In situ synthesized highly sensitive AANS@ZIF-8@GZEF constructed flexible SERS sensor for CPS determination

Aiming to meet the demand for rapid detection of chlorpyrifos (CPS), a surface-enhanced Raman scattering (SERS) sensor based on a gluten/zein electrospun film (GZEF) was fabricated via electrospraying. The SERS performance was namely improved through metal nanoparticles selection and optimization of loading amounts. Further construction of the AANS@ZIF-8@GZEF sensor was achieved through in-situ growth. Owning to the porous structure of ZIF-8, the trapping ability and enrichment effect of the SERS sensor were enhanced, resulting in a superior SERS enhancement effect of 1.58 times. Moreover, the CPS detection under various concentrations was carried out using the AANS@ZIF-8@GZEF sensor. The concentration-logarithm peak intensity equations were fitted, and the limit of detection (LOD) of CPS was calculated to be 0.981 μg/L. Finally, the detection of CPS residues on the peel of apples was performed using the AANS@ZIF-8@GZEF sensor, and the results showed that the overall recovery rate ranged between 91.18% and 96.83%, with all relative standard deviations being less than 5%. Great potential applications in the rapid and sensitive detection of chlorpyrifos in food are expected for the AANS@ZIF-8@GZEF sensor constructed in this study.