Biomedical Material Application

Kikuchi A, Okano T. Nanostructured designs of biomedical materials applications of cell sheet engineering to functional regenerative tissues and organs. J Control Release 2005 101(l-3) 69-84. 

Wang, M., Hench, L.L. and Bonfield, W. (1998) Bioglass/high density polyethylene composite for soft tissue applications Preparation and evaluation. Journal of Biomedical Materials Research, 42, 577-586. 

In the system which uses crystalline alexandrite as the sensor material/381 a measurement reproducibility of 1 °C is achieved over a wide temperature region from 20 to 700°C. The same technique is applied to another fiber optic thermometer system which is designed for biomedical sensing applications and uses LiSrAlF6 Cr3+ as sensor material/391 The standard deviation of the measurement recorded by this system is better than 0.01°C within the 20 Cand 50°C region. 

Teflon was introduced to the public in 1960 when the first Teflon-coated muffin pans and frying pans were sold. Like many new materials, problems were encountered. Bonding to the surfaces was uncertain at first. Eventually the bonding problem was solved. Teflon is now used for many other applications including acting as a biomedical material in artificial corneas, substitute bones for nose, skull, hip, nose, and knees ear parts, heart valves, tendons, sutures, dentures, and artificial tracheas. It has also been used in the nose cones and heat shield for space vehicles and for their fuel tanks. 

Nanotechnology promises to revolutionize a growing set of materials applications ranging from technology sectors such as semiconductor manufacturing, advanced sensors and coatings, to biomedical sectors such as drug delivery and implant... 

Many polymer-polymer complexes can be obtained by template polymerization. Applications of polyelectrolyte complexes are in membranes, battery separators, biomedical materials, etc. It can be predicted that the potential application of template polymerization products is in obtaining membranes with a better ordered structure than it is possible to obtain by mixing the components. The examples of such membranes from crosslinked polyCethylene glycol) and polyCacrylic acid) were described by Nishi and Kotaka. The membranes can be used as so-called chemical valves for medical applications. The membranes are permeable or impermeable for bioactive substances, depending on pH. 

In the field of metallic powder applications, a method of plasma spray coating suitable for biomedical materials has been developed using titanium and calcium phosphate composite powder. By means of the mechanical shock process, the appropriate composite powder was prepared, and plasma sprayed on Ti substrate under a low-pressure argon atmosphere. A porous Ti coating layer was obtained in which the surface and the inside of the pores were covered thinly with hydroxyapatite. This surface coating is expected to show excellent bone ingrowth and fixation with bone (21). 

Artificial Soft Biologies. In addition to sutures, polymers are used for a number of biomedical applications, as illustrated in Figure 5.128. Polymers used for hard structural applications such as dentures and bones are presented in this figure, but will be described in the next section. In this section, we will concentrate on polymers for soft biological material applications and will limit the description to mechanical properties as much as possible. 

Some of the most useful polyphosphazenes are fluoroalkoxy derivatives and amorphous copolymers (11.27) that are practicable as flame-retardant, hydrocarbon solvent- and oil-resistant elastomers, which have found aerospace and automotive applications. Polymers such as the amorphous comb polymer poly[bis(methoxyethoxyethoxy)phosphazene] (11.28) weakly coordinate Li " ions and are of substantial interest as components of polymeric electrolytes in battery technology. Polyphosphazenes are also of interest as biomedical materials and bioinert, bioactive, membrane-forming and bioerodable materials and hydrogels have been prepared. 

Marchant RE, Johnson SD, Schneider BH, Agger MP, Anderson JM. A hydrophilic plasma polymerized film composite with potential application as an interface for biomaterials. Journal of Biomedical Materials Research 1990, 24, 1521-1537. 

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