DEET is the most effective insect repellent available and has been widely used for more than half a century. Here, I review what is known about the olfactory and contact mechanisms of DEET repellency. For mosquitoes, DEET has at least two molecular targets: Odorant Receptors (ORs) mediate the effect of DEET at a distance, while unknown chemoreceptors mediate repellency upon contact. Additionall...

There is an increasing demand for air-dry performance of fluorocarbon finished materials. Thus, dyeing with different types of reactive, mono, bi, and multi-functional, dyes was evaluated as a novel treatment to create correct surface interface to maintain fluorocarbon performance without ironing or tumble drying. The effects of pre-treatment on fluorocarbon finishing of cotton fabric, a cellul...

Smoke from burning different kinds of vegetation or wood is often used as a cheap personal protection measure against mosquitos during the evening. To test the efficacy of smoke, a comparative field trial was conducted in the Wosera District, Papua New Guinea. Repellency of smoke from burning wild mango wood (Mangifera spp), leaves from betelnut (Areca catechu), wild ginger (Alpinia spp) and co...

Non-flouro copolymers containing a hydrophobic alkyl acrylate monomer (butyl acrylate/2-ethylhexyl acrylate/ lauryl acrylate) and a reactive monomer (maleic anhydride) have been synthesized using emulsion polymerization technique. The copolymer emulsions have been applied on to cotton fabric by a pad-dry-cure process and the water repellency of the fabrics before and after vigorous washes compa...

In recent years, the common bed bug, Cimex lectularius L. (Hemiptera: Cimicidae), became a major public health concern in urban communities. Bed bugs are notoriously difficult to control, and their bites are not tolerated by most people. The public has an urgent need for materials and methods to reduce bed bug introduction and bites during work, travel, or sleep. A repellent product will help a...

The methanol and ethyl acetate (EA) extracts of four species of sea lily (Himerometra magnipinna, Comaster multifidus, Comanthina sp., and Comatella maculata) were evaluated for their insecticidal activity against Yellow-fever mosquito larvae (Aedes aegypti) and their repellency against adult Asian Tiger mosquitoes (Aedes albopictus). The 24-hr minimum inhibition concentration (MIC) data reveal...

This study aims to develop eco-friendly botanical pesticides. Dried fruits of star anise (Illicium verum Hook.f. (Austrobaileyales: Schisandraceae)) were extracted with methyl alcohol (MA), ethyl acetate (EA), and petroleum ether (PE) at 25°C. The constituents were determined by gas chromatography-mass spectrometry, and the repellency and contact toxicity of the extracts against Sitophilus zeam...

This study was developed to evaluate the repellent activity of N,N-diethyl-3-methylbenzamide (DEET) against Amblyomma cajennense nymphs. Two repellent bioassays were compared and the effective concentration and repellent time were calculated. The fingertip test was accomplished to evaluate in vivo four concentrations of the compound (0.200; 0.100; 0.050 and 0.025 mg.cm⁻²) and the filter-paper b...

Improving water repellency of a metal surface is required in a wide range of industrial applications. In this study, the water repellency control of an oxygenfree copper surface was attempted by generating micro V grooves on the surface by using ultraprecision cutting technology. The results showed that the maximum contact angle of a water drop on a micro Vgrooved surface could be as high as ap...