Biocompatibility of polymers

Hiroshi Fukumura received his M.Sc and Ph.D. degrees from Tohoku University, Japan. He studied biocompatibility of polymers in the Government Industrial Research Institute of Osaka from 1983 to 1988. He became an assistant professor at Kyoto Institute of Technology in 1988, and then moved to the Department of Applied Physics, Osaka University in 1991, where he worked on the mechanism of laser ablation and laser molecular implantation. Since 1998, he is a professor in the Department of Chemistry at Tohoku University. He received the Award of the Japanese Photochemistry Association in 2000, and the Award for Creative Work from The Chemical Society Japan in 2005. His main research interest is the physical chemistry of organic molecules including polymeric materials studied with various kinds of time-resolved techniques and scanning probe microscopes. 

Optimum biocompatibility of polymers in contact with cells and blood ... 

The principal concerns with the biocompatability of polymers are additives, residual monomers, and contaminants that are leachable in the body. Plastic extractables include such chemicals as base polymers, fillers, lubricants, plasticizers, antioxidants, pigments, and slip agents. They may also include reaction... 

The main requirement imposed on all polymer biomaterials applied in medicine is a combination of their desired physicochemical and physicomechanical characteristics with biocompatibility. Depending on particular applications, the biocompatibility of polymers can include various requirements, which can sometimes be contradictory to each other. Thns, in the case of artificial vessels, drainages, intraocular lenses, biosensors, or catheters, the interaction of the polymer with a biological medium should be minimized for the rehable operation of the corresponding device after implantation. In contrast, in the majority of orthopedic applications, the active interaction and fusion of an implant with a tissne is required. General requirements imposed on all medical polymers consist in non-toxicity and stability. 

Crystal Morphology Crystal morphology determines the mechanical properties, the biodegradability, and the biocompatibility of polymers. Thus, it is necessary to understand the mechanism of polymer crystallization in order to control the polymer microstructure and, thereby, its properties. The crystallinity and cavitation of polymers have been studied using optical and in situ electron microscopy as complementary techniques, among many others. 

Altankov, G., V. Thom, T. Groth, K. Jankova, G. Jonsson, and M. Ulbricht. 2000. Modulating the biocompatibility of polymer surfaces with polyjethylene glycol) Effect of fibronectin. Biomed Mater Res 52 219. 

Biocompatibility in its broadest sense refers to the ability of a material to perform with an appropriate host response in a specific situation. Any foreign material once implanted within an organism triggers a cascade of reactions called the immune or host response, which are part of the organism s defense mechanism. Several studies have been performed to evaluate the biocompatibility of polymers [193],... 

Sittinger, M., Reitzel, D., Dauner, M., Hierlemann, H., Hammer, C., Kastenbauer, E., Planck, H., Burmester, G. R., and Bujia, J. (1996), Resorbable polyesters in cartilage engineering Affinity and biocompatibility of polymer fiber structures to chondrocytes, /. Biomed. Mater. Res. 33(2) 57-63. 

Evaluating the mechanical and surface properties, toxicity and biocompatibility of polymers and devices before and after sterilisation is relevant in order to select for a given polymer or device a sterilisation process that is efficient against bacteria but is as benign as possible for the polymer, the... 

IMPROVEMENT OF THE BIOCOMPATIBILITY OF POLYMERS THROUGH SURFACE MODIFICATION... 

The formation of surface pores, the changes in the polar component of the surface free energy, and the disruption and formation of centers of specific adsorption in the course of ion bombardment considerably affect the cell adhesion at the ion-implanted polymers, which opens up new possibilities for controlling the biocompatibility of polymer materials [76,77]. Thus the changes in the dynamics of plasma protein adsorption at silicon rubber upon implantation with 150-keV, ... 

Therefore, the main advantage of biodegradable polymers could be that the products of degradation are not toxic or eliminated from the body by a natural metabolic pathway with minimal side effects (Marin, 2013). The biocompatibility of polymers is defined by the degradation products. In fact, polymers may reduce the local pH, thereby affecting the integrity of the cells in their microenvironment. Adopting new... 

Marija Pergal, MSc, works at the Department for Polymeric Materials, Institute for Chemistry, Technology and Metallurgy since 2003 as Research Scientist. Since 2007 she is also Teaching Assistant for the course Chemistry of Macromolecules at Department of Chemistry, University of Belgrade. Her research interests are focused on synthesis and characterization of siloxane homopolymers and copolymers, especially thermoplastic elastomers based on poly(butylene terephthalate) and polyurethanes, as well as polyurethane networks based on hyperbranched polyester. In addition to physico-chemical, mechanical and surface properties of polymers, her particular interest is directed towards the study of biocompatibility of polymer materials. 

The polymer carbon in "all-carbon materials is the high-temperature material par excellence. Finally, biocompatibility of polymer carbon promises a wide application as biomaterial in the future. 

Domb, A.J., Amselem, S., Maniar, M. Dumitriu, S. (Ed.) Biodegradable polymers as drug carrier systems. In Biocompatibility of polymers, Marcel Dekker, Inc., New York, 1994... 

Christopher, M.B. (2009) Biocompatibility of polymer implants for medical applications. MSc thesis. University of Akron, August 2009. 

Biocompatibility determines the interface reactions of blood and tissue cells with the surface of the biomaterial. In this context, the term hemocompatibility mainly refers to blood component reactions during contact with the biomaterial [202]. It is of great importance to test various polymer characteristics in detail before developing the elaborated design for in vivo application. Over the past years, a variety of methods have been established to determine hemo- and biocompatibility of polymer implants. In this chapter a summary of standardized and new methods is provided. 

Cell adhesion. For most applications the adhesion of cells is of fnndamental interest being the initial event of cell attachment. A simple method to quantify adherent cells is to incnbate cells over a snrface for a period of time snbsequently followed by the detachment of loosely adherent cells by gently washing the surface. Remaining cells can be labeled by flnorescent dyes and quantihed using flnorescent measnrements. Cell adhesion assays are also freqnently used to assess monocyte or platelet adhesion on polymeric snrfaces [215, 216]. In this context Hezi-Yamit et al. [217] did show that polymer hydrophilicity should be considered as a parameter to assess the biocompatibility of polymer surfaces. They showed that hydrophobic polymers such as PBMA or SIBS promote the adhesion of inflammatory activated monocytes while more hydrophilic polymers (e.g. PC (Phosphorylcholine) polymer) lead to less pro-inflammatory responses. 

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