Polyfamino acids

Table 1. Asymmetric hydrogenation of o<-acetamidocinnamic acid catalyzed by palladiumfll) on polyfamino acid) (5-6)...

Several other novel biodegradable polymer systems were also developed. One of these stems from the observation that many polymers used in medicine today were not initially designed for that purpose. It may be particularly useful to have available biodegradable polymers that are composed of, and will break down into, naturally occurring substances. One example is the synthesis of structurally new polyfamino acids) in which L-amino acids or dipeptides are polymerized by nonamide bonds (e.g., ester, iminocarbonate) involving the functional groups located on the amino acid side chains, rather than the extensively used approach involving the amino acid termini. 

The focus of this review is drug dehvery and tissue regeneration using natural biomaterials consisting of proteins and polymer chains of naturally occurring amino acids, or polyfamino acids) (PAAs). PAAs or polypeptides are biopolymers made from repeating units of amino acids. They differ chiefly from proteins in that they contain only one type of amino acid (monomer) and are polydisperse, whereas proteins are assemblies of various amino acids and are monodisperse [12]. In both proteins and PAAs, the amino acid side chains offer sites for attachment of various moieties that can modify the physical and biochemical... 

Poly(Amino Acids) 210 "Pseudo" PolyfAmino Acids) 213... 

PolyfAmino Acids) 211 12.6.2 Applications of Urethane-Based "Pseudo" ... 

Applications Poly(Amides) as "Pseudo" PolyfAmino Acids) 214... 

FIGURE 5.13 Pseudo polyfamino acids). Poly(carbonate) (a) and poly(arylate) (b) desaminotyrosyl-tyrosine copolymers. The R group is usually an alkyl chain. 

Protein molecules are poly(amino acids) consisting of a variety of amino add residues. The studies on piezoelwlridty of proteins naturally lead to work on synthetic polyfamino... 

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