Modified apple polysaccharide capped gold nanoparticles for oral delivery of insulin.

The study entailed formulation of gold nanoparticles (AuNPs) upon reduction of chloroauric acid by modified apple polysaccharide (MAP). AuNPs were conjugated with insulin (INS) for its oral delivery to treat type 1 diabetes mellitus (DM). The size of MAP conjugated AuNPs loaded with INS was 124 ± 8.55 nm with zeta potential -10.5 ± 0.54 mV. The animal study carried out in streptozotocin induced rat model revealed that AuNPs conjugated insulin (AuNPs-INS) in high dose caused 3.36 folds decrease in blood glucose level in 240 min, whereas, orally administered INS failed to decrease the blood glucose level. The 28-day study also revealed better improvement in body weight, lipid profile, urea, creatinine and liver parameters in AuNPs-INS (high dose) for which the observed value was close with respect to intraperitoneally administrated insulin followed by medium dose of AuNPs-INS, low dose of AuNPS-INS, AuNPs alone and modified apple polysaccharide.