Analysis of insecticides via SPME/GCMS / Nur Atiqah Abdullah

A method of analyzing and comparing relative amount of pesticides was studied via instrument of SPME and GC-MSD. The adsorption of pesticides was made by Supelco PDMS 100 um fiber. The samples used in this analysis were from three different brands having the same active content- allethrin. Method of adsorption was a solvent less, convenient and simple in studying the relative amount of pesticides in samples. Variables of adsorption temperature and adsorption time were studied in order to optimize the SPME adsorption condition. The samples were tested at variable temperature of 70°C, 80°C and 90°C as well as variable adsorption times of15 minutes and 30 minutes. It was determined that the optimum condition for SPME adsorption to be 80°C adsorption temperature with 30 minutes adsorption time. The peak area of pesticide recovered from the extraction via SPME at optimum condition was analyzed by GC-MSD and it was used as the determinant of recovery for other commercial insecticide sample. The desorption temperature for GC was 280°C with initial oven temperature of 60°C, hold for 2 minutes then increased to 200°C at 15°Cper minute with holding time of 2 minutes. Total GC analysis was 13.33 minutes. By using the optimized SPME and GC-MSD condition, a profile of pesticide extracted from samples were obtained and compared.