Residue analysis of forchlorfenuron in fruit and vegetable by RP-HPLC

A method using solid-phase extraction for cleanup, followed by high-performance liquid chromatography with ultraviolet detection (HPLC/UV), was developed for the determination of forchlorfenuron residues in Fruit and vegetable. The forchlorfenuron is extracted from the sample (15 g) with ethyl acetate (30 mL), and the extract is loaded onto an ENVI-18 column. The forchlorfenuron is eluted with methanol-water as the mobile phase (65:35) and determined by HPLC/UV (260 nm). The ENVI-18 column was found to provide effective cleanup, removing the greatest number of sample matrix interferences. In this method, the correlation coefficient (R²) was 1.0000 with the linear range of forchlorfenuron from 0.1 μg mL^-1 to 10.0 μg mL^-1. At the low, medium and high three fortification levels of 0.03-5.33 mg kg^-1, forchlorfenuron average recoveries range from 84.7 % to 103.0 % and relative standard deviations (RSD) were in the range of 0.6-4.9 % for all analytes. The limits of detection (LOD) of forchlorfenuron (minimum amount injected that resulted in a peak about three times the sample baseline) was 0.02 mg kg^-1. This method was practicable for routine residue analysis of forchlorfenuron in kiwi, grape, tomato and cucumber matrices.