Abstract:
Accumulation of pesticides in human body via food consumption poses health risks, hence the quantitative detection of pesticides in foodstuffs has become vital. In this study, a rapid and sensitive SERS-based sensor for detecting 2,4-dichlorophenoxyacetic acid (2,4-D) using antibody-functionalized magnetite nanoparticles (antibody-MNPs) as enrichment probe and antigen-MBA-functionalized hollow Au@Ag bimetallic nanoflowers (HAu@AgNFs@MBA-antigen) as SERS signal probe was developed. Under the optimized conditions, a wide linear range of 0.001−100 μg/mL for sensing 2,4-D was attained with a low detection limit (LOD) of 0.11 ng/mL. The developed sensor was successfully applied to detect 2,4-D in spiked tea and milk samples with recoveries of 89.73–100.27 % and the relative standard deviation (RSD) values of 2.56–4.97 % obtained. The SERS-based sensor fabricated when validated by the HPLC, no statistical significance differences were obtained based on their computed accuracy and precision values using the student's t- and F- tests at α = 5%.