3D MOF Photonic Microspheres for Thiram SERS Fingerprint Detection

The persistent migration of pesticides into aquatic ecosystems poses severe risks to environmental and public health. Monitoring pesticide residues along these migration pathways is therefore critical. Herein, we report the first application of a three-dimensional (3D) photonic microsphere surface-enhanced Raman spectroscopy (SERS) substrate (ZIF-8 PCMs-NH2@AuNPs) for the targeted adsorption and trace detection of the pesticide thiram. Synthesized via microfluidics, these hierarchically porous metal-organic framework microspheres overcome the poor reproducibility of conventional substrates by yielding highly uniform, stable "Raman hotspots" through surface-modified AuNPs. This structurally reproducible substrate achieved an enhancement factor of 8.4 × 107. For thiram analysis, it demonstrated a broad linear range (0.05-10 μg/mL) and a low limit of detection (0.0137 μg/mL). Validated in real water samples, this platform provides a robust analytical tool for monitoring pesticide residues of the migration pathways (soil water-river water-tap water).