Pharmaceutical applications biocompatibility

Similarly to the phospholipid polymers, the MPC polymers show excellent biocompatibility and blood compatibility [43—48]. These properties are based on the bioinert character of the MPC polymers, i.e., inhibition of specific interaction with biomolecules [49, 50]. Recently, the MPC polymers have been applied to various medical and pharmaceutical applications [44-47, 51-55]. The crosslinked MPC polymers provide good hydrogels and they have been used in the manufacture of soft contact lenses. We have applied the MPC polymer hydrogel as a cell-encapsulation matrix due to its excellent cytocompatibility. At the same time, to prepare a spontaneously forming reversible hydrogel, we focused on the reversible covalent bonding formed between phenylboronic acid and polyol in an aqueous system. 

One can conclude that PVA hydrogels represent an efficient encapsulation vehicle for the studied porphyrins, both water soluble and non-water soluble. Their biocompatible, biodegradable, non-toxic, and non-carcinogenic nature makes them especially effective for pharmaceutical applications, but also for environmental uses, such as advanced wastewater... 

CNTs are of importance as useful bio-nanomaterials for pharmaceutical applications and biomedical engineering. However, despite the contribution of CNTs to bio-nanomaterials for pharmaceutical applications, the potential risks of CNTs about the exposure to human health have not been adequately assessed. Toxicology issues associated with CNT inhalation, dermal toxicity, pulmonary, biodistribution, biocompatibility, blood compatibility, and elimination need to be addressed prior to their pharmacological application in humans. 

All in all, it is obvious that dextran will gain increasing importance as a carrier material in pharmaceutical applications, as a basis for bioactive derivatives and as a nanostructured device. Dextran and modified dex-trans should always be considered as a biocompatible material with a high structure-forming potential. 

Among new applications [192,193] attention has been focused on the biocompatible, bioactive, and biodegradable properties. Dopamine and several enzymes, e.g., trypsine, have been covalently bound to polyphos-phazene chain. AJso anestisics, steroids, and antibacterial agents may be linked to polyphosphazene with promising pharmaceutical applications. 

Cellulose is the most abundant organic material found in nature (13). It is the primary component of plant cell walls and is therefore a large constituent of fruits and vegetables. Since cellulose is safe for human consumption, it is commonly used as an additive in food products. Cellulose and chemical derivatives of cellulose are also widely used as excipients in pharmaceutical applications. The biocompatibility of cellulose coupled with a molecular structure that is conducive to chemical modification, has made cellulose a staple of pharmaceutical formulations. Each anhydroglucose unit of the cellulose backbone contains three hydroxyl groups that provide reactive sites for chemical substitution. Thereby, cellulose can be chemically modified in a variety of ways to yield materials with differing properties useful for diverse pharmaceutical applications. 

Natural polymers have also been used as thermo-sensitive hydrogels, either on their own or in combination with other synthetic polymers. Popular natural polymers include chitosan, cellulose derivatives, dextran, xyloglucan and gelatin (Klouda and Mikos 2008). Chitosan is a polysaccharide derived from the shells of crustaceans and is produced by deacetylation of chitin, basically through the removal of the acetyl group using a concentrated NaOH solution (Fig. 11.5). The main advantage of chitosan for medical and pharmaceutical applications is its biocompatibility and inertness when in contact with human cells (Kumar et al. 

In this chapter, the main characteristics of chitin and chitosan and the more convenient techniques used for their characterization will be presented together with their main physical properties. Furthermore, the materials obtained with these polysaccharides will be described. It is important to recall that chitin is a natural polymer that is also biocompatible and biodegradable, an important advantage for biomedical and pharmaceutical applications. Good film forming properties is valuable for packaging or other applications in the domain of materials. 

---