A facile heat-treatment solid phase microextraction method for SERS detection of isocarbophos in tea using a hand-held Raman spectrometer

• Published in: Food chemistry 2023-10, Vol.424, p.136397-136397, Article 136397
• Main Authors: Zhang, De, Wu, Zhuoqun, Cao, Minhui, Ni, Dejiang, Yu, Zhi, Liang, Pei
• Format: Article
• Language: English
• Subjects: Copper foam; Hot Temperature; Pesticide residues; Pesticides - analysis; Reduced graphene oxide; SERS; Solid Phase Microextraction - methods; Spectrum Analysis, Raman - methods; Tea - chemistry; Tea safety
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2023.136397

[Display omitted] •A facile sensor system based on HT-SPME and SERS was established.•The system can real-time test isocarbophos in tea without complex pretreatment.•Cu@rGO@AgNPs has powerful SERS enhancement and excellent adsorption properties.•The LOD of isocarbophos was as low as 0.00451 ppm.•The detection results of the system were consistent with those by GC–MS. A facile sensor system based on heat-treatment solid phase microextraction and Surface-Enhanced Raman Scattering (HT-SPME-SERS) was established for in-situ detection of isocarbophos in complex tea matrix. Starting from the action optimization of temperature control unit and air flow control unit, pesticide molecules volatilizing from solution are efficiently captured by substrate and generate real-time SERS signals by a hand-held Raman spectrometer, and the sensor system based on HT-SPME-SERS was finally established. A novel SERS substrate of Cu@rGO@Ag was developed as HT-SPME-SERS material, where reduced graphene oxide (rGO) enriched pesticide molecules by π-π stacking. A superior detection sensitivity brought by the ultra-high enhancement effect of Cu@rGO@Ag substrate was obtained. A good linear relationship between Raman intensity and isocarbophos concentration was obtained and the limit of detection (LOD) was as low as 0.00451 ppm. The detection results obtained from the sensor system have been verified by gas chromatography-mass spectrometer (GC–MS), showing its great application potential for the safety of agricultural products.