TALANTA
·
2019
·
IF 4.916
Yanli Zhang,Zhenyu Zhu,Xia Teng,Yanqiong Lai,Shaofu Pu,Pengfei Pang,Hongbin Wang,Chun Yang,Colin J. Barrow,Wenrong Yang
Microcystin-LR (MC-LR) is a potent hepatotoxin that is often associated with blooms of cyanobacteria. The analysis of trace MC-LR plays important role in environmental and health fields. Herein, we developed a low-cost and enzyme-free detection method of MC-LR by using hairpin DNA-templated copper nanoclusters (hpDNA-CuNCs) as fluorescent probe . The hpDNA-template was designed and fabricated by a MC-LR aptamer loop and a double strand stem, which can specifically recognize target MC-LR with strong affinity. The AT-rich and complementary double strand stem serves as a template for the formation of CuNCs. The formed fluorescent sensing probe of hpDNA-CuNCs exhibits maximum emission wavelength at 575 nm. Upon the addition of target MC-LR into the hpDNA-CuNCs, we observed fluorescence was quenched considerably due to the high affinity between MC-LR and hpDNA aptamer strand loop, which indicated a conformational change of hairpin probe from the stem-loop DNA structure to single-stranded DNA . Then, the change of fluorescence intensity can be used to monitor the concentration of MC-LR from 0.005 to 1200 μg L −1 with a detection limit of 0.003 ng L −1 . Compared with the previous reports, this method does not require complex DNA sequence design, fluorescence dye label and sophisticated experimental techniques. Moreover, the target MC-LR in real water samples has been detected.
研究领域:
环境科学
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生物化学
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DOI
PubMed
高影响因子
RSC Advances
·
2022
·Vol. 12
·期 21
·13448-13455
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IF 4.036
Wancun Zhang,Pin Zhang,Ying Liang,Weyland Cheng,Lifeng Li,Huanmin Wang,Zhidan Yu,Yan Liu,Xianwei Zhang
Rapid, simple, sensitive and specific approaches for mercury(II) (Hg2+) detection are essential for toxicology assessment, environmental protection, food analysis and human health. In this study, a ratiometric hairpin DNA probe based electrochemical biosensor, which relies on hairpin DNA probes conjugated with water-soluble and carboxyl functionalized quaternary Zn–Ag–In–S quantum dot (QD) on screen-printed gold electrodes (SPGE), referred to as the HP-QDs-SPGE electrochemical biosensor in this study, was developed for Hg2+ detection. Based on the “turn-off” reaction of a hairpin DNA probe binding with a mismatched target and Hg2+ through the formation of T–Hg2+–T coordination, the HP-QDs-SPGE electrochemical biosensor can rapidly quantify trace Hg2+ with high ultrasensitivity, specificity, repeatability and reproducibility. The conformational change of the hairpin DNA probe caused a significant decrease in electrochemical intensity, which could be used for the quantification of Hg2+. The linear dynamic range and high sensitivity of the HP-QDs-SPGE electrochemical biosensor for the detection of Hg2+ was studied in vitro, with a broad linear dynamic range of 10 pM to 1 μM and detection limits of 0.11 pM. In particular, this HP-QDs-SPGE electrochemical biosensor showed excellent selectivity toward Hg2+ ions in the presence of other metal ions. More importantly, this biosensor has been successfully used to detect Hg2+ in deionized water, tap water, groundwater and urine samples with good recovery rate and small relative standard deviations. In summary, the developed HP-QDs-SPGE electrochemical biosensor exhibited promising potential for further applications in on-site analysis.
研究领域:
分析化学
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环境科学
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生物医学工程
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PubMed
高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 7
·1-7
·
IF 5.479
Xu Chengnan,Ying Yibin,Ping Jianfeng
The authors describe a colorimetric method for determination of kanamycin by using gold nanoparticles (AuNPs) as the element of signal-conversion and by applying hybridization chain reaction-assisted signal amplification. The assay is carried out by monitoring the absorbance change and color change adding salt to the reaction solution containing kanamycin (analyte), hairpin DNA probe, and AuNPs. Three hairpin DNA probes with sticky ends were absorbed on the AuNPs via their sticky ends. Cating with DNA prevents them from salt-induced aggregation (which leads to a color change from red to blue) in the complete absence of kanamycin. In contrast, in the presence of kanamycin, the aptamer hairpin DNA probe binds kanamycin, and the newly exposed section of DNA triggers a cascade of hybridization chain reactions with formation of numerous dsDNAs. On addition of salt, the AuNPs form blue aggregates due to the repulsion between dsDNA and AuNPs. Under optimal conditions, the ration of absorbance at 520 and 630 nm drops with the kanamycin concentration in the range from 1 to 40 μM, and the limit of detection is 0.68 μM. The assay can selectively distinguish kanamycin from other antibiotics. The method was applied to kanamycin detection in (spiked) milk samples and gave excellent recoveries.
Schematic presentation of colorimetric method for kanamycin detection using gold nanoparticles modified with hairpin DNA probes and hybridization chain reaction-assisted amplification.
研究领域:
分析化学
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分子生物学
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纳米技术
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PubMed
高影响因子
ANALYTICAL CHEMISTRY
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2015
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IF 5.636
Hui-Fang Cui,Tai-Bin Xu,Yu-Long Sun,An-Wei Zhou,Yu-Han Cui,Wei Liu,John H. T. Luong
Hairpin DNA (hpDNA) as a novel biobarcode was conjugated with gold nanoparticles (AuNPs) and a reporter DNA (rpDNA) to form hpDNA/AuNP/rpDNA nanoparticles for the detection of an oligonucleotide sequence associated with Helicobacter pylori as a model target. The rpDNA is complementary to about a half-portion of the target DNA sequence (tDNA). A capture DNA probe (cpDNA), complementary to the other half of the tDNA, was immobilized on the surface of a gold electrode. In the presence of tDNA, a sandwich structure of (hpDNA/AuNP/rpDNA)/tDNA/cpDNA was formed on the electrode surface. The differential pulse voltammetry (DPV) detection was based on [Ru(NH3)5(3-(2-phenanthren-9-yl-vinyl)-pyridine)]2+, an electroactive complex that binds to the sandwich structure by its intercalation with the hpDNA and the double-stranded DNA (dsDNA) of the sandwich structure. The several factors—high density of biobarcode hpDNA on the surface of AuNPs, multiple electroactive complex molecules intercalated with each hpDNA and dsDNA molecule, and the intercalation binding mode of the electroactive complex with the DNA sandwich structure—contribute to the DNA sensor with highly selective and sensitive sensing properties. The DNA sensor exhibited a detection limit of 1 × 10–15 M (i.e., 1 fM), the DNA levels in physiological samples, with linearity down to 2 × 10–15 M. It can differentiate even one single mismatched DNA from the complementary tDNA. This novel biobarcode-based DNA sensing approach should provide a general platform for development of direct, simple, repetitive, sensitive, and selective DNA sensors for various important applications in analytical, environmental, and clinical chemistry.
研究领域:
生物传感器
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分析化学
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临床医学
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PubMed
高影响因子
RSC Advances
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2018
·Vol. 8
·期 45
·25611-25616
·
IF 2.936
Dan Han,Chunying Wei
In this paper, we construct a fluorescence nucleic acid probe based on DNA-templated silver nanoclusters (DNA-Ag NCs) for the detection of the p53 gene. The fluorescence biosensing of the “turn-on” model is successfully implemented as a result of the target-triggered configurational change in the hairpin DNA probe and the synthesis of fluorescent Ag NCs. With this biosensor, the limit of detection (LOD) for the p53 gene is 3.57 nM and the linear range is 250–2500 nM in phosphate buffer solution, while a LOD of 6.06 nM in the linear range of 250–2500 nM is obtained in 1% diluted fetal calf serum. So this probe, with its advantages of specificity, practical application, easy operation and low cost, will have favourable development prospects in biological sensing and imaging.
研究领域:
生物化学
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分子生物学
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纳米生物学
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PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2015
·
IF 5.636
Jingpu Zhang,Chao Li,Xiao Zhi,Gabriel Alfranca Ramón,Yanlei Liu,Chunlei Zhang,Fei Pan,Daxiang Cui
MicroRNA (miRNA) biomarkers display great potential for cancer diagnosis and prognosis. The development of rapid and specific methods for miRNA detection has become a hotspot. Herein, hairpin DNA-templated silver nanoclusters (AgNCs/HpDNA) were prepared and integrated into strand-displacement amplification (SDA) as a novel beacon for miRNA detection. The light-up platform was established based on guanine (G)-rich fluorescence enhancement that essentially converted the excitation/emission pair of AgNCs/HpDNAs from a shorter wavelength to a longer wavelength, and then achieved fluorescent enhancement at longer wavelength. On the basis of the validation of the method, the single and duplex detection were conducted in two plasma biomarkers (miR-16-5p and miR-19b-3p) for the diagnosis of gastric cancer. The probe (AgNCs/RED 16(7s)C) utilized for miR-16-5p detection adopted a better conformation with high specificity to recognize single-base mismatches by producing dramatically opposite signals (increase or decrease at 580 nm ex/640 nm em) while the probe (AgNCs/GRE 19b(5s)C) for miR-19b-3p generated dual signals (increase at 490 nm ex/570 nm em and decrease at 430 nm ex/530 nm em) with bright fluorescence in one reaction during the amplification, but unexpectedly was partially digested. This is for the first time to allow the generation of enhanced fluorescent AgNCs and the target recognition integrated into a single process, which offers great opportunity for specific miRNA detection in an easy and rapid way.
研究领域:
生物化学
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分子生物学
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癌症研究
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纳米技术
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DOI
PubMed
高影响因子
ACS Sensors
·
2021
·
IF 7.711
Guangyu Tao,Xiao Xu,Rong Sheng Li,Feng Liu,Na Li
Restriction endonucleases (ENases) and DNA methyltransferases (MTases) are important enzymes in biological processes, and detection of ENases/MTases activity is significant for biological and pharmaceutical studies. However, available nonamplification methods with a versatile design, desirable sensitivity, and signal production mode of unbiased quantification toward multiple nucleases are rare. By combining deliberately designed hairpin DNA probes with the colocalized particle counting technique, we present a nonamplification, separation-free method for multiplexed detection of ENases and MTases. In the presence of target ENases, the hairpin DNA is cleaved and the resulting DNA sequence forms a sandwich structure to tie two different-colored fluorescent microbeads together to generate a colocalization signal that can be easily detected using a standard fluorescence microscope. The multiplexed assay is realized via different color combinations. For the assay of methyltransferase, methylation by MTases prevents cleavage of the hairpin by the corresponding ENase, leading to decreased colocalization events. Three ENases can be simultaneously detected with high selectivity, minimal cross-talk, and detection limits of (4.1–6.4) × 10–4 U/mL, and the corresponding MTase activity can be measured without a change of the probe design. The potential for practical application is evaluated with human serum samples and different ENase and MTase inhibitors with satisfactory results. The proposed method is separation-free, unbiased toward multiple targets, and easy to implement, and the strategy has the potential to be extended to other targets.
研究领域:
生物化学
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分子生物学
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分析化学
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DOI
PubMed
高影响因子
ANALYST
·
2019
·Vol. 144
·期 13
·4081-4085
·
IF 4.019
Yuan-Min Liu,Xiu-Yu Fang,Fang Fang,Zhi-Yong Wu
Chelerythrine (CHE) is one of the potential drugs for cancer treatments. The interaction between hairpin DNA and CHE has been investigated by spectral and mass spectrometry methods. In this paper, the stability of hairpin DNA with different loop bases and its interaction with CHE were explored with a single α-hemolysin (α-HL) nanopore sensing interface. The results showed that the characteristic current pulses not only relate to the loop composition changes of the hairpin DNA, but also provide interaction information between CHE and the hairpin DNA molecules. The dwell time of current pulses for hairpin DNA was significantly increased (hundreds of ms) due to the addition of CHE, and two characteristic current distributions were recognized for the hairpin with T3 and C3 loops. The two characteristic current groups could be ascribed to the hairpin DNA and the ones with CHE. This study indicates that it is possible to study the interaction between single CHE and single hairpin DNA molecules by the single-nanopore sensing interface as an alternative method to conventional spectrometric methods for therapeutic mechanism and drug screening purposes.
研究领域:
生物物理
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分子生物学
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纳米技术
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癌症研究
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2020
·
IF 6.306
Mei Liu,Zongqi Yang,Baoxin Li,Jianxiu Du
A colorimetric aptasensing strategy for detection of kanamycin was designed based on aptamer biorecognition and signal amplification assisted by nicking enzyme. The aptamer of kanamycin was designed to be contained in the metastable state hairpin DNA. The target DNA as recycling DNA was located in the loop of hairpin DNA. The presence of kanamycin stimulates the continuous actions, including specific recognition of the aptamer to kanamycin, the hybridization between target DNA and signal probe, the cleavage function of nicking enzyme. The actions induced accumulation of numerous free short sequences modified by platinum nanoparticles (PtNPs), which can catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB)-H 2 O 2 to produce a colorimetric response. The aptasensor exhibited good selectivity and sensitivity for kanamycin in milk with a detection limit as low as 0.2 pg·mL −1 . In addition, the proposed assay is potentially to be extended for other antibiotics detection in foods by adapting the corresponding aptamer sequence.
研究领域:
分析化学
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生物传感器
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食品安全
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分子生物学
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DOI
PubMed
高影响因子
International Journal of Nanomedicine
·
2023
·
IF 8
Dawei Deng,Yang Li,Jianpeng Xue,Jie Wang,Guanhua Ai,Xin Li,Yueqing Gu
Messenger RNA (mRNA), a single-strand ribonucleic acid with functional gene information is usually abnormally expressed in cancer cells and has become a promising biomarker for the study of tumor progress. Hairpin DNA-coated gold nanoparticle (hDAuNP) beacon containing a bare gold nanoparticle (AuNP) as fluorescence quencher and thiol-terminated fluorescently labeled stem–loop–stem oligonucleotide sequences attached by Au–S bond is currently a new nanoscale biodiagnostic platform capable of mRNA detection, in which the design of the loop region sequence is crucial for hybridizing with the target mRNA. Hence, in this study, to improve the sensitivity and selectivity of hDAuNP beacon simultaneously, the loop region of hairpin DNA was screened by bioinformatics strategy. Here, signal transducer and activator of transcription 5b (STAT5b) mRNA was selected and used as a practical example. The results from the combined characterizations using optical techniques, flow cytometry assay, and cell microscopic imaging showed that after optimization, the as-prepared hDAuNP beacon had higher selectivity and sensitivity for the detection of STAT5b mRNA in living cells, as compared with our previous beacon. Thus, the bioinformatics method may be a promising new strategy for assisting in the designing of the hDAuNP beacon, extending its application in the detection of mRNA expression and the resultant mRNA-based biological processes and disease pathogenesis.
研究领域:
纳米技术
·
分子生物学
·
生物信息学
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癌症研究
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DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2020
·
IF 10.257
Chengxi Zhu,Dong Liu,Yuye Li,Shuai Ma,Meng Wang,Tianyan You
The simultaneous detection of multiple mycotoxins in grains is significant due to the enhanced toxicity induced by their synergistic effects . In this work, a dual-ratiometric electrochemical aptasensing strategy for the simultaneous detection of aflatoxin B1 (AFB1) and ochratoxin A (OTA) was developed. Here, an anthraquinone-2-carboxylic acid (AQ)-labelled complementary DNA (cDNA) was used to provide separate and specific binding sites to assemble the ferrocene-labelled AFB1 aptamer (Fc-Apt1) and methylene blue-labelled OTA aptamer (MB-Apt2). The target-induced current ratios of I Fc /I AQ and I MB /I AQ were then used to quantitatively relate to AFB1 and OTA, respectively. Following this principle, two types of aptasensors involving the hairpin DNA (hDNA) and linear single-stranded DNA (ssDNA) as the cDNA were fabricated for performance comparisons. The results revealed that hairpin DNA with a rigid 2D structure can greatly improve the assembly and recognition efficiency of the sensing interface, which makes the hDNA-based aptasensor possess high sensitivity, reliability and anti-interference ability. The hDNA-based aptasensor exhibited a detection range of 10-3000 pg mL −1 for AFB1 and 30-10000 pg mL −1 for OTA, respectively, with no observable cross-reactivity. Furthermore, the aptasensor was applied to analyze corn and wheat samples, and the reliability was validated by HPLC-MS/MS. Our work has presented a novel way for fabricating a high-performance aptasensor for simultaneous detection of multiple mycotoxins .
研究领域:
食品安全
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分析化学
·
生物传感技术
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DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 10
·7765-7771
·
IF 3.289
Ruipeng Hou,Xiaoqing Niu,Fengling Cui
A highly sensitive and selective label-free biosensor was designed for DNA determination based on target-induced opening of the hairpin DNA and forming a G-quadruplex with protoporphyrin IX (PPIX) as a signal reporter. In the absence of target-DNA (T-DNA), the probe-DNA (P-DNA) forms a hairpin structure. A G-rich sequence in the strand is partially caged in the stem-loop structure and cannot fold into a G-quadruplex. In the presence of T-DNA, the specific combination of targets with the sensing sequence (loop sequence) triggers the release of the G-rich sequence and allows it to fold properly and bind with PPIX resulting in the fluorescence of the G-quadruplex–PPIX providing the readout signal for the sensing event (detection limit of 3.5 nM). Based on the higher efficiency of Pb2+ at stabilizing G-quadruplexes than K+ and the Pb2+-stabilized G-quadruplexes not binding to PPIX, which resulted in fluorescence decrease, the proposed DNA-sensing system can be further exploited as a Pb2+-sensing method. The detection limit for Pb2+ is 2.6 nM.
研究领域:
分析化学
·
生物化学
·
环境科学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）