Multi-branch chemiluminescence–molecular imprinting sensor for sequential determination of carbofuran and omethoate in foodstuff

Abstract

A novel chemiluminescence-molecular imprinting (CL–MI) sensor was developed for the sequential determination of two pesticide residue components. One “X” shaped multi-branch flow cell was used to pack two kinds of molecularly imprinted microspheres (MIMs) as the recognition device. The MIMs were synthesized by precipitation polymerization with carbofuran and omethoate as templates, acrylamide as the functional monomer and ethylene glycol dimethacrylate as the cross-linker. The simple operation of the method enhanced the analysis efficiency and the combination of CL and MI resulted in good sensitivity and high selectivity. The application of the CL-MI sensor has very wide prospects. Calibration graphs were obtained over the concentration ranges 4.0 × 10⁻⁸ to 9.0 × 10⁻⁶ g mL⁻¹ and 1.0 × 10⁻⁷ to 9.0 × 10⁻⁶ g mL⁻¹ for carbofuran and omethoate, respectively. The limits of detection were 2.5 × 10⁻⁸ g mL⁻¹ for carbofuran and 4.2 × 10⁻⁸ g mL⁻¹ for omethoate. The proposed method was successfully applied to the sequential determination of both compounds in foodstuff.