Phytofabricated ZnO-NPs mediated by Hibiscus tiliaceus leaf extract and its potential as a diosgenin delivery vehicle

Abstract

Zinc oxide nanoparticles (ZnO-NPs) have provided promising potential in the biomedical field, including the ability to overcome various health problems. Diosgenin is used to treat multiple health disorders but has very low solubility in water. Using ZnO-NPs as a diosgenin delivery vehicle was expected to increase the solubility of diosgenin, which would affect its bioavailability. This study demonstrates phytofabrication and characterization of ZnO-NPs, loading of diosgenin onto the ZnO-NPs, characterization of the product (ZnO-NPs/diosgenin), and evaluations of diosgenin release. Phytofabrication of the ZnO-NPs was carried out with zinc precursors and Hibiscus tiliaceus leaf extract (HLE) obtained with various extraction solvents. To explore the potential of using the ZnO-NPs as a diosgenin delivery vehicle, diosgenin release from the ZnO-NPs/diosgenin was studied. Based on the X-ray fluorescence (XRF) and X-ray diffraction (XRD) results, ZnO-NPs with high purity have been successfully fabricated. Nano-sized particles were detected using scanning electron microscopy (SEM) and confirmed by transmission electron microscopy (TEM), revealing the smallest particle size of 45.924 ± 27.910 nm obtained from the methanol extract with the zinc acetate precursor. The ZnO-NPs had hexagonal wurtzite and rod-like structures. Diosgenin was successfully added to the ZnO-NPs with loadings of 79.972% for ZnO-HLMEA-D₅₀₀ (ZnO-NPs/diosgenin produced by doping with a 500 μg mL⁻¹ of diosgenin solution) and 39.775% for ZnO-HLMEA-D₁₀₀₀ (ZnO-NPs/diosgenin produced by doping with a 1000 μg mL⁻¹ of diosgenin solution). The solubilities of diosgenin from ZnO-HLMEA-D₅₀₀ and ZnO-HLMEA-D₁₀₀₀ were higher than that of free diosgenin, confirming that ZnO-NPs have potential as delivery vehicles for diosgenin and conceivably other water-insoluble drugs.