ANALYST
·
2023
·Vol. 148
·期 5
·1024-1031
·
IF 4.2
Xueyi Zhu,Ning Ma,Yizhen Wan,Lu Wang,Yu Zhang,Chengyu Yan,Weiping Qian
Immobilizing ligands is a crucial part of preparing optical sensors and directly connected to the sensitivity, stability, and other characteristics of sensors. In this work, an ordered porous layer interferometry (OPLI) system that can monitor the covalent coupling process of ligands in real time was developed. Films of silica colloidal crystal (SCC), as optical interference substrates, were surface modified by three different reagents: chloroacetic acid, glutaric anhydride, and carboxymethyl dextran. Staphylococcus aureus protein A (SPA), the ligand, was immobilized on SCC films. The covalent coupling process of SPA and SCC films can be dynamically monitored by the OPLI system. In addition, the three different strategies were evaluated by comparing the efficiency of the sensors prepared by different methods for binding Immunoglobulin G (IgG). The glutaric anhydride-modified sensor offers apparent advantages in terms of bound IgG quantity and affinity. This system provides a simple and intuitive way to determine the efficiency of different covalent coupling strategies. Furthermore, the sensor covalently coupled with SPA also excels in the determination of IgG content in complex systems such as milk. At the same time, the covalent coupling gives the sensor the ability to be stored stably over time.
研究领域:
材料科学
·
分析化学
·
光学传感
·
表面化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Yumei Chen,Jialin Zhang,RuiRui Liu,Ying Zhang,Jingming Zhou,Hongliang Liu,Yankai Liu,Ke Yan,Yanhua Qi,Enping Liu,Xifang Zhu,Aiping Wang
A label-free electrochemical immunosensor was developed to rapidly detect tilmicosin (TMC) residues in pork and milk. The immunosensor was constructed by immobilizing a high-affinity monoclonal antibody against TMC on an rGO-PEI-Ag nanocomposite-modified electrode. The rGO-PEI-Ag nanocomposites were prepared by mixing polyethyleneimine (PEI) modified reduced graphene oxide (rGO) with AgNO 3 solution. The prepared rGO-PEI-Ag nanocomposites showed good redox activity and conductivity, as characterized by ultraviolet-visible spectroscopy (UV–Vis), transmission electron microscopy (TEM), and X-ray diffraction (XRD). During the preparation process, staphylococcal protein A (SPA) was added to targetedly bind the Fc segment of the monoclonal antibody. The immunosensor showed a low detection limit (LOD) of 0.0013 ng/mL, a linear range of 0.01–100 ng/mL, and recoveries ranging from 92.77 to 100.02% in pork and 92.26–101.23% in milk. Furthermore, the immunosensor exhibited good stability, reproducibility, and specificity in detecting TMC in pork and milk real samples.
研究领域:
分析化学
·
食品科学
·
纳米技术
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Tianxiao Yu,Shikuan Hou,Xizhenzi Fan,Yanxia Qiao,Guohua Zhang,Lingli Wang,Jun Ge
In this work, an enzyme-free electrochemical immunosensor based on metal-organic framework (MOF) and single-wall carbon nanotube (SWCN) nanocomposite coated glassy carbon electrode (GCE) for rapid and sensitive detection of fibroblast growth factor 21 (FGF-21) was proposed. The synthesized MOF/SWCN were characterized by transmission electron microscopy (TEM). It exhibited high-speed charge mobility, excellent conductivity and high surface area, significantly amplifying the current signal response. Furthermore, to immobilize the FGF-21 capture antibody on the MOF/SWCN electrode surface in an ordered orientation, staphylococcal protein A (SPA) was introduced as a connecting element, which significantly increased the antigen-binding ability and immunosensor stability. Under optimal conditions, the wide linear range of the immunosensor was 1.00 pg mL -1 to 500 ng mL -1 , with a low detection limit was 0.35 pg mL -1 . Additionally, the immunosensor also showed excellent reproducibility and selectivity. It was also successfully used to detect FGF-21 in human serum samples with satisfying recoveries. Thus, the strategy provides a simple and sensitive method for FGF-21 detection, indicating significant potential applications in clinical diagnostics.
研究领域:
电化学
·
纳米技术
·
生物传感器
·
临床诊断
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
BIOELECTROCHEMISTRY
·
2023
·
IF 5
Wenjing Qian,Jingming Zhou,Yumei Chen,Hongliang Liu,Peiyang Ding,Yankai Liu,Chao Liang,Xifang Zhu,Ying Zhang,Enping Liu,Aiping Wang,Gaiping Zhang
Virginiamycin (VIR), a feed additive, is used to promote pig and poultry growth. However, it is hazardous to human health. This work described a label-free electrochemical immunosensor based on silver nanoparticles-reduced graphene oxide (AgNPs-rGO) nanocomposites and staphylococcal protein A (SPA) for the first time to directly detect the residual marker VIR M1. Good catalytic currents for oxygen reduction reaction were apparently obtained after the modification of nanocomposites on gold electrode. Nanocomposites were characterized using UV–Vis, X-ray diffraction (XRD) patterns, Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). SPA was targeted to immobilize VIR M1 monoclonal antibody (mAb) by binding to Fc region of antibody. The proposed immunosensor showed a wide linear range from 0.25 ng mL −1 to 100 ng mL −1 , providing detection limit (LOD) of 0.18 ng mL −1 of VIR M1. Recovery rates ranged from 92.27% to 98.84%, and relative standard deviation (RSD) was not above 6.6%, indicating the immunosensor could detect VIR M1 in actual samples with high accuracy. The sensor showed good selectivity, reproducibility and stability and could be considered as a potential tool for detection of VIR M1 in feed and animal derived food.
研究领域:
分析化学
·
电化学
·
生物传感器
·
食品安全
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）