Fe3O4-carboxyl modified AuNPs-chitosan@AgNPs as a robust surface-enhanced Raman scattering substrate for rapid analysis of tryptamine and ofloxacin in aquatic products

• Published in: Talanta (Oxford) 2024-01, Vol.266 (Pt 2), p.125057, Article 125057
• Main Authors: Hu, Wenyao, Xia, Ling, Hu, Yufei, Li, Gongke
• Format: Article
• Language: English
• Subjects: Aquatic product; Fe3O4–AuNCs–Cs@AgNPs; Magnetic substrate; Ofloxacin; Surface-enhanced Raman scattering; Tryptamine
• ISSN: 0039-9140; 1873-3573; 1873-3573
• DOI: 10.1016/j.talanta.2023.125057

Rapid and accurate quantification of trace targets in complex samples is an extremely challenging issue in fast analysis field. Herein, we developed Fe3O4-carboxyl modified AuNPs-chitosan@AgNPs composite (Fe3O4–AuNCs–Cs@AgNPs) as a robust surface-enhanced Raman scattering (SERS) substrate for rapid analysis of tryptamine (TPA) and ofloxacin (OFX). The substrate possessed abundant surficial active sites of –NH2, –OH and –COOH groups. The substrate exhibited good SERS activity for several different model molecules with enhancement factors (EFs) of 1.2 × 108 for 4-mercaptobenzoic acid. The substrate presented good stability for detection of TPA at pH 6.0 and OFX at pH 8.0, and relative standard deviations less than 5.0% for intra-batch and 6.0% for inter-batch. Also, the substrate possessed good time-stability within 50 days. The substrate integrated advantages of efficient enrichment, fast magnetic separation, and strong localized surface plasmon resonance properties of AgNPs. With versatile merits, TPA and OFX can be enriched and separated within 10 min. SERS methods for analysis of TPA and OFX were developed with detection limits of 35.5 μg/L and 15.8 μg/L, respectively. TPA and OFX were actually found in aquatic product, and recoveries during sample analysis were 89.3%–110% for TPA and 89.3%–96.8% for OFX. The analytical process completed within 30 min via enrichment-separation-detection all-in-one, exhibiting great potential for rapid analysis of toxic biogenic monoamines and antibiotic residues in food. The robust Fe3O4–AuNCs–Cs@AgNPs SERS substrate was developed for rapid analysis of tryptamine and ofloxacin in aquatic products via enrichment-separation-detection all-in-one strategy. [Display omitted] •The Fe3O4–AuNCs–Cs@AgNPs magnetic SERS substrate with abundant active sites of –NH2, –OH and –COOH prepared.•An enrichment-separation-detection all-in-one achieved by magnetic SERS substrate.•The substrate with selectivity to tryptamine among biogenic monoamines and ofloxacin among quinolones.•Rapid analysis of tryptamine and ofloxacin in aquatic products realized.