Solid liquid extraction for the evaluation of organophosphorus content in apple after washing treatment / Muhammad Nazirul Ikram Abd Jalil

Apple is a very nutritious fruit but the used of pesticide had cause a concern to human health. Besides, apple had been considered as one of the top list of dirty frozen which is contaminated with pesticides. In this study, the amount of chlorpyrifos in apple after washing treatment and the effectiveness of the washing solution had been determined. The analysis was carried out using Reversed Phase High Performance Liquid Chromatography. The stationary phase used was CI8 column and the mobile phase used is a binary system of acetonitrile-water (70:30). The system was detected using UV-Visible detector at the wavelength of 230 nm and flow rate of 1 mLmin-l . The analysis was carried out using simple analytical procedure which is solid liquid extraction (SLE) and the method was successful. The peak of chlorpyrifos appeared at retention time of 2.2 minutes. There were six samples that had been used including the blank. The linearity obtained was 0.9857. The concentration of chlorpyrifos in sample 1,2,3,4,5 and blank were 12.50 ppm, 8.73 ppm, 7.56 ppm, 5.21 ppm, 6.73 ppm and 4.34 ppm respectively. The removal percentages of chlorpyrifos in apples were ranging from 30% to 59%. The most effective washing solution was acetic acid with 58.32% removal and the least effective washing solution was tap water with 30.16% removal. The washing solution efficiencies depend on the concentration. The concentration of washing solution will enhance the solubility of chlorpyrifos in washing solution and lead to greater removal of chlorpyrifos.