A Film-Like Sers Aptasensor for Sensitive Detection of Patulin Based on Go@Au Nanosheets

Abstract

Patulin (PAT) commonly contaminates fruits, posing a significant risk to human health. Therefore, a highly effective and sensitive approach in identifying PAT is warranted. Herein, a SERS aptasensor was constructed based on a two-dimensional film-like structure. GO@Au nanosheets modified with SH-cDNA were employed as capture probes, while core-shell Au@Ag nanoparticles modified with 4-MBA and SH-Apt were utilized as signal probes. Through the interaction of capture probes and signal probes, adjustable hotspots were formed, yielding a significant Raman signal. During sensing, the GO@Au-cDNA competitively binds to Au@AgNPs@MBA-Apt, resulting in an inverse relationship between PAT levels and SERS intensity. The acquired results exhibit linear responses to PAT within the range of 1–70 ng/mL, with a calculated limit of detection of 0.46 ng/mL. In addition, the SERS aptasensor exhibited satisfactory recoveries in apple samples, which aligned closely with HPLC. With high sensitivity and specificity, this method holds significant potential for PAT detection.

Keywords: Surface-enhanced Raman scattering (SERS), Patulin, aptasensor, Film-like GO@Au, Core-shell nanoparticles