Carboxymethylation of pectin: Optimization, characterization and in-vitro drug release studies.

The sequential optimization of carboxymethylation of pectin by Plackett-Burman (PB) design and response surface methodology (RSM) was reported in this study. PB design was employed to screen the six process variables (ethanol concentration, liquid-polymer ratio, NaOH concentration, CAA concentration, temperature and time). Central composite design (CCD) was used to study the interaction effects of ethanol concentration, NaOH concentration, CAA concentration and time on degree of substitution (DS) in carboxymethylated pectin (CMP).