Effective Insect Repellent Formulation in both Surfactantless and Classical Microemulsions with a Long-Lasting Protection for Human Beings
Autor(es): Drapeau, Jeremy; Verdier, Marie; Touraud, Didier; Kroeckel, Ulla; Geier, Martin; Rose, Andreas; Kunz, Werner
Resumo: The aim of this work is to develop a new generation of repellent products with a long-lasting protection based on a natural component. para-menthane-3,8-diol (PMD). The active is first rendered soluble in a surfactant less microemulsion (H(2)O/(i)PrOH/PMD) and then in classical rnicroeniulsions. The presence of sclf-associated nanostructures is detected by dynamic light scattering (DLS). A synergetic system of surfactants (Cremophor (R) RH40 and Texapon (R) N70) is used. Additionally, 2-ethylhexane-1,3-diol and ethyl (-)-(S)-lactate are incorporated. The final product contains. as main components, 46% of H(2)O, 25% of (i)PrOH, 20% of non-H(2)O-soluble PMD, and only 4% of surfactants. Investigations of lasting protection on human volunteers are carried out using a cage test bioassay protocol and Aedes aegypti mosquitoes. A complete protection of 315 min is found on the test persons using the surfactantless microemulsion. An extension is observed with the final formulation to reach a mean of complete protection of 385 min. This study demonstrates that alternative formulations using a natural active instead of synthetic chemicals like N,N-diethyl-m-methylbenzamide (DEET) can he efficient for human protection against mosquitoes.
Palavras-Chave: Aedes aegypti; Mosquito repellent; Lactic acid; DEET; Water; Penetration; Emulsions; Cumulants; Efficacy
Imprenta: Chemistry & Biodiversity, v. 6, n. 6, p. 934-947, 2009
Identificador do objeto digital: 10.1002/cbdv.200800225
Descritores: Aedes aegypti - Repellent
Data de publicação: 2009
