Carboxymethylation of xanthan gum was carried out by reacting xanthan gum with monochloroacetic acid in alkaline condition. FTIR spectroscopy confirmed the formation of carboxymethyl xanthan. DSC and XRD study revealed the crystalline nature of carboxymethyl xanthan. SEM images showed that carboxymethyl xanthan particles are globular in shape and smaller in size. Viscosity measurements also showed that the carboxymethyl xanthan is less viscous as compared to xanthan gum. Diclofenac sodium matrix tablets prepared using carboxymethyl xanthan revealed faster release of drug as compared with xanthan gum matrix.
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