Portable Detection of Malathion: Gold Nanoparticle-Based Colorimetric Aptasensor Coupled with Image Analysis Academic Article uri icon

abstract

  • Malathion is a commonly used organophosphate insecticide in agriculture, known for its effectiveness against a wide range of pests. However, the impact of its residues on the environment is a significant concern, with potential long-term effects on ecosystems, biodiversity, and human health. Therefore, on-site detection for monitoring its residues in the environment is crucial to ensure appropriate safety measures for usage. In this study, a rapid and simple colorimetric aptasensor that integrated with image analysis for malathion detection was explored. After adding malathion into a sensing solution (citrate-capped gold nanoparticles and a thiolated DNA aptamer), a visible color change can be observed within 15 seconds. Then, the color of the solution was captured by a smartphone and quantified to red, green, and blue (RGB) values. Under the optimum detection conditions, the developed aptasensor showed a good linear correlation between colorimetric response and MLT concentration (0.05 to 10.0 nM), with a low detection limit of 96 pM. The aptasensor showed excellent selectivity towards malathion in the presence of potential pesticides that could be present in the environment. Furthermore, the application of the aptasensor demonstrated successful in the detection of malathion in the spiked tap water samples, achieving satisfactory recovery rates (about 90 to 106%). These findings demonstrated that the proposed aptasensor provides a fast, sensitive and reliable detection of MLT, offering a promising tool for environmental detection of MLT.

publication date

  • 2025

number of pages

  • 18

start page

  • 33

end page

  • 51

volume

  • 33

issue

  • 1