Colloidal complexed nanocarriers: A modulated aspect in fabrication and characterization for streptozotocin-induced diabetic rats

Abstract

Despite strong antioxidant effect, less solubility, high light sensitivity and strong intermolecular interactions, phthalocyanine (Pc) show limited applications in the treatment of various ailments like diabetes, cancer and inflammation. Antioxidants mainly inhibit intracellular free radicals or scavenge formation with decrease in vascular NAD(P)H oxidase activity in case of diabetic complications. To alter the physicochemical characteristics of Pc, a modified polymer condensation method was strategized for the entrapment using hexamethylene diisocyanate cross-linked nanostructure in the form of monodispersed colloidal matrix system. The objective of the present work was to investigate the effect of Pc and Pc-loaded nanosponges in streptozotocin-diabetic rats for the reduction of hyperglycemic, hyperlipidemia and oxidative stress. The particle size, surface charge and % entrapment efficacy of optimized formulation containing β-cyclodextrin and hexamethylene diisocyanate in the ratio of 1:8 was found to be 328.12 ± 1.02 nm, −35.08 ± 0.89 mV and 75.23 ± 0.59%, respectively. The drug release profile of Pc was 87.80 ± 2.09% within the period of 36 h owing to decrease in crystalline nature of Pc and increase in solubility of nanocavities. The SEM images showed slightly spherical surface of the nanosponges with the size range of 100–300 nm. The FTIR, DSC and XRPD studies proved the entrapment by N-H stretching vibrations of urethane structure at 1567 cm−1, confirming the polyurethane polymer formation with significant loss of Pc crystallinity due to the formation of a new phase and change in the intensities of the peaks. The antidiabetic study of Pc-loaded nanosponges on streptozotocin-induced rat diabetic model showed gradual decrease in the blood glucose level, triglyceride, cholesterol, alkaline phosphatase and protein content with steady increase in weight within 28 days. It was concluded that Pc-loaded nanosponges improved bioavailability significantly (P < 0.0001) with anti-diabetic action within the period of 28 days.