Food Bioscience
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2024
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IF 4.8
Zixuan Shang,Pengfei Ma,Imran Mahmood Khan,Ningru Yang,Zhouping Wang
Currently, the technology for detecting antibiotics is developing rapidly, with good sensitivity and selectivity. However, some detection methods still have issues with cumbersome pretreatment and high experimental costs. Herein, A “turn-off” bifunctional DNA tweezer was constructed through the design of DNA sequence and self-assembly technology for the dual detection of Enrofloxacin (ENR) and Kanamycin (KANA) in a food matrix. The operation is simple, which increases the detection speed and reduces the detection cost. The two ends of the bifunctional DNA tweezers are connected with specific split aptamer sequences, and the split aptamer forms a specific ternary complex with the target. The tweezers “clip” ENR and KANA at their respective ends, causing a structural change. Under the optimal experimental conditions, the linear range of detection ENR is 0.2 ng/mL-1000 ng/mL with an LOD of 0.18 ng/mL, the linear range of detection KANA is 0.5 ng/mL-1000 ng/mL with an LOD of 0.36 ng/mL. The bifunctional DNA tweezers involved provide a new idea for the construction of DNA nanomachines, which is also suitable for the recognition and detection of other small molecules.
研究领域:
生物化学
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食品科学
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纳米技术
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DOI
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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DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
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2021
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IF 6.986
Jia-Yang He,Xin Shang,Chun-Li Yang,Si-Yu Zuo,Ruo Yuan,Wen-Ju Xu
Exploring the ratiometric fluorescence biosensing of DNA-templated biemissive silver nanoclusters (AgNCs) is significant in bioanalysis, yet the design of a stimuli-responsive DNA device is a challenge. Herein, using the anti-digoxin antibody (anti-Dig) with two identical binding sites as a model, a tweezer-like DNA architecture is assembled to populate fluorescent green- and red-AgNCs (g-AgNCs and r-AgNCs), aiming to produce a ratio signal via specific recognition of anti-Dig with two haptens (DigH). To this end, four DNA probes are programmed, including a reporter strand (RS) dually ended with a g-/r-AgNC template sequence, an enhancer strand (ES) tethering two same G-rich tails (G18), a capture strand (CS) labeled with DigH at two ends, and a help strand (HS). Initially, both g-AgNCs and r-AgNCs wrapped in the intact RS are nonfluorescent, whereas the base pairing between RS, ES, CS, and HS resulted in the construction of DNA mechanical tweezers with two symmetric arms hinged by a rigid “fulcrum”, in which g-AgNCs are lighted up due to G18 proximity (“green-on”), and r-AgNCs away from G18 are still dark (“red-off”). When two DigHs in proximity recognize and bind anti-Dig, the conformation switch of these tweezers resultantly occurs, taking g-AgNCs away from G18 for “green-off” and bringing r-AgNCs close to G18 for “red-on”. As such, the ratiometric fluorescence of r-AgNCs versus g-AgNCs is generated in response to anti-Dig, achieving reliable quantization with a limit of detection at the picomolar level. Based on the fast stimulated switch of unique DNA tweezers, our ratiometric strategy of dual-emitting AgNCs would provide a new avenue for a variety of bioassays.
研究领域:
生物分析
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纳米生物学
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分子诊断
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产品关联
DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
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2024
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IF 5.7
Yingao Yang,Zixuan Zhou,Yifen Guo,Ruipeng Chen,Daoming Tian,Shuyue Ren,Huanying Zhou,Zhixian Gao
Background DNA tweezers, classified as DNA nanomachines, have gained prominence as multifunctional biosensors due to their advantages, including a straightforward structure, response mechanism, and high programmability. While the DNA tweezers demonstrate simultaneous, rapid, and stable responses to different targets, their detection sensitivity requires enhancement. Some small molecules , such as mycotoxins , often require more sensitive detection due to their extremely high toxicity. Therefore, more effective signal amplification strategies are needed to further enhance the sensitivity of DNA tweezers in biosensing. Results We designed programmable DNA tweezers that detect small-molecule mycotoxins and miRNAs through simple sequence substitution. While the DNA tweezers demonstrate simultaneous, rapid, and stable responses to different targets, their detection sensitivity requires enhancement. We introduced the Strand Displacement Amplification (SDA) technique to address this limitation, proposing a strategy of novel programmable DNA tweezers-SDA ultrasensitive signal amplification fluorescence sensing . We specifically investigate the effectiveness of this approach concerning signal amplification for two critical mycotoxins: aflatoxin B1 (AFB1) and zearalenone (ZEN). Results indicate that the detection ranges of AFB1 and ZEN via this strategy were 1–10,000 pg mL −1 and 10–100,000 pg mL −1 , respectively, with corresponding detection limits of 0.933 pg mL −1 and 1.07 pg mL −1 . Compared with the DNA tweezers direct detection method for mycotoxins, the newly constructed programmable DNA tweezers-SDA fluorescence sensing strategy achieved a remarkable 10 4 -fold increase in the detection sensitivity for AFB1 and ZEN. Significance The constructed programmable DNA tweezers-SDA ultrasensitive signal-amplified fluorescence sensing strategy exhibits excellent detection performance for mycotoxins. The superb versatility of this strategy allows the developed method to be easily used for detecting other analytes by simply replacing the aptamer and cDNA, which has incredible potential in various fields such as food safety screening, clinical diagnostics, and environmental analysis .
研究领域:
生物传感器
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纳米技术
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分析化学
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食品安全
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环境分析
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临床诊断
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DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）