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The increased demand for agricultural productivity to support the growing population has resulted in the expanded use of pesticides. However, modern pesticide applications contaminate air, water, soil, and unintentional target species. It is necessary to develop effective and sustainable methods to detect different pesticides within our environment. Surface-enhanced Raman spectroscopy (SERS) has garnered significant attention for its ability to detect and quantify environmental contaminants, as it is a rapid and sensitive technique that requires minimal sample preparation. The present study demonstrates the development of a biowaste-derived nanocellulose-based thin-film that, when integrated with gold nanoparticles, produces a sustainable and reproducible SERS nanosubstrate. In this study, three pesticides (carbaryl, ferbam, and thiabendazole) were sensitively and selectively detected by the combined use of this novel nanocellulose-based SERS nanosubstrate and a portable Raman instrument. The limits of detection were determined to be 1.34, 1.01, and 1.41 mg/L for carbaryl, ferbam, and thiabendazole, respectively, all of which are well below the agricultural application concentrations recommended. SERS signals were collected for both prepared ferbam spray solution and collected sprayed droplets, and it was found that there is no major difference in the signals, indicating that this detection method is reliable to detect pesticide droplets. A commercial pesticide was detectable by the biowaste-derived SERS nanosubstrate. This study is among the first to utilize biowaste-derived nanocellulose to create SERS nanosubstrate for pesticide detection in spray droplets. We demonstrate the high potential of biowaste-derived nanocellulose in combination with the portable Raman technique for agricultural pesticide spray detection.
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Facile synthesis of gold nanostars for the duplex detection of pesticide residues in grapes using SERS
AbstractIn recent years, concerns have been raised regarding the contamination of grapes with pesticide residues. As consumer demand for safer food products grows, regular monitoring of pesticide residues in food has become essential. This study sought to develop a rapid and sensitive technique for detecting two specific pesticides (phosmet and paraquat) present on the grape surface using the surface‐enhanced Raman spectroscopy (SERS) method. Gold nanostars (AuNS) particles were synthesized, featuring spiky tips that act as hot spots for localized surface plasmon resonance, thereby enhancing Raman signals. Additionally, the roughened surface of AuNS increases the surface area, resulting in improved interactions between the substrate and analyte molecules. Prominent Raman peaks of mixed contaminants were acquired and used to characterize and quantify the pesticides. It was observed that the SERS intensity of the Raman peaks changed in proportion to the concentration ratio of phosmet and paraquat. Moreover, AuNS exhibited superior SERS enhancement compared to gold nanoparticles. The results demonstrate that the lowest detectable concentration for both pesticides on grape surfaces is 0.5 mg/kg. These findings suggest that SERS coupled with AuNS constitutes a practical and promising approach for detecting and quantifying trace contaminants in food. Practical ApplicationThis research established a novel surface‐enhanced Raman spectroscopy (SERS) method coupled with a simplified extraction protocol and gold nanostar substrates to detect trace levels of pesticides in fresh produce. The detection limits meet the maximum residue limits set by the EPA. This substrate has great potential for rapid measurements of chemical contaminants in foods.
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- Award ID(s):
- 2103025
- PAR ID:
- 10500049
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Food Science
- Volume:
- 89
- Issue:
- 4
- ISSN:
- 0022-1147
- Format(s):
- Medium: X Size: p. 2512-2521
- Size(s):
- p. 2512-2521
- Sponsoring Org:
- National Science Foundation
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