Thai glutinous rice starch modified by ball milling and its application as a mucoadhesive polymer

This study aimed to investigate physicochemical properties and potential application as a mucoadhesive polymer of Thai glutinous rice starch modified by planetary ball milling. XRD and ATR-FTIR results indicated a reduction in crystallinity of starch after ball milling. Different ball milling times, ranging from 5 to 45 min, resulted in modified glutinous rice starch (MGRS) with different levels of crystallinity loss, and therefore varying degrees of cold water solubility, swelling capacity, and gelatinized dispersion viscosity. Investigation of mucoadhesive properties using Texture Analyzer with porcine mucosa demonstrated that MGRS tablets exhibited greater mucoadhesive abilities compared to hydroxypropyl methylcellulose tablets, but weaker than those of sodium carboxymethylcellulose tablets. Tablets made of 15-min-milled MGRS had comparable tableting, swelling and mucoadhesiveness, but lower erosion compared to 45-min-milled MGRS. Conclusively, ball milling treatment could successfully induce the mucoadhesive properties of Thai glutinous rice starch and expand its application as mucoadhesive polymer.