Sensitive determination of Patulin by aptamer functionalized magnetic surface enhanced Raman spectroscopy (SERS) sensor

Food pollution caused by Patulin (PAT) seriously threatens the safety of human diets and has attracted extensive attention. Early and accurate detections of PAT are essential to prevent further toxin spreading and contamination. A surface enhanced Raman scattering (SERS) aptasensor was fabricated by combining a gold-silver core shell structure containing signal molecule (ADANRs) and chitosan modified magnetic nanoparticles (CS-Fe3O4). The modified ADANRs with the complementary chain of the aptamer (SH-cDNA-ADANRs) which were served as the signal probes and the aptamer modified CS-Fe3O4 (NH2-apt-CS-Fe3O4) were served as the capture probes. In addition to the ability to recognize the target PAT, the capture probe also showed a strong enrichment ability under the action of external magnetic force. The intraparticle plasma coupling between the inner gold core and the outer silver shell can greatly improve the SERS activity of the signal molecules. SERS aptasensor was used to collect the spectra of actual apple samples spiked with different PAT content. The minimum detection limit of SERS aptasensor for detecting PAT in actual samples was 0.0384 ng/mL and the recovery rate range was from 96.3% to 108%. In conclusion, the sensitive and specific SERS aptasensor detection of PAT based on aptamer functionalized nanoparticles exhibited great potential for practical application in mycotoxin detection and analysis.