Analytical Methods
·
2015
·Vol. 7
·期 6
·2391-2398
·
IF 1.821
Zhen Yang,Jian Lei,Xue-cheng Sun,Chong Lei,Yong Zhou,Yan Liu
Magnetic bead-based biosensors are becoming a hot spot in biomedical fields. A Dynabeads-labeled immunoassay has been developed using a micro fluxgate biosensor for the detection of alpha fetoprotein (AFP) and carcinoembryonic antigen (CEA). The micro fluxgate sensors with a rectangular permalloy core with sides of equal width and three-dimensional solenoid coils are fabricated by micro-electro-mechanical-system (MEMS) technology, including thick photoresist lithography and electroplating. The immune reaction of biomarkers is accomplished on a separated Au film substrate surface with a self-assembled layer. Sandwich immunoassay is used to specifically capture and label the biomarker. Dynabeads are conjugated into the biomarker by a streptavidin–biotin system. The micro fluxgate-based sensing system was characterized firstly in different concentrations of Dynabeads. It is found that a concentration as low as 0.1 μg ml−1 (90 Dynabeads) can be detected by this sensing system with an external magnetic field in the range of 643 μT to 1180 μT. The AFP and CEA with different concentrations were detected by the sensing system. The results reveal that a minimum detectable concentration of 1 pg ml−1 was achieved in the measuring ranges of 724 μT to 1150 μT for AFP, and 670 μT to 1110 μT for CEA. Compared with a micro fluxgate sensor with a ribbon core for the detection of biomarkers, the micro fluxgate sensor with an electroplated permalloy core possesses a wider linear measuring range, and could make it possible to integrate a micro fluxgate-based biosensing system produced on a large scale, with an expanded application field and reduced costs.
研究领域:
生物医学工程
·
分析化学
·
医学诊断
·
传感器技术
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2020
·
IF 2.463
Chulei Zhao,Ke Gao,Chaoyun Ma,Mei Wu,Kaihang Cao,Yuxiao Yang,Chenglin Hong,Xiuwen Qiao
A “label-free” electrochemical immunosensor was developed to detect α-fetoprotein (AFP) sensitively. HCS@PANI (High carbonized nanospheres@Polyaniline) is used as an electrochemical sensing platform to improve conductivity and enhanche the amount of AFP antibody (anti-AFP) immobilized on the electrode surface. PANI, which is involved by protonic acid, exhibits excellent electrochemical activity and can be used as a direct electron mediator to further amplify electrochemical signals. Under optimal conditions, the electrochemical immunosensor has a linear range of 0.001–80 ng/mL and a minimum detection limit of 0.33 pg/mL. The immunosensor is expected to be used in clinical laboratories to detect AFP and other tumor markers in human plasma for precancerous screening or cancer surveillance.
研究领域:
分析化学
·
生物化学
·
材料科学
·
医学诊断
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2022
·
IF 9.794
Leyi Yang,Guanbing Zhou,Yijie Jin,Yan Sun,Qiao Liu,Chongyi Chen
Developing hydrogel electrolytes combining enhanced ionic conductivity , great electrolyte/electrode interfacial contact and high electrochemical stability represents the basic demand of flexible electronic devices for cryogenic applications, but is still a formidable challenge at present. Herein, inspired by the antifreeze mechanism of antifreeze proteins (AFP), we developed a facile spatially confined strategy to stabilize water in molecular level so as to prevent freezing meanwhile maintain other critical features of hydrogels at subzero temperature. Meriting from unique AFP-mimetic structure, the polyacrylic acid-DMSO hydrogel prepared by rapid one-pot photo-polymerization embodies merits of excellent flexibility, large ionic conductivity, and strong interfacial adhesiveness with almost all types of surfaces at temperature down to −40 °C. As-assembled supercapacitor delivers remarkable specific capacitance of 73 F g −1 at −40 °C (∼70% of the capacitance at 20 °C), 84.5% of capacitance retention after 5000 charge-discharge cycles at −40 °C, and 85.8% of capacitance retention after 1000 cycles at an extreme bending angle of 180° and −40 °C, evidently manifesting high efficiency/stability toward cyclic charge-discharge operation and structure deformation in cold climates. It is believed that this work will play an exemplary role in designing anti-freezing hydrogel electrolytes for reliable, flexible electronic devices working at extremely cold environments.
研究领域:
材料科学
·
电化学
·
柔性电子
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2019
·
IF 5.383
Zhonghua Yu,Lingting Huang,Jialun Chen,Ying Tang,Biyun Xia,Dianping Tang
This work designed a new photoelectrochemical (PEC) immunoassay for the ultrasensitive detection of alpha-fetoprotein (AFP) based on the flower-like β-In 2 S 3 @carbon dots (CDs). The photocurrent of the as-prepared heterogeneous nanostructure was enhanced significantly under ultraviolet (UV), visible (Vis) and near-infrared (NIR) irradiation thanks to the more generation of carriers and less electron-hole pairs recombination with CDs. The three-layer sandwich-like immunocomplex would be formed upon the target AFP existed, the ascorbic acid 2-phosphate (AA2P) was subsequently transformed into ascorbic acid (AA) owing to the catalysis of alkaline phosphatase-conjugated rabbit polyclonal anti-human AFP (ALP-Ab2). Without additional applied voltage, the photocurrent of the β-In 2 S 3 @CDs-modified electrode was positively correlated with the increasing AA level in the detection cell. Under optimal conditions, the developed PEC immunosensing platform exhibited good reproducibility and high sensitivity for the determination of target AFP within a dynamic working range from 0.5 to 50 ng mL −1 at a detection limit of 37.9 pg mL −1 . In addition, the method accuracy relative to human AFP ELISA kit was evaluated by analyzing human serum specimens, and a good match between two methods was obtained. Such the increasing photocurrent through full-spectrum responsive mode gives a new horizon to develop highly sensitive PEC immunoassay in early clinical diagnosis by monitoring disease-related biomarkers.
研究领域:
分析化学
·
生物医学工程
·
临床诊断
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2019
·
IF 3.206
Zhi Zhang,Yueping Guan,Guoli Xu,Chen Guo
In this submission, a novel washing-free immunosensor was designed for chemiluminescence immunoassay (CLIA) of tumor marker using human Alpha-fetoprotein (AFP) as a representative. Reactive groups were introduced on the surface of the solvothermally prepared Fe 3 O 4 magnetic submicron particles (MSPs) and the dual-functional polyethylene glycol (PEG) linkers were modified to reduce the non-specific adsorption capacity of the particle surface and further to immobilize N -(4-aminohexyl)- N -ethylisoluminol (AHEI) and anti-AFP antibody on the surface of the particles. After incubation with AFP and horseradish peroxidase (HRP) labeled anti-AFP antibody respectively, the formed sandwich-type immunocomplexes on the particle surface could lead to the close proximity between AHEI and HRP, thus eventually leads to an increase in the detected chemiluminescence (CL) signal. As a bound HRP labeled anti-AFP antibody produces much stronger CL signal than an unbound one, this approach eliminates the time- and labor-consuming washing steps usually required of such assays. Under the optimal conditions, this present method shows a wide quantitative range from 1 to 250 ng mL −1 with a detection limit of 1.751 ng mL −1 . The detection limit was sufficient for measuring physiological (0–20 ng mL −1 ) and clinical (>20 ng mL −1 ) AFP levels. This method can also be applied in serum samples, and also avoid the problem of particle aggregation caused by multiple separation and washing steps.
研究领域:
生物医学工程
·
癌症诊断
·
分子生物学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Science
·
2023
·Vol. 10
·期 24
·2301658
·
IF 15.1
Rui Li,Hongli Fan,Hanlin Zhou,Youqian Chen,Qingcai Yu,Wenjun Hu,Gang L. Liu,Liping Huang
Developing plasmonic biosensors that are low-cost, portable, and relatively simple to operate remains challenging. Herein, a novel metasurface plasmon-etch immunosensor is described, namely a nanozyme-linked immunosorbent surface plasmon resonance biosensor, for the ultrasensitive and specific detection of cancer biomarkers. Gold-silver composite nano cup array metasurface plasmon resonance chip and artificial nanozyme-labeled antibody are used in two-way sandwich analyte detection. Changes in the biosensor's absorption spectrum are measured before and after chip surface etching, which can be applied to immunoassays without requiring separation or amplification. The device achieved a limit of alpha-fetoprotein (AFP) detection < 21.74 fM, three orders of magnitude lower than that of commercial enzyme-linked immunosorbent assay kits. Additionally, carcinoembryonic antigen (CEA) and carbohydrate antigen 125 (CA125) are used for quantitative detection to verify the universality of the platform. More importantly, the accuracy of the platform is verified using 60 clinical samples; compared with the hospital results, the three biomarkers achieve high sensitivity (CEA: 95.7%; CA125: 90.9%; AFP: 86.7%) and specificity (CEA: 97.3%; CA125: 93.9%; AFP: 97.8%). Due to its rapidity, ease of use, and high throughput, the platform has the potential for high-throughput rapid detection to facilitate cancer screening or early diagnostic testing in biosensing.
研究领域:
生物传感
·
医学诊断
·
纳米技术
·
光学
·
癌症研究
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2016
·
IF 7.145
Jinjin Guo,Junchun Wang,Junqing Zhao,Zilin Guo,Yuzhong Zhang
In this work, a novel electrochemical immunoassay protocol has been reported for simultaneous determination of multiple tumor biomarkers based on DNA hybridization chain reaction (HCR) for signal amplification. Alpha-fetoprotein (AFP) and prostate specific antigen (PSA) were selected as model biomarkers. The immunoassay protocol contained primary antibodies immobilized on gold nanoparticles (Au NPs), secondary antibodies conjugated with DNA concatemer from HCR of primer, auxiliary probe, and signal probe labeled with signal molecules (methyleneblue (MB) and ferrocene (Fc)). In the presence of target biomarkers, the sandwich immunocomplex was formed between the primary antibodies and secondary antibodies bioconjugates carrying numerous signal molecules. As a result, two well-resolved reduction peaks, one was at −0.35 V (corresponding to MB) and other was at 0.33 V (corresponding to Fc; both vs SCE), were obtained in differential pulse voltammetry, and peak currents changed were related to the level of biomarkers. Under optimal conditions, the electrochemical immunoassay exhibited a wide linear response range (0.5 pg mL–1 to 50 ng mL–1) and low detection limits (PSA, 0.17 pg mL–1; AFP, 0.25 pg mL–1) (at S/N = 3). In addition, the immunoassay was evaluated by analyzing simulate human serum sample, and the recoveries obtained were within 99.4–107.6% for PSA and 97.9–108.2% for AFP, indicating the immnuoassay could be applied to the simultaneous detection of AFP and PSA in human serum samples.
研究领域:
生物化学
·
分析化学
·
纳米技术
·
癌症研究
·
生物医学工程
✓ 已验证
DOI
PubMed
高影响因子
NANO
·
2018
·
IF 1.1
Yongfeng Gao,Yuanhui Feng,Lu Zhou,Lucia Petti,Zhe Wang,Jun Zhou,Shusen Xie,Jian Chen,Yanping Qing
Ultrasensitive detection of alpha-fetoprotein (AFP) is critical for the early diagnosis of liver cancer. In this work, a novel surface-enhanced Raman scattering (SERS)-based immunoassay complex has been successfully developed for the detection of AFP by using the Au-Ag alloy nanoparticals and the Ag/AgBr hybrid nanostructure. As the typical bimetal or metal/semiconductor plasmonic materials, besides the strong SERS enhancement characteristics, the Au-Ag alloy nanoparticals exhibit excellent monodispersity and the Ag/AgBr hybrid nanostructure demonstrates good stability. The experimental results show that the SERS-based immunoassay of AFP presents a low limit of detection of 1.86 fg/mL and a broad dynamic range from 2 fg/mL to 0.8 μ g/mL. Furthermore, the clinical applicability of the proposed SERS-based immunoassay has been assessed by the detection of AFP in the human serum samples of cancer patient and healthy person. The test data are consistent well with that of chemiluminescence immunoassay (CLIA) in the relative errors of − 8.82–8.06% and show better detection sensitivity. It reveals that the proposed immunoassay protocol is significant for giving insight into the design of ultrasensitive biosensor and the point-of-care testing of cancers.
研究领域:
分析化学
·
生物医学工程
·
纳米技术
·
癌症研究
·
临床诊断
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2021
·
IF 7.46
Jianguo Chang,Nailong Gao,Peng Dai,Ziming Zhu,Hui You,Wei Han,Lu Li
The powerful immunoassay has attracted increasing attention for detecting trace substances. Herein, based on the co-coupling of phenylboronic acid and Protein A for oriented antibodies immobilization, we proposed a polymeric device-based fluorescence immunoassay with enhanced assay performance for Alpha-fetoprotein (AFP) analysis. Unlike traditional physical absorption or chemical covalent conjugation to immobilize antibodies, in this immunoassay, the bioreactivity of AFP antibody was maximumly obtained owing to the oriented immobilization manner. The package density of AFP antibody on the polymethylmethacrylate (PMMA) surface is significantly improved because of the co-coupling case associated distance effect. In addition, the non-specific absorption is greatly inhibited with the combined using of zwitterionic 2-methacryloyloxyethyl phosphorylcholine (MPC) and bovine serum albumin (BSA). These integrated features facilitate the output of strong fluorescence in the presence of AFP but emit very weak background in the absence of AFP. After a typical sandwich immunoreaction, the recorded fluorescence intensity of the immunosensor is proportional to the AFP concentration, showing excellent sensitivity, specificity, and reliability for AFP determination. Comparative studies show the co-coupling is superior than its single coupling counterparts. We envision this unique immunoassay can provide a new avenue for building immunosensors in the fields of disease diagnosis, food safety detection, and environmental monitoring.
研究领域:
生物医学工程
·
分析化学
·
医学诊断
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2019
·
IF 6.393
Xiaoqing Zhao,Jing Wang,Hou Chen,Hui Xu,Liangjiu Bai,Wenxiang Wang,Huawei Yang,Donglei Wei,Baiqing Yuan
A novel electrochemical immunoassay platform for multi-signal amplification has been constructed and applied to the simultaneous detection of three tumor markers (TMs). The platform was successfully developed by polyethyleneimine (PEI)-polydopamine (PDA)/reduced graphene oxide (rGO) nanocomposites. PDA/rGO as the substrates can simultaneously load with detection antibodies (Ab 2 ) and large amounts of PEI, which PEI were further used to immobilize different signal labels. Three TMs of carcinoembryonic antigen (CEA), prostate specific antigen (PSA) and alpha fetoprotein (AFP) were employed as potential factors. Ferrocenecarboxylic acid (Fc), anthraquinone-2-carboxylic acid (Aq) and acetylsalicylic acid (ASA) were employed as distinguishable signal labels. Electrochemical responses of designed sandwich-type immunosensor were successfully investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The multiplexed immunoassay displayed excellent linear response in the range of 0.102 pg/mL–112 ng/mL for CEA and PSA, 0.117 pg/mL–117 ng/mL for AFP. The detection limit of three TMs were 91 fg/mL, 101 fg/mL and 83 fg/mL for CEA, PSA and AFP, respectively. Moreover, this electrochemical immunoassay platform exhibited excellent reproducibility, sensitivity and selectivity for the simultaneous detection of multiple biomarkers.
研究领域:
生物医学工程
·
分析化学
·
纳米技术
·
电化学
·
生物传感器
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）