Enhanced larvicidal, antibacterial, and photocatalytic efficacy of TiO2 nanohybrids green synthesized using the aqueous leaf extract of Parthenium hysterophorus.

Titanium dioxide nanoparticles are emerging as a biocompatible nanomaterial with multipurpose bioactivities. In this study, titanium dioxide (TiO2) nanoparticles were effectively synthesized using the aqueous leaf extracts of Parthenium hysterophorus prepared by microwave irradiation. TiO2 nanoparticles were fabricated by treating the P. hysterophorus leaf extracts with the TiO4 solution. Biologically active compounds such as alcohols, phenols, alkanes, and fluoroalkanes were involved in bioreduction of TiO4 into TiO2. The formation of green-engineered TiO2 nanoparticles was confirmed by UV-vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), and energy-dispersive X-ray (EDX) spectroscopy and further characterized by X-ray diffraction (XRD) studies. UV-vis spectroscopy analysis showed maximum absorbance at 420 nm due to surface plasmon resonance of synthesized TiO2 NPs. FTIR spectrum of the engineered TiO2 NPs showed the presence of bioactive compounds in the leaf extract, which acted as capping and reducing agents. FESEM exhibited an average size of 20-50 nm and a spherical shape of TiO2 NPs. EDX analysis indicated the presence of TiO2 NPs by observing the peaks of titanium ions. XRD results pointed out the crystalline nature of engineered TiO2 NPs. The larvicidal activity of TiO2 NPs was studied on fourth instar larvae of dengue, Zika virus, and filariasis mosquito vectors Aedes aegypti and Culex quinquefasciatus. Antimicrobial efficacy of TiO2 NPs was assessed on clinically isolated pathogens Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus vulgaris, and Staphylococcus epidermidis. Besides, we found that TiO2 NPs are able to quickly degrade the industrially harmful pigments methylene blue, methyl orange, crystal violet, and alizarin red dyes under sunlight illumination. Overall, this novel, simple, and eco-friendly approach can be of interest for the control of vector-borne diseases, as well as to formulate new bactericidal agents and to efficiently degrade dye solutions in the polluted areas.