Abstract
Background: In recent time, microwave-assisted procedures are becoming popular ecofriendly approaches in the Green Chemistry. In chemical processing, microwave irradiation is evolving as an efficient tool and has been utilized in various fields including polymer chemistry. Microwave irradiation extends its use in the carboxymethylation of polysaccharides like starch, hemicellusose and chitosan. However, to date, no study has reported the microwave-assisted carboxymethylation of xanthan gum. In this background, the aim of the present investigation was to synthesize microwaveassisted carboxymethyl xanthan gum.
Methods: In the present study, eco-friendly synthesis of carboxymethyl xanthan gum was carried out using microwave. The optimum reaction conditions for the carboxymethylation of xanthan gum were studied by independent variation of six parameters. The synthesized gum was characterized by Fourier transform infrared, X-ray diffraction, differential scanning calorimetric analysis and scanning electron microscopy. Further, to evaluate drug release behavior, matrix tablets of diltiazem hydrochloride were prepared.
Results: The results revealed maximum degree of substitution (0.818) with exposure time of 4 min, microwave power of 360 W, 3 g of NaOH, 1.5 g of monochloroacetic acid and alkalization time of 30 min. In characterization studies, non toxic and semi-crystalline nature of carboxymethyl xanthan gum was observed. The drug release data showed a significantly faster release of diltiazem hydrochloride from matrix tablets of carboxymethyl xanthan gum as compared to tablets prepared using xanthan gum.
Conclusion: We suggest that the microwave-assisted carboxymethylation is an efficient Green Chemistry method for the synthesis of carboxymethyl xanthan gum with zero toxicity rating and Super Case II transport.
Keywords: Carboxymethyl xanthan gum, degree of substitution, diltiazem hydrochloride, matrix tablet, microwave, semi crystalline nature, super case II transport.