Green synthesis of insecticidal, bactericidal, UV absorbent, sustainable paint formulations using Mentha piperita (peppermint)

The present study aims to develop a natural insect-repellent paint formulation derived from plant-based materials with UV absorption and antibacterial properties. Mentha piperita L. (peppermint) was employed in this study to prepare water extract and zinc nanoparticles. Its absorption in vacuum UV (200–400 nm) demonstrated its property of UV absorption, particle size analysis (less than 100 nm with 10% abundance of 20 nm) confirmed the formation of nanoparticles, and FTIR analysis substantiated the presence of phytochemicals and zinc interaction after composite formation with the plant material (3393.7 and 3304.3 cm⁻¹ = phenolic, 2927.8 cm⁻¹ = aliphatic, 2137.6 cm⁻¹ = aromatic, 2089.2 cm⁻¹ = aldehydes and ketones, 1623.3 cm⁻¹ = alkene). Mentha nanoparticles were added to paint formulations (plastic emulsion water based) to get UV absorbent, bacteriostatic and mosquito repellent coating solutions. The antimicrobial activity was assessed over 360 days at different intervals, demonstrating the significant antibacterial activity of the formulated paints (180 days with Mentha as compared to 7 days without the biocide). A comprehensive evaluation of paint color revealed a significant color change after the addition of plant based synthesized materials. Aedes aegypti mosquitos were used to evaluate the anti-mosquito activity of the formulated paint, and it was found to be 64.2% more efficient compared to non-biocidal formulations.