Biopolymers poly

DIRECT DEGRADATION OF THE BIOPOLYMER POLY[(R)-3-HYDROXYBUTYRIC ACID] TO (R)-3-HYDROXYBUTANOIC ACID AND ITS... 

More than a dozen biocompatible and biodegradable polymers have been described and studied for their potential use as carriers for therapeutic proteins (Table 13.5). However, some of the monomer building blocks such as acrylamide and its derivatives are neurotoxic. Incomplete polymerization or breakdown of the polymer may result in toxic monomer. Among the biopolymers, poly-lactide cofabricated with glycolide (PLG) is one of the most well studied and has been demonstrated to be both biocompatible and biodegradable [12]. PLG polymers are hydrolyzed in vivo and revert to the monomeric forms of glycolic and lactic acids, which are intermediates in the citric acid metabolic pathway. 

Laser desorption Fourier transform mass spectrometry (LD-FTMS) results from a series of peptides and polymers are presented. Successful production of molecular ions of peptides with masses up to 2000 amu is demonstrated. The amount of structurally useful fragmentation diminishes rapidly with increasing mass. Preliminary results of laser photodissociation experiments in an attempt to increase the available structural information are also presented. The synthetic biopolymer poly(phenylalanine) is used as a model for higher molecular weight peptides and produces ions approaching m/z 4000. Current instrument resolution limits are demonstrated utilizing a polyethylene-glycol) polymer, with unit mass resolution obtainable to almost 4000 amu. 

The blending of different polymers is a frequently used technique in industrial polymer production to optimize the material s properties. The biodegradable polymer poly(3-hydroxybutyrate) (PHB) [45, 46], for example, which can be produced by bacteria from renewable resources, has the disadvantage of being stiff and brittle. The mechanical properties of PHB, however, can be readily enhanced by blending with another biopolymer, poly(lactic acid) (PLA) [47]. In order to prepare the optimum blend, it must be noted that the miscibility of different polymers depends on their concentration, the temperature, and their structural characteristics [48]. 

The chiral 1,3-dioxanes 21 and 25 are obtained from the biopolymer poly[(i )-3-hydroxybutyric acid] (PHB) by hydrolysis providing the chiral P-hydroxy acid 26 which is condensed with aldehydes. 

M.H. Sung, C. Park, C.J. Kim, H. Poo, K. Soda, M. Ashiuchi, Natural and edible biopolymer poly-gamma-glutamic acid synthesis, production, and applications, Chem. Rec. 5 (2005) 352-366. 

Wanamaker, C.L., Tolman, W.B. and Htilmyer, M.A. (2009) 2-Biopolymers poly(D-lactide)-poly(menthide)-poly(D-lactide) triblock copolymers as crystal nucleating agents for poly(L-lactide). Macromolecular Symposia, 283-284,130-138. 

Ceo causes lower subsurface damage compared to SF5+ during the depth profile analysis of a biopolymer, poly-caprolactone [363]. Additional reports on the success of Ceo in organic depth profiling have been presented for other materials such as PLA [364], PMMA [365], trehalose [356], and a complex PVDF/PMMA-based coil coating [366]. 

Seebach, D., Beck, A.K., Breitschuh, R., Job, K., 2003. Direct degradation of the biopolymer poly[(R)-3-hydroxybutyric acid] to (R)-3-Hydroxybutanoic acid and its methyl ester. In Organic Syntheses, 71. John Wiley Sons, Inc, pp. 39—47. 

Elamia R, Zhdan PA, Martino M, Castle JE, Tamburro AM (2004) AFM study of the elastin-like biopolymer poly(ValGIyGlyValGly). Biomacromolecules 5 1511-1518... 

Versace D-L, Ramier J, Babinot J, Lemechko P, Soppera O, Lalevee J, Albanese P, Renard E, Langlois V. Photoindnced modification of the natural biopolymer poly... 

VER 13a] Versace D.-L., Ramier J., Babinot J. et al., Photoinduced modification of the natural biopolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) microfibrous surface with anthraquinone-deriveddextran for biological applications . Journal of Materials Chemistry B, vol. 1, pp. 4834-4844, 2013. 

This chapter focuses on the LbL assembly of two pairs of biopolymers, poly L-lysine (PLL)/poly L-glutamic acid (PGA) and chitosan (CHIT)/ dextran sulfate (DEX) onto a negatively charged P(NiPAM-co-MAA) NG... 

These biopolymers, poly(A/-acetyl-l,4-jS-D-glucopyranosamine) (chitin) and poly(l,4-jS-D-glucopyranosamine) (chitosan), are widely abundant in nature. Their... 

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