ANALYST
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2018
·Vol. 143
·期 21
·5295-5301
·
IF 3.864
Guobin Mao,Mingyuan Du,Xinxin Wang,Xinghu Ji,Zhike He
In this work, a simple and novel ratiometric fluorescence method based on ROX-DNA-functionalized CdZnTeS quantum dots (QDs) was developed for the detection of dopamine (DA) and tyrosinase (TYR). A ratiometric fluorescent probe was constructed by binding phosphorothioate DNA to the metal ions of QDs, which is a modification-free and low-cost method. DA was easily oxidized to DA quinone under the catalysis of TYR by dissolved O2, which effectively quenched the fluorescence of the QDs. Strong linear correlations were achieved for TYR in the range of 10.0–100.0 ng mL−1 and for DA in the range of 10.0–1000.0 nM. The limit of detection was estimated to be as low as 1.05 ng mL−1 for TYR and 1.93 nM for DA. Moreover, various colors were displayed in the course of detection, which could be observed by the naked eye. Therefore, an on-site and sensitive fluorescence method for the visual detection of DA and TYR can be developed. In addition, the findings revealed the potential applicability of the ratiometric fluorescent probe for the detection of DA and TYR in human serum. This ratiometric fluorescence method is not only sensitive and selective but also rapid and convenient for the detection of the analytes without sophisticated instrumentation.
研究领域:
分析化学
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生物化学
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分子生物学
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高影响因子
ANALYTICAL CHEMISTRY
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2017
·
IF 6.32
Guobin Mao,Qin Cai,Fubing Wang,Changliang Luo,Xinghu Ji,Zhike He
As the blood glucose concentration is an important clinical parameter of diabetes, the rapid and effective detection of blood glucose is very significant for monitoring and managing diabetes. Here, a facile method to prepare Rox-DNA functionalized CdZnTeS quantum dots (QDs) was developed. The Rox-DNA functionalized CdZnTeS QDs were prepared by a one-pot hydrothermal method through phosphorothioate DNA bound to QDs, which were employed as a ratiometric fluorescent probe for the rapid and sensitive detection of H2O2 and glucose. Compared with the traditional multistep construction of ratiometric fluorescent probes, this presented approach is simpler and more effective without chemical modification and complicated separation. The CdZnTeS QDs with green fluorescence is specifically sensitive to H2O2, while the red fluorescence of Rox is invariable. H2O2 is the product from the oxidation of glucose catalyzed by glucose oxidase (GOx). Therefore, a facile method to detect H2O2 and glucose with a detection limit of 0.075 μM for H2O2 and 0.042 μM for glucose was developed. In addition, this proposed probe has been employed for the detection of glucose in human serum with a satisfactory result. Moreover, this probe has been used for visual detection, and the health and diabetics can be distinguished by the naked eye. Meanwhile, this nanoprobe is also generalizable and can be extended to the detection of many other H2O2-mediated analytes.
研究领域:
生物化学
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医学诊断
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纳米技术
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高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2018
·
IF 5.667
Guobin Mao,Wenquan Peng,Songbai Tian,Jiao Zheng,Xinghu Ji,Zhike He
Herein, we developed a simple and sensitive method for the detection of protamine and trypsin by using a ratiometric fluorescent probe based on Rox-DNA functionalized CdZnTeS quantum dots (QDs). The Rox-DNA functionalized CdZnTeS QDs were prepared via one-pot method, which was simple, low-cost, and modification-free. Protamine can cause the aggregation of ratiometric fluorescent probe through electrostatic interaction and quench the fluorescence of CdZnTeS QDs. Then, the protamine could be hydrolyzed to small peptides by trypsin and the fluorescence of QDs was recovered. However, the fluorescence of Rox kept unchanged. The fluorescence intensity ratio was proportional to the concentration of protamine or trypsin. A good linear relationship (25–300 ng/mL for protamine and 2.5–50 ng/mL for trypsin) with low limit of detection (4.73 ng/mL for protamine and 0.87 ng/mL for trypsin) was obtained. Meanwhile, we observed different colors by the naked eye after the addition of different concentrations of protamine and trypsin, and the minimum detectable concentration was as low as 4 μg/mL for protamine and 40 ng/mL for trypsin, respectively. In addition, the ratiometric fluorescent probe exhibited good analytical performance in complex biological matrix. Therefore, the ratiometric fluorescent probe can be proposed as a simple and effective tool for the detection and visualization of dual proteins.
研究领域:
分析化学
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生物化学
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荧光光谱
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MICROCHIMICA ACTA
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2019
·Vol. 186
·期 4
·1-7
·
IF 5.479
Li Zheng,Mao Guobin,Du Mingyuan,Tian Songbai,Niu Longqing,Ji Xinghu,He Zhike
A fluorometric method is described for the determination of the tumor biomarker mucin 1 (MUC1). It is based on signal amplification of the hybridization chain reaction (HCR), and the interaction between a luminescent ruthenium(II) complex and CdZnTeS quantum dots (QDs). If MUC1 bind to the biotin-labeled aptamer, it will initiate HCR with hairpins H 1 and H 2 to form a long-range dsDNA. The long nucleic acid chains are then linked on the surface of streptavidin-modified magnetic microparticles (MMPs) through streptavidin-biotin interaction. The luminescent ruthenium(II) complex is then embedded in the long dsDNA linked to the MMPs. Hence, there is little Ru complex in the supernatant after magnetic separation, and the fluorescence of the CdZnTeS QDs (best measured at excitation/emission wavelengths of 350/530 nm) is only slightly quenched. In the absence of target, the fluorescence of the CdZnTeS QDs is strongly quenched. Fluorescence increases linearly in the 0.2–100 ng·mL −1 MUC1 concentration range, and the LOD is 0.13 ng·mL −1 (at S/ N = 3). The method was applied to the determination of MUC1 in spiked human serum samples.
A fluorometric turn-on aptasensor for mucin 1 is described that is based on the interaction between a Ru(II) complex and quantum dots (QDs). The detection system includes biotin-labeled aptamer-H 0 , hairpins H 1 and H 2 , streptavidin-modified magnetic microparticles (MMPs), Ru(bpy) 2 (dppx) 2+ and CdZnTeS QDs.
研究领域:
分析化学
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生物传感器
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癌症诊断
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纳米技术
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PubMed
高影响因子
ANALYST
·
2020
·Vol. 146
·期 3
·949-955
·
IF 3.978
Fan Lu,Yeling Yang,Yucheng Liu,Fubing Wang,Xinghu Ji,Zhike He
High concentration of uric acid is usually related to cardiovascular and cerebrovascular diseases. Developing a simple method for the rapid and efficient detection of uric acid has a great significance in clinical diagnosis. In this work, alginate hydrogel microspheres embedded with CdZnTeS QDs and urate oxidase (Alg@QDs-UOx MSs) were prepared for the first time, and further used for point-of-care testing (POCT) of patients with a high concentration of uric acid. This strategy is mainly based on visual detection of H2O2, the product of uric acid after an enzymatic reaction. The proposed sensor (Alg@QDs-UOx MSs) has several advantages. First, it can reduce the interference of the proteins to the fluorescence of QDs. Second, Alg@QDs-UOx MSs help improve the stability of the CdZnTeS QDs as well as the activity of urate oxidase during storage. Third, it is easy to use, has fast response speed, and is of low cost. Therefore, the proposed sensor shows good application prospects. Simply through the built-in camera of a smartphone, we can visualize the urine samples from patients with a high concentration of uric acid within 10 minutes, and the accuracy rates were 100%. In the range of 100.0 μM to 900.0 μM, the I/I0 values and uric acid concentrations are in a great linear relationship (R2 = 0.9973), indicating that this method can be employed for quantitative analysis of uric acid in human urine (<10 mM). The limit of detection (LOD) is 20.3 μM.
研究领域:
医学诊断
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生物传感器
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材料科学
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化学工程
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PubMed
高影响因子