JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2011
·
IF 2.733
Wei Gong,Zhi-Yu Dou,Ping Liu,Xue-Ying Cai,Xing-quan He
The novel covalently modified glassy carbon electrode with polyethylene oxide has been prepared using an electroadsorption method for the simultaneous determination of dopamine (DA) and ascorbic acid (AA). This new electrode presented an excellent electrocatalytic activity towards the oxidation of DA and AA by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods. The separation potentials of the oxidation peak potentials for them were about 155 mV in CV and 216 mV in DPV. The differences are large enough to determine DA and AA individually and simultaneously. Calibration curves in the ranges of 5.0–40 and 300–1700 μmol L −1 were obtained for DA and AA, respectively. The lowest detection limits (S/N = 3) were 0.25 and 50 μmol L −1 for DA and AA, respectively.
研究领域:
分析化学
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电化学
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产品关联
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2013
·
IF 2.672
Yangyang Gao,Huan Wang,Liping Guo
In this work, a glassy carbon electrode (GCE) modified with large mesoporous carbon and Nafion composites (LMC/Nafion) was constructed and used for simultaneous determination of theophylline (TP) and caffeine (CF). The electrochemical behaviors of TP and CF on the LMC/Nafion/GCE were carefully investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The results show that the DPV peaks of the two analytes can be distinguished at the modified electrode with peak-to-peak separation about 150 mV, which means that LMC/Nafion/GCE is suitable for simultaneous determination of TP and CF. Under the optimized condition, the detection limits of TP and CF were 0.37 and 0.47 μM ( S / N = 3) with linear ranges of 0.8–180.0 μM and 1.3–230.0 μM, respectively. The proposed method was successfully applied to the simultaneous determination of TP and CF in human blood serum and beverages with reliable recovery.
研究领域:
分析化学
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电化学
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产品关联
DOI
高影响因子
MOLECULES
·
2019
·Vol. 24
·期 8
·1494
·
IF 3.06
Ruiqin Zhu,Ying Dong,Xiangyang Cai,Chuixiu Huang
The wide abuse of barbiturates has aroused extensive public concern. Therefore, the determination of such drugs is becoming essential in therapeutic drug monitoring and forensic science. Herein, a simple, efficient, and inexpensive sample preparation technique, namely, flat membrane-based liquid-phase microextraction (FM-LPME) followed by liquid chromatography-mass spectrometry (LC-MS), was used to determine barbiturates in biological specimens. Factors that may influence the efficiency including organic extraction solvent, pH, and composition of donor and acceptor phases, extraction time, and salt addition to the sample (donor phase) were investigated and optimized. Under the optimized extraction conditions, the linear ranges of the proposed FM-LPME/LC-MS method (with correlation coefficient factors ≥ 0.99) were 7.5–750 ng mL−1for whole blood, 5.0–500 ng mL−1for urine, and 25–2500 ng g−1for liver. Repeatability between 5.0 and 13.7% was obtained and the limit of detection (LOD) values ranged from 1.5 to 3.1 ng mL−1, from 0.6 to 3.6 ng mL−1, and from 5.2 to 10.0 ng g−1for whole blood, urine, and liver samples, respectively. This method was successfully applied for the analysis of barbiturates in blood and liver from rats treated with these drugs, and excellent sample cleanup was achieved.Keywords:membrane-based microextraction;barbiturates;simultaneous determination;whole blood;urine;liver
研究领域:
分析化学
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法医学
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药物分析
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产品关联
DOI
PubMed
高影响因子
Foods
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2023
·Vol. 12
·期 15
·2875
·
IF 5.2
Yibo Dong,Xiaolong Yao,Wanping Zhang,Xiaomao Wu
3,4-dichloroaniline (3,4-DCA) and 3,5-dichloroaniline (3,5-DCA) are, respectively, the primary metabolites deriving from the breakdown of phenylurea herbicides and dicarboximide fungicides in both soils and plants, whose residues in vegetable products have a heightened concern considering their higher health risks to humans and greater toxicity than the parent compounds in the environment. In this study, a sensitive high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for the simultaneous determination of 3,4-DCA and 3,5-DCA residues in chive products based on the optimization of HPLC-MS/MS chromatographic and mass-spectrometric conditions using the standard substances and the modified QuEChERS preparation technique. The preparation efficiency of 3,4-DCA and 3,5-DCA from chive samples showed that acetonitrile was the best extractant. The combination of the purification agent graphite carbon black + primary secondary amine and the eluting agent acetonitrile + toluene (4:1,v/v) had a satisfactory purification effect. The linear correlation coefficients (R2) were more than 0.996 with the six concentration range of 0.001–1.000 mg/L for 3,4-DCA and 3,5-DCA. The limit of detection and limit of quantitation of this method was 0.6 and 2.0 µg/kg for 3,4-DCA, as well as 1.0 and 3.0 µg/kg for 3,5-DCA, respectively. The matrix effect range of 3,4-DCA and 3,5-DCA in chive tissues was from −9.0% to −2.6% and from −4.4% to 2.3%, respectively. The fortified recovery of 3,4-DCA and 3,5-DCA in chive samples at four spiked levels of 0.001–1.000 mg/kg was 75.3–86.0% and 78.2–98.1%, with the relative standard deviation of 2.1–8.5% and 1.4–11.9%, respectively. The limit of detection (LOD) and limit of quantification (LOQ) of the method were 0.6, 2.0, and 1.0, 3.03 for 4-DCA and 3,5-DCA, respectively. This study highlights that the analytical method established here can efficiently and sensitively detect residues of 3,4-DCA and 3,5-DCA residues for monitoring chive products. The method was successfully applied to 60 batches of actual vegetable samples from different regions.Keywords:3,4-dichloroaniline;3,5-dichloroaniline;simultaneous determination;UPLC-MS/MS;chive
研究领域:
分析化学
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食品安全
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Rui Cheng,Yiqun Wan,Xuejin Mao,Hao Wan,Fan Liu,Lan Guo,Bingzhen Zhang
This work presents an efficient sorbent for plant growth regulators (PGRs) by regulating the defects of a metal–organic framework MIL-101(Cr). Using the regulated MIL-101(Cr), we developed a simple and effective method for the simultaneous determination of eleven PGRs in fresh fruit juice. The extraction conditions were optimized by an orthogonal array design. Under optimal conditions, the method showed a satisfactory limit of detection (0.1–1.2 ng/g), recovery rates (83.4–110.2 %), and precision (2.9–18.0 % for intra-day and 2.7–10.8 % for inter-day), as well as a greatly suppressed matrix effect. Notably, regulating the defects significantly enhanced the desorption of PGRs on MIL-101(Cr). The sorbent didn’t need to be destroyed to release the adsorbed PGRs and could be reused at least 6 times. Furthermore, the defects of MIL-101(Cr) and interactions between the sorbent and PGRs were studied by TGA, ATR-IR, XPS, NH 3 -TPD and UV–Vis DRS.
研究领域:
分析化学
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食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS
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2019
·Vol. 19
·期 10
·2289
·
IF 3.031
Lina Abdullah Alshahrani,Liqiong Miao,Yanyu Zhang,Shengming Cheng,Palanivel Sathishkumar,Balasubramaniam Saravanakumar,Junmin Nan,Feng Long Gu
A copper sulfide nanoflakes-decorated carbon nanofragments-modified glassy carbon electrode (CuS-CNF/GCE) was fabricated for the electrocatalytic differentiation and determination of hydroquinone (HQ) and catechol (CC). The physicochemical properties of the CuS-CNF were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Raman spectroscopy. The electrocatalytic determination of HQ and CC over the CuS-CNF/GCE was evaluated by cyclic voltammetry and differential pulse voltammetry. An excellent detection limit and sensitivity of the CuS-CNF/GCE are obtained (0.293 µM and 0.259 µM) with a sensitivity of 184 nA µM−1cm−2and 208 nA µM−1cm−2(S/N=3) for HQ and CC, respectively. In addition, the CuS-CNF/GCE shows a selective identification of HQ and CC over potential interfering metal ions (Zn2+, Na+, K+, NO3−, SO42−, Cl−) and organic compounds (ascorbic acid, glucose), and a satisfactory recovery is also obtained in the spiked water samples. These results suggest that the CuS-CNF/GCE can be used as an efficient electrochemical sensor for the simultaneous determination of co-existing environmental pollutants such as HQ and CC in water environments with high selectivity and acceptable reproducibility.Keywords:carbon nanofragments;copper sulfide;catechol;hydroquinone;electrochemical sensor;simultaneous determination
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
INTERNATIONAL JOURNAL OF ENVIRONMENTAL ANALYTICAL CHEMISTRY
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2015
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IF 1.295
Jing Zhang,Shibo Zhang,Xue Wang,Wenchang Wang,Zhidong Chen
A convenient and sensitive method was developed for the simultaneous determination of Ponceau-4R and Allura Red using an ionic liquid modified expanded graphite paste electrode (IL-EGPE). The IL-EGPE was prepared by mixing ionic liquid-expanded graphite (IL-EG) composites with solid paraffin. Based on the advantageous functions of IL and EG, IL-EGPE showed enhanced electrocatalytic activity towards the simultaneous oxidation of Ponceau-4R and Allura Red. Under optimal experimental conditions, the IL-EGPE exhibited wide linear responses to Ponceau-4R and Allura Red ranging from 6.0 to 7.5 mg L−1 and 5.0 to 0.5 mg L−1, respectively. The detection limits for Ponceau-4R and Allura Red were 1.15 and 0.89 μg L−1 at a signal-to-noise ratio of 3, respectively. The designed electrode showed good reproducibility, stability and reusability. The proposed method was successfully applied in the simultaneous determination of Ponceau-4R and Allura Red in soft drinks. This method presented a simple, rapid and sensitive platform for simultaneous determination of Ponceau-4R and Allura Red and would become a versatile and powerful tool for food safety.
研究领域:
分析化学
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食品安全
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产品关联
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2025
·
IF 4
Wen Huang,Xiaoting Li,Feifang Zhang,Yufeng Shen,Bingcheng Yang
This study presents a simultaneous determination method for common corrosion-mark cations (Li⁺, NH₄⁺, monoethanolamine, Zn²⁺, and Cd²⁺) in nuclear power plant water. The analysis employs conductometric ion chromatography combined with a custom-built liquid core waveguide capillary scale fluorescence detector. Monovalent cations (Li⁺, NH₄⁺, monoethanolamine) were detected conductometrically with detection limits of 56–108 nM, while divalent heavy metals (Zn²⁺, Cd²⁺) were specifically quantified through the fluorescence detector, achieving detection limits of 42 nM and 33 nM, respectively. The method demonstrates good analytical performance, as indicated by the spiked recoveries ranging from 88.50 % to 128.54 % and relative standard deviations between 0.10 % and 4.16 % for all target analytes.
研究领域:
分析化学
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核能工程
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产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2015
·
IF 4.097
Weihua Cai,Jianwei Lai,Ting Lai,Haoting Xie,Jianshan Ye
Flexible graphene fibers were controlled synthesized and further functionalized by NiCo 2 O 4 nanowires. The novel sensors were used directly as working electrode for the simultaneous determination of ascorbic acid (AA), dopamine (DA), and uric acid (UA). The detection limits (S/N = 3) of 50 μM, 0.1 μM, 0.2 μM were obtained for AA, DA and UA in PBS, respectively. Due to the synergistic effect between the high conductivity of graphene fiber and the catalytic activity of NiCo 2 O 4 , the as-prepared composite fibers showed excellent performance. This research may offer new ways to synthesize graphene based fibers for the determination of molecules.
研究领域:
材料科学
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分析化学
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生物医学工程
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产品关联
DOI
高影响因子
TALANTA
·
2016
·
IF 4.035
Jing Chen,Bao Qiong Li,Min Li Xu,Xue Wang,Yu Hong Jing,Hong Lin Zhai
The interference signals and overlapped peaks are common phenomena in fluorescence determination, which seriously influence the accuracy and reliability of analytical results. In this paper, Krawtchouk image moment method was introduced to the analysis of fluorescence three-dimensional (3D) spectra and applied to the quantitative analysis of three drugs including nicotinic acid, metoprolol and amlodipine in human plasma. Without any pretreatment to the obtained spectra, Krawtchouk moments were directly calculated on the grayscale images of 3D spectra, and the quantitative linear models for the three drugs were established by stepwise regression, respectively. The determination coefficients ( R ) were more than 0.9906. The correlation coefficients of leave-one-out cross-validation ( R cv ) were more than 0.9256. The precisions (RSD, %) of inter-day and intra-day variations were less than 8.4% and 3.1%, separately. The recovery was from 101.84% to 107.88%. The limit of quantification and the limit of detection were 0.12 μg mL −1 and 0.43 μg mL −1 , respectively. All the statistical parameters supported that the obtained models performed well and the proposed method was accurate and reliable. Our study indicates that Krawtchouk image moments with the powerful abilities of multi-resolution and extracting local information can be applied to the simultaneous determination of multi-target compounds in plasma based on fluorescence 3D spectra.
研究领域:
分析化学
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药理学
·
医学检测
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF SEPARATION SCIENCE
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2017
·Vol. 41
·期 2
·440-448
·
IF 2.557
Mengmeng Chen,Guohua Zhu,Shanshan Wang,Kezhi Jiang,Jiaxiang Xu,Jinsong Liu,Jianxiong Jiang
The chromatographic separation of several isomeric anilines is a challenging issue. Herein, a simple method for the simultaneous determination of four groups of isomeric primary aromatic amines, including chloroanilines, methylanilines, methoxylanilines, and dimethylanilines, was presented. In this method, all of the 15 primary aromatic amines were easily transformed into the corresponding imine derivative by treatment with benzaldehyde under mild conditions. The formed isomeric imine derivatives were completely separated on a commercial capillary gas chromatography column. The effects of several derivatization parameters were investigated and optimized. Linearity in the optimized method ranged from 0.050 to 50 μg/mL with the squared correlation coefficients ( R 2 ) between 0.9981 and 0.9999. Reasonable reproducibility was obtained, with the intraday relative standard deviation ( N = 5) ranging from 0.89 to 4.57% and interday relative standard deviation ranging from 2.26 to 7.69% at the concentration of 5.0 μg/mL. The developed method has been successfully applied to determine these isomeric aromatic amines in real samples.
研究领域:
分析化学
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2013
·Vol. 180
·期 5
·461-468
·
IF 3.434
Ma Xuemei,Liu Zhaona,Qiu Cuicui,Chen Ting,Ma Houyi
We have synthesized a virtually monodisperse gold-graphene (Au-G) nanocomposite by a single-step chemical reduction method in aqueous dimethylformamide solution. The nanoparticles are homogenously distributed over graphene nanosheets. A glassy carbon electrode was modified with this nanocomposite and displayed high electrocatalytic activity and extraordinary electronic transport properties due to its large surface area. It enabled the simultaneous determination of hydroquinone (HQ) and catechol (CC) in acetate buffer solution of pH 4.5. Two pairs of well-defined, quasi-reversible redox peaks are obtained, one for HQ and its oxidized form, with a 43 mV separation of peak potentials (ΔE p ), the other for CC and its oxidized form, with a ΔE p of 39 mV. Due to the large separation of oxidation peak potentials (102 mV), the concentrations of HQ and CC can be easily determined simultaneously. The oxidation peak currents for both HQ and CC increase linearly with the respective concentrations in the 1.0 μM to 0.1 mM concentration range, with the detection limits of 0.2 and 0.15 μM (S/N = 3), respectively. The modified electrode was successfully applied to the simultaneous determination of HQ and CC in spiked tap water, demonstrating that the Au-G nanocomposite may act as a high-performance sensing material in the selective detection of some environmental pollutants.
Au-graphene (Au-G) nanocomposites were synthesized through a single-step chemical reduction method. Nearly monodispersed Au nanoparticles were uniformly distributed over the 2D graphene nanosheets without aggregation. The glassy carbon electrode modified with Au-G nanocomposites, Au-G/GCE, shows high resolution capability in simultaneous determination of hydroquinone (HQ) and catechol (CC) in acetate buffer solutions (HAc-NaAc, pH 4.5).
研究领域:
分析化学
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环境科学
·
材料科学
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DOI
高影响因子
危险品化学品经营许可证（带存储）