MICROCHIMICA ACTA
·
2024
·Vol. 191
·期 6
·1-13
·
IF 5.3
Qin Xiaoyun,Yin Peijun,Zhang Yuhang,Su Mingxing,Chen Fenghua,Xu Xinru,Zhao Jianbo,Gui Yanghai,Guo Huishi,Zhao Chao,Zhang Zhen
Gold nanomaterials have been widely explored in electrochemical sensors due to their high catalytic property and good stability in multi-medium. In this paper, the reproducibility of the signal among batches of gold nanorods (AuNRs)-modified electrodes was investigated to improve the data stabilization and repeatability. Ordered and random self-assembled AuNRs-modified electrodes were used as electrochemical sensors for the simultaneous determination of dopamine (DA) and topotecan (TPC), with the aim of obtaining an improved signal stability in batches of electrodes and realizing the simultaneous determination of both substances. The morphology and structure of the assemblies were analyzed and characterized by UV–Vis spectra, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray powder diffraction (XRD). Electrochemical studies showed that the ordered AuNRs/ITO electrodes have excellent signal reproducibility among several individuals due to the homogeneous mass transfer in the ordered arrangement of the AuNRs. Under the optimized conditions, the simultaneous detection results of DA and TPC showed good linearity in the ranges 1.75–45 μM and 1.5–40 μM, and the detection limits of DA and TPC were 0.06 μM and 0.17 μM, respectively. The results showed that the prepared ordered AuNR/ITO electrode had high sensitivity, long-term stability, and reproducibility for the simultaneous determination of DA and TPC, and it was expected to be applicable for real sample testing. Graphical Abstract
研究领域:
分析化学
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纳米科学
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生物医学工程
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DOI
PubMed
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2014
·Vol. 407
·期 6
·1595-1605
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IF 3.578
Du Yan,Wu Dapeng,Wu Qian,Guan Yafeng
In this study, the efficiency of five peptide-extraction methods—acetonitrile (ACN) precipitation, ultrafiltration, C18 solid-phase extraction (SPE), dispersed SPE with mesoporous carbon CMK-3, and mesoporous silica MCM-41—was quantitatively investigated. With 28 tryptic peptides as target analytes, these methods were evaluated on the basis of recovery and reproducibility by using high-performance liquid chromatography–triple-quad tandem mass spectrometry in selected-reaction-monitoring mode. Because of the distinct extraction mechanisms of the methods, their preferences for extracting peptides of different properties were revealed to be quite different, usually depending on the pI values or hydrophobicity of peptides. When target peptides were spiked in bovine serum albumin (BSA) solution, the extraction efficiency of all the methods except ACN precipitation changed significantly. The binding of BSA with target peptides and nonspecific adsorption on adsorbents were believed to be the ways through which BSA affected the extraction behavior. When spiked in plasma, the performance of all five methods deteriorated substantially, with the number of peptides having recoveries exceeding 70 % being 15 for ACN precipitation, and none for the other methods. Finally, the methods were evaluated in terms of the number of identified peptides for extraction of endogenous plasma peptides. Only ultrafiltration and CMK-3 dispersed SPE performed differently from the quantitative results with target peptides, and the wider distribution of the properties of endogenous peptides was believed to be the main reason.
Distribution of the recoveries of target peptides after treatment by the five peptide-extraction methods
研究领域:
生物化学
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分析化学
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蛋白质组学
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DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2017
·Vol. 5
·期 32
·16748-16756
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IF 8.867
Mengmeng Shao,Yangfan Shao,Jianwei Chai,Yuanju Qu,Mingyang Yang,Zeli Wang,Ming Yang,Weng Fai Ip,Chi Tat Kwok,Xingqiang Shi,Zhouguang Lu,Shijie Wang,Xuesen Wang,Hui Pan
Photocatalytic water splitting is an environmentally friendly technique for hydrogen production. In this work, we report a novel photocatalyst consisting of two-dimensional (2D) titanium carbide (Ti2C) and graphitic carbon nitride (g-C3N4). We observe substantially enhanced water splitting activities due to the efficient synergistic interaction between Ti2C and g-C3N4. Optimal properties are achieved in the g-C3N4 with a loading of 0.4 wt% Ti2C with a hydrogen production rate of 47.5 μmol h−1, which is 14.4 times as much as that in the case using pure g-C3N4, and it even outperforms Pt-loaded g-C3N4. We further show that the Ti2C/g-C3N4 has high stability and good reproducibility. We expect that the Ti2C/g-C3N4 can be a photocatalyst for large scale applications because both Ti2C and g-C3N4 are low-cost, abundant, and nontoxic.
研究领域:
材料科学
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化学工程
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可再生能源
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DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2020
·
IF 3.99
Xin-Yue Wang,Jie Yang,Ling Zhou,Gao Song,Fan Lu,Li-Jun You,Ju-Mei Li
It is greatly significant to sense hexavalent chromium (Cr (VI)) in water because Cr (VI) is one of the most toxic heavy metals and is extremely harmful for human health and environment. In this study, we explored sensitive surface-enhanced Raman scattering (SERS) substrates for rapid detection of Cr (VI) using magnetic Fe 3 O 4 /ZrO 2 /Ag composite microspheres. We firstly coated uniform zirconium dioxide layer around Fe 3 O 4 cores to achieve Fe 3 O 4 /ZrO 2 microspheres and then deposited silver nanoparticles onto their surface via controlled reduction of AgNO 3 by n-butylamine. The SERS sensitivity of Fe 3 O 4 /ZrO 2 /Ag composite microspheres were easily tailored via facilely changing the concentration of AgNO 3 to tune the coverage of silver nanoparticles on the Fe 3 O 4 /ZrO 2 /Ag. We used 4-mercaptobenzoic acid (4-MBA) as a Raman molecule to evaluate the SERS activity of Fe 3 O 4 /ZrO 2 /Ag. They illustrated excellent SERS property as well as magnetic responsibility. The optimized Fe 3 O 4 /ZrO 2 /Ag were employed to quantitatively detect Cr (VI) in aqueous solution. The results showed good linear relationship between SERS intensities and logarithm concentrations of Cr (VI) (R 2 = 0.98) with a detection limit of low down to 10 −7 M, which is much lower than the safety value (1 μM) in drinking water of United States Environmental Protection Agency. Moreover, the highly uniform and robust Fe 3 O 4 /ZrO 2 /Ag composite microspheres display outstanding signal reproducibility (RSD = 8.34 %) and good storage stability. These results indicate that the prepared Fe 3 O 4 /ZrO 2 /Ag composite microspheres have promising application prospect for SERS analysis of environmental pollutants.
研究领域:
环境科学
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分析化学
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DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2022
·
IF 4.831
Yuanjie Teng,Weihao Huang,Xin Li,Zaifa Pan,Kang Shao
Reproducibility is still a great challenge for surface-enhanced Raman scattering (SERS), because the uncontrollable fabrication of SERS substrates or the uneven distribution of samples on the substrate result in the signal fluctuation with or between the substrates. Herein, a novel SERS quantitative method with good reproducibility was proposed. It is based on the basic principle that the SERS signal intensity is not only related to electromagnetic enhancement and the concentration of sample, but also related to the specific surface area of the substrate. The surface area information of the substrate is obtained through electrochemical technology, and then introduced into the standard curve with the linear relationship of concentration of sample and SERS intensity as a new variable to obtain a 3D standard curved surface, which effectively corrects the signal difference between the substrates, and combines the wide area Raman method to reduce the difference within the substrate, thereby improving the reproducibility of SERS quantitative detection. Using malachite green (MG) as the probe molecule and using cyclic voltammetry to calculate the substrate area fitted plane model (CV-standard curved surface), the root mean square error (RMSE) of the predicted result is 0.26 and the relative error (RE) is 0.25. It shows that the detection error significantly reduces comparing with the traditional standard curve method. Also, the proposed method can be used in other SERS quantitative detection and has potential application prospects.
研究领域:
分析化学
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电化学
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光谱学
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DOI
PubMed
高影响因子
Molecular Plant
·
2021
·Vol. 15
·期 1
·189-202
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IF 13.164
Yuan H,Cao G,Hou X,Huang M,Du P,Tan T,Zhang Y,Zhou H,Liu X,Liu L,Jiangfang Y,Li Y,Liu Z,Fang C,Zhao L,Fernie AR,Luo J
Volatile organic compounds play essential roles in plant environment interactions as well as determining the fragrance of plants. Although gas chromatography-mass spectrometry-based untargeted metabolomics is commonly used to assess plant volatiles, it suffers from high spectral convolution, low detection sensitivity, a limited number of annotated metabolites, and relatively poor reproducibility. Here, we report a widely targeted volatilomics (WTV) method that involves using a "targeted spectra extraction" algorithm to address spectral convolution, constructing a high-coverage MS 2 spectral tag library to expand volatile annotation, adapting a multiple reaction monitoring mode to improve sensitivity, and using regression models to adjust for signal drift. The newly developed method was used to profile the volatilome of rice grains. Compared with the untargeted method, the newly developed WTV method shows higher sensitivity (for example, the signal-to-noise ratio of guaicol increased from 4.1 to 18.8), high annotation coverage (the number of annotated volatiles increased from 43 to 132), and better reproducibility (the number of volatiles in quality control samples with relative standard deviation value below 30.0% increased from 14 to 92 after normalization). Using the WTV method, we studied the metabolic responses of tomato to environmental stimuli and profiled the volatilomes of different rice accessions. The results identified benzothiazole as a potential airborne signal priming tomato plants for enhanced defense and 2-nonanone and 2-heptanone as novel aromatic compounds contributing to rice fragrance. These case studies suggest that the widely targeted volatilomics method is more efficient than those currently used and may considerably promote plant volatilomics studies.
研究领域:
植物学
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分析化学
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代谢组学
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DOI
PubMed
高影响因子
JOURNAL OF ANALYTICAL CHEMISTRY
·
2024
·Vol. 79
·期 5
·644-651
·
IF 1
Shafique Muhammad,Sadiq Nauman,Akbar Muafia,Shakoor Memoona,Mustafa Ghulam
Abstract In this study, a molecularly imprinted co-polymer-based electrochemical sensor has been fabricated that shows sensitive and selective detection of paracetamol. Molecularly imprinted co-polymer synthesis was achieved using methacrylic acid and styrene as functional monomers, azobisisobutyronitrile as a free radical initiator, ethylene glycol dimethacrylate as a cross-linker, and dimethyl sulfoxide as a porogenic solvent. The molecularly imprinted co-polymer was synthesized using a thermal free radical bulk polymerization technique. The molecularly imprinted co-polymer is characterized by Fourier-transform infrared spectroscopy. The LCR meter was used to measure electrical parameters such as inductance and resistance. The sensor response was linear and concentration-dependent. The lower limit of detection of the fabricated sensor in terms of inductance and resistance was 12 and 5.33 mg/L, respectively. Furthermore, in the presence of competing substances such as ascorbic acid and uric acid, the fabricated sensor proved a selective response. The fabricated sensor also shows reproducibility and reversible response.
研究领域:
分析化学
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药物分析
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生物医学工程
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DOI
高影响因子
ANALYST
·
2021
·Vol. 146
·期 23
·7168-7177
·
IF 4.616
Bingyong Lin,Yuanyuan Yao,Yueliang Wang,Palanisamy Kannan,Lifen Chen,Longhua Guo
The uneven distribution of metal nanoparticles is a vital influencing factor in the poor uniformity of surface-enhanced Raman scattering (SERS) substrates, which is a challenge in SERS quantitative analysis. Recent reports showed that the reproducibility of a nonuniform SERS substrate can be effectively improved by the use of an internal standard (IS). However, most of these approaches require the investment of time for precise regulation, and those approaches based on the addition of an IS are specific to a certain substrate. In this work, we proposed a simple, rapid and universal method to incorporate an IS into a SERS substrate for improving the reproducibility of Raman signals based on the systematic evaluation of the influencing factors of the competitive adsorption between the IS and the target analytes. Following the proposed pressure drop-coating (PDC) method, an IS-modified gold nanobipyramids (Au NBPs)/anodic aluminum oxide (AAO) SERS substrate was fabricated within 1 min, showing high reproducibility of Raman signals. In addition, the IS-modified Au NBPs/AAO SERS substrate was successfully applied to analyze thiram in freshly squeezed apple juice and the result showed a stable Raman signal with a relative standard deviation of less than 6.00%. What is more, three different commercial SERS chips were modified with an IS molecule using the PDC method. Compared to the traditional SERS chips, the Raman signal reproducibility of the functionalized SERS chips was improved significantly. Since the addition of an IS is not based on a certain substrate, the proposed approach could be useful for all the researchers working in the field of SERS.
研究领域:
分析化学
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材料科学
·
纳米技术
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产品关联
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2020
·Vol. 187
·期 6
·1-9
·
IF 6.232
Chen Yang,Huang Ailan,Zhang Lu,Bie Zijun
A highly oriented crystalline metal-organic framework (MOF) nanofilm array was prepared and used for surface-assisted laser desorption ionization mass spectrometry (SALDI-MS) for determination of small molecules. The MOF nanofilm was characterized using scanning/transmission electron microscopy, X-ray diffraction, and ultraviolet-visible spectroscopy. Different small molecules (anthracene, n-eicosanoic acid, Rhodamine B) were successfully determined by this MOF nanofilm array with limits of detection (LOD) between 0.1–5 ng·mL −1 and limits of quantification (LOQ) between 1 and 10 ng·mL −1 . Compared to previously reported MOF-based SALDI-MS, this array exhibits better reproducibility (3.3–5.2%) and recovery (89–105%). The intensity of the MS peak remains the same after 25 repeated cycles. This indicates good repeatability. This MOF nanofilm-based SALDI-MS array can be used for determination of fatty acid and Rhodamine B in real samples with good recovery (83–106%).
Schematic representation of the principle of crystalline MOFs nanofilm-based SALDI-MS array
研究领域:
分析化学
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材料科学
·
质谱分析
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产品关联
DOI
PubMed
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2020
·
IF 3.408
Guojun Weng,Yue Yang,Jing Zhao,Jianjun Li,Jian Zhu,Junwu Zhao
The fabrication of paper-based SERS substrates, which provided the advantages of active Raman signal enhancement with good reproducibility is still a challenge for real-world applications. In this report, we showed how the SERS enhancement and reproducibility of Au NP paper substrates prepared by inkjet-printed method could be improved significantly by second growth of Ag NPs. The Au/Ag NP paper substrates fabricated with the improved protocol had a much higher SERS enhancement (about 1.356✕10 3 times) compared with printed Au NP paper substrates. Moreover, the reaction parameters affected the SERS enhancement of Au/Ag NP paper substrates were optimized by collecting rhodamine 6G (R6G) SERS spectra. Further, the reproducibility of Au/Ag NP paper substrates were evaluated on random spots of single substrate and batch to batch substrates by recording the intensity of R6G at 611 cm −1 . The SERS intensities at 611 cm −1 showed small relative standard deviation, which indicated the good reproducibility of Au/Ag NP paper substrates. This improved method enabled the printed Au NP paper substrates to possess the practical applicability for the on-site SERS sensing.
研究领域:
分析化学
·
材料科学
·
纳米技术
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产品关联
DOI
高影响因子
Nanoscale
·
2019
·Vol. 12
·期 7
·4359-4365
·
IF 6.97
Zhen Wang,Chunxue Zheng,Peng Zhang,Zhulin Huang,Chuhong Zhu,Xiujuan Wang,Xiaoye Hu,Jian Yan
Herein, we report a facile strategy of combined SERS measurements based on a split-type SERS substrate, which exhibits excellent SERS activity, detection signal reproducibility and chemical stability. The SERS substrate consists of an ordered Al2O3@Ag@Si nanocone array and Ag nanoparticles (Ag-NPs), both of which are fabricated individually. The Al2O3@Ag@Si nanocone array is obtained by ion-sputtering Ag on an Si nanocone array and then coating an ultrathin (∼2 nm) Al2O3 dielectric layer via atomic layer deposition (ALD). Ag-NPs are synthesized via the liquid phase method and then immersed in an organic solvent for liquid seal. For the SERS measurement, Ag-NPs are dispersed in a liquid containing the probe molecules and then, they self-assemble on the surface of the Al2O3@Ag@Si nanocones. Subsequently, the ultrathin Al2O3 dielectric layer separates Ag-NPs from the Ag@Si nanocones, forming massive gap-introduced hot spots. This substrate is sensitive to 1 pM Rhodamine R6G with an average enhancement factor of up to 109, exhibiting excellent SERS activity. Moreover, due to the protection of the Al2O3 dielectric layer and the organic solvent for the Ag@Si nanocones and Ag-NPs against oxidation, the split-type SERS substrate achieves an SERS signal with almost no attenuation after five months, indicating its good chemical stability.
研究领域:
材料科学
·
分析化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF SEPARATION SCIENCE
·
2021
·Vol. 44
·期 17
·3324-3332
·
IF 3.645
Yang Huang,Zhengjin Jiang
A poly( N , N -dimethyl- N -methacryloyloxyethyl- N -(3-sulfopropyl) ammonium betaine- co -ethylene dimethacrylate) monolith was prepared in a 100 × 2.0 mm id stainless-steel column and was investigated for supercritical fluid chromatography. Optimization of its porosity was performed by changing the conditions of polymerization. Then, the chemical group of this column was confirmed by Fourier transform infrared spectroscopy and elemental analysis. The morphology was characterized by scanning electron microscopy. The prepared column showed good repeatability based on the retention factor of adenine, uracil and cytosine to calculate their run-to-run, day-to-day, column-to-column, and batch-to-batch relative standard deviations. Those values were less than 1.9% ( n = 10), 6.5% ( n = 3), 5.6% ( n = 3), and 1.7% ( n = 3), respectively. In addition, the column was found to be stable within 3 and 10 days with relative standard deviations less than 6.5 and 8.5%, respectively. These results indicated that the columns showed good reproducibility and stability. Compared with liquid chromatogaphy, supercritical fluid chromatography provided better kinetic performance and selectivity. Finally, several neutral, acid, and basic polar analytes were utilized to test its application. The results demonstrated that the prepared column exhibited a good separation performance and showed great potential in supercritical fluid chromatography.
研究领域:
分析化学
·
色谱技术
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DOI
高影响因子
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