SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2021
·
IF 4.098
Lei Jin,Shufang Wang,Qing Shao,Yiyu Cheng
Salmonella should be absence in pharmaceutical preparations and foods according to regulations in many countries. Up to now, rapidly detecting Salmonella at 1 CFU·[10 g (mL) ] −1 in pharmaceutical preparation or 1 CFU·[25 g (mL) ] −1 in food samples is still a challenge. Herein, we present an aptamer-based surface-enhanced Raman spectroscopy (SERS) method for rapidly detecting Salmonella Enteritidis by using a handheld Raman instrument. The aptamer could specifically recognize S. Enteritidis, and 4-MBA self-assembled on the surface of [email protected] NPs was used as a Raman reporter molecule. The method was validated to be high specific with no interference from other five pathogenic bacteria. It could identify S. Enteritidis contaminant at ∼ 1 CFU·(10 g) −1 spiked level in a real sample (Wenxin granule, a botanical drug) after 6 h of enrichment. The detection time was much shorter than that of the methods (more than 54 ∼ 96 h) in the standards of pharmaceutical preparations and foods. In addition, the method could quantitatively determinate S. Enteritidis with satisfactory results. The SERS peak intensities of 4-MBA at 1072 cm −1 showed a good linear correlation (R 2 = 0.9873) with the logarithms of S. Enteritidis concentrations ranging from 4.17 × 10 2 to 1.39 × 10 7 CFU·mL −1 . T-test result (P = 0.425) revealed that there was no significant difference between the determination results obtained by the SERS method and the plate counting method. Therefore, the study indicated that the method was practical and reliable, and it could be a promising alternative for the on-site detection of S. Enteritidis.
研究领域:
分析化学
·
食品科学
·
药学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS
·
2024
·Vol. 24
·期 12
·3809
·
IF 3.4
Feng Chen,Mingfu Zhao,Bin Zhang,Minggang Zhao,Ye Ma
Copper ion (Cu2+) pollution poses a serious threat to marine ecology and fisheries. However, the complexity of seawater and its interference factors make the online detection of Cu2+quite challenging. To address this issue, we introduce the concept of the photo-assisted adjustment barrier effect into electrochemical detection, using it as a driving force to generate electrochemical responses. The Schottky barrier demonstrates a remarkable regulatory influence on the electrochemical response under photoexcitation, facilitating the response through Cu2+adsorption. We developed a 4-MBA-AuNPs/CdS/FTO composite that serves as a sensitive platform for Cu2+detection, achieving a detection limit of 70 nM. Notably, the photo-assisted adjustment of the barrier effect effectively counters the interference posed by ions in seawater, ensuring accurate detection. Furthermore, the sensor exhibits a promising recovery rate (99.62–104.9%) in real seawater samples, highlighting its practical applications. This innovative approach utilizing the photo-assisted adjustment barrier effect offers a promising path for developing electrochemical sensors that can withstand interference.
研究领域:
环境科学
·
分析化学
·
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Leyi Fang,Xiao-Tong Pan,Kang Liu,Dechen Jiang,Deju Ye,Li-Na Ji,Kang Wang,Xing-Hua Xia
The simultaneous and accurate detection of intracellular pH (pHi) and extracellular pH (pHe) is essential for studying the complex physiological activities of cancer cells and exploring pH-related therapeutic mechanisms. Here, we developed a super-long silver nanowire-based surface-enhanced Raman scattering (SERS) detection strategy for simultaneous sensing of pHi and pHe. A surface-roughened silver nanowire (AgNW) with a high aspect ratio is prepared at a nanoelectrode tip using a Cu-mediated oxidation process, which is then modified by pH-sensitive 4-mercaptobenzoic acid (4-MBA) to form 4-MBA@AgNW as a pH sensing probe. With the assistance of a 4D microcontroller, 4-MBA@AgNW is efficient in simultaneously detecting pHi and pHe in both 2D and 3D culture cancer cells by SERS, with minimal invasiveness, high sensitivity, and spatial resolution. Further investigation proves that the surface-roughened single AgNW can also be used in monitoring the dynamic variation of pHi and pHe of cancer cells upon stimulation with anticancer drugs or under a hypoxic environment.
研究领域:
纳米技术
·
生物医学工程
·
癌症研究
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CONTROL
·
2024
·
IF 5.6
Xiangyu Song,Huhu Wang,Xuefei Shao,Xiaobo Yu,Xinglian Xu
Salmonella Typhimurium is the prevalent pathogenic bacterium that causes foodborne-related diseases. Here, we developed a surface-enhanced Raman scattering (SERS) biosensor for S . Typhimurium detection. The biosensor was based on Au@Ag core-shell nanorods (Au@Ag NRs) to enhance Raman signal and aptamer-specific identification. 4-mercaptobenzoic acid (4-MBA) and aptamer-modified Au@Ag NRs were used as Raman signal probes. The aptamer adsorbed on the Au@Ag NRs surface when the reaction system was free of bacteria. Once S . Typhimurium was added, the aptamer then specifically identified and captured the cells. The decrease of free aptamers in solution restoring the SERS “hot spot” between the Au@Ag NRs and enhancing the 4-mercaptobenzoic acid (4-MBA) Raman signal. Quantitative analysis of S . Typhimurium was performed using Raman-enhanced spectroscopy. Under optimised conditions, the 4-MBA SERS intensity at 1072 cm −1 was used to determine S . Typhimurium in the range of 10 2 –10 7 CFU mL −1 (y = 1660.84x+2340.7, R 2 = 0.9912). The limit of detection was 64 CFU mL −1 . This method also has high specificity and is not interfered by the other five control bacteria to complete the detection of S . Typhimurium. The developed method is simple, rapid, sensitive and specificity, which can be used to detect actual samples. It can be potentially used for detecting bacteria.
研究领域:
纳米技术
·
分析化学
·
生物传感器
·
食品安全
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
Materials Chemistry Frontiers
·
2023
·Vol. 7
·期 6
·1100-1109
·
IF 7
Suyang Li,Junjie Chen,Wanbing Xu,Biao Sun,Jiechen Wu,Qiang Chen,Pei Liang
Bimetallic gold core–silver shell (Au@Ag) surface-enhanced Raman scattering tags draw broad interest in the fields of biological and environmental analyses. Herein, an efficient hybrid microfluidic chip was designed to prepare uniform Au@Ag core–shell nanoparticles, and DTNB was used as the internal standard tag molecule to prepare Au@DTNB@Ag for SERS detection. Homogeneous core–shell nanoparticles with a particle size of 90 nm were prepared by mixing a silver precursor and a gold core in a microfluidic chip. The relative standard deviation (RSD) of the particle size distribution was close to 10%, and the detection limit of 4-MBA was as low as 10-10 M. In order to solve the influence of SERS signal fluctuation, a uniform Au@DTNB@Ag core–molecule–shell structure was synthesized in a microfluidic chip, and the characteristic peak of the analyte was corrected by the relative intensity of the DTNB characteristic peak (1335 cm−1). The experimental results showed that the SERS detection was achieved with high reproducibility, and the SERS peak intensity had a good linear correlation with the concentration. The homogeneous SERS substrate prepared using a microfluidic chip has potential for sensitive and reliable detection of environmental chemical contaminants.
研究领域:
纳米技术
·
分析化学
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子