Core-shell nano-biomaterials for controlled oral delivery and pharmacodynamic activity of glibenclamide

In this work, native xanthan polymer was chemically modified to xanthan-grafted-C16 amphiphilic copolymer. Microscopic examination revealed spherical core-shell micellar structures of the copolymer in water. The copolymer exhibited low critical association concentration (1.12 mg/l). The drug loading into copolymer was done by solvent evaporation method. Copolymer micellization enhanced water solubility of glibenclamide by 122 times. Moreover, aqueous dispersion of the copolymer showed negative zeta potential values (-25.9 to -26.6 mV). The micellar carrier extended the drug release profiles under simulated biological fluids up to 8 h. The dissolution efficiency was higher in phosphate buffer (pH 6.8) than in acidic (pH 1.2) solution. The drug release was dominated by super case II and anomalous transport mechanism depending upon the copolymer:drug ratio. DSC analysis suggested amorphous nature of the drug into the micelles. Furthermore, the micellar carriers were able to control hyperglycemia for a prolonged period and thus, had splendid outlook in diabetes management.