Chondroitin sulfate oxidation

Chitosan, sodium chondroitin sulfate, and pectin-nanofibrous mats were prepared from the respective polysaccharide/poly(ethylene oxide) blend solutions by electrospray. Unblended polysaccharide solutions showed low processability, i.e., the solutions could not be electrosprayed. The addition of 500 kDa poly(ethylene oxide) to chitosan solutions enhanced the formation of a fibrous stmcture. Sodium chondroitin sulfate/poly(ethylene oxide) and pectin/poly(ethylene oxide) blend solutions were generally too viscous to be sprayed at 25 °C, but at 70 °C the fibrous stmcture was formed [61]. 

J. E. Scott and M. J. Tigwell, Rapid oxidation of chondroitin sulfates and other glycols by periodic acid in organic solvents, Biochem. J., 123 (1971) 46P. 

P. Chan, J. Caron, G. Rosa, M. Orth, Glucosamine and chondroitin sulfate regulate gene expression and synthesis of nitric oxide and prostaglandin E (2) in articular cartilage explants, Osteoarthr. Car-til./OARS Osteoarthr. Res. Soc. 13 (5) (2005) 387. 

S. Dawlee, A. Sugandhi, B. Balakrishnan, D. Labarre, A. Jayakrish-nan. Oxidized chondroitin sulfate-cross-linked gelatin matrixes a new class of hydrogels. Biomacromolecules 6 (4) (2005) 2040-2048. 

For example, polyaniline is not readily incorporated into wool structures, however, poly(2-methox-yaniline-5-sulfonic acid (PMAS) is (Figure 11.11). The PMAS can subsequently be used to template the aniline monomer before chemical oxidation. Biological molecules such as chondroitin sulfate, dextran sulfate, and DNA have been shown to be effective molecular templates for this purpose. 

Nuclear oxidative phosphorylation is difficult to quantify. Although oxygen uptake in the nucleus can be measured, no exact P/O ratio is available. This is because only the AMP already present in the nuclear preparation can be converted to ATP any AMP added to the nuclei remains unaltered. An intriguing observation is the effect of DNase on the phosphorylation of AMP. (Allfrey has proposed that DNase blocks ATP synthesis in the nucleus indirectly namely, by inhibition of the nuclei by the histones, which after DNA extraction are no longer associated with DNA by salt linkages [35].) The enzymic extraction of 55% of the DNA in the nucleus leads to the loss of nuclear phosphorylation properties, which can be restored by adding DNA to the system. The effect of DNA is not specific because DNA can be replaced by RNA, polyadenylic acid, heparin, chondroitin sulfate, and polyethylene sulfate. Oxidative phosphorylation in thymus nuclear preparation has been confirmed in two laboratories. Whole body doses of ionizing radiation inhibited oxidative phosphorylation in thymus nuclei. 

The added polymers range from polysaccharides (heparin, chondroitin sulfate, dextran) to polyethylene oxide (PEO) and polystyrene (PS). 

The chemical adsorption of biomolecules such as chondroitin sulfate at the oxide surface provides a template for the adhesion of collagen strands that precede osseointegration. The nature of interaction of a biomaterial with a Uving tissue is best characterized by two terms osteoconduction and osteoinduction ... 

On the basis of the results of methylation, periodate oxidation, and oxidative deamination with ninhydrin, the structure shown above is proposed 50, 51a, 611)) for the repeating unit of chondroitin sulfate A. 

Polysaccharides containing carboxyl groups, such as chondroitin sulfate and hyaluronic acid, are derivatized with cysteine methyl ester by substituting carboxyl groups of polysaccharides and subsequently cross-linked by mild oxidation to form hydrogels. IPNs and semi-lPNs can also be degraded from backbone. 

---