Biomedical Implants

Proc. Symp. on Power Sources for Biomedical Implantable Applications and Ambient Temperature Lithium Batteries (Eds. B. G. Owens, N. Margalit), The Electrochemical Society Proceeding Series, PV 80-4, The Electrochemical Society, Princeton, NJ 1980, p. 321. [561 V. R. Koch, J. Electrochem. Soc, 1979, 126, 181. 

Carbon nanotubes are unique materials with specific properties [42]. There is a considerable application potential for using nanotubes in the biomedical field. However, when such materials are considered for application in biomedical implants, transport of medicines and vaccines or as biosensors, their biocompatibility needs to be established. Other carbon materials show remarkable long-term biocompatibility and biological action for use as medical devices. Preliminary data on biocompatibility of nanotubes and other novel nanostructured materials demonstrate that we have to pay attention to their possible adverse effects when then-biomedical applications are considered. 

Fig. 4.6 Voltage recovery of a lithium anode at -20°C in 1 mol/dm3 LiClO in PC versus a lithium reference electrode. Current density = 10 mA/cm2. (By permission of the Electrochemical Society N. Margalit and H.J. Canning, Proceedings of the symposia on power sources for biomedical implantable applications and ambient temperature lithium batteries, eds B.B, Owens and N, Margalit, 1980, p. 339.)...

Power Sources for Biomedical Implantable Applications and Ambient Temperature Lithium Batteries, 1980. (Ed. B.B. Owens and N. Margalit.)... 

With the increasing interest in and application of DNA and protein microarrays, biosensors, cell surface interactions, and biomedical implants, various systems and strategies for the immobilization and patterning of biomolecules have been developed and some have become well established. A wide diversity of chemical methods for biomolecule immobilization on inorganic substrates has been implemented by different research groups. Often, the choice of the method is a compromise between effectiveness, cost, and technology. In consideration of stability and durability of the attached biomolecules, certainly, the covalent attachment has to be preferred. 

Table 1 Incidences of infection of different biomedical implants and devices adapted from Dankert et al. [2]...

Carbon products ranging from conventional materials, such as electrodes for the aluminum and steel industries, to new high-technological applications, such as biomedical implants... 

Based on the high specificity of enzymatic reactions enzymatic fuel cells can be constructed compartmentless, i.e., without a physical separation of the anodic and the cathodic compartments. This allows miniaturization of the devices, e.g., for biomedical (implantable) devices and -> biosensors [iii]. 

The detectable amount of adsorbed species can be extremely low. A retention time shift of Atr=0.310 at a modest G (103 g) with w=250 pm results in only -10 17gof adsorbed mass (density 1.4 g/cm3). This mass corresponds to a very small layer, only 0.6 A thick on a 0.2 pm sphere [186]. The above approach has been used to measure protein adsorbed on latex surfaces [186-188], which is relevant to immunodiagnostic assays and biomedical implants. Complete adsorption isotherms can be measured [186] and antigen-antibody binding ratios determined [187]. 

Historically, polysiloxane elastomers have been reinforced with micron scale particles such as amorphous inorganic silica to form polysiloxane microcomposites. However, with the continued growth of new fields such as soft nanolithography, flexible polymer electronics and biomedical implant technology, there is an ever increasing demand for polysiloxane materials with better defined, improved and novel physical, chemical and mechanical properties. In line with these trends, researchers have turned towards the development of polysiloxane nanocomposites systems which incorporate a heterogeneous second phase on the nanometer scale. Over the last decade, there has been much interest in polymeric nanocomposite materials and the reader is directed towards the reviews by Alexandre and Dubois (4) or Joshi and Bhupendra (5) on the subject. 

Gunatillake, P.A., et al. Designing biostable polyurethane elastomers for biomedical implants. Aust. J. Chem. 2003, 56, 545-557. 

Socio-Economic Aspects and Scope of Bioceramic Materials and Biomedical Implants... 

The Growing Global and Regional Markets for Biomedical Implants I 15... 

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