Highly efficient catalytic hydrogen bond organic frameworks (HOFs)@HRP integrated with bowl-shaped organic SERS substrates for ultrasensitive detection of BPS.

With the growing public concern over environment and food safety, the detection of trace amounts of bisphenols S (BPS) becomes crucial. In this work, an ultrasensitive surface-enhanced Raman scattering (SERS) biosensor was developed based on hydrogen-bonded organic frameworks@horseradish peroxidase (HOFs@HRP) and hollow bowl-shaped SERS substrates (AFRNBs@AuNPs) for the detection of BPS. Due to the excellent biocompatibility and mild synthesis conditions, HOFs had been utilized as protective matrices for HRP, effectively preserving its enzymatic activity. Furthermore, hollow bowl-like morphology AFRNBs@AuNPs were successfully prepared as efficient SERS substrate. When BPS was present, the stronger affinity between BPS and its aptamer triggered a displacement reaction, allowing HOFs@HRP to bind with AFRNBs@AuNPs, thereby enabling the catalytic conversion of TMB into oxTMB and generating a detectable Raman signal. Accordingly, the biosensor exhibited a detection limit of 1.28 × 10-12 M. This method pioneers a new approach for trace BPS detection, demonstrating broad application prospects.