In situ synthesis of low-cost and large-scale flexible metal nanoparticle–polymer composite films as highly sensitive SERS substrates for surface trace analysis

Abstract

In situ synthesis of low-cost and large-scale flexible metal nanoparticle-polymer composite films as highly sensitive SERS substrates for surface trace analysis † Surface-enhanced Raman spectroscopy (SERS) has been one of the most promising analytical tools.Despite many efforts in the design of SERS substrates, it remains a great challenge for creating a general flexible substrate that could in situ detect analytes on diverse objects. Herein, we report our attempt to address this issue by developing a facile and versatile method capable of generating silver/gold nanoparticles in situ on the surface of a cellulose acetate (CA) polymer in a simple, cheap, practical, and capping agent-free way. The as-prepared substrates exhibit excellent sensitivity, which enabled detection of Rhodamine 6G at concentrations as low as 10 À12 M. Taking advantage of the excellent flexibility and optical transparency of the CA matrix, the highly SERS-active substrate was applied for in situ identification and detection of pesticide residues on fruits. The results indicated that tetramethylthiuram disulfide (TMTD) and thiabendazole (TBZ) can be clearly identified at concentrations as low as 18.05 ng cm À2 and 15.1 ng cm À2 , respectively, which were much lower than the maximum permitted residue doses with respect to food safety.View Article Online the TBZ (a) and TMTD (b) powder, and (c) the mixture of 5 Â 10 À5 M TMTD and TBZ on the apple peel.2862 | RSC Adv., 2019,9,[2857][2858][2859][2860][2861][2862][2863][2864] This journal is

Cryogenic Sample Processing with Liquid Nitrogen for Effective and Efficient Monitoring of Pesticide Residues in Foods and Feeds

“…A literature search using Web of Science was conducted in April of 2019 to peruse the 200 most recent publications about pesticide residue analysis at the time. As before, a notable number of papers involved (bio)­sensors, , nanotechnology, − surface-enhanced Raman spectrometry (SERS), − and other microextraction techniques. A disproportionate number of publications entailed analysis of liquid samples (e.g., water, juices, and wine) rather than food or soil samples, undoubtedly in part as a result of the greater ease of sample processing and preparation of liquids versus solids.…”

Flexible Surface‐Enhanced Raman Scattering Substrates: A Review on Constructions, Applications, and Challenges

“…Besides, by modifying the cellulose surface with specific functional compounds, the metal sources such as AgNPs, AuNPs, or AuCl 4 − with negative charges can also be bonded to the surfaces of cellulose through electrostatic interactions. [ 49–51 ] Through whether electrostatic attraction or chemical reaction, the noble metal nanomaterials can be uniformly distributed on the surface of cellulose films. It is worth noting that the interaction of plasmonic nanomaterials with flexible film surfaces should be tenacious, otherwise the performance of the fabricated flexible SERS substrates would be weakened by the loss of noble metal nanostructures during the measurement process.…”

In Situ Collection and Rapid Detection of Pathogenic Bacteria Using a Flexible SERS Platform Combined with a Portable Raman Spectrometer

“…Typical SERS substrates are based on rigid substrates such as silicon and glass, which are not suitable for sample collection by physical wiping [20][21][22][23]. An enhanced substrate with good flexibility can maximize sample collection by wiping irregular surfaces, enabling in situ detection and broadening the application of SERS technology [24][25][26][27][28][29]. Flexible SERS substrates have attracted extensive attention from researchers [30].…”