JOURNAL OF FLUORESCENCE
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2024
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IF 2.6
Li Ling,Li Zheng-Ling,Wang Wei,Long Xin-Xin,Liu Ping,Wang Guo-Tian,Sun Shi-Qing,Du Rong-Lian
The rapid and accurate detection of programmed death-ligand 1 (PD-L1) expression is of great value in the diagnosis and treatment of tumors. ELISA-based traditional method is the gold standard for protein detection, but there are still some shortcomings, especially the antigen-antibody dependence, greatly increased the detection time and cost. This work constructed a label-free fluorescent probe for rapid and sensitive detection of PD-L1 using a truncated aptamer as recognition molecules and double-stranded DNA specific dyes (SYBR Green I) as signal units. After a series of optimization conditions, this probe has good detection capability for PD-L1 in buffer solution with the detection limit as low as 0.68 ng/mL. Due to the specific recognition ability of aptamer and target, this method also has good selectivity for PD-L1 detection. The recovery of PD-L1 in human serum samples ranges from 86.20 to 96.36%. Compared with other methods, this strategy does not need to be marked, and does not need other complex design and purification process, but simple operation process and strong anti-interference ability. The whole detection process can be completed within 20 min and has good application prospect. This work will provide reference for drug dosage and prognosis evaluation of specific tumor therapy.
研究领域:
癌症生物学
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分子诊断
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生物技术
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DOI
PubMed
高影响因子
ANALYST
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2013
·Vol. 138
·期 17
·4737-4740
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IF 3.969
Chenchen Ge,Junhua Chen,Wei Wu,Zhiyuan Fang,Lingbo Chen,Qi Liu,Lin Wang,Xuerong Xing,Lingwen Zeng
An enzyme-free and label-free fluorescence turn on biosensor for amplified copper(II) ion (Cu2+) detection has been constructed based on self-assembled DNA concatamers and Sybr Green I. This assay is simple, inexpensive and sensitive, enabling quantitative detection of as low as 12.8 pM Cu2+.
研究领域:
分析化学
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生物传感器
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纳米技术
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
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2019
·
IF 5.399
Xiang-Xiu Chen,Zheng-Zhong Lin,Cheng-Yi Hong,Qiu-Hong Yao,Zhi-Yong Huang
A dichromatic label-free aptasensor was described for sulfadimethoxine (SDM) detection. Compared with the binding of SDM-aptamer to SDM, the higher affinity of aptamer to cDNA may result in the hybridization of dsDNA. In the presence of SDM, the aptamer specifically binds to SDM, leading to a blue color of AuNPs in deposit and fluorescence at 530 nm in supernatant after adding cDNA and SGI. With no target of SDM, AuNPs protected with the aptamer re-disperse in PBS with a red color, and no fluorescence occurs in supernatant. Based on the principle, SDM can be quantitatively detected through both fluorescent emission and AuNPs color changes with recoveries ranging from 99.2% to 102.0% for fish and from 99.5% to 100.5% for water samples. An analytical linear range of 2–300 ng mL −1 was achieved with the detection limits of 3.41 ng mL −1 for water and 4.41 ng g −1 for fish samples (3 σ , n = 9).
研究领域:
分析化学
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环境科学
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食品安全
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
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2022
·
IF 9.231
Pengfei Ma,Hua Ye,Hualin Guo,Xiaoyuan Ma,Lin Yue,Zhouping Wang
Herein, for the first time, a novel truncation strategy for aptamers’ sequences based on molecular docking was reported for the first time. T-2 toxin and AFB 1 aptamers were employed as models and fluorescence polarization was used to measure the affinity of aptamers. The T-2 toxin aptamer (T40) with 40 bases and the AFB 1 aptamer with 32 bases were successfully obtained with increased affinities compared with original aptamers. Meanwhile, circular dichroism, FAM-BHQ1 dual labeled T40, enzyme digestion, and molecular dynamics simulation were performed to investigate the binding mechanism between aptamer T40 and T-2 toxin. Finally, based on MnO 2 nanosheet and the fluorescence amplification effect of SYBR Green I, simplified and rapid fluorescence detection of T-2 toxin was achieved with a detection range of 0.03 nM to 30 nM, indicating the great potential of aptamer in practical detection applications.
研究领域:
分析化学
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分子生物学
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毒理学
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纳米技术
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DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
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2018
·
IF 2.746
Bin Zhou,Xin-Yi Yang,Yong-Sheng Wang,Jie-Can Yi,Zhen Zeng,Huan Zhang,Ya-Ting Chen,Xi-Jiang Hu,Qing-Li Suo
A label-free fluorescence aptasensor based on conformational switching of aptamer induced by Cd 2+ was established for the good selective determination of Cd 2+ . The aptamer could act as a recognition element for Cd 2+ . SYBR green I (SG), as a signal reporter, can bind to the small groove of double-stranded DNA (dsDNA) constituted the aptamer and the complementary strand, establishing the dsDNA-SG complex and generating high fluorescence intensity . In the presence of Cd 2+ , the specific recognition and binging of aptamers preferentially with Cd 2+ induce free of complementary strands from dsDNA and conformational switching of aptamer from dsDNA to a stem-loop structure, fluorescence intensity of system decrease dramatically. Under the optimum experiment parameters, the aptasensor shows a good linear range from 1.12 μg L −1 to 224.82 μg L −1 and the excellent detection limit as low as 0.34 μg L −1 . The relative standard deviations (RSD) for determination of Cd 2+ (n = 8) were lower than 4%, and the recoveries were in the range of 98.57% ~ 102.49%. The use of fluorescence aptasensor has good selectivity and does not require any sample treatment or target preconcentration for the detection of Cd 2+ in real samples.
研究领域:
分析化学
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环境科学
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生物化学
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DOI
高影响因子
MICROCHEMICAL JOURNAL
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2024
·
IF 4.9
Yizhi Zhou,Qiang Liu
The sensitive and label-free detection of microRNA (miRNA) is crucial for the comprehension of miRNA-related pathological process, such as glioma. Here, we utilized a SYBR Green I (SG) catalytic photosensitization colorimetric reaction in conjunction with target recognition-induced exonuclease-iii (Exo-iii) assisted cascade toehold assembly amplification to achieve highly sensitive and label-free miRNA detection. In this research, the photosensitized generation of 1 O 2 by SG could directly oxidize 3,3′,5,5′-tetramethylbenzidine (TMB) without the need for H 2 O 2 oxidation or enzyme catalysis, which simplifies the experimental procedures and renders the method highly stable. Furthermore, the Exo-iii enhances the target recognition induced catalytic chain assembly, thereby forming cascade signal amplification and providing the method with a significantly higher level of sensitivity than conventional colorimetric miRNA detection methods. Based on this, the proposed method exhibits a low limit of detection of 2.1 fM for miRNA-212 detection. Taking the merit of the high sensitivity, portability, and simplicity, the proposed method can serve as a highly effective nucleic acid detection tool and can facilitate the advancement of biosensors for point-of-care testing (POCT) and clinical disease diagnosis.
研究领域:
生物化学
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分子诊断
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医学检测
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DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
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2016
·
IF 7.476
Chunjing Feng,Zhun Hou,Wei Jiang,Lihong Sang,Lei Wang
Herein, a sensitive and enzyme-free assay for adenosine detection has been developed on the basis of binding induced colocalization activated hybridization chain reaction (HCR) strategy on the surface of magnetic nanobead . First, the recognition probe was fabricated and divided into two parts: the Apt-1 that composed a part of adenosine aptamer and toehold domain, and the Apt-2 that consisted of another part of adenosine aptamer and branch migration domain. The Apt-1 was immobilized on a streptavidin-magnetic nanobead (streptavidin-MNBs) that played the roles of enrichment and separation. Then the recognition event of adenosine could bring the two parts of aptamer together and induce the colocalization of toehold domain and branch migration domain, which could serve as an integrated initiator to trigger the HCR, producing a long nicked double-stranded polymer. Finally, the intercalating dye SYBR Green I was inserted into the polymer, generating an enhanced fluorescence signal. In this strategy, the initiator was divided into two parts and could be suppressed effectively in the absence of adenosine. Utilizing the separated function, the spontaneous hybridization of H1 and H2 could be avoided, and a low background could be acquired. Moreover, through the double amplification of HCR and multimolecules binding of SYBR Green I, highly sensitive and enzyme-free detection were achieved. The detection limit for adenosine detection was 2.0×10 −7 mol/L, which was comparable or superior to the previous aptasensors . Importantly, adenosine analysis in human urines has been performed, and this strategy could significantly distinguish the adenosine content in normal human urines and cancer patient urines, suggesting that this proposed assay will become a reliable and sensitive adenosine detection method in early clinical diagnosis and medical research.
研究领域:
生物化学
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医学诊断
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分析化学
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产品关联
DOI
PubMed
高影响因子
AQUACULTURE
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2025
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IF 3.9
Shuai Zhang,Siying Li,Huili Tian,Ming'ao Wang,Mingsheng Lyu,Shujun Wang
Decapod Iridescent Virus 1 (DIV1) leads to high mortality rates in shrimp farming, significantly impacting the aquaculture industry economically. Currently, there are no effective treatments for controlling DIV1 infections, and management primarily relies on preventative measures. Rapid and precise diagnosis of DIV1 is crucial. In this study, we identified two DNA enzymes, MCP-1 and MCP-8, that can specifically recognize DIV1 via in vitro selection. The detection limit of MCP-1 was 6.89 copies/μL of DIV1. We developed a DNAzyme-based “turn off” biosensor for quick detection of DIV1, which is both highly specific and sensitive, by integrating SYBR Green I to enhance the signal. The detection limit of biosensor could reach 2.01 copies/μL of DIV1. Compared to conventional detection methods, this sensor delivers results in 5 min without the need for complex procedures, greatly streamlining the detection process.
研究领域:
分子生物学
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水产养殖学
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病毒学
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DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2020
·
IF 3.99
Si Sun,Qian-Ru Xiao,Cui-Fang Ye,Yong Jiang
Fluorescent nanoparticles have been widely used in the field of biomedical engineering because they are usually biocompatible, cost-effective and homogeneously uniform. In this study, we describe a biomacromolecular fluorescent nanoparticle prepared with a facile disolvating process using bovine serum albumin, DNA segments and SYBR Green I. The obtained co-assemblies, termed [email protected] nanoparticles, had a narrow and relatively uniform size distribution with an average size of about 122 nm and the PDI value 0.087. Cellular uptake results demonstrated well internalization of [email protected] nanoparticles by the Michigan Cancer Foundation-7 (MCF-7) cells. Together with the fluorescent tag of SYBR Green I molecules, [email protected] nanoparticles accumulated in the cell cytoplasm after cellular internalization enabled the MCF-7 cells for fluorescent imaging. This study provided a new strategy for constructing biomacromolecular fluorescent nanoparticles for applications in biomedical engineering and biomedical imaging.
研究领域:
生物医学工程
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分子生物学
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DOI
高影响因子
TALANTA
·
2019
·
IF 4.916
Xuan Wang,Caicheng Long,Xiaoyan Xu,Taiping Qing,Peng Zhang,Bo Feng
Micrococcal nuclease (MNase) is a nonspecific endo-exonuclease that digests single-stranded/double-stranded DNA and RNA. The existence of MNase can serves as an important diagnostic biomarker of Staphylococcus aureus ( S. aureus ) infection. However, most of the substrates in MNase-based sensors are single-stranded DNA, which could also be digested by exonuclease I or S1 nuclease and interfere the MNase detection. In this work, we developed a highly selective fluorescent method for MNase detection using a specific dsDNA and nucleic acid dye SYBR Green I (SGI) as the indicator. After rational design, an AT-rich dsDNA with 3′ protruding termini was screened as the high-specific substrate of MNase assay and efficient enhancer of SGI. The AT-rich dsDNA substrate can resist the digestion of other exonuclease and greatly enhance the fluorescence of SGI. This high-specific substrate-based probe can detect MNase in buffer as well as biological sample with highly selectivity . Moreover, this method was also applied to monitor the MNase secreted by S. aureus . Thus, the proposed MNase-based assay has a strong potential to identify S. aureus in food safety and microbial infection due to its excellent analytical sensitivity and high selectivity.
研究领域:
微生物学
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分子生物学
·
医学诊断
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DOI
PubMed
高影响因子
Analytical Methods
·
2024
·
IF 2.7
Jiangxiong Zhu,Hao Yin,Yang Wang,Lumei Wang,Xueqing Geng,Yun Deng
Cadmium (Cd2+) is a highly toxic heavy metal that can accumulate in the human body through contaminated food and water, posing great health risks. In this study, a label-free fluorescent aptasensor based on SYBR Green I (SGI) for the rapid and sensitive detection of Cd2+ in food samples was designed. The aptasensor utilizes a Cd2+-specific aptamer (Cd-(21)) and its complementary strand (CSCd-(21)) to form a double-stranded DNA (dsDNA) structure in the absence of Cd2+. SGI intercalates into the dsDNA, resulting in a strong fluorescence signal. In the presence of Cd2+, the aptamer undergoes a conformational change, preventing the formation of dsDNA and leading to a decrease in fluorescence intensity. Under optimized conditions, the aptasensor exhibited a linear response to Cd2+ concentrations ranging from 0.11 to 157.37 ng mL−1, with a limit of detection (LOD) of 0.07 ng mL−1. The aptasensor demonstrated high specificity and was successfully applied to detect Cd2+ in fruits and vegetables, with satisfactory recovery rates (95–111%). The proposed aptasensor provides a promising tool for the rapid and sensitive detection of Cd2+ in food.
研究领域:
分析化学
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环境科学
·
食品安全
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产品关联
DOI
PubMed
高影响因子
ANALYTICAL BIOCHEMISTRY
·
2015
·
IF 2.219
Hui Zhang,Congcong Fang,Shijia Wu,Nuo Duan,Zhouping Wang
In this work, a biosensor based on luminescence resonance energy transfer (LRET) from NaYF 4 :Yb,Tm upconversion nanoparticles (UCNPs) to SYBR Green I has been developed. The aptamers are covalently linked to UCNPs and hybridized with their complementary strands. The subsequent addition of SYBR Green allows SYBR Green I to insert into the formed double-stranded DNA (dsDNA) duplex and brings the energy donor and acceptor into close proximity, leading to the fluorescence of UCNPs transferred to SYBR Green I. When excited at 980 nm, the UCNPs emit luminescence at 477 nm, and this energy is transferred to SYBR Green I, which emits luminescence at 530 nm. In the presence of oxytetracycline (OTC), the aptamers prefer to bind to its corresponding analyte and dehybridize with the complementary DNA. This dehybridization leads to the liberation of SYBR Green I, which distances SYBR Green I from the UCNPs and recovers the UCNPs' luminescence. Under optimal conditions, a linear calibration is obtained between the ratio of I 530 to I 477 nm ( I 530 / I 477 ) and the OTC concentration, which ranges from 0.1 to 10 ng/ml with a limit of detection (LOD) of 0.054 ng/ml.
研究领域:
分析化学
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环境科学
·
生物传感器
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产品关联
DOI
PubMed
高影响因子
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