Gastrointestinal delivery of glipizide from carboxymethyl locust bean gumAl3+alginate hydrogel network: In vitro and in vivo performance

Sodium alginate and carboxymethyl locust bean gum (CMLBG) were reticulated in an aqueous solution of AlCl3, and this novel interpenetrating network (IPN) hydrogel encapsulated about 9398% glipizide. The degree of reticulation in the spherical IPN beads was confirmed by Fourier transform infrared spectroscopy, elemental analysis, neutralization equivalent determination, tensile strength testing, and differential scanning calorimetry analysis. An increase in the CMLBG weight ratio and the degree of crosslinking in the IPN was found to increase mean dissolution time of the encapsulated drug. The dissolution efficiency was found to be much higher in the medium at pH 7.4 than at pH 1.2. The swelling of IPN depended on the pH of the medium, and accordingly, monitored the drug release for a period of 8 h. The anomalous drug transport mechanism was presumed to be operative. High performance liquid chromatography (HPLC) analysis showed the drug's stability in the IPN during encapsulation. The IPN showed significant hypoglycemic activity on male Wistar rats for up to 10 h. This could be beneficial for diabetic patients for achieving control over blood glucose levels. (c) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013