Microencapsulation of Permethrin for Outdoor Upholstery Fabric Insecticide Treatment

This study was intended to evaluate the behavior of permethrin-containing capsules. To do this, permethrin was encapsulated in an ethyl cellulose shell via a simple coacervation method and microcapsule optimization analyses were conducted. Scanning electron microscopy analysis showed that the microcapsules were spherical and smooth. The microcapsules had a slender-sized distribution, and the average particle size was 50 mu m according to laser diffraction analysis. Upholstery fabrics were treated with permethrin capsules via impregnation, printing, or coating to compare application methods. After application, the insecticidal effects of the pre-washed and post-washed fabrics were investigated. Insecticidal activity was evaluated against common house mosquitoes (Culex pipiens) using the World Health Organization's cone bioassay. The mosquitoes tended to stay away from the treated fabrics, and mortality rates on the printed, coated, and impregnated fabrics were 52 %, 51 %, and 50 %, respectively. The fabrics still repelled the mosquitoes after five washes. This study demonstrated that microcapsules can be transferred onto fabrics by coating and printing methods in addition to the conventional impregnation process, and that treated upholstery fabrics can be used commercially to protect against mosquito-borne illnesses.