Synthesis of keto-biomacromolecule derivatives by oxidation of carboxymethyl cellulose using alkaline hexacyanoferrate (III) for alternative applications in biotechnology

Abstract

The oxidation kinetics of polysaccharides involving carboxymethyl cellulose (CMC) by several oxidizing agent have been investigated in more detail with shedding some light on the synthesis of their respective keto-derivatives as oxidation precursor products. However, the literature survey indicated that no reports have appeared on the oxidation kinetics of CMC or the synthesis of keto-CMC using hexacyanoferrate (III) ion. Therefore, a lack of information on the transfer of electron process in the rate-determining stage as well as the nature of such keto-derivatives obtained as a result of polysaccharides oxidation using various oxidants in aqueous solutions. Accordingly, the present study presents synthesis of diketo CMC as a biomacromolecule derivative using potassium ferricyanide in alkaline media. The experimental results revealed the formation of either monoketo or diketo-derivatives of CMC based on initial molar ratio between the two reactants. The formation of such keto derivatives was confirmed by the reaction of the oxidation products with both 2,4-dinitrophenyl hydrazine and hydroxyl amine as well as FTIR spectra. The reaction kinetics of oxidation showed unity order in [Fe(CN)₆^3-] and fractional first-orders with respect to both [CMC] and [OH^-].The obedience of the reaction behavior to the Michael-Menten kinetics was indicative to the formation of 1:1 intermediate complex prior to the rate-determining step as a pathway route for oxidation.

Keywords: Biomacromolecules; Carboxymethyl cellulose; Ferricyanide (III); Oxidation; Synthesis.