Preparation and characterization of oxidized alginate biopolymer: Effects of oxidation conditions

In the present work, oxidation alginate biopolymer with sodium periodate, using different concentrations and reaction times, was done and the influence of each oxidation condition on molecular weight of alginate was investigated. The FTIR results confirmed the occurrence of oxidation reaction, while oxidation percentage was determined by titration. It was observed that the same alginate oxidation percentage can be achieved by changing the reaction parameters i.e. the ratios of sodium periodate to number of alginate repeating units and reaction times. The viscosity and molecular weight of oxidized alginate were decreased by increasing the degree of oxidation as results of chain scission during oxidation. While, it was shown that the molecular weight of oxidized alginate with the similar oxidation percentage is not the same. In other words, in addition to the oxidation percentage the molecular weight reduction of polymer is also dependent to the oxidation parameters mainly due to different mechanisms which can be occurred during oxidation reaction in different conditions.