Synthesis of bimetallic core-shelled nanoparticles modified by 2-mercaptoethanol as SERS substrates for detecting ferbam and thiabendazole in apple puree

ABSTRACT

Modification of surface-enhanced Raman spectroscopy (SERS) substrates with thiol ligands is an emerging approach in enhancing the stability and sensitivity of metal substrates due to their good affinity with metals such as Au, Ag, and Cu. Thus, in the current study, 2-mercaptoethanol was used to modify the surface of silver-coated gold nanoparticles to develop a novel SERS substrate for the rapid assessment of fungicide residues in fruit samples. Results showed that the substrate could achieve the detection of ferbam and thiabendazole residues in apple puree with limits of detection of approximately 0.0042 and 0.0064 ppm, high coefficients of determination of 0.9946 and 0.9968, good recoveries ranging from 80 to 105 and 81 to 107% and relative standard deviations of 3.5–7.5 and 3.8–7.9 %, respectively. Therefore, the substrate developed could potentially be utilised to assess other toxic agrochemicals in future.

GRAPHICAL ABSTRACT

KEYWORDS:

• SERS substrate
• Raman
• fungicides
• residues detection
• fruit
• nanoparticles

Acknowledgments

The authors are grateful to the National Key R&D Program of China (2018YFC1603400) for its support. This research was also supported by the Guangdong Basic and Applied Basic Research Foundation (2020A1515010936), the Fundamental Research Funds for the Central Universities (D2190450), the Contemporary International Collaborative Research Centre of Guangdong Province on Food Innovative Processing and Intelligent Control (2019A050519001) and the Common Technical Innovation Team of Guangdong Province on Preservation and Logistics of Agricultural Products (2020KJ145). In addition, Nisar Hussain is in receipt of a PhD scholarship (201712800026) from the China Scholarship Council.