RESUMO
Ethylenebisdithiocarbamate (EBDC) fungicides are the most important class of organic fungicides and exhibit a high degree of carcinogenicity, mutagenicity, and neurotoxicity. For that reason, the safe application of these fungicides in practice requires a convenient method for their determination, applicable to biological fluids. We describe a high-performance liquid chromatography (HPLC) assay. After elimination of the metal which defines the product (maneb, mancozeb, zineb.) with EDTA, the resulting EBDC is derivatized with 1,2-benzenedithiol to yield a cyclocondensation product, 1,3-benzodithiole-2-thione, which can then be quantitated by reversed-phase HPLC at 365 nm using a microBondapak C18 column. The mobile phase was methanol/H2O (70:30, v/v). The assay was linear from 0.25 to 100 microg/mL. Within- and between-day precision and accuracy for this assay were better than 9% and 6%, respectively. The lower limits of detection and quantitation were estimated to be 0.1 and 0.25 microg/mL, respectively. This simple new method has been applied to determine mancozeb concentration in rat urine samples from urinary excretion studies.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Fungicidas Industriais/análise , Fungicidas Industriais/química , Maneb/análise , Maneb/química , Compostos de Sulfidrila/química , Zineb/análise , Zineb/química , Animais , Relação Dose-Resposta a Droga , Fungicidas Industriais/farmacocinética , Injeções Intraperitoneais , Maneb/farmacocinética , Ratos , Reprodutibilidade dos Testes , Zineb/farmacocinéticaRESUMO
A direct, simple, and rapid high-performance liquid chromatographic method has been developed for the determination of ethylene-thiourea (ETU) in biological fluids. Samples were chromatographed on a Lichrosorb RP8 (5 pm) column after extraction with dichloromethane. The mobile phase was a mixture of hexane/isopropyl alcohol/ethyl alcohol (93:6:1 v/v) added with 0.6 mL/L butylamine. Detection was done with a UV detector set at 243 nm. This method was validated to standard criteria. Calibration curves for ETU in 100 microL of 0.9% saline, 500 microL plasma, and 10 mL urine were linear (r2 > 0.99) from 0.05 to 30 microg/mL, 0.025 to 30 microg/mL, and 1 to 100 ng/mL, respectively. The lower limit of detection was 20 ng/mL in plasma, 25 ng/mL in 0.9% saline, and 0.5 ng/mL in urine.
