ANALYTICAL AND BIOANALYTICAL CHEMISTRY
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2024
·
IF 3.8
Hui Yingfei,Wang Mingyue,Liu Yinsheng,Peng Liping,Tian Jiaying,Ren Borong,Guo Hao,Yang Wu
In this study, a ratiometric fluorescent sensor CdTe QDs@ZIF-8 with butterfly spectra is successfully constructed by in situ encapsulating mercaptopropionic acid-modified CdTe quantum dots in zeolitic imidazolate framework-8 (ZIF-8) with a simple strategy, and used for the detection of tetracycline in fluorescence/smartphone colorimetry dual-mode. ZIF-8 not only reduces the agglomeration of the quantum dots but also surprisingly generates a new green fluorescence signal at 524 nm while the red fluorescence of the CdTe quantum dots at 650 nm quenches when tetracycline is added. The two opposing fluorescence signals create a butterfly-shaped fluorescence spectrum, allowing the sensor to detect tetracycline over a linear range of 0–70 μM with the detection limit (LOD) of 0.0155 μM by using a ratiometric fluorescence technique. What is more, based on the obvious color change of the fluorescent sensor gradually from red to green under UV light, a highly stable point-of-care testing sensor has been developed for on-site detection of tetracycline through color recognition by smartphones, which can be used for real-time detection of this antibiotic in the range of 0–1000 μM with the LOD of 0.0249 μM. This work provides a simple and efficient method for the on-site detection of tetracycline. Graphical Abstract
研究领域:
分析化学
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纳米技术
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环境科学
·
食品科学
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产品关联
DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
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2012
·
IF 4.555
Liang Zhao,Yin Jin,Zhangwei Yan,Yuanyuan Liu,Hongjun Zhu
A simple, rapid, sensitive and field-portable colorimetric technique for the determination of Cr(III) in aqueous solution based on an aggregation-induced color transition of gold nanoparticles (AuNPs) has been developed. AuNPs were first functionalized with a dithiocarbamate-modified N -benzyl-4-(pyridin-4-ylmethyl)aniline ligand (BP-DTC). Chelation of Cr(III) by several of these ligands, bound to different nanoparticles, led to nanoparticle aggregation in solution. This gave rise to a color change from wine-red to blue that was discernible by the naked eye and an easily measurable alteration in the extinction spectrum of the particles. The method could be used to determine Cr(III) with a detection limit of 31 ppb. Furthermore, selective detection of trace Cr(III) in aqueous solution in the presence of 12 other transition metal ions has been achieved. Toward the goal of practical applications, the sensor has been further evaluated with a view to monitoring Cr(III) in nutritional supplements and the blood of diabetes patients and also applied in the indirect determination of Cr(VI) in waste water.
研究领域:
分析化学
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环境科学
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DOI
高影响因子
MICROCHIMICA ACTA
·
2024
·Vol. 191
·期 10
·1-12
·
IF 5.3
Xiao Rongsheng,Dai Hongliang,Liu Xingyu,Qi Jingwen,Bao Meishuo,Wang Xingang,Li Mingde,Zhang Wuxiang,Yan Dengxin
A novel colorimetric approach specifically designed to effectively identify the presence of 3-aminophenol (3-AP) in environmental water is introduced. Briefly, a nitrogen-doped carbon-supported cobalt nanozyme (Co@CN-1) was synthesized and utilized to improve the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of peroxymonosulfate (PMS). Comparative catalytic reactions confirmed that the performance of PMS as an activator exceeds that of hydrogen peroxide catalytically by a factor of 3.5. The catalytic reaction parameters underwent optimization, further resulting in the derivation of a linear detection equation for 3-AP, expressed as inhibition rate (IR%) = 3.35[3-AP]—4.36 (0–20 μM, R 2 = 0.994) and IR% = 1.43[3-AP] + 31.87 (20–36 μM, R 2 = 0.992), with the limit of detection (LOD) of 2.84 μM. The linear relationship between 3-AP concentration and the conversion of color to grayscale value (GSV) was established by smartphones, expressed as GSV = 1.28[3-AP] + 147.10 ( R 2 = 0.972). Density functional theory calculations revealed that Co acts as the preferred active site for donating electrons in PMS activation. This work provides a rapid and accurate approach for monitoring 3-AP concentration, enabling real-time analysis and potentially contributing to environmental and ecological studies. Graphical Abstract
研究领域:
环境科学
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分析化学
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产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2020
·
IF 7.1
Yong Liu,Ensheng Xu,Chao Xu,Wei Wei
As a tumor-related enzyme, PARP-1 activity is closely related to the occurrence of cancer. Sensitive detection of PARP-1 activity is of significance in the early diagnosis and treatment of cancer. Therefore, the gold nanorods (AuNRs) based biological nanoprobe was constructed for the visual and label-free detection of PARP-1 activity. dsDNA which activate PARP-1 was modified on AuNPs ( [email protected] ). MoO 4 2− is added to catalyze H 2 O 2 and KI to accelerate the etching of AuNRs. In the presence of PARP-1, hyperbranched poly (ADP-ribose) polymers (PAR) formed on the surface of [email protected] ( [email protected] @PAR). A large number of PO 4 3- of the PAR reacted with MoO 4 2− to generate PMo 12 O 40 3- . Thus, PO 4 3- diminished MoO 4 2− concentration in solution, preventing the etching of AuNRs. Therefore, PARP-1 prevented the etching of AuNRs. With the increasing concentration of PARP-1, the color of the solution changed from light blue to brown obviously. The method was applied to assay actual samples with satisfactory results. The strategy has the advantages of rapid quantitative analysis of PARP-1 activity with naked eyes, simple operation and good application prospect.
研究领域:
生物化学
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纳米医学
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肿瘤学
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产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
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2020
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IF 3.862
Ming Li,Guangsen Xiong,Yuling Zhang,Xiaoniu Yu,Qianyong Cao,Huining Xiao
Rhodamine chromophore was introduced into a chitosan based adsorbent developing for Hg (II) detection and removal in aqueous solution. The adsorbent displayed highly sensitive and selective fluorimetric and colorimetric response to Hg (II) with barely interference with more than ten kinds of competitive metal ions. The adsorbent exhibited strong orange fluorescence emission while encountering Hg (II) with the colour turning to red immediately and could be easily detected by naked eyes. In addition, the detection limit of the adsorbent was calculated to be 8.24 × 10 −7 M, and the adsorption capacity was as high as 139.08 mg/g according to the batch adsorption experiments. Furthermore, the interaction between adsorbent and Hg (II) was verified to fit well with Langmuir isotherm model and the pseudo-second-order kinetic model. Thermodynamic studies demonstrated that lower temperature was benefit for the adsorption.
研究领域:
环境科学
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分析化学
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产品关联
DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
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2021
·
IF 4.098
Jingyu Pang,Ruyan Xie,Sophie Chua,Yu Zou,Mingyu Tang,Fang Zhang,Fang Chai
A dual-mode colorimetric and fluorimetric probe was successfully established based on silver/copper bimetallic nanoparticles (AgCu-BNPs). The AgCu-BNPs were confirmed as individually bimetallic nanoparticles with a mean size of 7.7 ± 0.2 nm, as characterized by high resolution transmission electron microscopy. Intriguingly, the AgCu-BNPs possess both surface plasmon resonances (SPR) and fluorescence emission. AgCu-BNPs emanate bright blue fluorescence with optical emission centered at 442 nm with high quantum yield of 30.3%, and AgCu-BNPs were attenuated or even quenched by Hg 2+ via both static and dynamic quenching, coincidently accompanied by a visible color change, which endow AgCu-BNPs a unique utility as dual-mode colorimetric and fluorimetric probes. The detection limits as low as 89 nM and 9 nM were determined by dual-mode of AgCu-BNPs, respectively. The recovery rates in real samples were found to be 97.3–118.8%, and 89.5–112.7% by colorimetric and fluorescent methods separately, demonstrates the good environmental tolerance of the dual-mode probe.
研究领域:
分析化学
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环境科学
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纳米技术
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产品关联
DOI
PubMed
高影响因子
Analytical Methods
·
2012
·Vol. 4
·期 9
·2711-2714
·
IF 1.547
Yanli Zhou,Zhichong Yang,Maotian Xu
A simple, reliable and sensitive colorimetric method for the detection of lysine was developed based on the use of citrate-stabilized gold nanoparticles (AuNPs). In acid media (pH = 3.0), AuNPs exhibited a sensitive color change from red to blue after the addition of lysine for 30 min at room temperature, which could directly be seen with the naked eye and monitored by UV-vis absorption spectroscopy. Results showed that the absorbance ratio (A680/A520) was linear for a lysine concentration in the range of 1 to 70 μM (r = 0.995), and the limit of detection was 0.8 μM at a signal-to-noise ratio of 3. This method also demonstrated excellent selectivity for lysine over other amino acids. For the analysis of lysine in food samples, precision and accuracy were checked.
研究领域:
分析化学
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生物化学
✓ 已验证
DOI
高影响因子
SENSORS
·
2013
·Vol. 13
·期 1
·1064-1075
·
IF 1.953
Zhenzhu Zheng,Jing Han,Wensheng Pang,Juan Hu
With an internal transcribed spacer of 18 S, 5.8 S and 26 S nuclear ribosomal DNA (nrDNA ITS) as DNA marker, we report a colorimetric approach for authentication ofPseudostellaria heterophylla(PH) and its counterfeit species based on the differentiation of the nrDNA ITS sequence. The assay possesses an unlabelled G-quadruplex DNAzyme molecular beacon (MB) probe, employing complementary sequence as biorecognition element and 1:1:1:1 split G-quadruplex halves as reporter. In the absence of target DNA (T-DNA), the probe can shape intermolecular G-quadruplex structures capable of binding hemin to form G-quadruplex-hemin DNAzyme and catalyze the oxidation of ABTS2−to blue-green ABTS•−by H2O2. In the presence of T-DNA, T-DNA can hybridize with the complementary sequence to form a duplex structure, hindering the formation of the G-quadruplex structure and resulting in the loss of the catalytic activity. Consequently, a UV-Vis absorption signal decrease is observed in the ABTS2−-H2O2system. The “turn-off” assay allows the detection of T-DNA from 1.0 × 10−9to 3.0 × 10−7mol·L−1(R2= 0.9906), with a low detection limit of 3.1 × 10−10mol·L−1. The present study provides a sensitive and selective method and may serve as a foundation of utilizing the DNAzyme MB sensor for identifying traditional Chinese medicines.Keywords:G-quadruplex DNAzyme;molecular beacon;colorimetric;Pseudostellaria heterophylla
研究领域:
生物化学
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分子生物学
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分析化学
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中药学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2015
·Vol. 182
·期 13
·2131-2138
·
IF 3.741
Xu Jingyue,Li Ying,Bie Jiaxin,Jiang Wei,Guo Jiajia,Luo Yeli,Shen Fei,Sun Chunyan
A sensitive, specific and rapid colorimetric aptasensor for the determination of the plasticizer bisphenol A (BPA) was developed. It is based on the use of gold nanoparticles (AuNPs) that are positively charged due to the modification with cysteamine which is cationic at near-neutral pH values. If aptamers are added to such AuNPs, aggregation occurs due to electrostatic interactions between the negatively-charged aptamers and the positively-charged AuNPs. This results in a color change of the AuNPs from red to blue. If a sample containing BPA is added to the anti-BPA aptamers, the anti-BPA aptamers undergo folding via an induced-fit binding mechanism. This is accompanied by a conformational change, which prevents the aptamer-induced aggregation and color change of AuNPs. The effect was exploited to design a colorimetric assay for BPA. Under optimum conditions, the absorbance ratio of A
527 / A
680 is linearly proportional to the BPA concentration in the range from 35 to 140 ng∙mL −1 , with a detection limit of 0.11 ng∙mL −1 . The method has been successfully applied to the determination of BPA in spiked tap water and gave recoveries between 91 and 106 %. Data were in full accordance with results obtained from HPLC. This assay is selective, easily performed, and in our perception represents a promising alternative to existing methods for rapid quantification of BPA.
The negatively-charged anti-BPA aptamers can absorb onto the positively-charged cysteamine-capped AuNPs (cysteamine-AuNPs) via electrostatic interactions, which can cause the aggregation of AuNPs accompanied by a red-to-blue color change. In the presence of BPA, the specific binding of BPA to the aptamers induces the conformation changes of anti-BPA aptamers, which can release the aptamers from cysteamine-AuNPs and thus prevent the aggregation and color change of cysteamine-AuNPs.
研究领域:
分析化学
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环境科学
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生物技术
✓ 已验证
产品关联
DOI
高影响因子
Foods
·
2021
·Vol. 10
·期 10
·2483
·
IF 4.35
Wenzhi Tang,Yangchun Qi,Zhonghong Li
Food analysis based on the enzyme-linked immunosorbent assay (ELISA) is simple, sensitive and rapid, but requires a costly colorimetric instrument. The aim of this work was to develop a portable, low-cost and user-friendly colorimetric instrument for colorimetric ELISA and aflatoxin B1(AFB1) detection. The principle of the developed instrument was employing a light-emitting diode to generate the signal light and using a light-dependent resistor to measure the signal light absorbed by the oxidized 3,3′,5,5′-tetramethyl benzidine. The absorption spectra revealed that the solution absorbed signal light more strongly after reaction with H2SO4, and blue light would be favorably absorbed. Evaluations on the stability and accuracy of the instrument and interference from ambient light showed that the fabricated instrument was stable, accurate, capable of quantitative detection and insensitive to ambient light changes. In addition, this instrument is user-friendly since it could calculate and report the final amount of AFB1to the operator. Measurements of maize and peanuts showed that the instrument provided as accurate results as the professional equipment. With the low fabrication cost (about RMB 129 or USD 20), portability, and user-friendliness, this instrument presents attractive potential in the rapid detection of AFB1.Keywords:ELISA;colorimetric;food safety;mycotoxin;rapid detection
研究领域:
食品科学
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分析化学
·
仪器仪表
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产品关联
DOI
PubMed
高影响因子
Chemosensors
·
2021
·Vol. 9
·期 12
·335
·
IF 3.398
Chenglong Liao,Miao Zhang,Nan Gao,Qingyun Tian,Jiangfan Shi,Shuai Chen,Chuanyi Wang,Ling Zang
We report on a novel colorimetric sensor system for highly sensitive detection of formaldehyde (FA) in the gas phase. The sensor is constructed with paper towel as a substrate coated with the sulfuric acid salt of hydroxylamine ((NH2OH)2·H2SO4) together with two pH indicators, bromophenol blue and thymol blue. Upon exposure to FA, the hydroxylamine will react with the absorbed FA to form a Schiff base (H2C=N-OH), thus releasing a stoichiometric amount of sulfuric acid, which in turn induces a color change of the pH indicator. Such a color change was significantly enriched by incorporating two pH indicators in the system. With the optimized molar ratio of the two pH indicators, the color change (from brown to yellow, and to red) could become so dramatic as to be visible to the eye depending on the concentration of FA. In particular, under 80 ppb of FA (the air quality threshold set by WHO) the color of the sensor substrate changes from brown to yellow, which can even be envisioned clearly by the naked eyes. By using a color reader, the observed color change can be measured quantitatively as a function of the vapor concentration of FA, which produces a linear relationship as fitted with the data points. This helps estimate the limit of detection (LOD), to be 10 ppb under an exposure time of 10 min, which is much lower than the air quality threshold set by WHO. The reported sensor also demonstrates high selectivity towards FA with no color change observed when exposed to other common chemicals, including solvents and volatile organic compounds. With its high sensitivity and selectivity, the proposed paper-based colorimetric sensor thus developed can potentially be employed as a low-cost and disposable detection kit that may find broad application in detecting FA in indoor air and many other environments.Keywords:vapor detection;formaldehyde;colorimetric;paper-based sensor;hydroxylamine
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2023
·
IF 4.8
Lanlan Li,Xiaoyu Dong,Jihong Chen,Jing Xiao,Li Zeng,Zhengwen Huang,Zhirong Zou
A rapid and easy-used colorimetric method was developed for on-site and rapid analysis of Cr(VI). Under acidic condition, Cr(VI) was reacted with 1, 5-diphenylcarbazide (DPC) and a purple-red complex was formed subsequently, inducing the color changed from colorless to purple-red, this color variance can be detected by ultraviolet–visible spectrophotometer (UV–Vis), smartphone and even naked-eye. For realizing the goal of on-site analysis, this method was integrated in a three dimensional (3D) printed analytical kit, smartphone was used as a portable detector. Under the optimized conditions, limit of detections (LODs) of 0.0014 μg/mL and 0.0016 μg/mL were obtained by smartphone and UV–Vis, respectively. Concentration of Cr(VI) as low as 0.05 μg/mL was still visible by naked-eye. This colorimetric system was further applied to the analysis of several environmental water samples, recoveries of 90–107 % were obtained. It is a promising portable analytical device/system for Cr(VI) on-site and rapid analysis.
研究领域:
环境科学
·
分析化学
✓ 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）