MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 12
·1-8
·
IF 5.479
Zhuo Shujuan,Fang Jing,Li Meng,Wang Jing,Zhu Changqing,Du Jinyan
A colorimetric assay is presented for the determination of ascorbic acid (AA). Manganese(II) doped carbon dots (Mn-CDs) were prepared by a convenient hydrothermal route and are shown to possess oxidase-like catalytic ability. They catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) by dissolved oxygen to form a blue colored product (oxTMB). AA can reduce blue oxTMB to colorless TMB. The fading of the blue color (measured at 652 nm) can be applied for quantifying AA in the 50 to 2500 nM concentration range and with a 9 nM detection limit. The method was successfully used for the quantitation of AA in real samples.
Schematic representation of a colorimetric assay platform for the sensitive detection of ascorbic acid (AA) in view of inhibitory effect of AA on the 3,3′,5,5′-tetramethylbenzidine (TMB) oxidation, benefitting from excellent oxidase-like catalytic activity of manganese(II) doped carbon dots (Mn-CDs).
研究领域:
分析化学
·
生物医学
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DOI
高影响因子
MICROCHIMICA ACTA
·
2020
·Vol. 187
·期 2
·1-7
·
IF 6.232
Wang Jiawei,Ni Pengjuan,Chen Chuanxia,Jiang Yuanyuan,Zhang Chenghui,Wang Bo,Cao Bingqiang,Lu Yizhong
Core-shell palladium cube@CeO 2 (Pd cube@CeO 2 ) nanoparticles are shown to display oxidase-like activity. This is exploited in a method for determination of the activity of alkaline phosphatase (ALP). The Pd cube@CeO 2 nanoparticles were thermally synthesized from Ce(NO 3 ) 3 , L-arginine and preformed Pd cube seeds in water. The Pd cube@CeO 2 nanoparticles catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) by oxygen. This results in the formation of oxidized TMB (oxTMB) with an absorption peak at 652 nm. Ascorbic acid (AA) is generated from the hydrolysis of L-ascorbic acid 2-phosphate (AAP) catalyzed by ALP. It can reduce oxTMB to TMB, and this results in a decrease of the absorbance. The method allows for quantitative determination of the activity of ALP in the range from 0.1 to 4.0 U·L −1 and with a detection limit down to 0.07 U·L −1 . Endowed with high sensitivity and selectivity, the assay can quantify ALP activity in biological system with satisfactory results.
Schematic illustration of Pd cube@CeO 2 core-shell nanoparticles for colorimetric determination of alkaline phosphatase.
研究领域:
生物化学
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纳米医学
·
分析化学
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DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
·
2022
·
IF 6.911
Yifei Li,Jingwen Li,Ya Cao,Ping Jiang,Yuguo Tang,Zutao Chen,Kun Han
Sensitive and specific assay of hepatitis C virus (HCV) RNA has a great clinical significance for the diagnosis of hepatitis C in window period. A colorimetric assay is described for determination of the RNA of hepatitis C virus. The method is based on the in situ synthesis of graphene quantum dot-silver nano-composites (GQD/Ag NCs), magnetic separation and catalyzed hairpin assembly reaction (CHA). The silver component of GQD/Ag NCs react with H 2 O 2 generated by glucose oxidase , which are induced via CHA. Then the light-yellow solution turns into colorless transparent in the presence of the target RNAs. The method has a linear response in the 25–500 pM RNA concentration range, and the detection limit is 24.84 pM. The method is simple, stable and sensitive and might be extend to the assay of other RNA viruses . The retro-transcription free and visual distinguishable properties endow this strategy a promising application in the screening of HCV.
研究领域:
医学诊断
·
分子生物学
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DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 130
·107670-107679
·
IF 3.84
Shoulian Wei,Jianwen Li,Yong Liu
Magnetic mesoporous nanoparticles of Fe3O4@mSiO2 were prepared through co-precipitation and tetraethoxysilane hydrolysis at 60 °C and pH 10 with hexadecyl trimethyl ammonium bromide as the template. Hydroxypropyl β-cyclodextrin was modified onto Fe3O4@mSiO2 under sodium citrate and N2 protection via an ultrasound process to increase the catalytic efficiency. The prepared nanoparticles were characterized by Fourier transform infrared spectrometry, X-ray diffraction, scanning electron microscopy and a peroxidase-like activity assay. The results showed that the prepared nanoparticles have magnetic properties, peroxidase-like activity and a loose spherical cluster structure. Compared with Fe3O4@mSiO2 nanoparticles, Fe3O4@mSiO2@HP-β-CD nanoparticles exhibit higher catalytic ability toward both H2O2 and 3,3′,5,5′-tetramethylbenzidine. Fe3O4@mSiO2@HP-β-CD nanoparticles can catalyse β-estradiol (β-E2) oxidation in the presence of H2O2 and be used as a colourimetric sensor for indirect detection of β-E2. A good linear relationship was obtained from 0.8 μM to 16 μM. The limit of detection of the proposed method was 0.2 μM. The visual method was successfully used in the analysis of β-E2 in commercial tablets and animal feeds, with recovery ranging from 92.6% to 110%.
研究领域:
生物化学
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分析化学
·
材料科学
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DOI
高影响因子
MICROCHIMICA ACTA
·
2022
·Vol. 189
·期 12
·1-9
·
IF 6.408
Zhang Xiaoni,Peng Jun,Xi Liping,Lu Ziwei,Yu Lili,Liu Meiru,Huo Dezhi,He Hua
An elaborate composite of molecularly imprinted polymer (MIP)-modified gold nanoparticles (AuNPs)@silica dioxide (SiO 2 ) was designed and prepared for real-time colorimetric determination of glutathione (GSH) in serum. Firstly, the MIPs were synthesized on the surface of SiO 2 utilizing GSH as template molecules. Then, AuNPs were synthesized on the surface of MIPs@SiO 2 to produce a composite of MIPs modified by AuNPs@SiO 2 . Compared with plain AuNPs, the composite possessed better peroxidase catalysis activity due to stabilization and protection from hydrophilic SiO 2 , which can catalyze H 2 O 2 to·OH oxidizing 3,3,5,5-tetramethylbenzidine (TMB) to the colored product. In addition, its selectivity was enhanced by MIP modification with special recognition cavities. With the composite as the sensor, GSH was precisely and sensitively detected in the range 5 ~ 40 μM with a limit of determination of 1.16 μM according to the principle of inhibitive peroxidase catalysis activity by GSH. The proposed colorimetric detection was successfully utilized for selective, convenient, and rapid determination of GSH in serum. It provided a new strategy for drug real-time monitoring and has high potential in clinical drug analysis. Graphical Abstract
研究领域:
纳米技术
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分析化学
·
生物传感器
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DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2020
·Vol. 187
·期 2
·1-9
·
IF 6.232
Sun Huiyuan,Liu Xueliang,Wang Xinhuan,Han Qiusen,Qi Cui,Li Yanmei,Wang Chen,Chen Yongxiang,Yang Rong
The authors describe a peroxidase-mimicking nanozyme composed of IrO 2 and graphene oxide (GO). It was synthesized from monodisperse IrO 2 nanoparticles with an average diameter of 1.7 ± 0.3 nm that were prepared by pulsed laser ablation in ethanol. The nanoparticles were then placed on polyallylamine-modified GO nanosheets through electrostatic interaction. The peroxidase-like activity of the resulting nanocomposites was evaluated by catalytic oxidation of 3,3′,5,5′-tetramethylbenzidine in the presence of H 2 O 2 . Kinetic results demonstrated that the catalytic behavior of the nanocomposites follows Michaelis-Menten kinetics. Experiments performed with terephthalic acid and cytochrome C confirmed that the peroxidase-like activity originated from the electron transfer mechanism rather than from generation of hydroxy radicals. The peroxidase-like activity is inhibited in the presence of ascorbic acid (AA). Based on this property, a colorimetric assay was developed for the determination of AA by exploiting the peroxidase-like activity of IrO 2 /GO nanocomposites. The linear relationship between absorbance at 652 nm and the concentration of AA was acquired. The limit of detection for AA is 324 nM. Further applications of the method for AA detection in real samples were also successfully demonstrated.
Schematic of the preparation of polyallylamine (PAH)-stabilized IrO 2 /GO nanocomposites and the colorimetric detection of AA based on the peroxidase-like activity of IrO 2 /GO nanocomposites.
研究领域:
分析化学
·
纳米技术
·
生物化学
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DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Daxiang Dai,Hongying Liu,Huan Ma,Zhiheng Huang,Chunchuan Gu,Mingzhen Zhang
In this paper, gold nanoparticles-doped Cu 2 O cubes (Cu 2 O Au nanocomposites) with peroxide-like character were readily prepared through a simple two-step method and were used for sensitive readout of H 2 O 2 with color variation for the first time. By changing reaction temperature and feed rate, Cu 2 O nanocrystals with very small size were obtained and were then used to prepare Cu 2 O Au nanocomposites. HR-TEM, SEM, and XRD were used to characterize their morphology and size. The results revealed that the as-prepared Cu 2 O Au nanocomposites displayed rough cube morphology, with Cu 2 O cube, ca. 85 nm in size, filled with 8 nm spheres. In the presence of H 2 O 2 , 3,3,5′,5′-tetramethyl benzidine (TMB) was catalyzed by Cu 2 O Au nanocomposites and generated color changes, which was employed to detect H 2 O 2 . By comparison with Cu 2 O nanocrystals with different sizes, Cu 2 O Au nanocomposites exhibited highest peroxide-like activity, which relies heavily on the pH and temperature in the reaction systems and satisfies with the Michaelis-Menten kinetics. Based on these findings, a colorimetric method was developed to detect H 2 O 2 over a range between 0.4 μM and 1000 μM. This platform extends a great prospect in the field of clinical diagnosis, food safety, and environmental monitoring.
研究领域:
材料科学
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分析化学
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纳米技术
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生物化学
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产品关联
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2021
·
IF 6.986
Stanislas Nsanzamahoro,Wei-Feng Wang,Ying Zhang,Cheng-Bo Wang,Yan-Ping Shi,Jun-Li Yang
Designing analytical approaches for enzymatic activity monitoring with high sensitivity and selectivity is of critical value for the diagnosis of diseases and biomedical studies. In this study, we have created a facile one-step synthetic route to prepare orange-red color and yellow fluorescent silicon-containing nanoparticles (Si CNPs) by mixing 3(2-aminoethylamino) propyl (dimethoxymethylsilane) and hydroquinone (HQ) in an aqueous solution. Inspired by the HQ-regulated facile synthetic step and the generation of HQ from α-glucosidase (α-Glu)-catalyzed hydrolysis of 4-hydroxyphenyl-α-d-glucopyranosyl (4-HPαDG), we have designed a straightforward colorimetric and fluorometric α-Glu activity assay using a commercially available 4-HPαDG as the α-Glu substrate. Fluorescent and colorimetric assays for α-Glu activity measurement have been thereby established and exhibited detection limits as low as 0.0032 and 0.0046 U/mL, respectively. Under single excitation at 370 nm, the prepared Si CNPs emitted yellow fluorescence at 520 nm and exhibited an absorbance peak at 390 nm. In addition, the proposed approach reveals various advantages including easy operation, time-saving, and good anti-interference ability. Hence, it could improve the progress of fluorometric and colorimetric enzymatic activity assays with high sensitivity and simplicity. Moreover, the proposed approach was applied for α-Glu inhibitor screening, and its feasibility in real samples was measured by detecting the α-Glu activity in human serum samples.
研究领域:
分析化学
·
生物医学
·
酶学
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DOI
PubMed
高影响因子
RSC Advances
·
2023
·Vol. 13
·期 39
·27283-27291
·
IF 3.9
Ying Shen,Hongyuan Wu,Xia Luo,Haizhi Zhang,Liming Cheng
In addition to size, shape and morphology, enzyme–mimetic property could be efficiently regulated by controlling composition, forming complexes or hybrids, and surface modification. Herein, Pd nanoparticles with an average diameter of 2.52 nm were decorated on ultrathin 2D copper(II)-porphyrin derived metal–organic framework (MOF) nanosheets by a simple reduction method for catalytic activity regulation. In comparison with other nanozymes, the as-synthesized Pd modified 2D MOF hybrid nanosheets (Pd@Cu-TCPP(Fe)) presented excellent peroxidase–mimic activity, exhibiting an even superior catalytic ability towards H2O2 with a Michaelis–Menten constant as low as 2.33 mM. Based on a cascade reaction between glucose oxidase and Pd@Cu-TCPP(Fe), a colorimetric method for the detection of glucose was established and validated with a wide linear range (0.2–8.0 mM), good recovery (89.5–94.2%) and nice reproducibility (3.65%). All these features guaranteed its excellent ability for glucose determination in human cerebrospinal fluids. This study could offer a valuable reference for constructing novel optical biosensors.
研究领域:
纳米材料
·
催化
·
生物传感器
·
分析化学
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产品关联
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2021
·Vol. 188
·期 5
·1-10
·
IF 5.833
Liu Hui,Huang Pengcheng,Wu Fang-Ying,Ma Lihua
A colorimetric assay for acid phosphatase (ACP) was constructed that is based on in situ polymerization of aniline catalyzed by gold nanoparticles (AuNPs). Aniline can be polymerized by ammonium persulfate (APS) in acidic condition and form gold-polyaniline core-shell nanoparticles (Au@PANI NPs) in the presence of AuNPs with the assistance of sodium dodecyl sulfate (SDS). AuNPs were also found to accelerate the polymerization process of aniline and thus shorten the reaction time. Upon the introduction of ascorbic acid (AA), the oxidant APS was consumed via the redox reaction. That led to the suppression of the formation of PANI. Consequently, ACP activity can be supervised on the basis of hydrolysis of 2-phospho-L-ascorbic acid trisodium salt (AAP) catalyzed by ACP to release AA. With the increase of ACP activity, the intensity ratio of the absorbance at λ 705 nm (A 705 ) and the absorbance at λ 530 nm (A 530 ) gradually decreased and the color gradually changed from dark-green to light-green to blue-gray to purple and eventually to pink. This method for ACP determination worked in the range 0.40 to 2.00 U·L −1 . The detection limit is 0.043 U·L −1 . The assay was applied to determine ACP in human serum. The recovery ranged from 81.0 to 104.6%. Relative standard deviation was less than 5%. This suits the request for biological sample analysis.
Schematic presentation of the colorimetric determination of acid phosphatase activity and inhibitor screening based on in situ polymerization of aniline catalyzed by gold nanoparticles. : acid phosphatase (ACP); : gold nanoparticles (AuNPs); : gold-polyaniline core-shell nanoparticles (Au@PANI NPs); ascorbic acid (AA); 2-phospho-L-ascorbic acid trisodium salt (AAP).
研究领域:
生物化学
·
分析化学
·
生物医学工程
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DOI
PubMed
高影响因子
ANALYTICAL LETTERS
·
2023
·
IF 2
Wengan Zhang,Binjie Chen,Ruke Wang,Jing Liu,Bo Wang
Simple, low-cost, and fast determination of cysteine and glutathione with high sensitivity is an essential problem to evaluate the physiological processes in living organisms. Artificial nanozymes have provided considerable opportunities in biosensing. In this work, using a graphene-based ternary nanozyme, we present a simple but efficient colorimetric method for the determination of cysteine and glutathione. The nanozyme exhibits excellent and stable catalytic performance toward H2O2 and catalyzes the 3,3′,5,5′-tetramethylbenzidine chromogenic reaction. However, this reaction is significantly suppressed by cysteine and glutathione. Thus, a sensitive colorimetric method is presented based upon this inhibition. Excellent performance with low detection limits, good selectivity, and rapid analysis suggests potential bioanalytical applications for the determination of cysteine and glutathione.
研究领域:
分析化学
·
生物传感器
·
纳米技术
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产品关联
DOI
高影响因子
STARCH-STARKE
·
2020
·
IF 2.226
Xue-Li Liu,Kun Zhang,Yu Hu,Zhengjuan Zhang,Jun Chen,TianLin Ma,JiaJia Wang
A new class of hydroxypropyl starch, γ-hydroxypropyl starch (γ-HPS), is synthesized by using 3-chloropropanol as the etherifying reagent. Two independent procedures for the determination of the number of moles of alkylene oxide combined per anhydroglucose unit (molar substitution, MS) in γ-HPS are described. The feasibility of the Zeisel-gas chromatographic technique and colorimetric determination are testified, and especially in the second approach, the stability and accuracy of dehydration process are also investigated. The concentrated sulfuric acid dehydration oxidation is replaced with 2-iodoxybenzoic acid oxidation while retaining the same acid degradation and the same ninhydrin color reaction. Furthermore, the reliability and the range of application of the methods are tested by analyzing three samples of γ-HPS and unmodified starch derivatives, and the results indicate that values of MS are in good agreement with each testing method.
研究领域:
食品科学
·
分析化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）