High Speed Determination of β‐Cyfluthrin in EC and SC Pesticide Formulations by Reverse Phase and Normal Phase Liquid Chromatography

Abstract

The isocratic HPLC procedures for determination of β‐cyfluthrin in two different (SC‐suspension concentrate and EC‐emulsifiable concentrate) pesticide formulations are described. High speed analytical columns for normal phase (HS Pecospher 3×3 Silica (3 µm, 3.3×0.46 cm)) and reversed phase liquid chromatography (HS Pecospher 3×3 C18, (3 µm, 3.3×0.46 cm)) were used. Normal phase liquid chromatography was conducted using a mobile phase of n‐hexane/dichloromethane (60/40, v/v) at UV detection of 265 nm; and acetonitrile/water (70/30, v/v), with UV detection at 220 nm for reversed phase liquid chromatography, respectively. The statistical evaluation for intra‐day (n=8) repeatability and inter‐day (n=3) precision assays was found to be satisfactory with high accuracy and precision results as indicated by the ANOVA test. The average percent of recovered analyte, at three concentration levels, was 100.8% with RSD=1.68% for the HS Pecospher 3×3 Silica column and 101.69% with RSD=3.25% for the HS Pecospher 3×3 C18 column. The sensitivity of the NP and RP HPLC procedures for investigated pesticides were evaluated by calculating the limit of detection (LOD) and limit of quantification (LOQ). The separation of two dominant isomers of β‐cyfluthrin were obtained with a selectivity factor (α) of 1.41 for HS Pecospher Silica column, and 1.06 for HS Pecospher C18 column.