Preformulation And Compatibility Studies Of Nateglinide With Selected Natural Polymers

Abstract

The present study focused on the preformulation, compatibility evaluation, and preliminary optimization of extended-release matrix tablets of Nateglinide using natural polymers, namely guar gum and xanthan gum. Preformulation studies were carried out to determine the physicochemical characteristics of the drug, including organoleptic properties, melting point, solubility profile, UV spectrophotometric analysis, calibration curve development, HPLC analysis, FTIR spectroscopy, DSC, and XRD studies. The drug exhibited a melting point in the range of 129–130°C and showed maximum absorbance at 216 nm. Calibration curves in methanol and 0.1 N HCl obeyed Beer–Lambert’s law with excellent linearity. FTIR, DSC, and XRD analyses confirmed the compatibility of Nateglinide with guar gum and xanthan gum without any significant interaction.

Preliminary optimization trials were conducted to investigate the influence of polymer concentration, polymer type, polymer combination, diluent concentration, and lubricant level on drug release behavior and tablet characteristics. Increased polymer concentration retarded drug release due to enhanced gel formation and matrix integrity. Xanthan gum exhibited stronger release-retarding properties than guar gum, whereas the combination of guar gum and xanthan gum produced a synergistic effect, resulting in controlled and sustained drug release for up to 12 hours.

The optimized formulation demonstrated satisfactory flow properties, compressibility, mechanical strength, and drug release characteristics. Overall, the study confirmed the suitability of natural polymers for the development of extended-release matrix tablets of Nateglinide with improved release control and formulation stability.