Fabric pre-treated with Vitex negundo L essential oil as a preventive tool against mosquito bite

Abstract

Despite its beneficial properties and the efficiency of essential oil in controlling mosquitoes and other hematopoietic insects, this biocontrol agent has several significant limitations, ranging from its chemical instability to its short protection time and sensitivity to oxidation. This research aimed to address these limitations by altering the surface functionality using encapsulated Vitex negundo essential oil (VnEO). The VnEO was extracted by hydrodistilation and analysed by GC–MS. The oil was β-cyclodextrin (β-CD) encapsulated and monochlorotriazine (MCT) modified to improve its fabric interaction and stability, while histological and immunohistochemical examinations were conducted to determine its safety. The fabrics were subjected to FT-IR, SEM, XRD, TGA, fiberometric, and Zeta potential analysis, while the repellency study was conducted in an olfactometer. Insecticidal monoterpenes and sesquiterpenes were confirmed by GC–MS, and an entrapment efficiency of 94.3% was achieved. The repellent interaction with the fabric was confirmed by the formation of two intense bands at 3277 (O–H) and 1710 cm−1 (C=O), broad diffraction peaks at 17.30° and 38.30–57.10° about a 4.70% increase in average fibre size and a 18.8% decrease in pore size, and lower fibre thermal stability. The surface of the fabric is negatively charged, causing an enhancement in the adsorption and affinity of VnEO by grafting of β-CD/MCT. The dermatological investigation suggests that the oil has no significant toxic effects. In conclusion, the encapsulation and fabric grafting employed are effective and safe for the preparation of a long-lasting repellent fabric.