Biomedical applications tissue

Biomedical Applications. In the area of biomedical polymers and materials, two types of appHcations have been envisioned and explored. The first is the use of polyphosphazenes as bioinert materials for implantation in the body either as housing for medical devices or as stmctural materials for heart valves, artificial blood vessels, and catheters. A number of fluoroalkoxy-, aryloxy-, and arylamino-substituted polyphosphazenes have been tested by actual implantation ia rats and found to generate Httle tissue response (18). 

Microporous and microfibrous surfaces on metals are increasingly used in biomedical applications. A recent review by Wen et al. [60] identified advantages over metals with smooth surfaces which included early better adhesion of biomolecules and cells and firmer fixation of bone or connective tissue. 

Puskas, J.E. and Chen, Y. Biomedical application of commercial polymers and novel polyisobutylene-based thermoplastic elastomers for soft tissue replacement. Biomacromolecules, 5, 1141, 2004 GAK-GV, 7, 455 8, 526, 2004 (German). 

Chitosan has found many biomedical applications, including tissue engineering approaches. Enzymes such as chitosanase and lysozyme can degrade chitosan. However, chitosan is easily soluble in the presence of acid, and generally insoluble in neutral conditions as well as in most organic solvents due to the existence of amino groups and the high crystallinity. Therefore, many derivatives have been reported to enhance the solubility and processability of this polymer. 

Nanoparticles such as those of the heavy metals, like cadmium selenide, cadmium sulfide, lead sulfide, and cadmium telluride are potentially toxic [14,15]. The possible mechanisms by which nanoparticles cause toxicity inside cells are schematically shown in Fig. 2. They need to be coated or capped with low toxicity or nontoxic organic molecules or polymers (e.g., PEG) or with inorganic layers (e.g., ZnS and silica) for most of the biomedical applications. In fact, many biomedical imaging and detection applications of QDs encapsulated by complex molecules do not exhibit noticeable toxic effects [16]. One report shows that the tumor cells labeled with QDs survived in circulation and extravasated into tissues... 

C. Krafft and V. Sergo, Biomedical applications of Raman and infrared spectroscopy to diagnose tissues. Spectroscopy, 20, 195-218 (2006). 

In biomedical applications, transglutaminases have been used for tissue engineering materials such as enzymatically crosslinked collagen [60-63] or gelatin scaffolds [64-69]. Even melt-extruded guides based on enzymatically crosslinked macromolecules for peripheral nerve repair have been reported [70]. 

Polymers from renewable sources have received great attention over many years, predominantly due to the environmental concerns. Potato starch is a promising biopol5mier for various food, pharmaceutical, and biomedical applications because of its higher water solubility that raises its degradability and speed of degradation non-toxicity, easy availability, and abundancy. The role of starch for tissue engineering of bone, bone fixation, carrier for the controlled release... 

Artificial biologies, whelher soff or hard, can be categorized as eifher temporary (short term) or permanent (long term) in their intended application. Most, but certainly not all, polymers for biomedical applications are of the short-term type and include sutures, drug delivery devices, temporary vascular grafts and stents, tissue scaffolds. 

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