Analytical development, cutaneous permeation and ocular irritative potential studies of formulations of N’,N’-diethyl-mtoluamide based repellents

Autor: Santos, Juliana dos
Přispěvatelé: Adams, Andréa Inês Horn, Paim, Clésio Soldateli, Librelotto, Daniele Rubert Nogueira
Jazyk: portugalština
Rok vydání: 2019
Předmět:
Zdroj: Biblioteca Digital de Teses e Dissertações do UFSM
Universidade Federal de Santa Maria (UFSM)
instacron:UFSM
Popis: Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES N ', N'-diethyl-m-toluamide (DEET) is the most commonly repellent used against mosquito vectors of diseases such as dengue, yellow fever and chikungunya. In Brazil, DEET is found on the market in aerosol, solution, lotion and gel forms, in concentrations ranging from 6.65 to 25%. Until 2015, the pharmacopoeial method for DEET assay in bulk and solution used infrared spectroscopy, a technique little used for this purpose. In 2016 edition, this method was changed to an HPLC method. However, there is no pharmacopoeial method for the other forms. Despite the long time in the market, comparative studies on the penetration/permeation of different forms are not available, as well as studies of ocular irritation by alternative methods. In this scenario, the objective of this work was to validate an HPLC-UV method for the DEET assay in lotion, gel and solution, to evaluate the effect of the composition of the formulation on the penetration/permeation of the substance through the skin layers, and finally assess the potential for ocular irritation of formulations containing this substance available on the market by the alternative method HET-CAM. The analytical method was developed in Shimadzu chromatographic system, equipped with PDA detector, using C18 stationary phase, mobile phase composed of methanol, acetonitrile and water pH 4.5, flow rate of 1.0 mL min-1 and detection at 270 nm. The method specificity was confirmed by forced degradation tests, since in all the stress conditions used the DEET peak purity was index appropriate and good resolution between the peaks was observed. The method was linear in the range studied (2.5-100 μg mL-1) and showed good precision, since the DPRs in the two levels studied (repeatability and intermediate accuracy) were 0.05). Considering the administration route, the photostability of DEET was studied under UVC radiation. The DEET presented good photostability and it was observed zero order kinetic in the experimental conditions. The skin penetration/permeation study was performed on Franz type cells using porcine skin as a membrane and phosphate buffer pH 7.4 with 0.5% polysorbate 80 as the receptor medium. All formulations were able to cross through the skin layers, reaching the receptor medium. The amount of DEET permeated was dependent of the formulation, being lotion > gel > solution (p0,05). Considerando a via de administração, foi realizado estudo de fotoestabilidade sob radiação UVC. O DEET apresentou boa estabilidade e o estudo da cinética de degradação sobre luz UVC apresentou cinética de ordem zero. O estudo de penetração/permeação cutânea foi realizado em células do tipo Franz, utilizando pele de porco como membrana e tampão fosfato pH 7,4 adicionado de 0,5% de polissorbato 80 como meio receptor. Todas as formulações foram capazes de atravessar as camadas da pele, atingindo o meio receptor. A quantidade de DEET permeada foi dependente da formulação, sendo observada a ordem loção > gel > solução (p
Databáze: OpenAIRE
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