Carbohydrate Copolymers

Kallin, E., Lonn, H., Norberg, T., and Elofsson, M. (1989) Derivatization procedures for reducing oligosaccharides, Part 3 Preparation of oligosaccharide glycosylamines, and their conversion into oligosaccharide-acrylamide copolymers./. Carbohydr. Chem. 8, 597-611. 

L. A. Fransson and I. Carlstedt, Alkaline and Smith degradation of oxidized dermatan sul-phate-chondroitin sulphate copolymers, Carbohydr. Res., 36 (1974) 349-358. 

S. Farag and E. Al-Afaleq, Preparation and eharacterization of saponified delignified cellulose polyacrylonitrile-graft copolymer, Carbohydr. Polym., 48 (2002) 1-5. 

Fernandez-Saiz, R, Ocio, M. J., and Lagaron, J. M. Antibacterial chitosan-based blends with ethylenevi-nyl alcohol copolymer. Carbohydr. Polym. 80 (2010) 874-884. 

Laurienzo, R, Mahnconico, M., Motta, A., Vicinanza, A. Synthesis and characterization of a novel alginate-poly(ethylene glycol) graft copolymer. Carbohydr. Polym. 62, 274-282 (2005)... 

Liu WY, Liu YJ, Hao XH, Zeng GS, Wang W, Liu RG, Huang Y (2012) Backbone-collapsed intra- and inter-molecular self-assembly of cellulose-based dense graft copolymer. Carbohydr Polym 88 290-298... 

Hong-Mei, K., Yuan-Li, C., and Peng-Sheng, L. (2006). Synthesis, characterization and thermal sensitivity of chitosan-based graft copolymers. Carbohydrate Research 341, 2851-2857. 

Wu, Y Zheng, Y Yang, W Wang, C Hu, J FU, S. Synthesis and characterization of a novel amphiphilic chitosan-polylactide graft copolymer. Carbohydrate Polymers, 2005, 59, 165-171. 

Lactic acid and levulinic acid are two key intermediates prepared from carbohydrates [7]. Lipinsky [7] compared the properties of the lactide copolymers [130] obtained from lactic acid with those of polystyrene and polyvinyl chloride (see Scheme 4 and Table 5) and showed that the lactide polymer can effectively replace the synthetics if the cost of production of lactic acid is made viable. Poly(lactic acid) and poly(l-lactide) have been shown to be good candidates for biodegradeable biomaterials. Tsuji [131] and Kaspercejk [132] have recently reported studies concerning their microstructure and morphology. 

Fig. 15. Mixed copolymers were generated to examine the effect of changing the recognition epitope density for a biologically active series of carbohydrate-substituted polymers. Note n and m represent ratios of mannose and galactose residues, respectively.

Fig.16. A ruthenium initiator was used to create block copolymers to investigate the relationship between biological activity and the spacing of carbohydrates on the polymer backbone...

For the synthesis of carbohydrate-substituted block copolymers, it might be expected that the addition of acid to the polymerization reactions would result in a rate increase. Indeed, the ROMP of saccharide-modified monomers, when conducted in the presence of para-toluene sulfonic acid under emulsion conditions, successfully yielded block copolymers [52]. A key to the success of these reactions was the isolation of the initiated species, which resulted in its separation from the dissociated phosphine. The initiated ruthenium complex was isolated by starting the polymerization in acidic organic solution, from which the reactive species precipitated. The solvent was removed, and the reactive species was washed with additional degassed solvent. The polymerization was completed under emulsion conditions (in water and DTAB), and additional blocks were generated by the sequential addition of the different monomers. This method of polymerization was successful for both the mannose/galactose polymer and for the mannose polymer with the intervening diol sequence (Fig. 16A,B). 

In April this year, scientists in Sweden announced that they found higher-than-expected levels of acrylamide in foods that have been cooked at high temperatures, particularly those that are rich in carbohydrates. According to the FDA, it does not appear to be present in food before cooking. FDA has begun to measure acrylamide levels in various foods and will then derive some idea of the resulting dietary exposure levels. Acrylamide is not an unknown substance. Related chemicals are cleared for a variety of food packaging uses connected with creation of copolymers, but it is also listed by California s... 

Initial solid phase synthesis25 was carried out on Merrifield s resin (1 % crosslinked chloromethylated styrene/divinylbenzene copolymer, 200-400 mesh) because of its track record in solid-phase peptide synthesis.26 Unfortunately, the Merrifield resin has limitations as a carbohydrate carrier to study interactions between the carbohydrates and relevant binding proteins. The hydrophobic nature of the resin leads to nonspecific, irreversible protein adsorption.27 Later work utilized Rapp s TentaGel, an amphiphilic, polyethylene glycol resin.28... 

David, A., Kopeckova, P., Rubinstein, A., Kopecek, J., Enhanced biorecognition and internalization of HPMA copolymers containing multiple or multivalent carbohydrate side-chains by human hepatocarcinoma cells. Bioconjug Chem 12, 890-... 

Aldonolactones serve as suitable monomers for the generation of homo- and copolymers, especially through ring-opening polymerization (ROP). Among them are the carbohydrate-analogs of s-caprolactone, i.e., aldono-1,6-lactones. The first example of such derivatives and further ROP was reported by Galbis and co-workers [61], see also chapter, Synthetic polymers from readily available monosaccharides ... 

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