Analytical Methods
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2015
·Vol. 7
·期 6
·2391-2398
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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
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分析化学
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医学诊断
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传感器技术
✓ 已验证
DOI
高影响因子
SENSORS
·
2018
·Vol. 18
·期 6
·1765
·
IF 2.475
Zhen Yang,Huanhuan Wang,Pengfei Guo,Yuanyuan Ding,Chong Lei,Yongsong Luo
Cardiac biomarkers (CBs) are substances that appear in the blood when the heart is damaged or stressed. Measurements of the level of CBs can be used in course of diagnostics or monitoring the state of the health of group risk persons. A multi-region bio-analytical system (MRBAS) based on magnetoimpedance (MI) changes was proposed for ultrasensitive simultaneous detection of CBs myoglobin (Mb) and C-reactive protein (CRP). The microfluidic device was designed and developed using standard microfabrication techniques for their usage in different regions, which were pre-modified with specific antibody for specified detection. Mb and CRP antigens labels attached to commercial Dynabeads with selected concentrations were trapped in different detection regions. The MI response of the triple sensitive element was carefully evaluated in initial state and in the presence of biomarkers. The results showed that the MI-based bio-sensing system had high selectivity and sensitivity for detection of CBs. Compared with the control region, ultrasensitive detections of CRP and Mb were accomplished with the detection limits of 1.0 pg/mL and 0.1 pg/mL, respectively. The linear detection range contained low concentration detection area and high concentration detection area, which were 1 pg/mL–10 ng/mL, 10–100 ng/mL for CRP, and 0.1 pg/mL–1 ng/mL, 1 n/mL–80 ng/mL for Mb. The measurement technique presented here provides a new methodology for multi-target biomolecules rapid testing.Keywords:myoglobin;C-reactive protein;Dynabeads;magnetoimpedance;microfluidic device
研究领域:
生物医学工程
·
诊断学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2014
·
IF 6.451
Tao Wang,Zhen Yang,Chong Lei,Jian Lei,Yong Zhou
A Dynabeads-labeled magnetic immunoassay (MIA) has been developed by using an integrated giant magnetoimpedance (GMI) biosensor for the detection of alpha-fetoprotein (AFP). The GMI biosensor (Cr/Cu/NiFe/Cu/NiFe/Al 2 O 3 /Cr/Au films) integrated magnetic sensing elements and a biomolecular immunoplatform. Au film was modified with 11-Mercaptoundecanoic acid (11-MUA) for the immobilization of AFP monoclonal antibody . Double antibody sandwich immunoassay was used to specifically capture and label AFP antigen. Functionalized Dynabeads were conjugated to AFP antigen by streptavidin–biotin binding assay. GMI responses were measured for sensitive detection of AFP from 1 to 10 ng/ml. Our results revealed that the presence of AFP on the biosensor improved the GMI effect owing to the induced magnetic dipole of superparamagnetic Dynabeads, and the GMI ratio was greatly increased at high frequency. Specificity of MIA was tested through the use of 1% bovine serum albumin (BSA). The underlying biophysical mechanisms responsible for the enhanced GMI effect in the detection of AFP were discussed. This work provides a complex lab-on-chip MIA for the detection of biomarker, which may open up a new way for the development of GMI-based MIA in clinical trials .
研究领域:
生物医学工程
·
分子诊断学
✓ 已验证
DOI
PubMed
高影响因子
BIOMEDICAL MICRODEVICES
·
2013
·Vol. 16
·期 2
·237-243
·
IF 2.718
Lei Jian,Lei Chong,Wang Tao,Yang Zhen,Zhou Yong
An investigation of targeted biomolecules was accomplished by combining a micro-fluxgate-based bio-sensing system and Dynabeads. The fluxgate sensor for biomolecule detection was fabricated by Micro Electro-Mechanical system technology, including thick photoresist lithography, electroplating and chemical wet etching. The magnetic core of the sensor was made of Fe-based amorphous ribbon core and three dimension solenoid coils were used as magnetic sensitive elements. The micro-fluxgate-based bio-sensing system was characterized firstly in different concentrations of Dynabeads, and a concentration as low as 100 ng/ml was detected with an external dc magnetic field in the range of 525 μT to 875 μT. Sandwich assays are performed using antibody-antigen pair combination of biotin-streptavidin on a separated Au film substrate surface with a self-assembled layer. Detection of Alpha Fetoprotein antigens with different concentrations was performed and a minimum detectable concentration of 1 pg/ml was achieved by the bio-sensing system. It is of considerable interest due to its potential application in the biomedical field based on known specific binding of target and labels.
研究领域:
生物医学工程
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分子生物学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED PHYSICS LETTERS
·
2013
·Vol. 103
·期 20
·
IF 3.794
Lei Jian,Lei Chong,Wang Tao,Yang Zhen,Zhou Yong
In this work, a micro-fluxgate-based biosensor was designed for the detection of carcinoembryonic antigen (CEA) labeled by Dynabeads. The sensor with Fe-based amorphous core and three dimension solenoid coils was fabricated by Micro Electro-Mechanical system technology. Sandwich assays are performed using antibody-antigen pair combination of biotin-streptavidin assay on a separated Au film substrate surface with a self-assembled layer. With dc magnetic fields in the range of 560 μ T to 875 μ T, detection of CEAs with different concentrations was performed and a minimum detectable concentration of 1 pg/ml was achieved. Furthermore, CEA samples with different concentrations can be distinguished.
研究领域:
生物医学工程
·
诊断学
✓ 已验证
产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2016
·Vol. 183
·期 8
·2385-2393
·
IF 4.831
Sun Xue-cheng,Lei Chong,Guo Lei,Zhou Yong
We describe a micro fluxgate based device with rectangular magnetic core for the determination of prostate specific antigen (PSA) labeled with Dynabeads. A sandwich immunoassay was employed where PSA is captured on a gold film modified with a self-assembled monolayer of antibody. The secondary antibody is labeled with Dynabeads. By applying a DC magnetic fields in the range of 460 to 700 μT, PSA can be detected with detection limit as low as 0.1 ng mL −1 . This micro fluxgate-based assay offers the advantages of miniaturization, simple and conveniently manipulation, re-usability and stability. In our perception, it offers a viable approach towards clinical determination of PSA or other biomarkers.
A separable detection method based on micro fluxgate and immunomagnetic beads was developed for detection of prostate specific antigen (PSA). Sandwich immunoassay was employed where PSA is captured on a gold film modified with a self-assembled monolayer of antibody. By applying a DC magnetic fields in the range of 460 to 700 μT, PSA can be detected with detection limit as low as 0.1 ng mL −1 , and this bio-sensing system can also give an approximate quantitation to the concentrations of them.
研究领域:
生物传感器
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医学诊断
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分子生物学
✓ 已验证
产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2016
·Vol. 183
·期 3
·1107-1114
·
IF 4.831
Sun Xue-cheng,Lei Chong,Guo Lei,Zhou Yong
We report on a giant magnetoresistance (GMR) based immunosensor for the carcinoembryonic antigen (CEA) labeled with superparamagnetic microparticles (Dynabeads). The GMR sensor contains 200 GMR strips and was fabricated by micro-electromechanical system (MEMS) technology. This system can detect Dynabeads in concentrations down to 10 ng⋅mL −1 . Sandwich immunoassays were employed on the surface of a gold film modified with a self-assembled monolayer and using biotinylated secondary antibody against CEA and streptavidinylated Dynabeads. With DC magnetic fields in the range of 40 to 90 Oe, CEA can be detected with a detection limit as low as 10 pg⋅mL −1 . Samples spiked with different concentrations of CEA can be distinguished clearly, and the method is deemed to be well suited for clinical use.
Make use of antigen-antibody immune reaction, Dynabeads that conjugated with polyclonal CEA antibodies were captured onto the surface of Au film which immobilize of monoclonal CEA antibodies. Under the dc magnetic field magnetizing, the superparamagnetism Dynabeads induced a weak magnetic field that can be detected by the nearby GMR sensor, which reveals the presence of CEA. GMR: giant magneto-resistance CEA: carcinoembryonic antigens.
研究领域:
生物传感器
·
生物医学工程
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分子诊断
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癌症研究
✓ 已验证
产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2016
·Vol. 183
·期 6
·1831-1837
·
IF 4.831
Yang Zhen,Liu Yan,Lei Chong,Sun Xue-cheng,Zhou Yong
We report on a method for ultrasensitive detection and quantification of the pathogen Escherichia coli ( E. coli ), type O157:H7. It is using a tortuous-shaped giant magnetoimpedance (GMI) sensor in combination with an open-surface microfluidic system coated with a gold film for performing the sandwich immunobinding on its surface. Streptavidin-coated super magnetic Dynabeads were loaded with biotinylated polyclonal antibody to capture E. coli O157:H7. The E. coli -loaded Dynabeads are then injected into the microfluidics system where it comes into contact with the surface of gold nanofilm carrying the monoclonal antibody to form the immunocomplex. As a result, the GMI ratio is strongly reduced at high frequencies if E. coli O157:H7 is present. The sensor has a linear response in the 50 to 500 cfu·mL −1 concentration range, and the detection limit is 50 cfu·mL −1 at a working frequency of 2.2 MHz. In our perception, this method provides a valuable tool for developing GMI-based microfluidic sensors systems for ultrasensitive and quantitative analysis of pathogenic bacteria. The method may also be extended to other sensing applications by employing respective immunoreagents.
Fig. (a) Graphical illustration of the test setup. (b) Relationship of GMI signal vs. E. coli O157:H7 concentration.
研究领域:
生物医学工程
·
微流控技术
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传感技术
·
病原体检测
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磁感测技术
✓ 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）