HYBRIDIZATION OF SNAIL EPIPHRAGM AND CHITOSAN AS A CARRIER OF ORAL INSULIN DELIVERY IN DIABETES MANAGEMENT

Abstract

Oral insulin delivery remains a mirage among the pharmaceutical scientists due to inability to circumvent its
inherent stability in gastrointestinal tract after oral administration. In this study, insulin-loaded microparticles for
oral delivery were prepared with snail epiphragm and chitosan combined at different concentrations of chitosan
using a novel method based on polymer hybridization. Four insulin-loaded batches were prepared and labeled as
FS1, FS2, FS3 and FS4 containing 1:1, 1:2, 1:3 and 1:4 of snail epiphragm (SE) and chitosan (CS), respectively.
The unloaded (drug free) batch was similarly prepared and labeled as FS0. Characterizations such as particle size,
morphology and thermal properties were evaluated. The in vitro release and blood glucose reduction after oral
administration to diabetic rats was determined. The particles formed ranged from 121.0 ± 0.12 to 59± 1.06 μm, and
were generally not spherical and varied in sizes. The loading and encapsulation efficiency were generally high. The
minimum and maximum EE were 90.5 ± 0.03 and 97.7 ± 0.22 % for FS2 and FS4, respectively. The in vitro release
of insulin from the formulations varied with the chitosan concentration, with FS1 (50 %) and FS2 (89 %). The
percentage blood glucose reduction for the subcutaneously administered insulin was significantly (p < 0.001) higher
than the formulations. In vivo studies revealed a pronounced hypoglycaemic (34.67±3.65 %) effect in diabetic rats
after peroral administration of the insulin-loaded MPs compared to the free oral insulin solution within 12h of
administration. Therefore, these findings clearly suggest that the snail epiphragm-chitosan based microparticles offer
an interesting mode of insulin delivery orally for the treatment of diabetes.