Preparation of low molecular weight alginate by hydrogen peroxide depolymerization for tissue engineering

Oxidation reactions of alginate solution with H2O2 were performed under different conditions to prepare low molecular weight alginate, and its potential application for tissue engineering was investigated. H2O2 oxidation is an effective method for alginate depolymerization with the rate depending on reaction time, temperature, solution pH and H2O2 concentration. The structure analyses by FT-IR, elemental analysis and 13C NMR indicated that, the rupture of glucoside bonds in alginate chains into low molecular weight polymers is the basic process during H2O2 depolymerization. Oxidation of alginate under weak oxidation conditions (H2O2 0.6% (w/v), 50 °C, 1 h) did not significantly interfere in the formation of ionic junctions with calcium ions. The cross-linked alginate scaffold prepared from the obtained alginate under these conditions showed faster degradation rate than that from the unmodified alginate, due to the lower molecular weight of oxidized alginate and the formed aldehyde groups susceptible to hydrolysis.