Kromatografi Lapis Tipis-Densitometri untuk Analisis Residu Pestisida Diazinon dalam Sawi Hijau (Brassica juncea L.)

Abstract

Densitometric thin layer chromatography, a simple, sensitive, and reprodusible separation method has been used for analizing diazinone residue from green mustard (Brassica juncea L.). The plants was sprayed by diazinone pesticide and harvested in vary period. Diazinone from samples were isolated by maceration method using n-hexane as solvent. Qualitative and quantitative analysis were performed on an aluminum plate that coated with silica gel 60 F254 as a stationary phase. Elution were carried out at room temperature with elution length of 9.5 cm in a 10 cm x 5 cm x 10 cm chamber and volume of 40 μL. Eluen was a mixture of hexane: ethyl acetate ( 18: 1,v / v), Camag 3 densitometric scanner was used to scan the chromatogram generated at a wavelength of 247 nm. The resulting data showed Rf value for diazinon either a standard or a sample was 0.298 ± 0.0035. Linearity obtained at range of concentration 40 ng to 320 ng, with a correlation coefficient of 0.974. A detection limit (LOD) of 88.44 ng/spot and the limit of quantitation (LOQ)268.03 ng/spot. Recovery percentage for the addition of standard diazinon were 100.25%, 100% and 88.33%. Diazinone residue levels in greens mustard on days 1, 3, 5 and 7 days after spraying diazinon were respectively 0,305; 0.256; 0,019; and 0,017 mg / kg.