Abstract
Background: 2-Methylisoborneol (2-MIB) and geosmin (GSM) are algal metabolites causing earthy/musty odors in aquaculture, leading to economic losses. Traditional analytical methods have limitations such as time consumption, complex operation, insufficient sensitivity, and difficulty in on-site application. To address these limitations, we developed a surface-enhanced Raman scattering (SERS) platform using a stainless steel wire-graphene-Au@Ag hollow nanoshells-polydimethylsiloxane (SSW-G-Au@Ag HNSs-PDMS) probe for the ultrasensitive detection of 2-MIB and GSM.
Results: Au@Ag HNSs serve as high-performance SERS substrates, amplifying Raman signals via strong localized surface plasmon resonance, while G further enhances sensitivity through π-π stacking and charge transfer. The SSW provides structural rigidity, and the PDMS coating ensures stability, improving detection reproducibility. This method achieves a wide linear detection range (1 ng L-1–1 mg L-1) and ultralow detection limits (0.25 ng L-1 for 2-MIB, 0.38 ng L-1 for GSM), demonstrating exceptional sensitivity. The proposed method has been successfully applied to the detection of real aquaculture water, with GSM concentrations spanning 0.09–0.18 mg L-1 and 2-MIB levels ranging from 0.12–0.25 mg L-1, and the recovery of the SERS method (96.0% to 108.0% for GSM, 96.0% to 104.0% for 2-MIB) showed no significant difference compared with that of the GC-MS method (92.0% to 104.0% for GSM, 96.0% to 104.0% for 2-MIB). Compared to traditional techniques, this approach offers rapid, convenient, and interference-resistant detection.
Significance: This method utilizes portable sensing probes, which have a fast response and can achieve real-time monitoring. It has broad application prospects in food safety monitoring and water quality control.