Curcumin and Metformin Infinite Coordination Polymer Nanoparticles for Combined Therapy of Diabetic Mice via Intraperitoneal Injections

Metformin (Met) is one of the most commonly prescribed first-line drugs for diabetes treatment. However, it has several issues, including low bioavailability, therapeutic platform, and side effects at high doses. In order to improve the therapeutic efficiency of Met, this study proposes a strategy of using Met and curcumin (Cur) to prepare Cur-Zn(II)-Met infinite coordination polymer nanoparticles (CM ICP NPs), and combining this with intraperitoneal injections, for the treatment of diabetic mice. Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), nanoparticle analysis, cytotoxicity experiments, and mice experiments were used to investigate structure, properties, and application effects. The results showed that CM ICP NPs exhibit a high drug encapsulation rate (100%), good stability, and an absence of in vivo and in vitro toxicity. The blood glucose level of diabetic mice after treatment was reduced to 6.7 ± 0.65 mmol/L at the seventh week. In terms of therapeutic mechanism, it appears that Met and Cur can synergistically regulate blood glucose in mice from multiple paths. This study provides a promising method for the treatment of diabetes using Met and other drugs.