A new ultrasonic triboelectric catalytic amplification strategy for SERS determination of trace nonylphenol in milk with dual nanosurface COF probes

Two new nanosurface molecularly imprinted covalent organic framework nanoprobes (MICOF) with recognition and catalytic amplification di-functions for the detection of trace endocrine disruptor nonylphenol (NPN) in milk were synthesized, gold nanocluster (AuNC)/nanopolyvinylchloride (PVC) as substrates, NPN as the template molecule, benzidine and 2,4,6-triformylphloroglucinol as the functional monomers. The di-nanoprobes efficiently catalyzed a new indicator nanoreaction between HAuCl 4 and triethanolamine to generate gold nanoparticles (AuNPs) with SERS effect. Surprisingly, under ultrasonic irradiation, the di-nanoprobes exhibited extremely strong catalysis, due to the triboelectric nanogenerator (TENG) constructed. The AuNC@COF was positive and the PVC@COF was negative, with an increase in catalytic activity of 680%. When NPN was added, it was selectively adsorbed in the nanoprobe imprinted sites, further enhancing catalysis. The working curve slope was increased by 2000%, with a linear range of 0.2-10 nmol/L and limit of detection (LOD) was 0.060 nmol/L NPN. The method was applied to the determination of milk with relative deviations (RSD) of 0.97-9.6% and recovery of 90.4-109.8%. In addition, this new SERS quantitative analysis method was also used to determine phenol, bisphenol A and 1-naphthol with LOD were 0.080, 0.060 and 0.12 nmol/L respectively, which proved that it is of universality and high sensitivity. The ultrasonic driven MICOF di-probe TENG catalytic enhancement mechanism was constructed.