Biocompatibility definitions

The properties of a pH electrode are characterized by parameters like linear response slope, response time, sensitivity, selectivity, reproducibility/accuracy, stability and biocompatibility. Most of these properties are related to each other, and an optimization process of sensor properties often leads to a compromised result. For the development of pH sensors for in-vivo measurements or implantable applications, both reproducibility and biocompatibility are crucial. Recommendations about using ion-selective electrodes for blood electrolyte analysis have been made by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) [37], IUPAC working party on pH has published IUPAC s recommendations on the definition, standards, and procedures... 

Although there are several definitions of biocompatibility, the concept named as biocompatibility is usually used to describe the ability of a material to perform a desired function without producing a negative effect on biological systems in specific... 

The term biocompatibility needs some explanation and has to be defined for each application separately. The historical definition was based on unimpaired cell growth in the presence of the test article [12]. More recent definitions of the biocompatibility of implantable devices ask for the ability of the device to perform its intended function, without eliciting any undesirable local or systemic effects in the host. 

The main general consideration that can be stated so far is 1) the smoothness of the separations 2) the absence of cell prelabeling and 3) the development of biocompatible instrumentation, which allows subpopulation lineage to be produced, which are not only usable for fundamental studies such as differentiation pathways or apoptosis studies, but also for transplantation or genetic engineering. One must have in mind that the cell is definitively the place, home, and native localization of genes and proteins. The possibility of rapid, nondestructive separation, purification, and characterization of cells (cellulomics) opens fabulous dimensions for proteomics and genomics. 

A commonly used definition of a biomaterial, endorsed by a consensus of biomaterials experts, is a nonviable material used in a medical device, intended to interact with biological systems. An essential characteristic of biomaterials is biocompatibility, defined as the ability of a material to perform with an appropriate host response in a specific application. The goal of biomaterials science is to create medical implant materials with optimal mechanical performance and stability, as well as optimal biocompatibility. 

The field of biomedical application often requires an interdisciplinary approach that combines the life sciences and medicine with materials science and engineering. For a successful application, the material must be biocompatible, meaning that the material has the ability to perform with an appropriate host response in a specific application. Due to the complicated interaction between materials and biological systems, there is no precise definition or accurate measurement of biocompatibility. 

Another issue relating to dialysis membranes is their ability to stimulate the immune system. If the dialysis filter membrane does not activate the complement system (C3a and C5a) when it comes in contact with the patient s blood, it is considered biocompatible. In the acute setting, the incidence of hypotension, fever, bronchoconstric-tion, and thrombocytopenia are lower in patients dialyzed with biocompatible filters. The most biocompatible dialyzers use a synthetic membrane of PS, PAN, or PMMA. Although not definitive, biocompatible membranes may be associated with fewer adverse events during dialysis, lower rates of hospitalization, reduced death rates, and slower declines in residual renal function. ... 

The definition of a biomaterial that has been arrived at by consensus is A biomaterial is one which possesses the ability to perform with an appropriate host response in a specific application (Williams, 1999). As subsequently stressed by Hench (2014), this definition emphasises that the term biocompatibility does not just mean absence of cytotoxicity but provides for the requirement that a material performs appropriately. This also means that different applications of a particular material enforces different conditions. As a consequence, a material, be it a metal, a ceramics or a polymer may or may not be biocompatible in different applications. 

Biocompatibility in materials is not precisely defined, and so all claims of biocompatibility should be read with caution. A useful definition, which is accepted by most experts, is Biocompatibility is the ability of a material to perform with an appropriate host response in a specific application (Williams, D.F., Definitions in Biomaterials. Proceedings of a Consensus Conference of the European Society for Biomaterials, Chester, England, 3-5 March 1986, Vol. 4, Elsevier, New York, 1987). For more information see Biomaterials Science an introduction to materials in medicine. Ratner, B.D., Hoffman, A.S., Schoen, F.J., and Lemons, J.E. (eds.). Academic Press, 1996. 

DiB Definitions in Biomaterials (1987) D.F. Williams (Ed.), Elsevier, Amsterdam, 6. Includes a discussion of biocompatibility. 

Although the above definition describes bio-based plastics rather unambiguously, some confusion still can be noticed, mainly due to the use of the inaccurate term bioplastics . The prefix bio- in bioplastics sometimes is used not to indicate the origin of the material ( biobased ) but to express a bio -functionality of the material, in general either biodegradability or biocompatibility. 

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