Functionalized hollow Au@Ag nanoflower SERS matrix for pesticide sensing in food

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 mu g/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 alpha = 5%.