ANALYST
·
2012
·Vol. 137
·期 19
·4552-4558
·
IF 4.23
Xing Liu,Qi Wang,Huihui Zhao,Lichun Zhang,Yingying Su,Yi Lv
Inorganic nanomaterials that mimic enzymes are fascinating as they potentially have improved properties relative to native enzymes, such as greater resistance to extremes of pH and temperature and lower sensitivity to proteases. Although many artificial enzymes have been investigated, searching for highly-efficient and stable catalysts is still of great interest. In this paper, we first demonstrated that bovine serum albumin (BSA)-stabilized MnO2 nanoparticles (NPs) exhibited highly peroxidase-, oxidase-, and catalase-like activities. The activities of the BSA-MnO2 NPs were evaluated using the typical horseradish peroxidase (HRP) substrates o-phenylenediamine (OPD) and 3,3′,5,5′-tetramethylbenzidine (TMB) in the presence of either hydrogen peroxide or dissolved oxygen. These small-sized BSA-MnO2 NPs with good dispersion, solubility and biocompatibility exhibited typical Michaelis–Menten kinetics and high affinity for H2O2, OPD and TMB, indicating that BSA-MnO2 NPs can be used as satisfactory enzyme mimics. Based on these findings, BSA-MnO2 NPs were used as colorimetric immunoassay tags for the detection of goat anti-human IgG in place of HRP. The colorimetric immunoassay using BSA-MnO2 NPs has the advantages of being fast, robust, inexpensive, easily prepared and with no HRP and H2O2 being needed. These water-soluble BSA-MnO2 NPs may have promising potential applications in biotechnology, bioassays, and biomedicine.
研究领域:
材料科学
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生物化学
·
生物技术
·
纳米技术
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产品关联
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
·
2024
·
IF 4.9
Miaomiao Song,Weihua Ma
Increasing attention has been directed towards oxidase mimics due to their catalytic ability toward enzyme substrates in the absence of H 2 O 2 , offering great colorimetric sensing potential in assays and diagnostics. However, slow electron-transfer and unstable absorbance over time often lead to unsatisfactory enzymatic reaction rates and unreliable readouts, significantly reducing detection efficiency and accuracy. Herein, we report on an Ag 6 Si 2 O 7 nanozyme utilizing 3,3′,5,5′-tetramethylbenzidine (TMB) as a chromogenic substrate, demonstrating excellent oxidase-like activity and long-term stable colorimetric signals. Experimental results reveal that the excellent catalytic kinetics of Ag 6 Si 2 O 7 (K m = 0.197 mM, Vmax = 5.1 × 10 −7 M/s) are attributed to ultrafast electron transfer between Ag + and TMB, mediated by Ag 2 O intermediates formed from self-released alkaline ions. Additionally, self-released H 2 SiO 4 2− improves the stability of the oxidized substrate, resulting in a long-term stable colorimetric signal (∼20 min), which exhibits reliable accuracy regardless of the time point at which analyte is added within 20 min, thus eliminating the interference of individual operation time errors. Ascorbic acid (AA) is selected as the target molecule to assess the performance of the Ag 6 Si 2 O 7 -TMB colorimetric sensing system. This approach demonstrates a wide detection range from 5 to 300 μM and a detection limit of 0.452 μM. The developed colorimetric sensing strategy exhibits good stability, specificity, rapidity, and potential application in real sample detection.
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
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 71
·66963-66970
·
IF 3.289
Haiguan Yang,Junqi Zha,Peng Zhang,Yuhao Xiong,Linjing Su,Fanggui Ye
CoS, which was prepared using a facile solvothermal method, and characterized using various analytical techniques, was demonstrated for the first time to exhibit intrinsic peroxidase-like activity. CoS catalyzed the oxidation of the peroxidase substrate 3,3′,5,5′-tetramethylbenzidine in the presence of H2O2 rendering the reaction solution blue, which is the principle used for H2O2 sensing. The mechanism of the CoS catalysis was also investigated. Under optimal conditions, the linearity of H2O2 detection ranged from 0.05 to 0.8 mM (R2 = 0.9965). More importantly, using the reducibility of glutathione and the strong affinity to thiol compounds exhibited by mercury ions (Hg2+), a novel “off–on” colorimetric sensor for Hg2+ determination was designed using CoS as a peroxidase mimics. The analytical platform for Hg2+ determination was developed, ranging from 0.25 to 3 μM (R2 = 0.9965). The limit of detection was 0.1 μM. CoS exhibited several advantageous features including good chemical stability, ease of preparation, simple purification, and excellent reproducibility.
研究领域:
生物化学
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分析化学
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材料科学
✓ 已验证
DOI
高影响因子
Analytical Methods
·
2014
·Vol. 7
·期 4
·1300-1306
·
IF 1.938
Yuhao Xiong,Siheng Chen,Fanggui Ye,Linjing Su,Cong Zhang,Shufen Shen,Shulin Zhao
In this paper, magnetic core–shell nanoflowers Fe3O4@MnO2 were fabricated via a solvothermal method. We demonstrated that the as-synthesized magnetic nanoflowers Fe3O4@MnO2 possess intrinsic oxidase-like activity in a wide pH range and can catalytically oxidize 4-aminoantipyrine (4-AAP) and phenol substrates to form pink color products without the requirement for additional oxidizing agents. On the basis of this phenomenon, a simple colorimetric method for the determination of phenol was developed. A wide linear detection range can be obtained from 1.0 μM to 120 μM (R2 = 0.9962) with a detection limit of 0.15 μM. And the method was applied to determine phenol in wastewater with good recoveries ranging from 96.0 to 101.5%. Furthermore, benefitting from chemical stability and easy recovery (by simple magnetic separation) of Fe3O4@MnO2, the oxidase mimetics have excellent reusability and reproducibility in cycle analysis.
研究领域:
材料科学
·
分析化学
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2024
·Vol. 48
·期 37
·16323-16330
·
IF 2.7
Xiaoyue Yue,Chaoyun Wu,Chenxu Hao,Yanhong Bai
The abuse of tetracycline (TC) has led to serious threats to human health and the environment. Therefore, the rapid and sensitive detection of tetracycline is of particular importance. Herein, we successfully synthesised a bimetallic nanozyme D-Fe/Co-MOF with oxidase activity and established a colourimetric sensor. The complex of Fe2+ in D-Fe/Co-MOF and TC can release hydroxyl radicals (˙OH) and promote the oxidation of TMB. As a result, the colour of the detection system significantly changes, enabling the sensitive colourimetric detection of TC. Compared with the existing Fe/Co-MOF sensor, D-Fe/Co-MOF can effectively reduce the detection error caused by hydrogen peroxide decomposition, improving the accuracy of TC detection. Under the optimal conditions, the absorbance at 652 nm showed a good linear relationship with TC concentration in the range of 0.35–220 μg mL−1. The detection limit was as low as 0.0719 μg mL−1, considerably lower than the national safety standard. The proposed colourimetric sensor was also successfully used for the detection of TC in actual milk samples, and the results were in good agreement with those obtained via liquid chromatography. The proposed strategy for the detection of TC in food is expected to contribute to ensuring food safety and human health.
研究领域:
生物化学
·
环境科学
·
食品安全
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产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2024
·Vol. 191
·期 5
·1-11
·
IF 5.3
Liu Qingju,Zhu Junyi,Wang Hui,Luan Yunxia,Zhang Zhikun
A covalent organic framework–based strategy was designed for label-free colorimetric detection of pesticides. Covalent organic framework–based nanoenzyme with excellent oxidase-like catalytic activity was synthesized. Unlike other artificial enzymes, porphyrin-based covalent organic framework (p-COF) as the oxidase mimic showed highly catalytic chromogenic activity and good affinity toward TMB without the presence of H 2 O 2 , which can be used as substitute for peroxidase mimics and H 2 O 2 system in the colorimetric reaction. Based on the fact that the pesticide-aptamer complex can inhibit the oxidase activity of p-COF and reduced the absorbance at 650 nm in UV–Vis spectrum, a label-free and facile colorimetric detection of pesticides was designed and fabricated. Under the optimized conditions, the COF-based colorimetric probe for pesticide detection displayed high sensitivity and selectivity. Taking fipronil for example the limit of detection was 2.7 ng/mL and the linear range was 5 –500,000 ng/mL. The strategy was successfully applied to the detection of pesticides with good recovery , which was in accordance with that of HPLC–MS/MS. The COF-based colorimetric detection was free of complicated modification H 2 O 2 , which guaranteed the accuracy and reliability of measurements. The COF-based sensing strategy is a potential candidate for the sensitive detection of pesticides of interests. Graphical Abstract
研究领域:
分析化学
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生物医学工程
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2023
·
IF 4.4
Huan Jiang,Yucui Zhang,Ruyi Tang,Xia Zhang,Xuemin Xia,Baihui Wang,Lei Han
Enzyme mimetics have been widely applied on H 2 O 2 assay, but it is still challenging and interesting to realize the sensitive detection for ultra-trace H 2 O 2 . Here, an ultrasensitive Raman assay method based on novel WO 3 @IP6-Fe 3+ enzyme mimetics with peroxidase-like activity was established. WO 3 microspheres (MSs) were found to have weak peroxidase-like activity, and the combination of IP6-Fe 3+ and WO 3 can produce stronger activity. WO 3 @IP6-Fe 3+ MSs showed polyhedron-like structure, uniform size, and smooth surface. Although WO 3 @IP6-Fe 3+ enzyme mimetics have low catalytic efficiency and high absorbance background, the proposed Raman method can bypass the above problems. In Raman method, high concentration of WO 3 @IP6-Fe 3+ can be used to overcome low catalytic efficiency without high absorbance background. Moreover, 3,3′,5,5′-tetramethylbenzidine oxide has prominent characteristic Raman peak at 1608 cm −1 , greatly improving the sensitivity and eliminating interference of impurities. Due to the high sensitivity and low background, Raman assay showed the ultra-low limit of detection (5.49 × 10 −15 M), which was 4–7 orders of magnitude lower than other detection methods. The ultrasensitive Raman assay not only provided the possibility for the enzyme mimetics-based detection of ultra-trace H 2 O 2 , but also enable the enzyme mimetics with low activity to be applied.
研究领域:
生物化学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
·
2024
·
IF 4.9
Xu Liu,Peide An,Yide Han,Hao Meng,Xia Zhang
Cu-based nanozyme shows good oxidase-like activities due to the changeable states of Cu(II) and Cu(I), which are proven to be effective in the electron transfer in the redox process. Herein, the self-made MOF-818 with more Cu(II) loading was synthesized through a modified two-steps hydrothermal routes, which was then used as a sacrificial precursor to construct copper/zirconium composite oxides nanozymes (CN-MOF-818). The pyrolysis temperature was varied to obtain the best enzyme-like activities of the resulting CN-MOF-818. The laccase-like and catecholase-like activities were evaluated by using the oxidation of the mixture of 4-aminoantipyrine (4-AAP) and 2,4-dichlorophenol (2,4-DP), and 3,5-Di- tert -butylcatechol (3,5-DTBC) respectively. The enzyme-like activities were optimized through altering the catalytic conditions, and the corresponding enzyme catalytic kinetics including K m and V max were also determined. The enzyme-like mechanism of the CN-MOF-818 were also discussed based on EPR technique and the in-situ FT-IR analyses. In comparison with the pristine MOF-818 and the other reported Cu-based mimics, the as-prepared CN-MOF-818 exhibits the higher oxidase mimetic activities. These CN-MOF-818 can also be employed to detect the epinephrine with a low detection limit of 1.63 μM.
研究领域:
纳米技术
·
催化
·
分析化学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2018
·
IF 8.173
Liang Tian,Jinxu Qi,Olayinka Oderinde,Chen Yao,Wei Song,Yihong Wang
Enzyme mimics have been developed for bioassay of nucleic acids , with some of them involving complicated labeling. Herein, we report a label-free bioassay for ultrasensitive electronic determination of microRNA at an ultralow concentration based on target-triggered long-range self-assembly DNA-based hybridization chain reaction (HCR) protocol coupled with bienzyme mimics synergistic catalysis strategy. In this work, a planar intercalation molecule, copper (II) complex, is applied for the first time as a small molecule enzyme mimic as well as intercalation molecule in microRNA biosensor for signal amplification . Fe 3 O 4 nanozyme were used as a separate and enriched target under magnetic field, and also in combination with HCR protocol detected in 3,3’,5,5’-tetramethylbenzidine+hydrogen peroxide (TMB+H 2 O 2 ) system to improve the sensitivity of the biosensor. Under optimal conditions, these strategies present good electrochemical behaviors for the detection of microRNA with a wide range from 100 aM to 100 nM and at relatively low detection limit of 33 aM This remarkable sensitivity can make this proposed approach a promising scheme for development of next-generation microRNA sensors without the need of enzyme labeling or fluorophore labeling.
研究领域:
生物化学
·
分子生物学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Ya Xu,Jihong Zhou,Peng Sun,Ping Li,Dongxue Han,Xiaohong Wang,Fang Chai
Artificial mimic enzymes have attracted wide attention for their superior characteristics to natural enzymes in extensive applications of diagnosis and therapy. In this paper, a nanozyme Cu-BDC@FeMo 6 was designed and fabricated by embedding polyoxometalate (NH 4 ) 3 [FeMo 6 O 18 (OH) 6 ]·6H 2 O (FeMo 6 ) into a copper-based metal–organic framework (Cu-BDC). The integration of FeMo 6 and Cu MOF based on the synergies of oxidability of FeMo 6 and oxygen-driven reversible Cu + /Cu 2+ enhanced the peroxidase mimicking activity, which accomplished the sensitive visual monitoring of H 2 O 2 and dopamine (DA). The detection of H 2 O 2 was driven by Cu-BDC@FeMo 6 catalyzing the oxidation of TMB with colorimetric evolution to blue, and consecutive monitoring DA via the reverse process of reduction of ox-TMB was further achieved. The limit of detection (LOD) of H 2 O 2 and DA were 10 μM and 2.27 μM, with excellent stability, and outstanding selectivity. The mechanism of the catalysis was further evaluated, and the generation of O 2 · - played a crucial role in the catalysis for oxidation. The logic gate design was constructed to illustrate the process and application. This work provides a feasible reference for the reasonable design of simulated enzyme in biosensor applications.
研究领域:
生物传感
·
材料科学
·
仿生催化
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2021
·
IF 13.084
Yutong Wang,Lijun Yang,Mengfan Wang,Jiaxing Zhang,Wei Qi,Rongxin Su,Zhimin He
Enzymes play vital roles in catalyzing biochemical reactions with high activity and selectivity, which is largely attributed to the delicately organized structure and groups at catalytic domains. Reconstruction of the enzymatic catalytic domains in artificial systems, to produce enzyme-like mimic, has become an attractive but challenging subject. Herein, inspired by the helical structure in the catalytic center of natural phosphatases, we created a phosphatase-like mimic through the self-assembly of de novo designed helical heptapeptides. The helical heptapeptides were elaborately decorated with well-studied catalytic groups and exhibited obvious phosphatase-like catalytic activity upon hierarchically self-assembling. In comparison with β-sheet-organized peptide assemblies, we emphasized the significance of helical structure in the hydrolysis of phosphoester bonds (over 1000 times higher in catalytic efficiency). The structure–activity relationship reveals that the phosphatase-like function attributed to the specific helical dipole moment for the binding of substrates as well as the supramolecular assembly for the formation of catalytic center. Moreover, we verified the feasibility of these helical species as a potential substitute for adenosine triphosphatase (ATPase) and alkaline phosphatase (ALPase) in some specific biological processes. This work not only presents an approach for the construction of artificial enzymes with simple peptide modules but also provides a model for primitive enzymes formed from helical short peptides that relied on self-assembly to achieve a folded structure.
研究领域:
生物化学
·
分子生物学
·
合成生物学
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产品关联
DOI
高影响因子
Analytical Methods
·
2019
·Vol. 11
·期 42
·5472-5477
·
IF 2.378
Linjie Wang,Kun Ye,Jianming Pan,Hongwei Song,Xin Li,Xiangheng Niu
As a typical biomarker for disease diagnosis in clinical practice, alkaline phosphatase (ALP) plays a critical role in regulating the dephosphorylation process of biomolecules. On this account, exploration of an effective and simple means of ALP activity measurement becomes very significant. In this work, we report a catalytic reaction-based colorimetric method for the monitoring of ALP activity via employing nanostructured MnO2 as a favorable oxidase mimic. The prepared MnO2 microspheres exhibit good oxidase-like capacity to induce the catalytic oxidation of colorless 3,3′,5,5′-tetramethylbenzidine (TMB) to deep-blue TMBox; when ALP hydrolyzes ascorbic acid phosphate, the produced ascorbic acid (AA) with a certain reducing power can destroy the MnO2 enzyme mimic by reducing it to Mn2+, dramatically suppressing the TMB chromogenic reaction. Based on the strategy, a convenient and high-performance colorimetric method was established for ALP activity sensing, giving a wide linear range from 0.5 to 120 U L−1. With the help of N-ethylmaleimide as an efficient masking agent for biothiols, the colorimetric approach could provide excellent specificity for ALP activity detection. Reliable and precise measurement of the analyte in practical samples was also verified by our assay, indicating its promise as a feasible tool for clinical diagnosis.
研究领域:
生物化学
·
医学诊断
·
纳米材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）