Ultrasensitive Determination of Thiabendazole in Fruit Juice by Surface-Enhanced Raman Scattering (SERS) Using a Covalent Organic Framework (COF) Gold Nanoparticle (Au NP) Substrate

Abstract

An effective and sensitive SERS substrate (TPDH-COF/Au NPs) on a covalent organic framework (TPDH-COF) decorated with gold nanoparticles (Au NPs) was fabricated via electrostatic self-assembly and successfully applied for the determination of thiabendazole (TBZ) in fruit juice. The “raspberry-like” structure SERS substrate combined the properties of the abundant “hot spots” between the Au NPs and the adsorption performance of TPDH-COFs for trace analytes. Excellent SERS performance was observed, which achieved a high enhancement factor value of 2.01 × 10⁸ for rhodamine 6 G, with considerable reproducibility and excellent long-term stability of at least 28 d. The limit of detection was estimated to be 5 ppb for TBZ in fruit juice. The result demonstrated that the TPDH-COF/Au NPs have great potential for SERS analyses and determination of pesticide residues in foods.

Keywords:

• Covalent organic framework (COF)
• fruit juice
• gold nanoparticles (Au NPs)
• surface-enhanced Raman scattering (SERS)
• thiabendazole

Data availability statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.

Disclosure statement

No conflicts of interest are reported by the authors.

Additional information

Funding

This work was supported by the Natural Science Foundation of Xinjiang Uygur Autonomous Region [2020D01C032] and the National Natural Science Foundation of China [No. 21565024].