This study formulated and characterized metformin-loaded chitosan nanoparticles (NPs) using the ionic gelation technique and evaluated the drug release kinetics. Characterization confirmed successful drug encapsulation, with Fourier-transform infrared spectroscopy (FTIR) indicating compatibility, and X-ray diffraction (XRD) showing attenuation of characteristic metformin reflections consistent with reduced crystalline contribution after encapsulation. Particle sizes ranged from 74.28 to 86.82 nm. The NPs exhibited stable zeta potentials (+42.38 to +49.06 mV) and high entrapment efficiencies (68.42–81.26%). In vitro drug release studies at pH 7.4 and pH 2.0 demonstrated an initial burst release, followed by sustained release over 24 h. The cumulative drug release ranged from 81.92% to 97.72% at pH 7.4 and 89.4% to 98.1% at pH 2.0, with a faster release at pH 2.0. Drug release kinetics followed first-order for batch MN1, while batches MN2 and MN3 best fitted into the Higuchi model, indicating diffusion-controlled release through the chitosan polymeric network. The formulated metformin nanoparticles demonstrated significant potent dose-related and time-dependent cytotoxic effect against ovarian cancer cell lines and in vivo blood glucose lowering effect compared to the conventional dosage forms and control (p < 0.05). These findings highlight the potential of metformin-loaded chitosan NPs for sustained drug delivery, which may enhance patient compliance by reducing dosing frequency. Future studies should further explore their clinical applications.
Awchee et al. (Wed,) studied this question.