Jingyi Fan, Yiqun Huang, Junjian Miao, Keqiang Lai
{"title":"Temperature-responsive AuNPs/poly(N-isopropylacrylamide) hydrogel-based sensor for SERS detection of paraquat in fruit juices","authors":"Jingyi Fan, Yiqun Huang, Junjian Miao, Keqiang Lai","doi":"10.1007/s00604-025-07366-9","DOIUrl":null,"url":null,"abstract":"<div><p> A novel composite SERS substrate was developed based on gold nanoparticles (AuNPs) and poly(N-isopropylacrylamide) (PNIPAM) hydrogel. PNIPAM hydrogel is a temperature-responsive material with a lower critical solution temperature (LCST) of about 32 °C, regulating its swelling–shrinking behavior by changing temperature to evaluate the enrichment efficiency of target molecules. Experimental results demonstrated that the substrate exhibited a swelling ratio of 400–600% at room temperature, facilitating the efficient enrichment of paraquat molecules. The optimal Raman response was observed when the substrate contained a NIPAM concentration of 0.8 mol/L and an AuNPs concentration of 300%. Additionally, the substrate exhibited excellent detection performance, including high sensitivity, good reproducibility, uniformity, and temporal stability. The minimum detectable concentration of paraquat in standard solutions was 0.1 μg/L. In apple juice and orange juice, the detection limit ranged from 0.072 to 0.112 μg/L, with spiked recoveries of 85.55%-110.55% and 88.57%-107.15%, respectively. This study presents a highly selective and reliable SERS sensing strategy for the rapid detection of trace paraquat in juice samples.</p><h3>Graphical Abstract</h3>\n<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":705,"journal":{"name":"Microchimica Acta","volume":"192 8","pages":""},"PeriodicalIF":5.3000,"publicationDate":"2025-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Microchimica Acta","FirstCategoryId":"92","ListUrlMain":"https://link.springer.com/article/10.1007/s00604-025-07366-9","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, ANALYTICAL","Score":null,"Total":0}
引用次数: 0
Abstract
A novel composite SERS substrate was developed based on gold nanoparticles (AuNPs) and poly(N-isopropylacrylamide) (PNIPAM) hydrogel. PNIPAM hydrogel is a temperature-responsive material with a lower critical solution temperature (LCST) of about 32 °C, regulating its swelling–shrinking behavior by changing temperature to evaluate the enrichment efficiency of target molecules. Experimental results demonstrated that the substrate exhibited a swelling ratio of 400–600% at room temperature, facilitating the efficient enrichment of paraquat molecules. The optimal Raman response was observed when the substrate contained a NIPAM concentration of 0.8 mol/L and an AuNPs concentration of 300%. Additionally, the substrate exhibited excellent detection performance, including high sensitivity, good reproducibility, uniformity, and temporal stability. The minimum detectable concentration of paraquat in standard solutions was 0.1 μg/L. In apple juice and orange juice, the detection limit ranged from 0.072 to 0.112 μg/L, with spiked recoveries of 85.55%-110.55% and 88.57%-107.15%, respectively. This study presents a highly selective and reliable SERS sensing strategy for the rapid detection of trace paraquat in juice samples.
期刊介绍:
As a peer-reviewed journal for analytical sciences and technologies on the micro- and nanoscale, Microchimica Acta has established itself as a premier forum for truly novel approaches in chemical and biochemical analysis. Coverage includes methods and devices that provide expedient solutions to the most contemporary demands in this area. Examples are point-of-care technologies, wearable (bio)sensors, in-vivo-monitoring, micro/nanomotors and materials based on synthetic biology as well as biomedical imaging and targeting.