Determination of the degree of deacetylation of chitosan by potentiometric titration preceded by enzymatic pretreatment

A novel method for determining the degree of deacetylation of chitosan is described This involves two-abrupt-change potentiometric titration preceded by enzymatic pretreatment (EP-TPT) with chitosanolytic enzyme (cellulase) to reduce the viscosity of chitosan solution Acidic titration is preferred for the rapid response within the two abrupt changes of pH Half-deacetylated chitosan (almost soluble in all pH range) was used to prove that the enzyme did not interfere with the measurement Compared with other methods such as H-1 NMR XRD FT-IR and linear potentiometric titration the proposed method is simple low-cost accurate reliable and easy to operate for industrial application (C) 2010 Elsevier Ltd All rights reserved