SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
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2023
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IF 4.4
Boxu Wang,Zheng Liu,Zhihong Li,Ningyi Xu,Xuejiao Zhang,Ruifang Su,Junyang Wang,Rui Jin,Chunyan Sun
Hg 2+ is highly toxic to human health and ecosystem. In this work, based on the unique fluorescent property of 2-Aminopurine (2-AP), the formation of T-Hg 2+ -T mismatch structure and the signal amplification of exonuclease III (Exo III) assisted target cycle, a fluorescent probe for facile and sensitive detection of Hg 2+ is constructed. The hairpin-looped DNA probe is rationally designed with 2-AP embedded in the stem and thymine-rich recognition overhangs extended at the termini. The cleavage of the double stranded DNA stem with stable T-Hg 2+ -T pairs catalyzed by Exo III is prompted to happen upon recognition of trace Hg 2+ . Under the optimal reaction conditions, there is an excellent linear relationship between Hg 2+ concentration and fluorescence intensity in the range of 7.5–200 nM with a detection limit of 0.38 nM. In addition, the detection results of Hg 2+ in Songhua River water and fish samples are satisfactory. The fluorescent probe avoids labeling additional quenchers or quenching materials and has strong anti-interference ability. Thus, the fluorescent probe has a broad prospect in practical application.
研究领域:
生物化学
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环境科学
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PubMed
高影响因子
Analytical Methods
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2023
·Vol. 16
·期 4
·576-582
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IF 3.1
Fangfang Yang,Shuang Li,Jialiang Wu,Shufeng Liu
Reversible structural changes in DNA nanomachines have great potential in the field of bioanalysis. Here, we demonstrate an assembly strategy for quencher-free and tunable DNA tweezers based on 2-aminopurine (2-AP), avoiding the tedious fluorescence labelling step. The conformational state of the tweezers could be controlled by specific oligonucleotides (fuel or anti-fuel). Taking advantage of the local environmental sensitivity of 2-AP, the structural changes of the tweezers were easily tracked, and multiple cyclic switching of the tweezers between the open and closed states was achieved. In addition, the influence of oligonucleotide structure on the fluorescence properties of 2-AP was deeply explored. We figured out that the fluorescence of 2-AP was highly quenched by the base-stacking of natural bases in DNA oligonucleotides. Moreover, by comprehensively regulating the type of bases surrounding the inserted 2-AP site, a sensitive fluorescence response towards dynamic change can be obtained. This principle of quencher-free nanodevices based on 2-AP provides a convenient method for monitoring the structural changes of DNA nanomachines.
研究领域:
生物化学
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纳米技术
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分子生物学
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PubMed
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
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2019
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IF 2.931
Yanhua He,Youwei Yu,Xiaoye Wen,Yan Shi,Jianhu Wu,Zhengping Guan,Meilin Cui,Chunling Xiao
A sensitive, efficient and quencher-free fluorescence aptasensor to detect Ochratoxin A (OTA) based on aptamer , 2-aminopurine (2AP) labeled Oligonucleotide sequence, as well as exonuclease I (Exo I) activity was developed. In which the aptamer specific to OTA was modified into a hairpin structure, and 8 bases at the 3′ ends are exposed (H); also, 2AP is embedded in the oligonucleotide complementary to the 8 bases (2AP-probe).The detection principle based on 2AP-probe could be bonded to its complementary sequence and quenches the fluorescence of 2AP; The aptamer has a stronger affinity for the target than its complementary sequence; Exo I can dissociate single-stranded DNA and has little effect on double-stranded DNA as well as folded DNA. In the absence of OTA, the fluorescence of 2AP is quenched due to the complementary pairing of H and 2AP-probe; in the presence of OTA, H selective binding target is detached from 2AP-probe, and the fluorescence of 2AP is slightly restored. Moreover, when the Exo I is added to the detection system, 2AP-probe is dissociated by the Exo I to release the free 2AP, and the fluorescence of the system is further enhanced thereby realizing the detection of OTA. The detection limit of the aptasensor was low as 0.03 nM with a linear range of 0.5–100 nM. Moreover, the aptasensor has good selectivity and practicability and also has good potential in realizing the detection of toxic and harmful substances in food complex matrices.
研究领域:
食品科学
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分子生物学
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PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2017
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IF 5.401
Haiyan Liu,Yunfeng Bai,Jun Qin,Haiyan Wang,Yuzhen Wang,Zezhong Chen,Feng Feng
A novel sensitive fluorescence method was developed for adenosine detection by using adenosine aptamer, Exo I and a 2-aminopurine-modified DNA (2-AP probe). 2-AP probe was completely complementary to adenosine aptamer. This strategy took advantage of the high binding affinity of adenosine aptamer and the susceptibility of 2-aminopurine (2-AP) to the local base stacking environment. In the absence of the adenosine, the formation of double-stranded DNA (dsDNA) through the hybridization of the aptamer with the 2-AP probe prevented the digestion of 2-AP probe by Exo I. The fluorescence of 2-AP was significantly quenched due to the base-stacking interaction. In the presence of adenosine, the binding of adenosine with the aptamer prevented the hybridization between aptamer and 2-AP probe, leading to the digestion of 2-AP probe by Exo I and the release of 2-AP. The fluorescence was recovered. A limit of detection of 0.30 μM and a linear range from 10 μM to 600 μM ( R 2 = 0.9933) were achieved by this assay. Moreover, adenosine analogs did not produce any significant change in the fluorescence intensity response, indicating good selectivity of this sensor for adenosine detection. Finally, it was used for the diluted serum sample.
研究领域:
分析化学
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分子生物学
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生物技术
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高影响因子
JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES
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2025
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IF 2.8
Yi Yan,Zifang Peng,Luyan Meng,Wenfen Zhang,Chuan-Fan Ding,Shusheng Zhang
Clarifying the pathogenesis of diabetes contributes to prevent the occurrence of diabetes. Glycosylated proteins carried by serum exosomes are possibly used as biomarkers of some diseases. In this work, a novel hydrophilic carbonaceous sphere was prepared via one-step hydrothermal carbonization (HTC) process by using glucose as raw material, 1,2-epoxy-5-hexene as a linker, 2-aminopurine as hydrophilic functional group, water as the sole solvent (denoted as CS@2AP). The synthesis process was simple and eco-friendly. The obtained CS@2AP proposed high sensitivity (0.08 fmol μL −1 ) and excellent selectivity (1:1000) for glycopeptides enrichment. Moreover, CS@2AP displayed good isolation effect for serum exosomes from diabetes patient analyzed by western blot. Furthermore, when CS@2AP was used for glycopeptides analysis from exosome digests, 68 glycopeptides were specifically captured.
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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糖尿病研究
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生物材料
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PubMed
高影响因子
APPLIED SURFACE SCIENCE
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2019
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IF 5.155
Meng Tian,Zhenhua Li,Ruihong Song,Yingxian Li,Chengang Guo,Yujie Sha,Wanling Cui,Shicai Xu,Guodong Hu,Jihua Wang
Guanine riboswitch (GR) is located in the untranslated region of mRNA that performs important biological functions by interactions with specific ligand molecules. The present standard methods for detecting mRNA has been widely used, but suffer from extra labeling steps, high cost, low throughput, low sensitivities and limited dynamic ranges. The field effect transistor (FET) biosensors showed high performance in detecting a large number of biological analytes. However, the detection of analytes with low charge and small molecule still remains a challenge. In this paper, a label-free graphene field effect transistor (G-FET) biosensor has been developed to detect the binding interactions between GR and four purine analog ligand molecules (GUA, 6GU, 2BP, XAN). We demonstrated that the G-FET biosensor were highly sensitive in detecting the electric-neutral and low molecular weight ligands by using GR as probe. The sensing mechanisms for electric-neutral molecule is revealed by molecular dynamics simulation. The equilibrium dissociation constants K D and binding free energy Δ G of GR-GUA, GR-6GU, GR-2BP and GR-XAN were obtained by the G-FET biosensor, and the results are comparable with the calculated by molecular dynamics simulation and previous reports. We demonstrated that the G-FET biosensor can be used as affinity biosensors to quantify biomolecular interactions.
研究领域:
生物物理学
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分子生物学
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纳米技术
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DOI
高影响因子
危险品化学品经营许可证（带存储）