Degradation of Imidacloprid Residue in Cabbage (Brassica oleracea) Using Advanced Oxidation Processes and Its Analyzing by Spectrophotometer and HPLC

Abstract

Imidacloprid is a synthetic pesticide used to kill and control insects by cabbage farmers. Consuming cabbage contaminated with imidacloprid can cause health problems such as chronic kidney, reproductive disorders and cancer. The parameters for degradation of imidacloprid residue in cabbage were processing time (5, 10, 15, 20, and 25 min), water volume (50, 100, 150, and 200 mL), and sample mass (25, 50, 75, and 100 g). Degradation of imidacloprid residue in cabbage using Advanced Oxidation Processes (AOPs) methods such as ozonolysis, sonolysis, and sonozolysis were compared. Methods of ozonolysis, sonolysis, and sonozolysis have performed using an ozonicator (ozone dose: 400 mg h-1), sonicator (35 kHz), and a combination of both. Using spectrophotometers UV-Vis and High-Performance Liquid Chromatography (HPLC) measurements showed a decrease in imidacloprid concentration after degradation. The degradation percentage of the imidacloprid residue with ozonolysis was higher than that of sonolysis and sonozolysis. The percentage of imidacloprid degradation by ozonolysis in 50 g cabbage at 100 mL of water increased to 82.53% for 15 min. The HPLC chromatogram showed no new peaks that formed after degradation. The imidacloprid residue’s degradation kinetics were then investigated. For all AOPs methods, the kinetic analysis demonstrated that imidacloprid degradation fit within a first-order kinetic model. The kinetic data showed that ozonolysis degraded imidacloprid with a half-life (t1/2) of 15.22 min, shorter than sonolysis and sonozolysis.