Poly-L-lysine Coated Oral Nanoemulsion for Combined Delivery of Insulin and C-Peptide.

An attempt of co-delivery of insulin and C-peptide enclosed in linseed oil globules has been made employing a protective coating of positively charged poly-L-lysine to manage diabetes-associated complications. Oral water in oil in water (w/o/w) nanoemulsion manufactured by double emulsification method showed good entrapment efficiency of 87.6 ± 7.48% for insulin and 73.4 ± 6.44% for C-peptide. The optimized uncoated nanoemulsion showed a mean globule size of 210.6 ± 9.87 nm with a good PDI of 0.145 ± 0.033 and -21.7 ± 4.5 mV ZP. The poly-L-lysine coating of the nanoemulsion resulted in the reversal of surface charge to positive i.e. 18.3 ± 2.7 mV due to the cationic nature of poly-L-lysine. In vitro drug release showed an initial burst of 15-20% release within 4 h followed by controlled release up to 24 h. The poly-L-lysine coated nanoemulsion showed an 8.28-fold higher uptake than fluorescein isothiocyanate (FITC) solution in HCT116 intestinal cell lines. In vivo studies confirmed that orally administered insulin and C-peptide bearing coated nanoemulsion has the potential to improve glycemic control confirmed by blood glucose level under 200 mg/dL for 12 h compared to that of subcutaneous administration of insulin. The formulation was found stable at 25 °C as well as 4°C for up to 3 months. These findings show a promising approach for delivering oral insulin along with C-peptide for effective glycemic control and management of complications associated with diabetes.

Curcumin loaded poly (amidoamine) dendrimer-plamitic acid core-shell nanoparticles as anti-stress therapeutics.

Despite poor bioavailability of the drug and in vivo stability, curcumin has been reported for many pharmacological activities. Considering the potential of dendrimers as a drug delivery system, current research work is focused on the formulation and characterization of G4 PAMAM dendrimer-Palmitic acid core-shell nanoparticle-containing curcumin as antistress therapeutics to maximize the bioavailability of curcumin. Various formulations were prepared using different concentrations of palmitic acid and an optimized ratio of dendrimer and curcumin. All formulations were investigated for evaluation of physicochemical parameters, encapsulation efficiency, and in vitro release. Particle size, PDI, zeta-potential, and encapsulation efficiency of final formulation was found to be 257.9 ± 0.365 nm, 0.10 ± 0.004, 3.59 ± 0.167 mV, and 80.87%, respectively. In vitro release studies have shown that 53.62 ± 2.431% of the drug was released after 24 h. In vivo studies pharmacokinetic parameters, drug distribution, pharmacological, and toxicological were also estimated using swiss albino mice. The findings have shown the selected formulation is better than plain curcumin formulation.