Non-Enzymatic Electrochemical Sensing of Malathion Pesticide in Tomato and Apple Samples Based on Gold Nanoparticles-Chitosan-Ionic Liquid Hybrid Nanocomposite

Sensors (Basel). 2018 Mar 4;18(3):773. doi: 10.3390/s18030773.

Abstract

Malathion (MLT) is an organophosphorous type pesticide and having seriously high toxicity and electrochemical platforms for rapid, simple, inexpensive and sensitive determination of pesticides is still a special concern. This paper describes a simple preparation of a composite film consisting of ionic liquid (IL), chitosan (CS) and electrochemically synthesized gold nanoparticles (AuNPs) on single use pencil graphite electrodes (PGEs). The microscopic and electrochemical characterization of AuNP-CS-IL/PGE was studied using scanning electron microscopy, cyclic voltammetry and electrochemical impedance spectroscopy. This fabricated surface was then explored for the first time as a sensing matrix for the non-enzymatic electrochemical sensing of malathion by cyclic voltammetry and square wave voltammetry measurements. The proposed AuNP-CS-IL/PGE showed excellent characteristics and possessed remarkable affinity for malathion. The voltammetric current response exhibited two linear dynamic ranges, 0.89-5.94 nM and 5.94-44.6 nM reflecting two binding sites, with a detection limit of 0.68 nM. The method was applied in real sample analysis of apple and tomato. The results demonstrate the feasibility of AuNP-CS-IL-modified electrodes for simple, fast, ultrasensitive and inexpensive detection of MLT.

Keywords: direct electrochemical detection; electrochemical sensor; food safety; gold nanoparticles; ionic liquids; malathion; organophosphorus (OP) pesticides.

MeSH terms

  • Biosensing Techniques
  • Chitosan
  • Electrochemical Techniques
  • Electrodes
  • Gold
  • Graphite
  • Ionic Liquids
  • Lycopersicon esculentum*
  • Malathion
  • Malus*
  • Metal Nanoparticles
  • Nanocomposites
  • Pesticides

Substances

  • Ionic Liquids
  • Pesticides
  • Gold
  • Graphite
  • Chitosan
  • Malathion