FOOD CHEMISTRY
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2020
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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
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
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2017
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IF 4.95
Zewei Luo,Yimin Wang,Xiaoyong Lu,Junman Chen,Fujing Wei,Zhijun Huang,Chen Zhou,Yixiang Duan
Antibiotic abuse has been bringing serious pollution in water, which is closely related to human health. It is desirable to develop a new strategy for antibiotic detection. To address this problem, a sensitive fluorescent aptasensor for antibiotic detection was developed by utilizing gold nanoparticles modified magnetic bead composites (AuNPs/MBs) and nicking enzyme . AuNPs/MBs were synthesized with the help of polyethylenimine (PEI). The prepared AuNPs/MBs acted as dual-functional scaffolds that owned excellent magnetic separation capacity and strong covalent bio-conjugation. The non-specifically absorbed aptamers in AuNPs/MBs were less than that in MBs. Hence, the fluorescent aptasensor based on AuNPs/MBs show a better signal to background ratio than that based on carboxyl modified magnetic beads (MBs). In this work, ampicillin was employed as a model analyte . In the presence of ampicillin, the specific binding between ampicillin and aptamer induced structure-switching that led to the release of partial complementary DNA (cDNA) of aptamer. Then, the released cDNA initiated the cycle of nicking enzyme assisted signal amplification (NEASA). Therefore, a large amount of taqman probes were cleaved and fluorescence signal was amplified. The prepared fluorescent aptasensor bring sensitive detection in range of 0.1–100 ng mL −1 with the limit of detection of 0.07 ng mL −1 . Furthermore, this aptasensor was also successfully applied in real sample detection with acceptable accuracy. The fluorescent aptasensor provides a promising method for efficient, rapid and sensitive antibiotic detection.
研究领域:
生物技术
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环境科学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
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2017
·
IF 4.95
Xuejun Cui,Rongguo Li,Xiaofei Liu,Jingfeng Wang,Xueqi Leng,Xiaolei Song,Qianqian Pei,Yu Wang,Su Liu,Jiadong Huang
Herein, we have reported the development of a simple, rapid, and low cost colorimetric method for the detection of antibiotic based on target-activated split peroxidase DNAzyme coupled with dual nicking enzyme signal amplification (NESA). To lower background signal in G-quadruplex DNAzyme-based detection, the two split G-rich parts are caged into two different hairpin probes, respectively, preventing the two parts from assembling into the G-quadruplex structure. By the combination of restriction endonuclease-assisted cleavage reaction with the spilt G-quadruplex probes, target-modulated release of the two split G-rich parts is achieved, affording high specificity of antibiotic detection. Our strategy features with several aspects. First, the less background signal produced by the self-assembly of G-quadruplex in the absence of target is effectively eliminated owing to the pre-blocking of the two split G-rich parts. Second, dual NESA coupled G-quadruplex DNAzyme amplification strategy is integrated with colorimetric assay of antibiotic, which significantly improves the detection sensitivity. Third, peroxidase-mimicking DNAzyme is used as biocatalyst in our reaction system, which can catalyze the oxidation of 2,2' - azino - bis (3 - ethylbenzothiozoline - 6 - sulfonic acid) (ABTS 2− ) mediated by H 2 O 2 to generate the colored radical anion (ABTS •- ), allowing to low cost and visual detection of antibiotic by the naked eye. Under optimized conditions, the results revealed the proposed biosensor exhibits excellent specificity and sensitivity toward kanamycin with a detection limit as low as 14.7 pM. Hence, the target-activated split G-quadruplex DNAzyme and dual NESA-based strategy provides a useful and practical platform for antibiotic residues determination and other analytes detection in bio-analysis.
研究领域:
生物化学
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分析化学
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生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
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2019
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IF 9.518
Ruo-Nan Zhao,Li-Ping Jia,Zhe Feng,Rong-Na Ma,Wei Zhang,Lei Shang,Qing-Wang Xue,Huai-Sheng Wang
8-Hydroxy-2′-deoxyguanosine (8-OH-dG) is a principal stable marker of DNA oxidative damage . Sensitive and specific detection of 8-OH-dG is of great importance for early disease diagnosis. In this paper, we developed an electrochemiluminescence aptasensor for 8-OH-dG detection based on target induced multi-DNA release and nicking enzyme signaling amplification strategy. First, three kinds of short DNAs were aligned on the aptamers immobilized on the magnetic beads. In the presence of 8-OH-dG, the aptamer recognized and specifically bound with 8-OH-dG, leading to the release of three kinds of short DNAs and three-fold signal amplification . Then the released short DNAs hybridized with ferrocence (Fc) labeled hairpin DNA (Fc-HP) immobilized on the gold electrode to form a double strand DNA. Subsequently, nicking endonuclease (Nt. Alw I) recognized the asymmetric sequence in the dsDNA and cleaved the substrate strand (Fc-HP) into two parts, one fragments containing Fc would leave the surface of electrode. Based on the quenching effect of Fc on the electrochemiluminescence (ECL) of Ru(bpy) 3 2+ /TPA, a signal-on ECL aptasensor was developed. At the same time, three kinds of short DNAs were released again and reused to initiate the repeated cycles of hybridization-cleavage. Under double signal amplification, this aptasensor achieved a low detection of 25 fM and a wide linear range from 100 fM to 10 nM for 8-OH-dG. Besides, the amount of 8-OH-dG in urine samples derived from different people were determined with satisfactory results.
研究领域:
生物化学
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分析化学
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医学诊断
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
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2014
·
IF 5.825
Lu Li,Qian Wang,Jie Feng,Lili Tong,Bo Tang
Membrane proteins play vital roles in numerous physiological functions. Recently, they have been considered as candidate biomarkers for cancer and recognized as major drug targets. So, accurate, sensitive, and high-throughput quantitative detection of the membrane proteins is crucial for better understanding their roles in cancer cells and further validating their function in clinical research. Here, we report a highly sensitive and homogeneous detection of membrane protein on single living cells by aptamer and nicking enzyme assisted fluorescence signal amplification in microfluidic droplets. The homogeneous reaction based on the membrane protein-triggered conformation alteration of hairpin probe can improve the detection accuracy with elimination of several washing and separation steps. The microfluidic system provides a high-throughput platform for the detection of a single cell, and the highly monodisperse droplet can function as an independent microreactor for the aptamer and nicking enzyme assisted fluorescence signal amplification, coordinating with the small volume of the confined space (a droplet), increased reaction rate, and highly sensitive detection of membrane protein on single cell can be reached.
研究领域:
生物技术
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分子生物学
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癌症研究
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2020
·
IF 7.1
Xiaoyan Zhang,Tingting Wu,Yuemeng Yang,Yongqiang Wen,Shutao Wang,Li-Ping Xu
Superwettable microchips exhibit excellent ability to anchor microdroplets and great potential in ultratrace sample detection. Herein, we present a superwettable electrochemical biosensor based on a dual-DNA walker strategy (dual-DW biosensor) for the attomolar detection of food-borne microorganisms ssDNA in microdroplets. In the presence of the target E. coli O157: H7 ssDNA, the blocked walking probe is activated as the first-step DNA walker. With the aid of the Nt.BsmAI nicking endonuclease, the partial sequence of the basal probe was released, thus achieving the first-step signal amplification. Then the hairpin probe 1(H1) was opened by the released basal probe and followed by the autonomous strand displacement of the ferrocene (Fc) labeled hairpin probe 2 (H2) and movement of the basal probe. Under optimized conditions, the dual-DNA walker strategy finally renders the dual-DW biosensor an ultrahigh sensitivity of 30 aM toward E. coli O157: H7 ssDNA and a broad detection linear range. The dual-DW biosensor also enables successful analysis of trace amount of E. coli O157: H7 ssDNA in real food samples. The superwettable electrochemical biosensor based on a dual-DNA walker strategy is expected to be a versatile tool for ultratrace DNA detection and be promising in food analysis.
研究领域:
生物化学
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分析化学
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食品科学
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分子生物学
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2024
·
IF 8
Di Liu,Xuelian Chen,Yaping Li,Guiping Sun,Jingwen Gao,Hailiang Nie,Cuiping Li
The abuse of 17β-estradiol (E2) in breeding and the excretion into the environment by human beings result in exposure of E2 to humans. Excessive levels of E2 can cause an adverse effect on the human endocrine systems. Therefore, an efficient and sensitive method for the analysis of E2 is required. Herein, based on the specific capture of aptamer, the digestion of Exonuclease III, and efficient amplification of isothermal exponential amplification reaction (EXPAR), a highly sensitive and selective strategy is established for E2 analysis. E2 binds to the aptamer due to their high affinity, preventing the complementary DNA (cDNA) of the aptamer from hybridizing with it. Thus, the cDNA remains unbound and freely available in the solution. Then, Exonuclease III digests the cDNA-aptamer complex, leaving the free cDNA intact. cDNA serves as primers to trigger EXPAR with the help of Bst 2.0 WarmStart DNA polymerase and Nt.BstNBI nicking enzyme, achieving sensitive detection of E2. Without E2, cDNA hybridizes with the aptamer to form double-stranded DNA, which is degraded by Exonuclease III. As a result, the amplification reaction fails to initiate. The approach shows a linear range of 100 aM-10 pM, spanning 5 orders of magnitude, with the limit of detection as low as 36 aM. In addition, the selectivity and reproducibility are great, and the recoveries in tap water and milk ranges from 99.4 % to 117.3 %, suggesting good practicability. This method may also provide a new possibility for sensitive detection of other small-molecule targets via using the corresponding aptamers.
研究领域:
分析化学
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生物化学
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环境科学
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分子生物学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）