<i>In Vitro</i> Drug Release Kinetics and Antioxidant Activity of Metformin-Loaded Niosomes

Metformin is an antidiabetic drug that is widely used in the treatment of type 2 diabetes mellitus (T2DM) and is known to reduce oxidative stress. Drug-loaded niosomes enhance the cellular uptake of drugs, resulting in improved antioxidant effects. In this study, we formulated metformin-loaded niosomes, aiming to enhance cellular drug uptake and augment antioxidant effects. The particle size, polydispersity index, and zeta potential values were found to be 153.8 nm, 0.449, and -9.32 mV respectively. Morphological observations conducted through scanning electron microscopy (SEM) provided insights into the distinctive structure of the niosomes. Entrapment efficiency of drug-loaded niosomes was determined to be 68%. In vitro drug release studies, performed by using the dialysis bag method, exhibited a release profile consistent with Hixson-Crowell kinetics. After characterization of the formulations, the antioxidant activity of metformin-loaded niosomes on Pyrogallol-induced reactive oxygen species (ROS) formation in the mouse brain was compared with metformin treatment alone. ROS formation was measured by a luminol-lucigenin chemiluminescence assay. Metformin-loaded niosomes significantly reduced ROS formation compared to metformin treatment alone. Metformin-loaded niosomes offer potential for enhanced antioxidant effects and bioavailability by increasing cellular uptake of metformin.