ANALYTICAL CHEMISTRY
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2022
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IF 8.008
Guojuan Zhang,Yujie Han,Zhiguang Liu,Lifang Fan,Yujing Guo
A triple-amplified and ratiometric electrochemical aptasensor for CA125 was designed based on hemin–graphene/SH-β-cyclodextrin@PdPt nanoflower (H-Gr/SH-β-CD@PdPtNF) composites and an exonuclease I (Exo I)-assisted strategy. In the nanocomposite, hemin acts as an internal reference signal owing to the reversible heminox/heminred pair. PdPtNFs can significantly improve the electron transfer rate. SH-β-CD can efficiently enrich quercetin probes through host–guest recognition and increase the second indicator signal. In the presence of CA125, due to the specific binding between the aptamer and CA125, the conformational change of dsDNA (designed by the CA125 aptamer and its complementary DNA) results in the release of quercetin embedded in dsDNA. Subsequently, the free quercetin and DNA fragments are enriched on the H-Gr/SH-β-CD@PdPtNF-modified electrode. Thus, an enhanced oxidation peak from quercetin (IQ) and a reduced peak from hemin (Ihemin) can indicate the same biological identification event. In addition, the recycling amplification of CA125 by Exo I can effectively assist the increase of the quercetin signal. The value of IQ/Ihemin is linear with the concentration of CA125 in the range from 6.0 × 10–4 to 1.0 × 103 ng/mL, and the limit of detection is 1.4 × 10–4 ng/mL. The recovery of CA125 in human blood serum samples was from 99.2 to 104.4%. The proposed sensor is sensitive and reliable, which provides an avenue for the development of triple amplification and ratiometric signal strategies for detecting tumor markers in clinical diagnostics.
研究领域:
生物医学工程
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临床诊断
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分析化学
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DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
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2019
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IF 5.256
Jiaxin Zheng,Xiaolun Peng,Yijia Wang,Ting Bao,Wei Wen,Xiuhua Zhang,Shengfu Wang
The development of some sensitive methods for MUC1 is critical for preclinical diagnosis of tumors. In this experiment, we built a triple-amplified electrochemical aptasensor to achieve sensitive detection of MUC1, which was based on exonuclease III (Exo III)-assisted with strand displacement reaction and enzyme catalytic strategy. Firstly, with the help of Exo III, MUC1 and aptamer could be recycled during the cycle I, the single stranded DNA-1 (S-1) was produced during the process and was introduced to the hybride reaction on the electrode. Secondly, during the cycle II, strand displacement reaction was triggered on the electrode with the adding of hairpin DNA-2 (H-2). Thirdly, after the gold nanoparticles (AuNPs)-DNA-enzyme conjugates hybrided with the H-2 on the electrode, the AuNPs-DNA-enzyme conjugates could act as signal probe to produce electrochemical catalytic signal. We used the fabricated triple-amplified electrochemical aptasensor that could detect MUC1 from 0.1 pg mL −1 to 10 ng mL −1 with the detection limit of 0.04 pg mL −1 under the optimized experimental conditions. The constructed triple-amplified electrochemical aptasensor could be applied in real samples determination. Besides, the strategy can be applied to detect other proteins for health monitoring.
研究领域:
生物化学
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分析化学
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生物医学工程
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癌症诊断
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DOI
PubMed
高影响因子
ANALYST
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2020
·Vol. 145
·期 10
·3605-3611
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IF 3.978
Li-Ping Jia,Zhe Feng,Ruo-Nan Zhao,Rong-Na Ma,Wei Zhang,Lei Shang,Wen-Li Jia,Huai-Sheng Wang
A sensitive and enzyme-free electrochemical aptasensor was constructed for the sensing of 8-hydroxy-2′-deoxyguanosine (8-OH-dG). In the process of constructing the aptasensor, triple signal amplification strategies were introduced to enhance the sensitivity. First, every aptamer/pDNA complex immobilized on magnetic beads could release three kinds of pDNAs when 8-OH-dG was introduced, which caused three-fold magnification of the target. Second, the released three kinds of pDNAs initiated catalyzed hairpin assembly between two hairpin DNAs (HP1 and HP2) on a gold electrode. Meanwhile, the three kinds of pDNAs were released again by a strand displacement reaction to obtain the next catalyzed hairpin assembly. Third, the emerging toehold of HP2 further induced a hybridization chain reaction (HCR) between two hairpin DNAs (HP3 and HP4), forming a long double-stranded DNA concatemer on the surface of the electrode. Finally, [Ru(NH3)6]3+, an electroactive cation, was adsorbed onto the long dsDNA concatemer by electrostatic interactions and consequently, an electrochemical signal was generated. Under this triple signal amplification, a low detection limit down to 24.34 fM has been obtained for 8-OH-dG determination, which is superior to those of most previously reported methods.
研究领域:
分析化学
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生物化学
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纳米技术
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电化学
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DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
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2013
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IF 5.437
Kun Shang,Xindong Wang,Bing Sun,Ziqiang Cheng,Shiyun Ai
A novel sandwich-type electrochemical immunosensor was fabricated for ultrasensitive detection of subgroup J of avian leukosis virus (ALVs-J) by employing β -cyclodextrin-ferrocene (CD-Fc) host–guest complex multifunctional Fe 3 O 4 nanospheres as labels and β -cyclodextrin functional graphene sheets (CD-GS) nanocomposite as sensor platform. The sensitivity was greatly improved based on the triple amplification strategy. Firstly, the CD-GS improved the electron transfer rate as well as increasing the surface area to capture a large amount of primary antibodies (Ab 1 ). Secondly, the CD on the Fe 3 O 4 surface with strong recognition capability could form stable CD-Fc host–guest inclusion complex and provided larger free room for the conjugation of secondary antibodies (Ab 2 ) and glucose oxidase (GOD). Finally, the conjugated GOD exhibited extraordinary electrochemical biocatalysis towards the reduction reaction of Fc + by glucose. Under the optimized conditions, the electrochemical immunosensor exhibited a wide working range from 10 2.27 –10 3.50 TCID 50 /mL (TCID 50 : 50% tissue culture infective dose) with a low detection limit of 10 2.19 TCID 50 /mL ( S / N =3). The selectivity, reproducibility, and stability are acceptable. The assay was evaluated for real avian serum sample, receiving satisfactory results. This new type of triple amplification strategy may provide potential applications for the clinic application.
研究领域:
生物化学
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医学检测
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纳米材料科学
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DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
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2018
·
IF 8.173
Xiaolun Peng,Jinlin Zhu,Wei Wen,Ting Bao,Xiuhua Zhang,Hanping He,Shengfu Wang
In the paper, a triple-amplified biosensor was built for the purpose of ultrasensitive methyltransferase (Dam MTase) activity detection and inhibitor screening based on in-situ synthesized silver nanoclusters (AgNCs) as signal probes to provide amplified current signal coupling with gold nanoparticles/electrochemical reduced graphene oxide (AuNPs/ERGO) hybrids and hybridization chain reactions (HCR) amplification strategy. For biosensor preparation, the AuNPs/ERGO hybrids were firstly generated on the electrode surface by electrochemical co-reduction method, then the ds-DNA structures which comprised the specific recognition sequences (5′-G-A-T-C-3′) of the Dam MTase and the restrictive endonuclease DpnI were formed on the electrode by the hybridization of the assistant DNA with the capture DNA. The presence of Dam MTase methylated partial ds-DNA structures on the electrode which could be digested by DpnI and could not undergo HCR process. The unmethylated ds-DNA structures underwent HCR process to further hybridize with DNA1 and DNA2 to form ds-DNA superstructures as effective template for AgNCs in-situ synthesis. Oxidation peak current of silver was obtained as signal output for Dam MTase detection. Integrated synthesis and detection in one as well as combined metal nanocluster with DNA superstructures, this biosensor showed a good performance for Dam MTase activity detection with a detection limit of 0.0073 U/mL. Compared with reported biosensor, the designed biosensor showed high sensitivity and had potential in clinical diagnosis as well as inhibitor screening.
研究领域:
生物化学
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分析化学
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生物传感器
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分子生物学
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DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2014
·
IF 5.825
Kang Shao,Jing Wang,Xiaochun Jiang,Feng Shao,Tingting Li,Shiyi Ye,Lu Chen,Heyou Han
Triply amplified electrochemical biosensors have attracted particular attention in the detection of low-abundance biomarkers. The universal construction routes for nonenzymatic triply amplified and even multiply amplified biosensors are extremely desirable but remain challenging. Here, we proposed a “stretch–stowage–growth” strategy to tunably fabricate a nonenzymatic triply amplified or multiply amplified electrochemiluminescence (ECL) immunosensor for ultrasensitive determining pseudorabies virus (PrV) antibody. Based on the matrix role of gold nanoparticle-graphene nanosheet (Au–GN) hybrids, carrier role of silicon nanoparticles (SNPs) and bridge role of “biotin–streptavidin–biotin” (B–SA–B) structure, the establishment processes were defined as “stretch”, “stowage”, and “growth”, respectively. Relying on the interaction of antigen–antibody and of B-SA, the “Au–GN/PrV (Ag)/PrV antibody (Ab1)/biotinylated IgG (B-Ab2)/SA/biotinylated Ru(bpy)32+-encapsulated SNPs (B–Ru@SNPs)” triply amplified biosensor could be fabricated and exhibited better analytical performance not only toward monoclonal PrV antibody with a linear detection range from 50 ng mL–1 to 1 pg mL–1 and a detection limit of 0.40 pg mL–1, but also toward actual serum samples when compared with enzyme-linked immunosorbent assay and fluorometry. Furthermore, multiply amplified biosensors could be conveniently fabricated by controllably repeating the combination of B–Ru@SNPs and SA to form the B–SA–B structure. After it was repeated three times, the multiply amplified biosensor stretched to the maximum of signal amplification and achieved a luminescence quantum efficiency about 23.1-fold higher than the triply amplified biosensor. The tunable biosensor exhibits good stability, acceptable reproducibility and accuracy, suggesting its potential applications in clinical diagnostics.
研究领域:
分析化学
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纳米技术
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生物医学工程
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病毒学
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免疫学
✓ 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）