The antibacterial and photocatalytic properties of copper and tin doped titanium dioxide nanoparticles for the nano remediation of pesticide residues in soil

In this study, copper and tin doped TiO₂ nanocomposite (NCs) (Cu-Sn-TiO₂) were sunthesized using a precipitation method and their potential for nanoremediation of pesticide residues in soil was investigated. To characterize the physicochemical properties of the Cu-Sn-TiO₂ NCs, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy were used. To assess their antibacterial activity against Escherichia coli and Staphylococcus aureus, bacterial growth inhibition and bacterial membrane damage were measured. The photocatalytic experiment was conducted under natural climatic sunlight. The soil samples were hand-spread to a height of 5 mm in a glass tray and sprayed with an aqueous pesticide solution. The catalyst concentration that worked best was 0.01%. Validated UFLC with PDA detection was used to quantify the samples. Kinetic parameters such as rate constant (k) and DT50 were calculated using pesticide residue dissipation data. After 20 h of exposure, the Cu-Sn-TiO₂ NCs demonstrated significant antibacterial activity, reducing bacterial viability by more than 70%. Based on the formation of reactive oxygen species and the disruption of the bacterial membrane, the mechanism of the antibacterial and photocatalytic action of the Cu-Sn-TiO₂ NCs was discussed. The agricultural and environmental sectors may benefit from the Cu-Sn-TiO₂ NCs promising potential for the nanoremediation of pesticide residues in soils.