Contrastive Study of In Situ Sensing and Swabbing Detection Based on SERS-Active Gold Nanobush–PDMS Hybrid Film

Abstract

Surface-enhanced Raman scattering (SERS) with fast and intuitive property has been extensively utilized in the field of food safety. Here, we demonstrated a novel noble metal–polymer hybrid film as a SERS substrate for food fungicide analysis. Benefiting from its transparency and flexibility, poly­(dimethylsiloxane) (PDMS) film was chosen as a versatile supporting matrix to grow gold nanobushes (Au NBs) through a seed-mediated process. The as-prepared AuNB–PDMS hybrid film performed satisfactorily in testing 4-nitrothiophenol (4NTP) and exhibited an enhancement factor (EF) of 2.56 × 106. Moreover, the high sensitivity and elastic properties make the hybrid film a promising substrate in practical detection. Hence, the in situ sensing of TBZ, carbaryl, and their mixture was finally realized using the developed hybrid film, which exhibited higher sensitivity than that obtained by the swabbing method. This high-performance SERS substrate based on the flexible and transparent AuNB–PDMS hybrid film has great potential applications in the fast in situ monitoring of biochemical molecules.

Fabrication and Comparative Quantitative Analysis of Plasmonic-Polymer Nanocomposites as Optical Platforms

“…Plasmonic NPs are incorporated into polymer matrices to design more user-friendly, highly robust, and flexible optical platforms while preserving the optical properties of plasmonic NPs. A wide range of plasmonic-polymer nanocomposites has been developed by combining AuNPs or AgNPs and polymers such as agarose, chitosan, and poly­(methyl methacrylate) (PMMA) for SERS-based optical sensing, imaging, and photothermal applications. ,− Plasmonic-polymer nanocomposites can synergistically benefit from the excellent optical properties of plasmonic NPs and the wide range of mechanical and chemical properties of polymers, rendering various functionalities. , For instance, plasmonic nanocomposites of macroporous poly- N -isopropylacrylamide (pNIPAM) hydrogel loaded with gold nanorods have been used as biocompatible, SERS substrates for label-free in situ probing of quorum sensing in biofilms . Chitosan complexed with plasmonic NPs have been widely used as biocompatible optical substrates due to their excellent biocompatibility, biodegradability, and non-toxicity. ,,− Xu et al .…”

3D Flexible SERS Substrates Integrated with a Portable Raman Analyzer and Wireless Communication for Point-of-Care Application

“…From these results, it can be observed that the as-prepared flexible SERS substrates exhibit outstanding uniformity and excellent reproducibility. Moreover, comparisons of the limits of detection, enhancement factors and signal reproducibilities between the Ag NPs@W-PDMS SERS substrate and other flexible SERS substrates are shown in Table S1, indicating that the Ag NPs@W-PDMS SERS substrate has excellent performance featuring a large enhancement factor, large-scale uniformity, and excellent spectral reproducibility. − …”

Construction of Reusable PMMA–Ag/g-C3N4/Ag Hybrid Substrates with Plasmonic-Enhanced Intrinsic Raman Signals for Quantitative SERS Detection and Green Degradation

“…Such values are lower than the thresholds of TBZ (20 μg/mL) and CA (100 mg/kg) in national regulations. 62,63 Meanwhile, such quantitative and sensitive SERS detections of 58 assembling gold nanorods 0.991 216 ng/mL 50−1000 ng/mL lemon juice SERS 59 Fe 3 O 4 @GO@Ag 0.962 40 ng/cm 2 4 ng/cm 2 −40 μg/cm 2 fruit peels SERS 61 Ag-Au-IP6-Mil-101(Fe) 0.986 50 ng/mL 1.5−75 ppm juice sample SERS 64 Au NBs−PDMS hybrid film 0.98 0.64 ng/mL 10 −4 −10 −9 g/mL cherry HPCL 65 hydroxyl TBZ and CA were evaluated by comparing them with some previous reports. As illustrated in Tables 1 and 2, this work gave out better values of R 2 and LODs than other investigations and it can be peculiarly applied to deeply processed foods by straightforward wiping.…”