethylene glycol) and polyrotaxanes due to the high mobility of graft polymer chains with a free terminal. Moreover, the platelets adhered to the polyrotaxane surfaces much less than the poly(ethylene glycol) surfaces, possibly because of the mobile nature of the α-cyclodextrin molecules that were threaded on the poly(ethylene glycol) chain. Actin filament assembly in adherent platelets was also greatly prevented on the poly(ethylene glycol)/polyrotaxanes-graft surfaces in comparison with the corresponding loop surfaces. A clear correlation between the numbers and areas of adherent platelets on these surfaces suggests that platelet adhesion and activation were dominated by the platelet GPIIb/IIIa-adsorbed fibrinogen interaction. These results indicate that both of the different modes of dynamic features, sliding/rotation of α-cyclodextrin and polymer chain mobility, effectively suppressed platelet adhesion in spite of the similar hydrophilicity. This research affords a novel chemical strategy for designing hemocompatible biomaterial surfaces. PMID:23048065

  8. Understanding Marine Mussel Adhesion

    H. G. Silverman; F. F. Roberto

    2007-12-01

    In addition to identifying the proteins that have a role in underwater adhesion by marine mussels, research efforts have focused on identifying the genes responsible for the adhesive proteins, environmental factors that may influence protein production, and strategies for producing natural adhesives similar to the native mussel adhesive proteins. The production-scale availability of recombinant mussel adhesive proteins will enable researchers to formulate adhesives that are waterimpervious and ecologically safe and can bind materials ranging from glass, plastics, metals, and wood to materials, such as bone or teeth, biological organisms, and other chemicals or molecules. Unfortunately, as of yet scientists have been unable to duplicate the processes that marine mussels use to create adhesive structures. This study provides a background on adhesive proteins identified in the blue mussel, Mytilus edulis, and introduces our research interests and discusses the future for continued research related to mussel adhesion.

  9. Understanding marine mussel adhesion.

    Silverman, Heather G; Roberto, Francisco F

    2007-01-01

    In addition to identifying the proteins that have a role in underwater adhesion by marine mussels, research efforts have focused on identifying the genes responsible for the adhesive proteins, environmental factors that may influence protein production, and strategies for producing natural adhesives similar to the native mussel adhesive proteins. The production-scale availability of recombinant mussel adhesive proteins will enable researchers to formulate adhesives that are water-impervious and ecologically safe and can bind materials ranging from glass, plastics, metals, and wood to materials, such as bone or teeth, biological organisms, and other chemicals or molecules. Unfortunately, as of yet scientists have been unable to duplicate the processes that marine mussels use to create adhesive structures. This study provides a background on adhesive proteins identified in the blue mussel, Mytilus edulis, and introduces our research interests and discusses the future for continued research related to mussel adhesion. PMID:17990038

  10. A Review of Cell Adhesion Studies for Biomedical and Biological Applications

    Ahmad Khalili, Amelia; Ahmad, Mohd Ridzuan

    2015-01-01

    Cell adhesion is essential in cell communication and regulation, and is of fundamental importance in the development and maintenance of tissues. The mechanical interactions between a cell and its extracellular matrix (ECM) can influence and control cell behavior and function. The essential function of cell adhesion has created tremendous interests in developing methods for measuring and studying cell adhesion properties. The study of cell adhesion could be categorized into cell adhesion attachment and detachment events. The study of cell adhesion has been widely explored via both events for many important purposes in cellular biology, biomedical, and engineering fields. Cell adhesion attachment and detachment events could be further grouped into the cell population and single cell approach. Various techniques to measure cell adhesion have been applied to many fields of study in order to gain understanding of cell signaling pathways, biomaterial studies for implantable sensors, artificial bone and tooth replacement, the development of tissue-on-a-chip and organ-on-a-chip in tissue engineering, the effects of biochemical treatments and environmental stimuli to the cell adhesion, the potential of drug treatments, cancer metastasis study, and the determination of the adhesion properties of normal and cancerous cells. This review discussed the overview of the available methods to study cell adhesion through attachment and detachment events. PMID:26251901

  11. A hydrophobic perfluoropolyether elastomer as a patternable biomaterial for cell culture and tissue engineering.

    Schulte, Vera A; Hu, Yibing; Diez, Mar; Bünger, Daniel; Möller, Martin; Lensen, Marga C

    2010-11-01

    We present a systematic study of a perfluoropolyether (PFPE)-based elastomer as a new biomaterial. Besides its excellent long-term stability and inertness, PFPE can be decorated with topographical surface structures by replica molding. Micrometer-sized pillar structures led to considerably different cell morphology of fibroblasts. Although PFPE is a very hydrophobic material we could show that PFPE substrates allow cell adhesion and spreading of primary human fibroblasts (HDF) very similar to that observed on standard cell culture substrates. Less advanced cell spreading was observed for L929 (murine fibroblast cell line) cells during the first 5 h in culture which was accompanied by retarded recruitment of α(v)β(3)-integrin into focal adhesions (FAs). After 24 h distinct FAs were evident also in L929 cells on PFPE. Furthermore, organization of soluble FN into a fibrillar ECM network was shown for hdF and L929 cells. Based on these results PFPE is believed to be a suitable substrate for several biological applications. On the one hand it is an ideal cell culture substrate for fundamental research of substrate-independent adhesion signaling due to its different characteristics (e.g. wettability, elasticity) compared to glass or TCPS. On the other hand it could be a promising implant material, especially due to its straightforward patternability, which is a tool to direct cell growth and differentiation. PMID:20708794

  12. Laser surface modification of metallic biomaterials

    Bandyopadhyay, Amit; Balla, Vamsi Krishna; Roy, Mangal; Bose, Susmita

    2011-06-01

    Load-bearing metal implants often fail prematurely due to inadequate biocompatibility, mechanical/tribological properties, and poor osseointegration. It is well known that biomaterials' surface plays a vital role in the response to these metal implants in the biological environment. The biological effectiveness of artificial implants is determined mainly by their surface characteristics such as surface morphology, microstructure, composition, mechanical properties, wettabilility, and surface free energy. Hence, there is significant interest toward surface modification and effective design of load-bearing metal implants so as to improve their surface properties and thereby elicit a specific, desired, and timely response from the surrounding cells and tissues. In this article, we provide an insight into laser surface modification of Ti/Ti6Al4V alloy with or without functional gradation in composition and their microstructural, in vitro wear and biological properties for various loadbearing orthopedic applications.

  13. What future for zirconia as a biomaterial?

    Chevalier, Jérôme

    2006-02-01

    The failure events of Prozyr femoral heads in 2001-2002 have opened a strong, controversial issue on the future of zirconia as a biomaterial. The aim of this paper is to review and analyze the current knowledge on ageing process and on its effect on the long term performance of implants in order to distinguish between scientific facts and speculation. Current state of the art shows the strong variability of zirconia to in vivo degradation, as a consequence of the strong influence of processing on ageing process. As different zirconia from different vendors have different process related microstructure, there is a need to assess their ageing sensitivity with advanced and accurate techniques, and ISO standards should be modified, especially to gain confidence from clinicians. There is a trend today to develop alumina-zirconia composites as an alternative to monolithic alumina and zirconia: the issue of ageing is also discussed for these composites. PMID:16143387

  14. Advanced biomaterials development from "natural products".

    Baier, R E

    1988-04-01

    Natural substances and structures can serve increasingly well as biomedical products, given recent advances in understanding of requirements for biocompatibility and of methods for their preservation and surface tailoring. A successful example is the derivation of limb salvaging vessels, used in arterial reconstructive surgery, from human umbilical cords. There are numerous opportunities for additional product development from the umbilical cords' main ingredient, Wharton's gel, ranging from biolubricants to wound-healing aids. Major problems yet to be overcome with natural starting materials are their propensity for calcification and eventual biodeterioration. Surface modification of biomaterials to exhibit desired degrees of interaction with contacting viable tissues promises the greatest beneficial results. General principles of bioadhesion have broad applicability, predicting material behavior in environments as diverse as blood, saliva, and seawater. PMID:3058928

  15. Chitosan dan Aplikasi Klinisnya Sebagai Biomaterial

    Bambang Irawan

    2015-10-01

    Full Text Available The development of new materials with both organic and inorganic structures is of great interest to obtain special material properties. Chitosan [2-amino-2-deoxy-D-glucan] can be obtained by N-deacetylation of chitin. Chitin is the second most abundant biopolymer in nature and the supporting material of crustaceans, insects, fungi etc. Chitosan is unique polysaccharide and has been widely used in various biomedical application due to its biocompatibility, low toxicity, biodegradability, non-immunogenic and non-carcinogenic character. In the past few years, chitosan and some of its modifications have been reported for use in biomedical applications such as artificial skin, wound dressing, anticoagulant, suture, drug delivery, vaccine carrier and dietary fibers. Recently, the use of chitosan and its derivatives has received much attention as temporary scaffolding to promotie mineralization or stimulate endochodral ossification. This article aims to give a broad overview of chitosan and its clinical applications as biomaterial.

  16. Patterned macroarray plates in comparison of bacterial adhesion inhibition of tantalum, titanium, and chromium compared with diamond-like carbon.

    Levon, Jaakko; Myllymaa, Katja; Kouri, Vesa-Petteri; Rautemaa, Riina; Kinnari, Teemu; Myllymaa, Sami; Konttinen, Yrjö T; Lappalainen, Reijo

    2010-03-15

    Staphylococcus aureus device-related infection is a common complication in implantology. Bacterial adhesion on implant surfaces is the initial step in the infective process. The aim was to develop a method suitable for quantitative bacterial adherence studies and to test a new diamond-like carbon (DLC) coating against commonly used metallic biomaterials with regards to Staphylococcus aureus adhesion. Patterned silicon chips with spots of tantalum, titanium, chromium, and DLC were produced using ultraviolet lithography and physical vapor deposition. These patterned chips were used as such or glued to array plates, pretreated with serum and exposed to S. aureus (S-15981) for 90 min, followed by acridine orange staining and fluorescence microscopy. An adhesion index showed that the ranking order of the biomaterials was titanium, tantalum, chromium, and DLC, with the DLC being clearly most resistant against colonization with S. aureus. Micropatterned surfaces are useful for quantitative comparison of bacterial adherence on different biomaterials. In the presence of serum, DLC is superior in its ability to resist adhesion and colonization by S. aureus compared with the commonly used biomaterial metals tantalum, titanium, and chromium. PMID:19437436

  17. PH dependent adhesive peptides

    Tomich, John; Iwamoto, Takeo; Shen, Xinchun; Sun, Xiuzhi Susan

    2010-06-29

    A novel peptide adhesive motif is described that requires no receptor or cross-links to achieve maximal adhesive strength. Several peptides with different degrees of adhesive strength have been designed and synthesized using solid phase chemistries. All peptides contain a common hydrophobic core sequence flanked by positively or negatively charged amino acids sequences.

  18. Review for carrageenan-based pharmaceutical biomaterials: favourable physical features versus adverse biological effects.

    Liu, Jingjing; Zhan, Xiudan; Wan, Jianbo; Wang, Yitao; Wang, Chunming

    2015-05-01

    Carrageenan (CRG) is a family of natural polysaccharides derived from seaweeds and has widely been used as food additives. In the past decade, owing to its attractive physicochemical properties, CRG has been developed into versatile biomaterials vehicles for drug delivery. Nevertheless, studies also emerged to reveal its adverse effects on the biological system. In this review, we critically appraise the latest literature (two thirds since 2008) on the development of CRG-based pharmaceutical vehicles and the perspective of using CRG for broader biomedical applications. We focus on how current strategies exploit the unique gelling mechanisms, strong water absorption and abundant functional groups of the three major CRG varieties. Notably, CRG-based matrices are demonstrated to increase drug loading and drug solubility, enabling release of orally administrated drugs in zero-order or in a significantly prolonged period. Other amazing features, such as pH-sensitivity and adhesive property, of CRG-based formulations are also introduced. Finally, we discuss the adverse influence of CRG on the human body and then suggest some future directions for the development of CRG-based biomaterials for broader applications in biomedicine. PMID:25659668

  19. Quantification of Staphylococcus aureus adhesion forces on various dental restorative materials using atomic force microscopy

    Merghni, Abderrahmen; Kammoun, Dorra; Hentati, Hajer; Janel, Sébastien; Popoff, Michka; Lafont, Frank; Aouni, Mahjoub; Mastouri, Maha

    2016-08-01

    In the oral cavity dental restorative biomaterials can act as a reservoir for infection with opportunistic Staphylococcus aureus pathogen, which can lead to the occurrence of secondary caries and treatment failures. Our aim was to evaluate the adhesion forces by S. aureus on four dental restorative biomaterials and to correlate this finding to differences in specific surface characteristics. Additionally, the influence of salivary conditioning films in exerted adhesion forces was investigated. The substrate hydrophobicity was measured by goniometer and the surface free energy was calculated using the equilibrium advancing contact angle values of water, formamide, and diiodomethane on the tested surfaces. The surface roughness was determined using atomic force microscope (AFM). Additionally, cell force spectroscopy was achieved to quantify the forces that drive cell-substrate interactions. S. aureus bacterium exerted a considerable adhesion forces on various dental restorative materials, which decreased in the presence of saliva conditioning film. The influence of the surface roughness and free energy in initial adhesion appears to be more important than the effect of hydrophobicity, either in presence or absence of saliva coating. Hence, control of surface properties of dental restorative biomaterials is of crucial importance in preventing the attachment and subsequent the biofilm formation.

  20. Particle adhesion and removal

    Mittal, K L

    2015-01-01

    The book provides a comprehensive and easily accessible reference source covering all important aspects of particle adhesion and removal.  The core objective is to cover both fundamental and applied aspects of particle adhesion and removal with emphasis on recent developments.  Among the topics to be covered include: 1. Fundamentals of surface forces in particle adhesion and removal.2. Mechanisms of particle adhesion and removal.3. Experimental methods (e.g. AFM, SFA,SFM,IFM, etc.) to understand  particle-particle and particle-substrate interactions.4. Mechanics of adhesion of micro- and  n

  1. Combinational Effect of Cell Adhesion Biomolecules and Their Immobilized Polymer Property to Enhance Cell-Selective Adhesion

    Rio Kurimoto

    2016-01-01

    Full Text Available Although surface immobilization of medical devices with bioactive molecules is one of the most widely used strategies to improve biocompatibility, the physicochemical properties of the biomaterials significantly impact the activity of the immobilized molecules. Herein we investigate the combinational effects of cell-selective biomolecules and the hydrophobicity/hydrophilicity of the polymeric substrate on selective adhesion of endothelial cells (ECs, fibroblasts (FBs, and smooth muscle cells (SMCs. To control the polymeric substrate, biomolecules are immobilized on thermoresponsive poly(N-isopropylacrylamide-co-2-carboxyisopropylacrylamide (poly(NIPAAm-co-CIPAAm-grafted glass surfaces. By switching the molecular conformation of the biomolecule-immobilized polymers, the cell-selective adhesion performances are evaluated. In case of RGDS (Arg-Gly-Asp-Ser peptide-immobilized surfaces, all cell types adhere well regardless of the surface hydrophobicity. On the other hand, a tri-Arg-immobilized surface exhibits FB-selectivity when the surface is hydrophilic. Additionally, a tri-Ile-immobilized surface exhibits EC-selective cell adhesion when the surface is hydrophobic. We believe that the proposed concept, which is used to investigate the biomolecule-immobilized surface combination, is important to produce new biomaterials, which are highly demanded for medical implants and tissue engineering.

  2. XPS - an essential tool in biomaterial research

    Full text: Increased life expectancy has markedly enhanced the need for biomedical devices to combat life-threatening conditions (e.g., pacemakers, artificial blood vessels) or improve the quality of life (e.g., intraocular lenses, artificial ligaments, contact lenses). While the biomedical device industry has delivered remarkable benefits, many existing and emerging needs and applications are not adequately met with existing synthetic materials. Depending on the application, a biomaterial needs to meet a number of requirements to be 'biocompatible', such as appropriate mechanical properties, transparency, resistance to enzymatic degradation, and appropriate biological responses by the host environment. Surface science and surface analysis plays a key role in understanding and optimizing the molecular interfacial interactions between synthetic materials surfaces and biological media which lead to biological responses to implants. Many biological molecules such as proteins and lipids have surfactant activity and respond to interfaces on contact. Thus, an important part of achieving 'biocompatibility' is to produce an appropriate surface chemical composition that avoids undesirable biological consequences triggered by biological molecules recognizing a 'foreign' material interface. XPS surface analysis has proved uniquely suitable for studying several aspects of biomaterials. In order to interpret biological responses in terms of surface chemistry, it is essential that the surface be well characterized. However, for polymers this can be quite a challenge due to the inherent mobility of polymer chains. For instance, polyurethanes present a surface chemistry that differs from the 'bulk' chemistry. It is often desirable to utilize a bulk material with desirable bulk properties and improve its biocompatibility by the application of a surface modification or a thin coating. XPS has been used to verify the intended coating chemistry and the uniformity of thin coatings. On

  3. Brillouin microspectroscopy of nanostructured biomaterials: photonics assisted tailoring mechanical properties

    Meng, Zhaokai; Jaiswal, Manish K.; Chitrakar, Chandani; Thakur, Teena; Gaharwar, Akhilesh K.; Yakovlev, Vladislav V.

    2016-03-01

    Developing new biomaterials is essential for the next-generation of materials for bioenergy, bioelectronics, basic biology, medical diagnostics, cancer research, and regenerative medicine. Specifically, recent progress in nanotechnology has stimulated the development of multifunctional biomaterials for tissue engineering applications. The physical properties of nanocomposite biomaterials, including elasticity and viscosity, play key roles in controlling cell fate, which underlines therapeutic success. Conventional mechanical tests, including uniaxial compression and tension, dynamic mechanical analysis and shear rheology, require mechanical forces to be directly exerted onto the sample and therefore may not be suitable for in situ measurements or continuous monitoring of mechanical stiffness. In this study, we employ spontaneous Brillouin spectroscopy as a viscoelasticity-specific probing technique. We utilized a Brillouin spectrometer to characterize biomaterial's microscopic elasticity and correlated those with conventional mechanical tests (e.g., rheology).

  4. Engineering Immunomodulatory Biomaterials To Tune the Inflammatory Response.

    Vishwakarma, Ajaykumar; Bhise, Nupura S; Evangelista, Marta B; Rouwkema, Jeroen; Dokmeci, Mehmet R; Ghaemmaghami, Amir M; Vrana, Nihal Engin; Khademhosseini, Ali

    2016-06-01

    Current state-of-the-art biomedical implants and tissue engineering methods promise technologies to improve or even restore the function of diseased organs. However, one of the biggest challenges to clinical success is the lack of functional integration. A series of cellular and molecular events following biomaterial implantation poses an important bottleneck for developing breakthrough solutions. With inflammation increasingly recognized as a crucial component influencing regeneration, immunomodulation or immuno-engineering has emerged as a potential solution to overcome this key challenge in regenerative medicine. We postulate possibilities to utilize biomaterial physicochemical modifications to modulate the host inflammatory response and develop strategies for effective biomaterial integration. Biomaterial-based immunomodulation strategies can significantly ameliorate the outcomes of medical implants and tissue engineering therapies. PMID:27138899

  5. Design of polymer-biopolymer-hydroxyapatite biomaterials for bone tissue engineering: Through molecular control of interfaces

    Verma, Devendra

    -containing scaffolds. Hydroxyapatite-containing chitosan/PgA scaffolds maintained their structural integrity under wet conditions. These scaffolds showed extremely porous (97.4%) and interconnected architecture. These scaffolds also promoted cell adhesion, proliferation and differentiation, Osteoblast cells formed nodular structure on thin films and scaffold. Mineralization of these nodules was confirmed by alizarin red S staining. Even after 20 days of seeding, all the cells were found alive. Our results indicated that chitosan-PgA-hydroxyapatite composite scaffolds have high potential for bone tissue engineering. This dissertation represents a comprehensive study on design of novel bone biomaterials through tailoring of interfaces in nanocomposites of polymers, biopolymer and hydroxyapatite.

  6. Numerical Simulation of thePorous Structure of Biomaterials

    WANGHui-min; YANYu-hua; LIShi-pu

    2004-01-01

    Porous biomaterials are widely used as bone replacement materials because of thers high biocompatibility and osteoconductivity property. Understanding of their porous structure (i. e. geometrical and topological characteristic) and studying how to the body fluid flow through them are essential to investigate thed egradation behaviour at the surface-liquid interface. This research develops a numerical model to simulate the porous structure of biomaterials based on the stochastic approach in pore size distribution and interconnectivity.

  7. A Multidisciplined Teaching Reform of Biomaterials Course for Undergraduate Students

    Li, Xiaoming; Zhao, Feng; Pu, Fang; Liu, Haifeng; Niu, Xufeng; Zhou, Gang; Li, Deyu; Fan, Yubo; Feng, Qingling; Cui, Fu-zhai; Watari, Fumio

    2015-12-01

    The biomaterials science has advanced in a high speed with global science and technology development during the recent decades, which experts predict to be more obvious in the near future with a more significant position for medicine and health care. Although the three traditional subjects, such as medical science, materials science and biology that act as a scaffold to support the structure of biomaterials science, are still essential for the research and education of biomaterials, other subjects, such as mechanical engineering, mechanics, computer science, automatic science, nanotechnology, and Bio-MEMS, are playing more and more important roles in the modern biomaterials science development. Thus, the research and education of modern biomaterials science should require a logical integration of the interdisciplinary science and technology, which not only concerns medical science, materials science and biology, but also includes other subjects that have been stated above. This article focuses on multidisciplinary nature of biomaterials, the awareness of which is currently lacking in the education at undergraduate stage. In order to meet this educational challenge, we presented a multidisciplinary course that referred to not only traditional sciences, but also frontier sciences and lasted for a whole academic year for senior biomaterials undergraduate students with principles of a better understanding of the modern biomaterials science and meeting the requirements of the future development in this area. The course has been shown to gain the recognition of the participants by questionaries and specific "before and after" comments and has also gained high recognition and persistent supports from our university. The idea of this course might be also fit for the education and construction of some other disciplines.

  8. Characterization of Biomaterials by Soft X-Ray Spectromicroscopy

    Hitchcock, Adam P.; Leung, Bonnie O.; Brash, John L.

    2010-01-01

    Synchrotron-based soft X-ray spectromicroscopy techniques are emerging as useful tools to characterize potentially biocompatible materials and to probe protein interactions with model biomaterial surfaces. Simultaneous quantitative chemical analysis of the near surface region of the candidate biomaterial, and adsorbed proteins, peptides or other biological species can be obtained at high spatial resolution via scanning transmission X-ray microscopy (STXM) and X-ray photoemission electron micr...

  9. Advancing the field of 3D biomaterial printing.

    Jakus, Adam E; Rutz, Alexandra L; Shah, Ramille N

    2016-02-01

    3D biomaterial printing has emerged as a potentially revolutionary technology, promising to transform both research and medical therapeutics. Although there has been recent progress in the field, on-demand fabrication of functional and transplantable tissues and organs is still a distant reality. To advance to this point, there are two major technical challenges that must be overcome. The first is expanding upon the limited variety of available 3D printable biomaterials (biomaterial inks), which currently do not adequately represent the physical, chemical, and biological complexity and diversity of tissues and organs within the human body. Newly developed biomaterial inks and the resulting 3D printed constructs must meet numerous interdependent requirements, including those that lead to optimal printing, structural, and biological outcomes. The second challenge is developing and implementing comprehensive biomaterial ink and printed structure characterization combined with in vitro and in vivo tissue- and organ-specific evaluation. This perspective outlines considerations for addressing these technical hurdles that, once overcome, will facilitate rapid advancement of 3D biomaterial printing as an indispensable tool for both investigating complex tissue and organ morphogenesis and for developing functional devices for a variety of diagnostic and regenerative medicine applications. PMID:26752507

  10. Biomaterial Applications in Cell-Based Therapy in Experimental Stroke

    Boisserand, Ligia S. B.; Kodama, Tomonobu; Papassin, Jérémie; Auzely, Rachel; Moisan, Anaïck; Rome, Claire; Detante, Olivier

    2016-01-01

    Stroke is an important health issue corresponding to the second cause of mortality and first cause of severe disability with no effective treatments after the first hours of onset. Regenerative approaches such as cell therapy provide an increase in endogenous brain structural plasticity but they are not enough to promote a complete recovery. Tissue engineering has recently aroused a major interesting development of biomaterials for use into the central nervous system. Many biomaterials have been engineered based on natural compounds, synthetic compounds, or a mix of both with the aim of providing polymers with specific properties. The mechanical properties of biomaterials can be exquisitely regulated forming polymers with different stiffness, modifiable physical state that polymerizes in situ, or small particles encapsulating cells or growth factors. The choice of biomaterial compounds should be adapted for the different applications, structure target, and delay of administration. Biocompatibilities with embedded cells and with the host tissue and biodegradation rate must be considerate. In this paper, we review the different applications of biomaterials combined with cell therapy in ischemic stroke and we explore specific features such as choice of biomaterial compounds and physical and mechanical properties concerning the recent studies in experimental stroke.

  11. Atomic layer deposition of nanoporous biomaterials.

    Narayan, R. J.; Adiga, S. P.; Pellin, M. J.; Curtiss, L. A.; Stafslien, S.; Chisholm, B.; Monteiro-Riviere, N. A.; Brigmon, R. L.; Elam, J. W.; Univ. of North Carolina; North Carolina State Univ.; Eastman Kodak Co.; North Dakota State Univ.; SRL

    2010-03-01

    Due to its chemical stability, uniform pore size, and high pore density, nanoporous alumina is being investigated for use in biosensing, drug delivery, hemodialysis, and other medical applications. In recent work, we have examined the use of atomic layer deposition for coating the surfaces of nanoporous alumina membranes. Zinc oxide coatings were deposited on nanoporous alumina membranes using atomic layer deposition. The zinc oxide-coated nanoporous alumina membranes demonstrated antimicrobial activity against Escherichia coli and Staphylococcus aureus bacteria. These results suggest that atomic layer deposition is an attractive technique for modifying the surfaces of nanoporous alumina membranes and other nanostructured biomaterials. Nanoporous alumina, also known as anodic aluminum oxide (AAO), is a nanomaterial that exhibits several unusual properties, including high pore densities, straight pores, small pore sizes, and uniform pore sizes. In 1953, Keller et al. showed that anodizing aluminum in acid electrolytes results in a thick layer of nearly cylindrical pores, which are arranged in a close-packed hexagonal cell structure. More recently, Matsuda & Fukuda demonstrated preparation of highly ordered platinum and gold nanohole arrays using a replication process. In this study, a negative structure of nanoporous alumina was initially fabricated and a positive structure of a nanoporous metal was subsequently fabricated. Over the past fifteen years, nanoporous alumina membranes have been used as templates for growth of a variety of nanostructured materials, including nanotubes, nanowires, nanorods, and nanoporous membranes.

  12. Biomaterials for mRNA Delivery

    Islam, Mohammad Ariful; Reesor, Emma K. G.; Xu, Yingjie; Zope, Harshal R.; Zetter, Bruce R.; Shi, Jinjun

    2015-01-01

    Messenger RNA (mRNA) has recently emerged with remarkable potential as an effective alternative to DNA-based therapies because of several unique advantages. mRNA does not require nuclear entry for transfection activity and has a negligible chance of integrating into the host genome which excludes the possibility of potentially detrimental genomic alternations. Chemical modification of mRNA has further enhanced its stability and decreased its activation of innate immune responses. Additionally, mRNA has been found to have rapid expression and predictable kinetics. Nevertheless, the ubiquitous application of mRNA remains challenging given its unfavorable attributes, such as large size, negative charge and susceptibility to enzymatic degradation. Further refinement of mRNA delivery modalities is therefore essential for its development as a therapeutic tool. This review provides an exclusive overview of current state-of-the-art biomaterials and nanotechnology platforms for mRNA delivery, and discusses future prospects to bring these exciting technologies into clinical practice. PMID:26280625

  13. Useful surface parameters for biomaterial discrimination.

    Etxeberria, Marina; Escuin, Tomas; Vinas, Miquel; Ascaso, Carlos

    2015-01-01

    Topographical features of biomaterials' surfaces are determinant when addressing their application site. Unfortunately up to date there has not been an agreement regarding which surface parameters are more representative in discriminating between materials. Discs (n = 16) of different currently used materials for implant prostheses fabrication, such as cast cobalt-chrome, direct laser metal soldered (DLMS) cobalt-chrome, titanium grade V, zirconia (Y-TZP), E-glass fiber-reinforced composite and polyetheretherketone (PEEK) were manufactured. Nanoscale topographical surface roughness parameters generated by atomic force microscopy (AFM), microscale surface roughness parameters obtained by white light interferometry (WLI) and water angle values obtained by the sessile-water-drop method were analyzed in order to assess which parameter provides the best optimum surface characterization method. Correlations between nanoroughness, microroughness, and hydrophobicity data were performed to achieve the best parameters giving the highest discriminatory power. A subset of six parameters for surface characterization were proposed. AFM and WLI techniques gave complementary information. Wettability did not correlate with any of the nanoroughness parameters while it however showed a weak correlation with microroughness parameters. PMID:26148576

  14. Radiation-curable adhesives

    Radiation-curable adhesives may be classified into two broad categories. In the first category, adhesive bonding occurs as a direct result of irradiation. The second category includes pressure-sensitive and hot-melt adhesives, which are composed of linear or lightly cross-linked polymers prepared by a radiation-induced polymerization reaction. This chapter is mainly concerned with radiation-curable adhesives of the first category. The various adhesive types are discussed and adhesive performance is examined, particularly in relation to the chemistry and chemical technology which underlies the individual materials. A description of a limited number of representative applications is included as is an outline of recent developments of curing and dispensing equipment. 268 refs., 14 figs., 13 tabs

  15. Inhibition of postsurgical adhesions by methylene blue-loaded nanofibers versus cast film matrices.

    El-Sayed, Nesma; Galal, Sally; El-Gowelli, Hanan; El-Khordagui, Labiba

    2016-07-01

    In the quest for barrier membranes for the prevention of post-surgical tissue adhesions, polymer matrices may provide a platform of biomaterials with versatile properties. However, the relationship between the anti-adhesion effects of different polymer matrices and their physicochemical and structural properties is not yet adequately understood. In a preclinical study using a rat cecum model, we directly compared the anti-adhesion potential of polyhydroxybutyrate (PHB) electrospun nanofibrous versus cast film matrices loaded with methylene blue (MB) as antioxidant adhesion inhibitor. PHB retained MB presumably forming MB-bioactivated matrices. In the preclinical study, quantitative morphologic assessment in addition to histopathologic and SEM examinations 14 days post-surgery indicated that plain PHB NFs and MB-PHB NFs, moderately enhanced cecal wall healing and inhibited adhesion formation. In contrast, reshaping PHB as cast films, significantly enhanced healing, reduced adhesion bands and prevented inter-visceral adhesions. Cast films also inhibited tissue attachment to the matrix recovered 14 days post-surgery. Both PHB matrix types reduced tissue inflammation. Despite tissue anti-adhesion potential of individual matrix components, modulation of the micro-architectural properties generated polymer barriers with varying tissue anti-adhesion and healing potentials, the MB-loaded cast film achieving the best outcome. PMID:27093975

  16. Prevention of bacterial adhesion

    Klemm, Per; Vejborg, Rebecca Munk; Hancock, Viktoria

    2010-01-01

    Management of bacterial infections is becoming increasingly difficult due to the emergence and increasing prevalence of bacterial pathogens that are resistant to available antibiotics. Conventional antibiotics generally kill bacteria by interfering with vital cellular functions, an approach that....... As such, adhesion represents the Achilles heel of crucial pathogenic functions. It follows that interference with adhesion can reduce bacterial virulence. Here, we illustrate this important topic with examples of techniques being developed that can inhibit bacterial adhesion. Some of these will...

  17. Preparing polymeric biomaterials using "click" chemistry techniques

    Lin, Fei

    Significant efforts have been focused on preparing degradable polymeric biomaterials with controllable properties, which have the potential to stimulate specific cellular responses at the molecular level. Click reactions provide a universal tool box to achieve that goal through molecular level design and modification. This dissertation demonstrates multiple methodologies and techniques to develop advanced biomaterials through combining degradable polymers and click chemistry. In my initial work, a novel class of amino acid-based poly(ester urea)s (PEU) materials was designed and prepared for potential applications in bone defect treatment. PEUs were synthesized via interfacial polycondensation, and showed degradability in vivo and possessed mechanical strength superior to conventionally used polyesters. Further mechanical enhancement was achieved after covalent crosslinking with a short peptide crosslinker derived from osteogenic growth peptide (OGP). The in vitro and in an in vivo subcutaneous rat model demonstrated that the OGP-based crosslinkers promoted proliferative activity of cells and accelerated degradation properties of PEUs. As a continuous study, extra efforts were focused on the development of PEUs with functional pendant groups, including alkyne, azide, alkene, tyrosine phenol, and ketone groups. PEUs with Mw exceeding to 100K Da were obtained via interfacial polycondensation, and the concentration of pendent groups was varied using a copolymerization strategy. Electrospinning was used to fabricate PEU nanofiber matrices with mechanical strengths suitable for tissue engineering. A series of biomolecules were conjugated to nanofiber surface following electrospinning using click reactions in aqueous media. The ability to derivatize PEUs with biological motifs using high efficient chemical reactions will significantly expand their use in vitro and in vivo. Based on similar principles, a series of mono- and multifunctionalized polycaprolactone (PCL

  18. 3'-Hydroxy-4-methoxychalcone as a potential antibacterial coating on polymeric biomaterials

    Antimicrobial property of chalcone coated high density polyethylene (HDPE), low density polyethylene (LDPE), polypropylene (PP) and polyurethane (PU) against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa is reported here. The presence of chalcone on the surface was confirmed from fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Bacterial adhesion decreased considerably on all the coated surfaces. Bacterial adhesion was highest on PU surface (most hydrophobic) and lowest on HDPE (most hydrophilic) surface. Chalcone seems to damage the membrane of the bacteria as well as exhibit slimicidal activity. Reasonably good correlation was observed between the CFU (Colony Forming Units) ratio (it is defined as the ratio of CFU on coated surface to the chalcone uncoated surface) at the 24th hour against both hydrophobicity of the microorganism and roughness of the coated polymeric surfaces. Increasing roughness of the polymer and hydrophobicity of the microorganisms were positively and negatively correlated respectively with CFU ratio. Hence, the chalcone coated polymers can be used in the development of newer biomaterials.

  19. Antibacterial Efficacy of Iron-Oxide Nanoparticles against Biofilms on Different Biomaterial Surfaces

    Monica Thukkaram

    2014-01-01

    Full Text Available Biofilm growth on the implant surface is the number one cause of the failure of the implants. Biofilms on implant surfaces are hard to eliminate by antibiotics due to the protection offered by the exopolymeric substances that embed the organisms in a matrix, impenetrable for most antibiotics and immune cells. Application of metals in nanoscale is considered to resolve biofilm formation. Here we studied the effect of iron-oxide nanoparticles over biofilm formation on different biomaterial surfaces and pluronic coated surfaces. Bacterial adhesion for 30 min showed significant reduction in bacterial adhesion on pluronic coated surfaces compared to other surfaces. Subsequently, bacteria were allowed to grow for 24 h in the presence of different concentrations of iron-oxide nanoparticles. A significant reduction in biofilm growth was observed in the presence of the highest concentration of iron-oxide nanoparticles on pluronic coated surfaces compared to other surfaces. Therefore, combination of polymer brush coating and iron-oxide nanoparticles could show a significant reduction in biofilm formation.

  20. 3'-Hydroxy-4-methoxychalcone as a potential antibacterial coating on polymeric biomaterials

    Sivakumar, P.M., E-mail: sivamedchem@gmail.com [Department of Biotechnology, Indian Institute of Technology Madras, Adyar, Chennai 600036 (India); Iyer, Geetha, E-mail: geethu.v.iyer@gmail.com [Department of Biotechnology, Indian Institute of Technology Madras, Adyar, Chennai 600036 (India); Natesan, Lavanya [Department of Biotechnology, Indian Institute of Technology Madras, Adyar, Chennai 600036 (India); Doble, Mukesh, E-mail: mukeshd@iitm.ac.in [Department of Biotechnology, Indian Institute of Technology Madras, Adyar, Chennai 600036 (India)

    2010-08-01

    Antimicrobial property of chalcone coated high density polyethylene (HDPE), low density polyethylene (LDPE), polypropylene (PP) and polyurethane (PU) against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa is reported here. The presence of chalcone on the surface was confirmed from fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Bacterial adhesion decreased considerably on all the coated surfaces. Bacterial adhesion was highest on PU surface (most hydrophobic) and lowest on HDPE (most hydrophilic) surface. Chalcone seems to damage the membrane of the bacteria as well as exhibit slimicidal activity. Reasonably good correlation was observed between the CFU (Colony Forming Units) ratio (it is defined as the ratio of CFU on coated surface to the chalcone uncoated surface) at the 24th hour against both hydrophobicity of the microorganism and roughness of the coated polymeric surfaces. Increasing roughness of the polymer and hydrophobicity of the microorganisms were positively and negatively correlated respectively with CFU ratio. Hence, the chalcone coated polymers can be used in the development of newer biomaterials.

  1. 3‧-Hydroxy-4-methoxychalcone as a potential antibacterial coating on polymeric biomaterials

    Sivakumar, P. M.; Iyer, Geetha; Natesan, Lavanya; Doble, Mukesh

    2010-08-01

    Antimicrobial property of chalcone coated high density polyethylene (HDPE), low density polyethylene (LDPE), polypropylene (PP) and polyurethane (PU) against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa is reported here. The presence of chalcone on the surface was confirmed from fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Bacterial adhesion decreased considerably on all the coated surfaces. Bacterial adhesion was highest on PU surface (most hydrophobic) and lowest on HDPE (most hydrophilic) surface. Chalcone seems to damage the membrane of the bacteria as well as exhibit slimicidal activity. Reasonably good correlation was observed between the CFU (Colony Forming Units) ratio (it is defined as the ratio of CFU on coated surface to the chalcone uncoated surface) at the 24th hour against both hydrophobicity of the microorganism and roughness of the coated polymeric surfaces. Increasing roughness of the polymer and hydrophobicity of the microorganisms were positively and negatively correlated respectively with CFU ratio. Hence, the chalcone coated polymers can be used in the development of newer biomaterials.

  2. Proteins at the Biomaterial Electrolyte Interface

    Tengvall, Pentti

    2005-03-01

    Proteins adsorb rapidly onto solid and polymeric surfaces because the association process is in the vast majority of cases energetically favourable, i.e. exothermic. The most common exceptions to this rule are hydrophilic interfaces with low net charge and high mobility, e.g. immobilized PEGs. Current research in the research area tries to understand and control unwanted and wanted adsorption by studying the adsorption kinetics, protein surface binding specificity, protein exchange at interfaces, and surface protein repulsion mechanisms. In blood plasma model systems humoral cascade reactions such as surface mediated coagulation and immune complement raise considerable interest due to the immediate association to blood compatibility, and in tissue applications the binding between surfaces and membrane receptors in cells and tissues. Thus, the understanding of interfacial events at the protein level is of large importance in applications such as blood and tissue contacting biomaterials, in vitro medical and biological diagnostics, food industry and in marine anti-fouling technology. Well described consequences of adsorption are a lowered system energy, increased system entropy, irreversible binding, conformational changes, specific surface/protein interactions, and in biomedical materials applications surface opsonization followed by cell-surface interactions and a host tissue response. This lecture will deal with some mechanisms known to be of importance for the adsorption processes, such as the influence of surface chemistry and surface energy, the composition of the protein solution, the Vroman effect, and residence time. Examples will be shown from ellipsometric experiments using different model surfaces in single/few protein solutions, and specific attention be given to blood serum and plasma experiments on coagulation and immune complement at interfaces.

  3. Nanofibers and nanoparticles from the insect-capturing adhesive of the Sundew (Drosera) for cell attachment

    Zhang Mingjun; Lenaghan Scott C; Xia Lijin; Dong Lixin; He Wei; Henson William R; Fan Xudong

    2010-01-01

    Abstract Background The search for naturally occurring nanocomposites with diverse properties for tissue engineering has been a major interest for biomaterial research. In this study, we investigated a nanofiber and nanoparticle based nanocomposite secreted from an insect-capturing plant, the Sundew, for cell attachment. The adhesive nanocomposite has demonstrated high biocompatibility and is ready to be used with minimal preparation. Results Atomic force microscopy (AFM) conducted on the adh...

  4. Substrate effect modulates adhesion and proliferation of fibroblast on graphene layer.

    Lin, Feng; Du, Feng; Huang, Jianyong; Chau, Alicia; Zhou, Yongsheng; Duan, Huiling; Wang, Jianxiang; Xiong, Chunyang

    2016-10-01

    Graphene is an emerging candidate for biomedical applications, including biosensor, drug delivery and scaffold biomaterials. Cellular functions and behaviors on different graphene-coated substrates, however, still remain elusive to a great extent. This paper explored the functional responses of cells such as adhesion and proliferation, to different kinds of substrates including coverslips, silicone, polydimethylsiloxane (PDMS) with different curing ratios, PDMS treated with oxygen plasma, and their counterparts coated with single layer graphene (SLG). Specifically, adherent cell number, spreading area and cytoskeleton configuration were exploited to characterize cell-substrate adhesion ability, while MTT assay was employed to test the proliferation capability of fibroblasts. Experimental outcome demonstrated graphene coating had excellent cytocompatibility, which could lead to an increase in early adhesion, spreading, proliferation, and remodeling of cytoskeletons of fibroblast cells. Notably, it was found that the underlying substrate effect, e.g., stiffness of substrate materials, could essentially regulate the adhesion and proliferation of cells cultured on graphene. The stiffer the substrates were, the stronger the abilities of adhesion and proliferation of fibroblasts were. This study not only deepens our understanding of substrate-modulated interfacial interactions between live cells and graphene, but also provides a valuable guidance for the design and application of graphene-based biomaterials in biomedical engineering. PMID:27451366

  5. Characterization of Biomaterials by Soft X-Ray Spectromicroscopy

    Adam P. Hitchcock

    2010-07-01

    Full Text Available Synchrotron-based soft X-ray spectromicroscopy techniques are emerging as useful tools to characterize potentially biocompatible materials and to probe protein interactions with model biomaterial surfaces. Simultaneous quantitative chemical analysis of the near surface region of the candidate biomaterial, and adsorbed proteins, peptides or other biological species can be obtained at high spatial resolution via scanning transmission X-ray microscopy (STXM and X-ray photoemission electron microscopy (X-PEEM. Both techniques use near-edge X-ray absorption fine structure (NEXAFS spectral contrast for chemical identification and quantitation. The capabilities of STXM and X-PEEM for the analysis of biomaterials are reviewed and illustrated by three recent studies: (1 characterization of hydrophobic surfaces, including adsorption of fibrinogen (Fg or human serum albumin (HSA to hydrophobic polymeric thin films, (2 studies of HSA adsorption to biodegradable or potentially biocompatible polymers, and (3 studies of biomaterials under fully hydrated conditions. Other recent applications of STXM and X-PEEM to biomaterials are also reviewed.

  6. Injectable biomaterials for minimally invasive orthopedic treatments.

    Jayabalan, M; Shalumon, K T; Mitha, M K

    2009-06-01

    Biodegradable and injectable hydroxy terminated-poly propylene fumarate (HT-PPF) bone cement was developed. The injectable formulation consisting HT-PPF and comonomer, n-vinyl pyrrolidone, calcium phosphate filler, free radical catalyst, accelerator and radiopaque agent sets rapidly to hard mass with low exothermic temperature. The candidate bone cement attains mechanical strength more than the required compressive strength of 5 MPa and compressive modulus 50 MPa. The candidate bone cement resin elicits cell adhesion and cytoplasmic spreading of osteoblast cells. The cured bone cement does not induce intracutaneous irritation and skin sensitization. The candidate bone cement is tissue compatible without eliciting any adverse tissue reactions. The candidate bone cement is osteoconductive and inductive and allow osteointegration and bone remodeling. HT-PPF bone cement is candidate bone cement for minimally invasive radiological procedures for the treatment of bone diseases and spinal compression fractures. PMID:19160023

  7. Tissue adhesives in otorhinolaryngology

    Schneider, Gerlind

    2009-01-01

    Full Text Available The development of medical tissue adhesives has a long history without finding an all-purpose tissue adhesive for clinical daily routine. This is caused by the specific demands which are made on a tissue adhesive, and the different areas of application. In otorhinolaryngology, on the one hand, this is the mucosal environment as well as the application on bones, cartilage and periphery nerves. On the other hand, there are stressed regions (skin, oral cavity, pharynx, oesophagus, trachea and unstressed regions (middle ear, nose and paranasal sinuses, cranial bones. But due to the facts that adhesives can have considerable advantages in assuring surgery results, prevention of complications and so reduction of medical costs/treatment expenses, the search for new adhesives for use in otorhinolaryngology will be continued intensively. In parallel, appropriate application systems have to be developed for microscopic and endoscopic use.

  8. Biomaterial systems for orthopedic tissue engineering

    Spoerke, Erik David

    2003-06-01

    The World Health Organization has estimated that one out of seven Americans suffers from a musculoskeletal impairment, annually incurring 28.6 million musculoskeletal injuries---more than half of all injuries. Bone tissue engineering has evolved rapidly to address this continued health concern. In the last decade, the focus of orthopedic biomaterials design has shifted from the use of common engineering metals and plastics to smart materials designed to mimic nature and elicit favorable bioresponse. Working within this new paradigm, this thesis explores unique chemical and materials systems for orthopedic tissue engineering. Improving on current titanium implant technologies, porous titanium scaffolds were utilized to better approximate the mechanical and structural properties of natural bone. These foam scaffolds were enhanced with bioactive coatings, designed to enhance osteoblastic implant colonization. The biopolymer poly(L-lysine) was incorporated into both hydroxypatite and octacalcium phosphate mineral phases to create modified organoapatite and pLys-CP coatings respectively. These coatings were synthesized and characterized on titanium surfaces, including porous structures such as titanium mesh and titanium foam. In addition, in vitro osteoblastic cell culture experiments probed the biological influences of these coatings. Organoapatite (OA) accelerated preosteoblastic colonization of titanium mesh and improved cellular ingrowth into titanium foam. Alternatively, the thin, uniform pLys-CP coating demonstrated significant potential as a substrate for chemically binding biological molecules and supramolecular assemblies. Biologically, pLys-CP demonstrated enhanced cellular attachment over titanium and inorganic calcium phosphate controls. Supramolecular self-assembled nanofiber assemblies were also explored both as stand-alone tissue engineering gels and as titanium coatings. Self-supporting nanofiber gels induced accelerated, biomimetic mineralization

  9. Biomaterials mediated microRNA delivery for bone tissue engineering.

    Sriram, M; Sainitya, R; Kalyanaraman, V; Dhivya, S; Selvamurugan, N

    2015-03-01

    Bone tissue engineering is an alternative strategy to overcome the problems associated with traditional treatments for bone defects. A number of bioactive materials along with new techniques like porous scaffold implantation, gene delivery, 3D organ printing are now-a-days emerging for traditional bone grafts and metal implants. Studying the molecular mechanisms through which these biomaterials induce osteogenesis is an equally hot field. Biomaterials could determine the fate of a cell via microRNAs (miRNAs). miRNAs are short non-coding RNAs that act as post-transcriptional regulators of gene expression and play an essential role for regulation of cell specific lineages including osteogenesis. Thus, this review focuses the recent trends on establishing a link of biomaterials with miRNAs and their delivery for bone tissue engineering applications. PMID:25543062

  10. Biomaterial based cardiac tissue engineering and its applications.

    Huyer, Locke Davenport; Montgomery, Miles; Zhao, Yimu; Xiao, Yun; Conant, Genevieve; Korolj, Anastasia; Radisic, Milica

    2015-06-01

    Cardiovascular disease is a leading cause of death worldwide, necessitating the development of effective treatment strategies. A myocardial infarction involves the blockage of a coronary artery leading to depletion of nutrient and oxygen supply to cardiomyocytes and massive cell death in a region of the myocardium. Cardiac tissue engineering is the growth of functional cardiac tissue in vitro on biomaterial scaffolds for regenerative medicine application. This strategy relies on the optimization of the complex relationship between cell networks and biomaterial properties. In this review, we discuss important biomaterial properties for cardiac tissue engineering applications, such as elasticity, degradation, and induced host response, and their relationship to engineered cardiac cell environments. With these properties in mind, we also emphasize in vitro use of cardiac tissues for high-throughput drug screening and disease modelling. PMID:25989939

  11. Solvent-free functionalization of silicone rubber and efficacy of PAAm brushes grafted from an amino-PPX layer against bacterial adhesion

    Fundeanu, Irina; Klee, Doris; Schouten, Arend J.; Busscher, Henk J.; van der Mei, Henny C.

    2010-01-01

    Silicone rubber is a frequently employed biomaterial that is prone to bacterial adhesion and biofilm formation. In this study, the surface of silicone rubber was solvent-free functionalized by chemical vapor deposition (CVD) of poly(o-amino-p-xylylene-co-p-xylylene (amino-PPX). Subsequently, the ami

  12. Nanofibers and nanoparticles from the insect-capturing adhesive of the Sundew (Drosera for cell attachment

    Zhang Mingjun

    2010-08-01

    Full Text Available Abstract Background The search for naturally occurring nanocomposites with diverse properties for tissue engineering has been a major interest for biomaterial research. In this study, we investigated a nanofiber and nanoparticle based nanocomposite secreted from an insect-capturing plant, the Sundew, for cell attachment. The adhesive nanocomposite has demonstrated high biocompatibility and is ready to be used with minimal preparation. Results Atomic force microscopy (AFM conducted on the adhesive from three species of Sundew found that a network of nanofibers and nanoparticles with various sizes existed independent of the coated surface. AFM and light microscopy confirmed that the pattern of nanofibers corresponded to Alcian Blue staining for polysaccharide. Transmission electron microscopy identified a low abundance of nanoparticles in different pattern form AFM observations. In addition, energy-dispersive X-ray spectroscopy revealed the presence of Ca, Mg, and Cl, common components of biological salts. Study of the material properties of the adhesive yielded high viscoelasticity from the liquid adhesive, with reduced elasticity observed in the dried adhesive. The ability of PC12 neuron-like cells to attach and grow on the network of nanofibers created from the dried adhesive demonstrated the potential of this network to be used in tissue engineering, and other biomedical applications. Conclusions This discovery demonstrates how a naturally occurring nanofiber and nanoparticle based nanocomposite from the adhesive of Sundew can be used for tissue engineering, and opens the possibility for further examination of natural plant adhesives for biomedical applications.

  13. Designed biomaterials to mimic the mechanical properties of muscles.

    Lv, Shanshan; Dudek, Daniel M; Cao, Yi; Balamurali, M M; Gosline, John; Li, Hongbin

    2010-05-01

    The passive elasticity of muscle is largely governed by the I-band part of the giant muscle protein titin, a complex molecular spring composed of a series of individually folded immunoglobulin-like domains as well as largely unstructured unique sequences. These mechanical elements have distinct mechanical properties, and when combined, they provide the desired passive elastic properties of muscle, which are a unique combination of strength, extensibility and resilience. Single-molecule atomic force microscopy (AFM) studies demonstrated that the macroscopic behaviour of titin in intact myofibrils can be reconstituted by combining the mechanical properties of these mechanical elements measured at the single-molecule level. Here we report artificial elastomeric proteins that mimic the molecular architecture of titin through the combination of well-characterized protein domains GB1 and resilin. We show that these artificial elastomeric proteins can be photochemically crosslinked and cast into solid biomaterials. These biomaterials behave as rubber-like materials showing high resilience at low strain and as shock-absorber-like materials at high strain by effectively dissipating energy. These properties are comparable to the passive elastic properties of muscles within the physiological range of sarcomere length and so these materials represent a new muscle-mimetic biomaterial. The mechanical properties of these biomaterials can be fine-tuned by adjusting the composition of the elastomeric proteins, providing the opportunity to develop biomaterials that are mimetic of different types of muscles. We anticipate that these biomaterials will find applications in tissue engineering as scaffold and matrix for artificial muscles. PMID:20445626

  14. Teeth and bones: applications of surface science to dental materials and related biomaterials

    Jones, F. H.

    2001-05-01

    Recent years have seen a considerable upsurge in publications concerning the surface structure and chemistry of materials with biological or biomedical applications. Within the body, gas-solid interactions become relatively less significant and solid-liquid or solid-solid interfaces dominate, providing new challenges for the surface scientist. The current paper aims to provide a timely review of the use of surface analysis and modification techniques within the biomaterials field. A broad overview of applications in a number of related areas is given with particular attention focusing on those materials commonly encountered in dentistry and oral or maxillofacial implantology. Several specific issues of current interest are discussed. The interaction between synthetic and natural solids, both in the oral environment and elsewhere in the body is important in terms of adhesion, related stresses and strains and ultimately the longevity of a dental restoration, biomedical implant, or indeed the surrounding tissue. Exposure to body fluids, of course, can also affect stability, leading to the degradation or corrosion of materials within the body. Whilst this could potentially be harmful, e.g., if cytotoxic elements are released, it may alternatively provide a route to the preferential release of beneficial substances. Furthermore, in some cases, the controlled disintegration of a biomaterial is desirable, allowing the removal of an implant, e.g., without the need for further surgery. The presence of cells in the immediate bioenvironment additionally complicates the situation. A considerable amount of current research activity is targeted at the development of coatings or surface treatments to encourage tissue growth. If this is to be achieved by stimulating enhanced cell productivity, determination of the relationship between cell function and surface composition is essential.

  15. Biosorption of heavy metals from aqueous solutions using keratin biomaterials

    Zhang, Helan

    2014-01-01

    La biosorció és una tècnica eficaç per a l'eliminació de metalls pesants de les aigües residuals resultants de l'activitat humana, principalment de les activitats industrials actuals. Els biomaterials provinents de residus es consideren alternatives ideals com a nous biosorbentes donada la baixa relació del seu cost amb la seva eficàcia i alta capacitat d'adsorció per a metalls pesants. Una àmplia gamma de biomaterials de baix cost provinents de residus, alguns dels quals provenen de process...

  16. Development of Nano-biomaterials for Bone Repair

    2005-01-01

    A new kind of nano-biomaterials of nano apatite ( NA ) and polyamide8063 ( PA ) composite was prepared by direct using NA slurry. The experimental results showed that the NA content in the composite was similar to that of natural bone. Interface chemical bonding was formed between NA and PA. The NA keeps the original morphological structure with a crystal size of 10- 30 nm in width by 50- 90 nm in length with a ratio of~ 2.5 and distributed uniformly in the polymer. The synthetic nano-biomaterials could be one of the best bioactive materials for load-bearing bone repair or substitution materials.

  17. BIOMATERIAL IMPLANTS IN BONE FRACTURES PRODUCED IN RATS FIBULAS

    Shirane, Henrique Yassuhiro; Oda, Diogo Yochizumi; Pinheiro, Thiago Cerizza; Cunha, Marcelo Rodrigues da

    2015-01-01

    To evaluate the importance of collagen and hydroxyapatite in the regeneration of fractures experimentally induced in the fibulas of rats. Method: 15 rats were used. These were subjected to surgery to remove a fragment from the fibula. This site then received a graft consisting of a silicone tubes filled with hydroxyapatite and collagen. Results: Little bone neoformation occurred inside the tubes filled with the biomaterials. There was more neoformation in the tubes with collagen. Conclusion: The biomaterials used demonstrated biocompatibility and osteoconductive capacity that was capable of stimulating osteogenesis, even in bones with secondary mechanical and morphological functions such as the fibula of rats. PMID:27047813

  18. Handbook of adhesion

    Packham, D E

    2006-01-01

    This second edition of the successful Handbook of Adhesion provides concise and authoritative articles covering many aspects of the science and technology associated with adhesion and adhesives. It is intended to fill a gap between the necessarily simplified treatment of the student textbook and the full and thorough treatment of the research monograph and review article. The articles are structured in such a way, with internal cross-referencing and external literature references, that the reader can build up a broader and deeper understanding, as their needs require.This second edition includ

  19. Lactobacillus Adhesion to Mucus

    Maxwell L. Van Tassell

    2011-05-01

    Full Text Available Mucus provides protective functions in the gastrointestinal tract and plays an important role in the adhesion of microorganisms to host surfaces. Mucin glycoproteins polymerize, forming a framework to which certain microbial populations can adhere, including probiotic Lactobacillus species. Numerous mechanisms for adhesion to mucus have been discovered in lactobacilli, including partially characterized mucus binding proteins. These mechanisms vary in importance with the in vitro models studied, which could significantly affect the perceived probiotic potential of the organisms. Understanding the nature of mucus-microbe interactions could be the key to elucidating the mechanisms of probiotic adhesion within the host.

  20. Sustainable polysaccharide-based biomaterial recovered from waste aerobic granular sludge as a surface coating material

    Lin, Y.M.; Nierop, K.G.J.; Girbal-Neuhauser, E.; Adriaanse, M.; Van Loosdrecht, M.C.M.

    2015-01-01

    To evaluate the possibility of utilizing polysaccharide-based biomaterial recovered from aerobic granular sludge as a coating material, the morphology, molecular weight distribution and chemical composition of the recovered biomaterial were investigated by atomic force microscopy, size exclusion chr

  1. Biocompatibility of Bacterial Cellulose Based Biomaterials

    Omar P. Troncoso

    2012-12-01

    Full Text Available Some bacteria can synthesize cellulose when they are cultivated under adequate conditions. These bacteria produce a mat of cellulose on the top of the culture medium, which is formed by a three-dimensional coherent network of pure cellulose nanofibers. Bacterial cellulose (BC has been widely used in different fields, such as the paper industry, electronics and tissue engineering due to its remarkable mechanical properties, conformability and porosity. Nanocomposites based on BC have received much attention, because of the possibility of combining the good properties of BC with other materials for specific applications. BC nanocomposites can be processed either in a static or an agitated medium. The fabrication of BC nanocomposites in static media can be carried out while keeping the original mat structure obtained after the synthesis to form the final nanocomposite or by altering the culture media with other components. The present article reviews the issue of biocompatibility of BC and BC nanocomposites. Biomedical aspects, such as surface modification for improving cell adhesion, in vitro and in vivo studies are given along with details concerning the physics of network formation and the changes that occur in the cellulose networks due to the presence of a second phase. The relevance of biocompatibility studies for the development of BC-based materials in bone, skin and cardiovascular tissue engineering is also discussed.

  2. Surface modification of blood-contacting biomaterials by plasma-polymerized superhydrophobic films using hexamethyldisiloxane and tetrafluoromethane as precursors

    Highlights: • Biomaterials modified by nanoparticle-containing plasma polymerized films. • A superhydrophoic film was obtained, and the properties of the coating were examined. • In vitro blood compatibility tests revealed neither platelet adhesion nor fibrinogen adsorption. • Surface modification technology of medical devices: non-cytotoxic and no blood clot formation. - Abstract: This paper proposes a plasma polymerization system that can be used to modify the surface of the widely used biomaterial, polyurethane (PU), by employing low-cost hexamethyldisiloxane (HMDSO) and tetrafluoromethane (CF4) as precursors; this system features a pulsed-dc power supply. Plasma-polymerized HMDSO/CF4 (pp-HC) with coexisting micro- and nanoscale morphology was obtained as a superhydrophobic coating material by controlling the HMDSO/CF4 (fH) monomer flow ratio. The developed surface modification technology can be applied to medical devices, because it is non-cytotoxic and has favorable hemocompatibility, and no blood clots form when the device surface direct contacts. Experimental results reveal that the obtained pp-HC films contained SiOx nanoparticles randomly dispersed on the micron-scale three-dimensional network film surface. The −CF functional group, −CF2 bonding, and SiOx were detected on the film surface. The maximal water contact angle of the pp-HC coating was 161.2°, apparently attributable to the synergistic effect of the coexisting micro- and nanoscale surface morphology featuring a low surface-energy layer. The superhydrophobic and antifouling characteristics of the coating were retained even after it was rubbed 20 times with a steel wool tester. Results of in vitro cytotoxicity, fibrinogen adsorption, and platelet adhesion tests revealed favorable myoblast cell proliferation and the virtual absence of fibrinogen adsorption and platelet adhesion on the pp-HC coated specimens. These quantitative findings imply that the pp-HC coating can potentially

  3. Surface modification of blood-contacting biomaterials by plasma-polymerized superhydrophobic films using hexamethyldisiloxane and tetrafluoromethane as precursors

    Hsiao, Chaio-Ru [Department of Materials Science and Engineering, Feng Chia University, No. 100, Wenhwa Rd., Seatwen District, Taichung City 40724, Taiwan (China); Lin, Cheng-Wei [Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, No. 666, Buzih Rd., Beitun District, Taichung City 40601, Taiwan (China); Chou, Chia-Man, E-mail: cmchou@vghtc.gov.tw [Department of Surgery, Taichung Veterans General Hospital, No. 1650, Sec. 4, Taiwan Boulevard, Seatwen District, Taichung City 40705, Taiwan (China); Department of Medicine, National Yang-Ming University, No. 155, Sec. 2, Linong Street, Beitou District, Taipei City 11221, Taiwan (China); Chung, Chi-Jen, E-mail: cjchung@seed.net.tw [Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, No. 666, Buzih Rd., Beitun District, Taichung City 40601, Taiwan (China); He, Ju-Liang [Department of Materials Science and Engineering, Feng Chia University, No. 100, Wenhwa Rd., Seatwen District, Taichung City 40724, Taiwan (China)

    2015-08-15

    Highlights: • Biomaterials modified by nanoparticle-containing plasma polymerized films. • A superhydrophoic film was obtained, and the properties of the coating were examined. • In vitro blood compatibility tests revealed neither platelet adhesion nor fibrinogen adsorption. • Surface modification technology of medical devices: non-cytotoxic and no blood clot formation. - Abstract: This paper proposes a plasma polymerization system that can be used to modify the surface of the widely used biomaterial, polyurethane (PU), by employing low-cost hexamethyldisiloxane (HMDSO) and tetrafluoromethane (CF{sub 4}) as precursors; this system features a pulsed-dc power supply. Plasma-polymerized HMDSO/CF{sub 4} (pp-HC) with coexisting micro- and nanoscale morphology was obtained as a superhydrophobic coating material by controlling the HMDSO/CF{sub 4} (f{sub H}) monomer flow ratio. The developed surface modification technology can be applied to medical devices, because it is non-cytotoxic and has favorable hemocompatibility, and no blood clots form when the device surface direct contacts. Experimental results reveal that the obtained pp-HC films contained SiO{sub x} nanoparticles randomly dispersed on the micron-scale three-dimensional network film surface. The −CF functional group, −CF{sub 2} bonding, and SiO{sub x} were detected on the film surface. The maximal water contact angle of the pp-HC coating was 161.2°, apparently attributable to the synergistic effect of the coexisting micro- and nanoscale surface morphology featuring a low surface-energy layer. The superhydrophobic and antifouling characteristics of the coating were retained even after it was rubbed 20 times with a steel wool tester. Results of in vitro cytotoxicity, fibrinogen adsorption, and platelet adhesion tests revealed favorable myoblast cell proliferation and the virtual absence of fibrinogen adsorption and platelet adhesion on the pp-HC coated specimens. These quantitative findings imply

  4. Leukocyte Adhesion Deficiency (LAD)

    ... Content Marketing Share this: Main Content Area Leukocyte Adhesion Deficiency (LAD) LAD is an immune deficiency in ... are slow to heal also may have LAD. Treatment and Research Doctors prescribe antibiotics to prevent and ...

  5. Adhesion of Lunar Dust

    Walton, Otis R.

    2007-04-01

    This paper reviews the physical characteristics of lunar dust and the effects of various fundamental forces acting on dust particles on surfaces in a lunar environment. There are transport forces and adhesion forces after contact. Mechanical forces (i.e., from rover wheels, astronaut boots and rocket engine blast) and static electric effects (from UV photo-ionization and/or tribo-electric charging) are likely to be the major contributors to the transport of dust particles. If fine regolith particles are deposited on a surface, then surface energy-related (e.g., van der Walls) adhesion forces and static-electric-image forces are likely to be the strongest contributors to adhesion. Some measurement techniques are offered to quantify the strength of adhesion forces. And finally some dust removal techniques are discussed.

  6. Management of adhesive capsulitis

    Neviaser, Andrew

    2015-01-01

    Kristen L Stupay,1 Andrew S Neviaser2 1Tulane University School of Medicine, New Orleans, LA, USA; 2George Washington University Medical Faculty Associates, Washington, DC, USA Abstract: Adhesive capsulitis of the shoulder is a condition of capsular contracture that reduces both active and passive glenohumeral motion. The cause of adhesive capsulitis is not known but it is strongly associated with endocrine abnormalities such as diabetes. Diverse terminology and the absence of definitive cri...

  7. Difficulties in the Translation of Functionalized Biomaterials into Regenerative Medicine Clinical Products

    Ratcliffe, Anthony

    2011-01-01

    There are many ways to influence cell activities, and biomaterials with functional groups attached is an attractive method that clearly has the ability to modulate cell behavior. The evidence is clear that biomaterials, with or without growth factors and cells, have resulted in numerous products for the regenerative medicine field. In contrast the functionalized biomaterial products remain in the development phase.

  8. Biomaterials for the Treatment of Alzheimer’s Disease

    Hadavi, Darya; Poot, André A.

    2016-01-01

    Alzheimer’s disease (AD) as a progressive and fatal neurodegenerative disease represents a huge unmet need for treatment. The low efficacy of current treatment methods is not only due to low drug potency but also due to the presence of various obstacles in the delivery routes. One of the main barriers is the blood–brain barrier. The increasing prevalence of AD and the low efficacy of current therapies have increased the amount of research on unraveling of disease pathways and development of treatment strategies. One of the interesting areas for the latter subject is biomaterials and their applications. This interest originates from the fact that biomaterials are very useful for the delivery of therapeutic agents, such as drugs, proteins, and/or cells, in order to treat diseases and regenerate tissues. Recently, manufacturing of nano-sized delivery systems has increased the efficacy and delivery potential of biomaterials. In this article, we review the latest developments with regard to the use of biomaterials for the treatment of AD, including nanoparticles and liposomes for delivery of therapeutic compounds and scaffolds for cell delivery strategies. PMID:27379232

  9. Assessing immunological properties of biomaterials for bone regeneration applications

    Šírová, Milada

    Cambridge : ELSEVIER - WoodHead Publishing, 2014 - (Dubruel, P.; Van Vlierberghe, S.), s. 324-348 ISBN 978-0-85709-804-7 Institutional support: RVO:61388971 Keywords : immunocompatibility of biomaterials * acute and chronic inflammation * maturation of dendritic cells Subject RIV: EC - Immunology

  10. In vitro biocompatibility testing of biomaterials and medical devices.

    Müller, U

    2008-01-01

    Biomaterials used for medical devices must be thoroughly tested according to ISO 10993 before their introduction so that any negative effects on the body are known about and prevented. By using in vitro laboratory tests, dangers for patients and unnecessary animal experiments can be avoided. Here, in vitro tests for cell compatibility (cytotoxicity) and blood compatibility (haemocompatibility) are described. PMID:18605289

  11. A Multidisciplined Teaching Reform of Biomaterials Course for Undergraduate Students

    Li, Xiaoming; Zhao, Feng; Pu, Fang; Liu, Haifeng; Niu, Xufeng; Zhou, Gang; Li, Deyu; Fan, Yubo; Feng, Qingling; Cui, Fu-zhai; Watari, Fumio

    2015-01-01

    The biomaterials science has advanced in a high speed with global science and technology development during the recent decades, which experts predict to be more obvious in the near future with a more significant position for medicine and health care. Although the three traditional subjects, such as medical science, materials science and biology…

  12. Current and future biocompatibility aspects of biomaterials for hip prosthesis

    Amit Aherwar

    2015-12-01

    Full Text Available The field of biomaterials has turn into an electrifying area because these materials improve the quality and longevity of human life. The first and foremost necessity for the selection of the biomaterial is the acceptability by human body. However, the materials used in hip implants are designed to sustain the load bearing function of human bones for the start of the patient’s life. The most common classes of biomaterials used are metals, polymers, ceramics, composites and apatite. These five classes are used individually or in combination with other materials to form most of the implantation devices in recent years. Numerous current and promising new biomaterials i.e. metallic, ceramic, polymeric and composite are discussed to highlight their merits and their frailties in terms of mechanical and metallurgical properties in this review. It is concluded that current materials have their confines and there is a need for more refined multi-functional materials to be developed in order to match the biocompatibility, metallurgical and mechanical complexity of the hip prosthesis.

  13. Fundamental monomeric biomaterial diagnostics by radio frequency signal analysis.

    Ji, Jae-Hoon; Shin, Kyeong-Sik; Kang, Shinill; Lee, Soo Hyun; Kang, Ji Yoon; Kim, Sinyoung; Jun, Seong Chan

    2016-08-15

    We present a new diagnostic technique of fundamental monomeric biomaterials that do not rely on any enzyme or chemical reaction. Instead, it only uses radio frequency (RF) signal analysis. The detection and classification of basic biomaterials, such as glucose and albumin, were demonstrated. The device was designed to generate a strong resonance response with glucose solution and fabricated by simple photolithography with PDMS (Polydimethylsiloxane) well. It even was used to detect the level of glucose in mixtures of glucose and albumin and in human serum, and it operated properly and identified the glucose concentration precisely. It has a detection limit about 100μM (1.8mg/dl), and a sensitivity about 58MHz per 1mM of glucose and exhibited a good linearity in human blood glucose level. In addition, the intrinsic electrical properties of biomaterials can be investigated by a de-embedding technique and an equivalent circuit analysis. The capacitance of glucose containing samples exhibited bell-shaped Gaussian dispersion spectra around 2.4GHz. The Albumin solution did not represent a clear dispersion spectra compared to glucose, and the magnitude of resistance and inductance of albumin was higher than that of other samples. Other parameters also represented distinguishable patterns to classify those biomaterials. It leads us to expect future usage of our technique as a pattern-recognizing biosensor. PMID:27111728

  14. Cell Physiology and Interactions of Biomaterials and Matrices

    Hunkeler, D.; Vaňková, Radomíra

    2003-01-01

    Roč. 28, č. 6 (2003), s. 193-197. ISSN 0032-3918 R&D Projects: GA MŠk OC 840.20 Institutional research plan: CEZ:AV0Z5038910 Keywords : Biomaterials * Cell physiology * Encapsulation Subject RIV: CE - Biochemistry

  15. All-biomaterial supercapacitor derived from bacterial cellulose.

    Wang, Xiangjun; Kong, Debin; Zhang, Yunbo; Wang, Bin; Li, Xianglong; Qiu, Tengfei; Song, Qi; Ning, Jing; Song, Yan; Zhi, Linjie

    2016-04-28

    An all-biomaterial originated film supercapacitor has been successfully fabricated for the first time based on a unique three-dimensional bacterial cellulose (BC) derived electrode and a novel BC-based gel electrolyte. The obtained supercapacitor displays an excellent specific capacitance of 289 mF cm(-2) and an improved solution resistance of 7 Ω. PMID:27093428

  16. Immunological aspects related to the biomaterials used in bone additions

    Papakoca, Kiro; Neamtu, Raluca; Drafta, Sergiu; Dimitriu, Bogdan; Mihai, Augustin; Durbaca, Ioana

    2010-01-01

    In the last two decades, biomaterials have become of great importance for medical practice. thus, biomatrials used for bone addition or bone augmentation are used not only in orthopedics or traumatology, but also in dental medicine, especially in oral implantology to repair some bone defects small or vast in scope.

  17. Towards 4th generation biomaterials: a covalent hybrid polymer-ormoglass architecture

    Sachot, N.; Mateos-Timoneda, M. A.; Planell, J. A.; Velders, A. H.; Lewandowska, M.; Engel, E.; Castaño, O.

    2015-09-01

    Hybrid materials are being extensively investigated with the aim of mimicking the ECM microenvironment to develop effective solutions for bone tissue engineering. However, the common drawbacks of a hybrid material are the lack of interactions between the scaffold's constituents and the masking of its bioactive phase. Conventional hybrids often degrade in a non-homogeneous manner and the biological response is far from optimal. We have developed a novel material with strong interactions between constituents. The bioactive phase is directly exposed on its surface mimicking the structure of the ECM of bone. Here, polylactic acid electrospun fibers have been successfully and reproducibly coated with a bioactive organically modified glass (ormoglass, Si-Ca-P2 system) covalently. In comparison with the pure polymeric mats, the fibers obtained showed improved hydrophilicity and mechanical properties, bioactive ion release, exhibited a nanoroughness and enabled good cell adhesion and spreading after just one day of culture (rMSCs and rEPCs). The fibers were coated with different ormoglass compositions to tailor their surface properties (roughness, stiffness, and morphology) by modifying the experimental parameters. Knowing that cells modulate their behavior according to the exposed physical and chemical signals, the development of this instructive material is a valuable advance in the design of functional regenerative biomaterials.Hybrid materials are being extensively investigated with the aim of mimicking the ECM microenvironment to develop effective solutions for bone tissue engineering. However, the common drawbacks of a hybrid material are the lack of interactions between the scaffold's constituents and the masking of its bioactive phase. Conventional hybrids often degrade in a non-homogeneous manner and the biological response is far from optimal. We have developed a novel material with strong interactions between constituents. The bioactive phase is directly exposed

  18. Biomaterials for orthopaedic implants and bone regeneration

    Sargeant, Timothy David

    For bone regeneration, there is need for biodegradable, synthetic scaffolds that direct the formation of de novo mineralized tissue. Orthopaedic implants additionally require mechanical function. The work described herein attempts to address both of these needs. The general strategy involves integrating molecularly designed tissue engineering scaffolds with porous metallic foams to create hybrid materials to direct cellular behavior. Peptide amphiphiles (PAs) that self-assemble into nanofibers were designed to template hydroxyapatite mineral under biological conditions. The molecular design incorporated either serine (S) or phosphoserine S(P) and was mixed with RGDS-bearing PA to evaluate of the key parameters for mineral formation. This led to the discovery of nanoscale hydroxyapatite spheres templated on both S- and S(P)-bearing PA nanofibers. Stem cells were encapsulated in these gels and RT-PCR showed osteoblastic differentiation in all samples. Osteoblast maturation was increased in S-bearing PA compared to S(P)-bearing PA, although the reason is not yet understood. A method to create robust PA nanofiber coatings on NiTi was developed by optimizing the NiTi oxide surface chemistry, optimizing silane vapor deposition, and covalently attaching the PAs to the silanized substrate. The surfaces were characterized by XPS, SIMS, AFM, and fluorimetry. In vitro experiments demonstrated the importance of covalent attachment for cellular adhesion and proved the materials were not cytotoxic. Orthopaedic hybrid materials were created by triggering PA self-assembly within the interconnected pores of Ti foams developed by the Dunand research group. In vitro experiments demonstrate that pre-osteoblasts adhere to, proliferate on, and migrate into PA-Ti hybrids made with S(P)- and RGDS-bearing PA mixtures. The cells differentiate into mature osteoblasts and remain viable up to 28 days. In vivo studies using a rat model demonstrate osteointegration and boney ingrowth into bare

  19. Surface modification of blood-contacting biomaterials by plasma-polymerized superhydrophobic films using hexamethyldisiloxane and tetrafluoromethane as precursors

    Hsiao, Chaio-Ru; Lin, Cheng-Wei; Chou, Chia-Man; Chung, Chi-Jen; He, Ju-Liang

    2015-08-01

    This paper proposes a plasma polymerization system that can be used to modify the surface of the widely used biomaterial, polyurethane (PU), by employing low-cost hexamethyldisiloxane (HMDSO) and tetrafluoromethane (CF4) as precursors; this system features a pulsed-dc power supply. Plasma-polymerized HMDSO/CF4 (pp-HC) with coexisting micro- and nanoscale morphology was obtained as a superhydrophobic coating material by controlling the HMDSO/CF4 (fH) monomer flow ratio. The developed surface modification technology can be applied to medical devices, because it is non-cytotoxic and has favorable hemocompatibility, and no blood clots form when the device surface direct contacts. Experimental results reveal that the obtained pp-HC films contained SiOx nanoparticles randomly dispersed on the micron-scale three-dimensional network film surface. The sbnd CF functional group, sbnd CF2 bonding, and SiOx were detected on the film surface. The maximal water contact angle of the pp-HC coating was 161.2°, apparently attributable to the synergistic effect of the coexisting micro- and nanoscale surface morphology featuring a low surface-energy layer. The superhydrophobic and antifouling characteristics of the coating were retained even after it was rubbed 20 times with a steel wool tester. Results of in vitro cytotoxicity, fibrinogen adsorption, and platelet adhesion tests revealed favorable myoblast cell proliferation and the virtual absence of fibrinogen adsorption and platelet adhesion on the pp-HC coated specimens. These quantitative findings imply that the pp-HC coating can potentially prevent the formation of thrombi and provide an alternative means of modifying the surfaces of blood-contacting biomaterials.

  20. Adhesion of human gingival fibroblasts/Streptococcus mitis co-culture on the nanocomposite system Chitlac-nAg

    Cataldi, Amelia; Gallorini, Marialucia; Di Giulio, Mara; Guarnieri, Simone; Mariggiò, Maria Addolorata; Traini, Tonino; Di Pietro, Roberta; Cellini, Luigina; Marsich, Eleonora; SANCILIO, SILVIA

    2016-01-01

    Composite materials are increasingly used as dental restoration. In the field of biomaterials, infections remain the main reason of dental devices failure. Silver, in the form of nanoparticles (AgNPs), ions and salt, well known for its antimicrobial properties, is used in several medical applications in order to avoid bacterial infection. To reduce both bacterial adhesion to dental devices and cytotoxicity against eukaryotic cells, we coated BisGMA/TEGDMA methacrylic thermosets with a new mat...

  1. Electrically Conductive Epoxy Adhesives

    Lan Bai

    2011-02-01

    Full Text Available Conductive adhesives are widely used in electronic packaging applications such as die attachment and solderless interconnections, component repair, display interconnections, and heat dissipation. The effects of film thickness as functions of filler volume fraction, conductive filler size, shape, as well as uncured adhesive matrix viscosity on the electrical conduction behavior of epoxy-based adhesives are presented in this work. For this purpose, epoxy-based adhesives were prepared using conductive fillers of different size, shape, and types, including Ni powder, flakes, and filaments, Ag powder, and Cu powder. The filaments were 20 μm in diameter, and 160 or 260 μm in length. HCl and H3PO4 acid solutions were used to etch and remove the surface oxide layers from the fillers. The plane resistance of filled adhesive films was measured using the four-point method. In all cases of conductive filler addition, the planar resistivity levels for the composite adhesive films increased when the film thickness was reduced. The shape of resistivity-thickness curves was negative exponential decaying type and was modeled using a mathematical relation. The relationships between the conductive film resistivities and the filler volume fractions were also derived mathematically based on the experimental data. Thus, the effects of surface treatment of filler particles, the type, size, shape of fillers, and the uncured epoxy viscosity could be included empirically by using these mathematical relations based on the experimental data. By utilizing the relations we proposed to model thickness-dependent and volume fraction-dependent conduction behaviors separately, we were able to describe the combined and coupled volume fraction-film thickness relationship mathematically based on our experimental data.

  2. Tuning cell adhesion by direct nanostructuring silicon into cell repulsive/adhesive patterns

    Developing platforms that allow tuning cell functionality through incorporating physical, chemical, or mechanical cues onto the material surfaces is one of the key challenges in research in the field of biomaterials. In this respect, various approaches have been proposed and numerous structures have been developed on a variety of materials. Most of these approaches, however, demand a multistep process or post-chemical treatment. Therefore, a simple approach would be desirable to develop bio-functionalized platforms for effectively modulating cell adhesion and consequently programming cell functionality without requiring any chemical or biological surface treatment. This study introduces a versatile yet simple laser approach to structure silicon (Si) chips into cytophobic/cytophilic patterns in order to modulate cell adhesion and proliferation. These patterns are fabricated on platforms through direct laser processing of Si substrates, which renders a desired computer-generated configuration into patterns. We investigate the morphology, chemistry, and wettability of the platform surfaces. Subsequently, we study the functionality of the fabricated platforms on modulating cervical cancer cells (HeLa) behaviour. The results from in vitro studies suggest that the nanostructures efficiently repel HeLa cells and drive them to migrate onto untreated sites. The study of the morphology of the cells reveals that cells evade the cytophobic area by bending and changing direction. Additionally, cell patterning, cell directionality, cell channelling, and cell trapping are achieved by developing different platforms with specific patterns. The flexibility and controllability of this approach to effectively structure Si substrates to cell-repulsive and cell-adhesive patterns offer perceptible outlook for developing bio-functionalized platforms for a variety of biomedical devices. Moreover, this approach could pave the way for developing anti-cancer platforms that selectively repel

  3. Tuning cell adhesion by direct nanostructuring silicon into cell repulsive/adhesive patterns

    Premnath, Priyatha, E-mail: priyatha.premnath@ryerson.ca [Micro/Nanofabrication Laboratory, Department of Mechanical and Industrial Engineering, Ryerson University, 350 Victoria Street, Toronto, ON, Canada M5B 2K3 (Canada); Tavangar, Amirhossein, E-mail: atavanga@ryerson.ca [Micro/Nanofabrication Laboratory, Department of Mechanical and Industrial Engineering, Ryerson University, 350 Victoria Street, Toronto, ON, Canada M5B 2K3 (Canada); Tan, Bo, E-mail: tanbo@ryerson.ca [Nanocharacterization Laboratory, Department of Aerospace Engineering, Ryerson University, 350 Victoria Street, Toronto, ON, Canada M5B 2K3 (Canada); Venkatakrishnan, Krishnan, E-mail: venkat@ryerson.ca [Micro/Nanofabrication Laboratory, Department of Mechanical and Industrial Engineering, Ryerson University, 350 Victoria Street, Toronto, ON, Canada M5B 2K3 (Canada)

    2015-09-10

    Developing platforms that allow tuning cell functionality through incorporating physical, chemical, or mechanical cues onto the material surfaces is one of the key challenges in research in the field of biomaterials. In this respect, various approaches have been proposed and numerous structures have been developed on a variety of materials. Most of these approaches, however, demand a multistep process or post-chemical treatment. Therefore, a simple approach would be desirable to develop bio-functionalized platforms for effectively modulating cell adhesion and consequently programming cell functionality without requiring any chemical or biological surface treatment. This study introduces a versatile yet simple laser approach to structure silicon (Si) chips into cytophobic/cytophilic patterns in order to modulate cell adhesion and proliferation. These patterns are fabricated on platforms through direct laser processing of Si substrates, which renders a desired computer-generated configuration into patterns. We investigate the morphology, chemistry, and wettability of the platform surfaces. Subsequently, we study the functionality of the fabricated platforms on modulating cervical cancer cells (HeLa) behaviour. The results from in vitro studies suggest that the nanostructures efficiently repel HeLa cells and drive them to migrate onto untreated sites. The study of the morphology of the cells reveals that cells evade the cytophobic area by bending and changing direction. Additionally, cell patterning, cell directionality, cell channelling, and cell trapping are achieved by developing different platforms with specific patterns. The flexibility and controllability of this approach to effectively structure Si substrates to cell-repulsive and cell-adhesive patterns offer perceptible outlook for developing bio-functionalized platforms for a variety of biomedical devices. Moreover, this approach could pave the way for developing anti-cancer platforms that selectively repel

  4. A Tubular Biomaterial Construct Exhibiting a Negative Poisson’s Ratio

    Lee, Jin Woo; Soman, Pranav; Park, Jeong Hun; Chen, Shaochen; Cho, Dong-Woo

    2016-01-01

    Developing functional small-diameter vascular grafts is an important objective in tissue engineering research. In this study, we address the problem of compliance mismatch by designing and developing a 3D tubular construct that has a negative Poisson’s ratio νxy (NPR). NPR constructs have the unique ability to expand transversely when pulled axially, thereby resulting in a highly-compliant tubular construct. In this work, we used projection stereolithography to 3D-print a planar NPR sheet composed of photosensitive poly(ethylene) glycol diacrylate biomaterial. We used a step-lithography exposure and a stitch process to scale up the projection printing process, and used the cut-missing rib unit design to develop a centimeter-scale NPR sheet, which was rolled up to form a tubular construct. The constructs had Poisson’s ratios of -0.6 ≤ νxy ≤ -0.1. The NPR construct also supports higher cellular adhesion than does the construct that has positive νxy. Our NPR design offers a significant advance in the development of highly-compliant vascular grafts. PMID:27232181

  5. Effect of carbodiimide-derivatized hyaluronic acid gelatin on preventing postsurgical intra-abdominal adhesion formation and promoting healing in a rat model.

    Yuan, Fang; Lin, Long-Xiang; Zhang, Hui-Hui; Huang, Dan; Sun, Yu-Long

    2016-05-01

    Adhesions often occur after abdominal surgery. It could cause chronic pelvic pain, intestinal obstruction, and infertility. A hydrogel biomaterial, carbodiimide-derivatized hyaluronic acid gelatin (cd-HA gelatin), has been successfully used to reduce adhesion formation after flexor tendon grafting. This study investigated the efficacy of cd-HA gelatin in preventing postsurgical peritoneal adhesions in a rat model. The surgical traumas were created on the underlying muscle of the abdominal wall and the serosal layer of the cecum. The wounds were covered with or without cd-HA gelatin. Animals were euthanized at day 14 after surgery. Adhesion formation was assessed with adhesion degree and adhesion breaking strength. The healing of abdominal wall was evaluated with biomechanical testing and histological analysis. The adhesions occurred in all rats (n = 12) without cd-HA gelatin treatment. The application of cd-HA gelatin significantly reduced the adhesion rate from 100% to 58%. The decrease of adhesion breaking strength also manifested that cd-HA gelatin could reduce postsurgical intra-abdominal adhesion formation. Moreover, it was found that cd-HA gelatin was a safe material and could promote tissue healing. The cd-HA gelatin hydrogel could reduce the formation of intra-abdominal adhesions without adversely effects on wound healing. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1175-1181, 2016. PMID:26749008

  6. Adhesive B-doped DLC films on biomedical alloys used for bone fixation

    A A Ahmad; A M Alsaad

    2007-08-01

    The long-term failure of the total hip and knee prostheses is attributed to the production of wear particles at the articulating interface between the metals, ceramics and polymers used for surgical implants and bone-fixtures. Therefore, finding an adhesive and inert coating material that has low frictional coefficient should dramatically reduce the production of wear particles and hence, prolong the life time of the surgical implants. The novel properties of the non-toxic diamond-like carbon (DLC) coatings have proven to be excellent candidates for biomedical applications. However, they have poor adhesion strength to the alloys and biomaterials. The addition of a thin interfacial layer such as Si, Ti, TiN, Mo and Cu/Cr and/or adding additives such as Si, F, N, O, W, V, Co, Mo, Ti or their combinations to the DLC films has been found to increase the adhesion strength substantially. In our study, grade 316L stainless steel and grade 5 titanium alloy (Ti–6Al–4V) were used as biomaterial substrates. They were coated with DLC films containing boron additives at various levels using various Si interfacial layer thicknesses. The best film adhesion was achieved at 8% and 20% on DLC coated Ti–6Al–4V and grade 316L substrates, respectively. It has been demonstrated that doping the DLC with boron increases their adhesion strength to both substrates even without silicon interfacial layer and increases it substantially with optimum silicon layer thickness. The adhesion strength is also correlated with the hydrogen contents in the B-DLC films. It is found to reach its maximum value of 700 kg/cm2 and 390 kg/cm2 at 2/7 and 3/6 for CH4/Ar partial pressures (in mTorr ratio) for Ti–6Al–4V and 316L substrates, respectively.

  7. Global gene expression analysis for evaluation and design of biomaterials

    Nobutaka Hanagata, Taro Takemura and Takashi Minowa

    2010-01-01

    Full Text Available Comprehensive gene expression analysis using DNA microarrays has become a widespread technique in molecular biological research. In the biomaterials field, it is used to evaluate the biocompatibility or cellular toxicity of metals, polymers and ceramics. Studies in this field have extracted differentially expressed genes in the context of differences in cellular responses among multiple materials. Based on these genes, the effects of materials on cells at the molecular level have been examined. Expression data ranging from several to tens of thousands of genes can be obtained from DNA microarrays. For this reason, several tens or hundreds of differentially expressed genes are often present in different materials. In this review, we outline the principles of DNA microarrays, and provide an introduction to methods of extracting information which is useful for evaluating and designing biomaterials from comprehensive gene expression data.

  8. Validation of the Osteopenia Sheep Model for Orthopaedic Biomaterial Research

    Ding, Ming; Danielsen, C.C.; Cheng, L.;

    2009-01-01

    resemble osteoporosis in humans. This study aimed to validate glucocorticoid-induced osteopenia sheep model for orthopaedic implant and biomaterial research. We hypothesized that a 7-month GC treatment together with restricted diet but without OVX would induce osteopenia. Materials and Methods: Eighteen......Validation of the Osteopenia Sheep Model for Orthopaedic Biomaterial Research +1Ding, M; 2Danielsen, CC; 1Cheng, L; 3Bollen, P; 4Schwarz, P; 1Overgaard, S +1Dept of Orthopaedics O, Odense University Hospital, Denmark, 2Dept of Connective Tissue Biology, University of Aarhus, Denmark, 3Biomedicine...... patients do not have a normal bone quality that in many cases are due to osteoporosis (OP) even in osteoarthritic joints. Although a variety of ovariectomized (OVX) animals has been used to study osteoporosis, there is a great need for suitable large animal models with adequate bone size that closely...

  9. Fabrication of PEGylated fibrinogen: a versatile injectable hydrogel biomaterial.

    Mironi-Harpaz, Iris; Berdichevski, Alexandra; Seliktar, Dror

    2014-01-01

    Hydrogels are one of the most versatile biomaterials in use for tissue engineering and regenerative medicine. They are assembled from either natural or synthetic polymers, and their high water content gives these materials practical advantages in numerous biomedical applications. Semisynthetic hydrogels, such as those that combine synthetic and biological building blocks, have the added advantage of controlled bioactivity and material properties. In myocardial regeneration, injectable hydrogels premised on a semisynthetic design are advantageous both as bioactive bulking agents and as a delivery vehicle for controlled release of bioactive factors and/or cardiomyocytes. A new semisynthetic hydrogel based on PEGylated fibrinogen has been developed to address the many requirements of an injectable biomaterial in cardiac restoration. This chapter highlights the fundamental aspects of making this biomimetic hydrogel matrix for cardiac applications. PMID:25070327

  10. Nanoindentation Studies of TNZ and Ti2448 Biomaterials After Magnetoelectropolishing

    Hryniewicz T.

    2014-10-01

    Full Text Available This work presents the nanoindentation results of two newly developed titanium alloy biomaterials, TNZ and Ti2448, after different surface treatments. The investigations were performed on the samples, AR – as received, MP – after abrasive polishing, EP – after a standard electropolshing, and MEP – after magnetoelectropolishing. The electropolishing processes, both EP and MEP, were conducted in the same proprietary electrolyte based on concentrated sulfuric acid. The mechanical properties of the titanium alloys biomaterials demonstrated an evident dependence on the surface treatment method, with MEP samples revealing extremely different behaviour and mechanical properties. Such a different mechanical behaviour may mean completely different composition and thickness of the surface film formed on the studied samples after MEP

  11. Modelling the regenerative niche: a major challenge in biomaterials research.

    Kirkpatrick, C James

    2015-12-01

    By definition, biomaterials are developed for clinical application. In the field of regenerative medicine their principal function is to play a significant, and, if possible, an instructive role in tissue healing. In the last analysis the latter involves targeting the 'regenerative niche'. The present paper will address the problem of simulating this niche in the laboratory and adopts a life science approach involving the harnessing of heterotypic cellular communication to achieve this, that is, the ability of cells of different types to mutually influence cellular functions. Thus, co-culture systems using human cells are the methodological focus and will concern four exemplary fields of regeneration, namely, bone, soft tissue, lower respiratory tract and airway regeneration. The working hypothesis underlying this approach is that in vitro models of higher complexity will be more clinically relevant than simple monolayer cultures of transformed cell lines in testing innovative strategies with biomaterials for regeneration. PMID:26816650

  12. Bioinspired phospholipid polymer biomaterials for making high performance artificial organs

    K Ishihara

    2000-01-01

    Full Text Available Novel polymer biomaterials, which can be used in contact with blood, are prepared with strong inspiration from the surface structure of biomembrane. That is, the polymers with a phospholipid polar group in the side chain, 2-methacrylooyloxyethyl phosphorylcholine (MPC polymers were synthesized. The MPC polymers can inhibit surface-induced clot formation effectively, when they are in contact with blood even in the absence of an anticoagulant. This phenomenon was due to the reduction of plasma protein and suppression of denaturation of adsorbed proteins, that is the MPC polymers interact with blood components very mildly. As the molecular structure of the MPC polymer was easily designed by changing the monomer units and their composition, it could be applied to surface modification of artificial organs and biomedical devices for improving blood and tissue compatibility. Thus, the MPC polymers are useful polymer biomaterials for manufacturing high performance artificial organs and biomedical devices to provide safe medical treatments.

  13. All-biomaterial supercapacitor derived from bacterial cellulose

    Wang, Xiangjun; Kong, Debin; Zhang, Yunbo; Wang, Bin; Li, Xianglong; Qiu, Tengfei; Song, Qi; Ning, Jing; Song, Yan; Zhi, Linjie

    2016-04-01

    An all-biomaterial originated film supercapacitor has been successfully fabricated for the first time based on a unique three-dimensional bacterial cellulose (BC) derived electrode and a novel BC-based gel electrolyte. The obtained supercapacitor displays an excellent specific capacitance of 289 mF cm-2 and an improved solution resistance of 7 Ω.An all-biomaterial originated film supercapacitor has been successfully fabricated for the first time based on a unique three-dimensional bacterial cellulose (BC) derived electrode and a novel BC-based gel electrolyte. The obtained supercapacitor displays an excellent specific capacitance of 289 mF cm-2 and an improved solution resistance of 7 Ω. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr01485b

  14. Simplified process for preparation of schizophyllan solutions for biomaterial applications.

    Sutivisedsak, Nongnuch; Leathers, Timothy D; Biresaw, Girma; Nunnally, Melinda S; Bischoff, Kenneth M

    2016-04-01

    Schizophyllan is a biopolymer commercially produced for pharmaceutical and cosmetics uses. However, schizophyllan also has potential biomaterial applications. Schizophyllan is conventionally produced from glucose and recovered by diafiltration and ultrafiltration to produce a highly purified product. Here we demonstrate a simplified process for preparation of schizophyllan solutions for biomaterial applications. Schizophyllan was produced in 1.5-L bioreactors from distiller's dried grains with solubles (DDGS), an abundant coproduct of dry grind fuel ethanol production. Downstream processing eliminated filtration and concentration steps, providing solutions containing 4.2 ± 0.3 g schizophyllan/L. Solutions contained high-molecular-weight schizophyllan and exhibited viscosity properties similar to those of commercial schizophyllan. Schizophyllan solutions showed promise as a component of biolubricants in friction and wear tests and by dynamic surface and interfacial tension measurements. PMID:25830418

  15. APPLICATIONS OF BIOTECHNOLOGY IN DEVELOPMENT OF BIOMATERIALS: NANOTECHNOLOGY AND BIOFILMS

    Brigmon, R.; Berry, T.; Narayan, R.

    2010-11-29

    Biotechnology is the application of biological techniques to develop new tools and products for medicine and industry. Due to various properties including chemical stability, biocompatibility, and specific activity, e.g. antimicrobial properties, many new and novel materials are being investigated for use in biosensing, drug delivery, hemodialysis, and other medical applications. Many of these materials are less than 100 nanometers in size. Nanotechnology is the engineering discipline encompassing designing, producing, testing, and using structures and devices less than 100 nanometers. One of the challenges associated with biomaterials is microbial contamination that can lead to infections. In recent work we have examined the functionalization of nanoporous biomaterials and antimicrobial activities of nanocrystalline diamond materials. In vitro testing has revealed little antimicrobial activity against Pseudomonas fluorescens bacteria and associated biofilm formation that enhances recalcitrance to antimicrobial agents including disinfectants and antibiotics. Laser scanning confocal microscopy studies further demonstrated properties and characteristics of the material with regard to biofilm formation.

  16. Adhesive strength of bioactive oxide layers fabricated on TNTZ alloy by three different alkali-solution treatments.

    Takematsu, E; Cho, K; Hieda, J; Nakai, M; Katsumata, K; Okada, K; Niinomi, M; Matsushita, N

    2016-08-01

    Bioactive oxide layers were fabricated on Ti-29Nb-13Ta-4.6Zr alloy (TNTZ) by three different alkali solution treatments: hydrothermal (H), electrochemical (E), and hydrothermal-electrochemical (HE). The adhesive strength of the oxide layer to the TNTZ substrate was measured to determine whether this process achieves sufficient adhesive strength for implant materials. Samples subjected to the HE process, in which a current of 15mA/cm(2) was applied at 90°C for 1h (HE90-1h), exhibited a comparatively higher adhesive strength of approximately 18MPa while still maintaining a sufficiently high bioactivity. Based on these results, an oxide layer fabricated on TNTZ by HE90-1h is considered appropriate for practical biomaterial application, though thicker oxide layers with many cracks can lead to a reduced adhesive strength. PMID:26866453

  17. Platelet adhesion studies on dipyridamole coated polyurethane surfaces

    Aldenhoff Y. B.J.

    2003-06-01

    Full Text Available Surface modification of polyurethanes (PUs by covalent attachment of dipyridamole (Persantinregistered is known to reduce adherence of blood platelets upon exposure to human platelet rich plasma (PRP. This effect was investigated in further detail. First platelet adhesion under static conditions was studied with four different biomaterial surfaces: untreated PU, PU immobilised with conjugate molecule 1, PU immobilised with conjugate molecule 2, and PU immobilised with conjugate molecule 3. In PU immobilised with 1 dipyridamole is directly linked to the surface, in PU immobilised with 2 there is a short hydrophilic spacer chain in between the surface and the dipyridamole, while conjugate molecule 3 is merely the spacer chain. Scanning electron microscopy (SEM was used to characterise platelet adhesion from human PRP under static conditions, and fluorescence imaging microscopy was used to study platelet adhesion from whole blood under flow. SEM experiments encompassed both density measurements and analysis of the morphology of adherent platelets. In the static experiments the surface immobilised with 2 showed the lowest platelet adherence. No difference between the three modified surfaces emerged from the flow experiments. The surfaces were also incubated with washed blood platelets and labeled with Oregon-Green Annexin V. No capture of Oregon-Green Annexin V was seen, implying that the adhered platelets did not expose any phosphatidyl serine at their exteriour surface.

  18. Bone formation following implantation of bone biomaterials into extraction sites

    Molly, Liene; Vandromme, Heleen; Quirynen, Marc; Schepers, Evert; Adams, Jessica L; van Steenberghe, Daniel

    2008-01-01

    Background: Adequate bone volume is imperative for the osseointegration of endosseous implants, but post-extraction resorption and remodeling may challenge implant placement. The use of bone biomaterials has been advocated to fill extraction sites and to enhance primary implant stability during osseointegration. The objective of the case series was to evaluate bone formation histologically and biomechanically in extraction sites following implantation of three commercially available bone biom...

  19. Scanning Probe Microscopy as a Tool for Investigation of Biomaterials

    Veronika Novotna; Alexandr Knapek; Pavel Tomanek; Sarka Safarova

    2012-01-01

    Super-microscopic techniques like scanning tunnelling microscopy, atomic force microscopy or scanning near-field optical microscopy allows investigate micro- and/or nano-scale surfaces and structures. In this paper, both Environmental scanning electron microscope (ESEM) and Scanning near field optical microscope (SNOM) have been applied to more closely study of biomaterials. The results of visualization of human osteo-sarcoma cell line (U2OS) are compared. SNOM and ESEM yield different, howev...

  20. Musculoskeletal Regenerative Engineering: Biomaterials, Structures, and Small Molecules

    Roshan James; Laurencin, Cato T.

    2014-01-01

    Musculoskeletal tissues are critical to the normal functioning of an individual and following damage or degeneration they show extremely limited endogenous regenerative capacity. The future of regenerative medicine is the combination of advanced biomaterials, structures, and cues to re-engineer/guide stem cells to yield the desired organ cells and tissues. Tissue engineering strategies were ideally suited to repair damaged tissues; however, the substitution and regeneration of large tissue vo...

  1. Synthesis and Morphological Characterization of Block Copolymers for Improved Biomaterials

    Schricker, Scott; Palacio, Manuel; Thirumamagal, B.T.S.; Bhushan, Bharat

    2010-01-01

    Biocompatible polymers are known to act as scaffolds for the regeneration and growth of bone. Block copolymers are of interest as scaffold materials because a number of the blocks are biocompatible, and their nanostructure is easily tunable with synthetic techniques. In this paper, we report the synthesis of a novel class of biomaterials from block copolymers containing a hydrophobic block of methyl methacrylate and a hydrophilic block of either acrylic acid, dimethyl acrylamide, or 2-hydroxy...

  2. Bioactive Titania Layer Fabricated on Metallic Biomaterials by Electrodeposition

    Miyazaki, T.; Otsuyama, T.; Ishida, E.

    2009-01-01

    Improvement of bone integration ability of metallic biomaterials is needed for long-term stable fIxation to bone tissues. Essential prerequisite for materials to show bone-integrating bioactivity is formation of apatite layer on their surfaces in body environments. Several functional groups have potential to trigger the apatite nucleation. In the present study, we attempted fabrication of bioactive titania layer which provides Ti-OH groups effective for the apatite formation on bioinert metal...

  3. Nano-spectroscopy and chemical nanoscopy of biomaterials

    Bründermann, E.; Schmidt, D. A.; Kopf, I.; Havenith, M.

    2010-02-01

    A scanning near-field infrared microscopy experimental station will be integrated into the ANKA-IR2 beamline to combine broadband synchrotron radiation with near-field microscopy. Other microscopy techniques also available in the station will be compared. We have performed nano-spectroscopy investigating biomaterials like self-assembled monolayers and nanoscale lipid membranes. Coherent synchrotron radiation (CSR) at ANKA has been measured to determine power and beam profile for coupling terahertz radiation to the nanoscope.

  4. Advantages of RGD peptides for directing cell association with biomaterials

    Bellis, Susan L.

    2011-01-01

    Despite many years of in vitro research confirming the effectiveness of RGD in promoting cell attachment to a wide variety of biomaterials, animal studies evaluating tissue responses to implanted RGD-functionalized substrates have yielded more variable results The goals of this report are to present some of the reasons why cell culture studies may not always reliably predict in vivo responses, and more importantly, to highlight potential applications that may benefit from the use of RGD pepti...

  5. Polysaccharide-based biomaterials with antimicrobial and antioxidant properties

    Véronique Coma

    2013-01-01

    Active packaging is one of the responses to the recent food-borne microbial outbreaks and to the consumer’s demand for high quality food and for packaging that is more advanced and creative than what is currently offered. Moreover, with the recent increase in ecological awareness associated with the dramatic decrease in fossil resources, research has turned towards the elaboration of more natural materials. This paper provides a short review of biomaterials exhibiting antimicrobial and antiox...

  6. Structural changes in sheep tibia bone undergoing biomaterial scaffold implant

    Maxwell, Craig, 1984-

    2012-01-01

    Bone fracture is a common occurrence with most people having, or knowing someone who has experienced it. This thesis displays quantitative results on the growth and strength of new material formed in a fracture gap by analysing the density and volume of the implanted biomaterial scaffold and the new material formed alongside gait and Finite Element Analysis (FEA) of external factors which can have an effect on the remodeling process. The main goal of this thesis is to present methods to provi...

  7. APPLICATION OF CHITOSAN-BASED BIOMATERIALS IN BIOARTIFICIAL LIVE

    BAO Zhiming; PAN Jilun; LI Li; YU Yaoting

    2006-01-01

    Bioartificial liver support system (BALS) has the potential to provide temporary support for patients with fulminant hepatic failure and consist of viable hepatocytes and scaffolding materials for hepatocytes attachment. Various scaffolding materials are used in BALS, including chitosan,which is easily obtained by deacetylation of chitin and widely applied in biomedical applications. In this paper, we introduce and discuses chitosan-based biomaterials for BALS application.

  8. Switchable Adhesion in Vacuum Using Bio-Inspired Dry Adhesives.

    Purtov, Julia; Frensemeier, Mareike; Kroner, Elmar

    2015-11-01

    Suction based attachment systems for pick and place handling of fragile objects like glass plates or optical lenses are energy-consuming and noisy and fail at reduced air pressure, which is essential, e.g., in chemical and physical vapor deposition processes. Recently, an alternative approach toward reversible adhesion of sensitive objects based on bioinspired dry adhesive structures has emerged. There, the switching in adhesion is achieved by a reversible buckling of adhesive pillar structures. In this study, we demonstrate that these adhesives are capable of switching adhesion not only in ambient air conditions but also in vacuum. Our bioinspired patterned adhesive with an area of 1 cm(2) provided an adhesion force of 2.6 N ± 0.2 N in air, which was reduced to 1.9 N ± 0.2 N if measured in vacuum. Detachment was induced by buckling of the structures due to a high compressive preload and occurred, independent of air pressure, at approximately 0.9 N ± 0.1 N. The switch in adhesion was observed at a compressive preload between 5.6 and 6.0 N and was independent of air pressure. The difference between maximum adhesion force and adhesion force after buckling gives a reasonable window of operation for pick and place processes. High reversibility of the switching behavior is shown over 50 cycles in air and in vacuum, making the bioinspired switchable adhesive applicable for handling operations of fragile objects. PMID:26457864

  9. [Quality of biomaterials in liquid- and tissue-biobanking].

    Herpel, Esther; Schmitt, Sabrina; Kiehntopf, Michael

    2016-03-01

    During the last years, many biobanks that collect and provide biomaterials as well as associated phenotypical data have been established on national and international levels. However, due to the heterogeneity in structure and process landscape between biobanks, quality issues arise, which might affect equivalence of sample quality and thus usability of biomaterials for scientific research projects as well as interoperability of biobanks.Here, we will give an overview on the influence of biobanking procedures on sample quality and on potential quality control measures for research biobanks, mainly focusing on tissue and liquid biomaterials. General infrastructural requirements as well as the influence of preanalytical variables affecting sample quality and usability are described and opportunities and drawbacks of different quality assurance procedures are discussed. As there is increasing consensus on national and international levels that evidence-based standardization and harmonization of biobank structures and workflows are urgently needed for quality-assured biobanking, recent activities in the development and implementation of an ISO Standard for biobanks will be illustrated in the last section of this article. PMID:26753866

  10. Scattering Anisotropy Measurements in Dental Tissues and Biomaterials

    Fernandez-Oliveras, A.; Rubiño, M.; Perez, M. M.

    2012-05-01

    Understanding the behaviour of light propagation in biological materials is essential for biomedical engineering and applications, and even more so when dealing with incoming biomaterials. Many methods for determining optical parameters from biological media assume that scattered light is isotropically distributed over all angles. However, an angular dependence of light scattering may exist and affect the optical behaviour of biological media. The present work seeks to experimentally analyze the scattering anisotropy in different dental tissues (enamel and dentine) and their potential substitute biomaterials (hybrid dental-resin, nano-filled composite, and zirconia ceramic) and comparatively study them. Goniometric measurements were made for four wavelengths in the visible range, allowing a spectral characterization of the materials studied. Previously, for each material, measurements were made with two different sample thicknesses at the same wavelength, checking the behaviour of the angular scattering profile. The asymmetry of experimental phase functions was considered in the recovery of the scattering anisotropy factor. The results demonstrate that the thicker sample yielded a less forward-directed scattering profile than did the thinner sample. The biomaterials analysed show angular scattering comparable to those of the tissues that they may replace. Comparisons can be made by virtue of the low uncertainties found.