RAPID COMMUNICATIONS IN MASS SPECTROMETRY
·
2024
·Vol. 39
·期 6
·e9974
·
IF 1.8
Jianhua Lin,Xiaoguang Gao,Jian Jia,Xiuli He
Rationale Exhaled breath can be used for early warning of disease, with organic nitrogen compounds, including triethylamine (TEA), being linked to various medical conditions. Surface ionization ion mobility spectrometry (SI-IMS) facilitates the direct detection of TEA in exhaled breath. However, the presence of multiple ionization products of TEA poses challenges for both quantitative and qualitative analyses. Methods A doped surface ionization (DSI) method consisting of surface ionization of dopants and gas-phase reaction of samples was proposed, and TEA was detected when combined with an ion mobility spectrometer. TEA at different concentrations and spiked by human breath was detected to evaluate the method's properties. Results TEA with concentrations from 5.99 to 30.50 ppb and a relative humidity of 80% was detected. The peak intensity of the protonated TEA ions demonstrated a linear correlation with concentration, yielding a fitted correlation coefficient of R 2 = 0.94. A standard deviation less than 0.066% was obtained with 10 replicate analyses of 29.92 ppb TEA, and the recovery rate of the sample was 93.57%. Conclusions The SI-IMS based on the DSI method has the advantages of excellent selective ionization, high accuracy and sensitivity, and remarkable repeatability for detecting TEA. It is a promising method for detecting specific organic nitrogen compounds in exhaled breath.
研究领域:
医学诊断
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RAPID COMMUNICATIONS IN MASS SPECTROMETRY
·
2013
·Vol. 28
·期 3
·256-264
·
IF 2.509
Xiaoqiang Qiao,Rui Wang,Hongyuan Yan,Tao Wang,Qun Zhao,Lihua Zhang,Yukui Zhang
RATIONALE Chemical derivatization is a very promising technique for improving analysis of peptides by mass spectrometry (MS). In this study, a novel kind of imidazolium-based aromatic quaternary ammonium tag, 1-[3-[(2-iodo-1-oxoethyl)amino]propyl]-3-butylimidazolium bromide (IPBI), designed with strong gas-phase basicity and a permanent positive charge, was firstly synthesized and further used for derivatization of cysteinyl-peptides with improved ionization efficiency and higher charge states. METHODS Both the model peptides and tryptic digests of proteins were used to evaluate the effect of IPBI derivatization on the MS performance of the derivatized peptides, and the results were further compared with the commonly used iodoacetamide (IAA) tag. Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF)-MS and electrospray ionization (ESI)-MS were used to evaluate the ionization efficiency and charge states of the derivatized peptides. RESULTS With model peptides as samples, a nearly 100% derivatization efficiency and superior stability were achieved via IPBI derivatization. By further analysis of both standard peptides and tryptic protein digests, the ionization efficiency and charge states of IPBI-derivatized peptides could be remarkably improved. For example, for protein bovine serum albumin, compared with the commercial available IAA tag, the identification efficiency of cysteinyl-peptides was increased about 67% by combining with IPBI derivatization. CONCLUSIONS The results indicated that the novel tag is an effective derivatization reagent for cysteinyl-peptide identification. We hope it could be further used for high-efficiency cysteinyl-peptide identification in proteome research, especially those with low abundance and poor ionization efficiency. Copyright © 2013 John Wiley & Sons, Ltd.
研究领域:
蛋白质组学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TALANTA
·
2018
·
IF 4.244
Dongqin Tan,Jing Jin,Longxing Wang,Xueqin Zhao,Cuicui Guo,Xiaoli Sun,Dhanjai,Xianbo Lu,Jiping Chen
As one of the most important analytical techniques for accurate quantification of bisphenol compounds, liquid chromatography coupled to online electrospray ionization (ESI) tandem mass spectrometry exhibits relative weak ESI response in negative mode, which greatly reduces their sensitivity and limits their detection at trace levels, especially in complex samples such as blood. Based on the facilitated deprotonation of bisphenol molecule under alkaline condition, post-column injection of ammonium hydroxide (NH 3 ·H 2 O) to mass spectrometer was explored to enhance the ionization efficiency of BPA and its eight analogs and improve their analytical sensitivity. Parameters effecting response intensity and stability were investigated, including mass concentration and flow rate of NH 3 ·H 2 O. Under the optimal conditions with the addition of 2% (w/w) of NH 3 ·H 2 O at 4 μL min −1 , the instrument detection limits for bisphenol compounds were greatly lowered to 0.001–0.04 ng mL −1 , which were 2–28.6 times lower than the result obtained without injecting NH 3 ·H 2 O, except TBBPA (0.03 ng mL −1 in either case). The relative standard deviations (RSDs) for instrument repeatability of BPA and its analogs at three different concentration levels were in a range of 1.2–20%. Furthermore, a decreased matrix effects (90–111%) for bisphenols (except TBBPA) analysis in serum extracts were found compared with the result obtained without NH 3 ·H 2 O injection (43–111%). The results demonstrated that the improved instrumental method coupled with suitable pretreatment techniques is more feasible to analyze bisphenol compounds in complex bio-samples.
研究领域:
分析化学
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环境科学
·
毒理学
✓ 已验证
DOI
PubMed
高影响因子
Journal of the American Chemical Society
·
2020
·
IF 14.612
Zhuang Hu,Shaojie Liu,Haiyan Qin,Jianhai Zhou,Xiaogang Peng
By taking advantage of well-defined spectroscopic signatures of high-quality CdSe/CdS core/shell QDs, the effects of oxygen on photoluminescence (PL) of QDs were studied systematically and quantitatively at both single-dot and ensemble (on substrate and in solution) levels, which reveals a unified yet simple picture. With a sufficient amount of oxygen in the system during photoexcitation, the core/shell QDs in all forms would be deionized timely from the photogenerated and inefficient trion state back to the efficient single-exciton state, with superoxide radicals as the reduction product of oxygen. Under a given excitation power, rates of both spontaneous deionization and photodeionization channels increased by increasing the oxygen pressure, but photoionization of the QDs was barely affected by the oxygen pressure. While stabilizing PL by oxygen was identified for both CdSe plain core and CdSe/CdS core/shell QDs, irreversible photocorrosion was only observed for CdSe plain core QDs, suggesting the importance of high-quality epitaxial shells for QDs in various applications.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
RAPID COMMUNICATIONS IN MASS SPECTROMETRY
·
2010
·Vol. 24
·期 9
·1335-1342
·
IF 2.695
Zhongyue Zhou,Lidong Zhang,Mingfeng Xie,Zhandong Wang,Dongna Chen,Fei Qi
Absolute photoionization and dissociative photoionization cross-sections of eleven n- alkanes ( n- pentane, n -hexane, n- heptane, n- nonane, n- decane, n -undecane, n- dodecane, n- tridecane, n- tetradecane, n- pentadecane and n- hexadecane), three cyclo -alkanes (cyclopentane, methylcyclohexane and trans -decahydronaphthalene) and iso -octane were measured for photon energies from the ionization thresholds to 11.5 eV. The measurements were performed with the binary-liquid-mixture method utilizing the photoionization cross-sections of benzene as a calibration standard. The ionization energies of n -alkanes and cyclo -alkanes were also calculated at the B3P86/6-31 + +G(d,p) level and by the G3B3 method. Copyright © 2010 John Wiley & Sons, Ltd.
研究领域:
化学
·
物理化学
✓ 已验证
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2016
·Vol. 41
·期 3
·1103-1109
·
IF 3.277
Hongmei Yang,Ge Gao,Yihan Wang,Jinrong Liu,Zongjun Li,Rui Su,Bing Wang,Wenhui Lian,Xinhua Guo,Shuying Liu
Glycosides, which are widely distributed in many plants, possess numerous biological activities. Direct analysis in real time (DART) allows the rapid analysis of samples or objects in their native state in the open environment. The ionization characteristics of glycosides by DART, however, have not yet been investigated in detail. DART quadrupole-time of flight mass spectrometry (DART-Q-TOF-MS) was developed to investigate the ionization characteristics of different kinds of glycosides in both positive and negative ion modes. All the glycosides were ionized via various different reactions including (de)protonation, molecular ion formation, ISD fragmentation, and the formation of adducts. In contrast, glycosidic cleavage ions and molecular ions (radical ions) were easily detected in negative DART mass spectra by the capture of an electron. The degree of glycosidic cleavage varied with the structural properties of individual glycosides, which were substantiated by theoretical calculations using the software package Gaussian 09. Temperature and types of DART gas played important roles in DART mass spectrometric analysis of glycosides.
研究领域:
分析化学
·
植物化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2019
·
IF 7.015
Liang Shen,Ming Yi,Lian Tian,Fangqian Wang,Chun Ding,Shipeng Sun,Ang Lu,Li Su,Yan Wang
Membrane-based forward osmosis (FO) technology has attracted increasing interest in the field of water treatment due to its high economical and separation efficiency. However, the availability of a FO membrane with superior separation and antifouling properties is still the critical issue for its real application in wastewater purification. In this work, novel thin-film composite (TFC) membranes are developed by surface ionization with various metal ions and subsequent metallization with the assistance of pre-grafted polyethyleneimine (PEI) and N -containing organic phosphonic acid (OPA), where the latter provides abundant and stable complexing sites. The grafting of hydrophilic PEI/OPA and the attachment of silver atoms endow the resulting membrane a dual defensive and offensive functionality associated with anti-adhesive property and antibacterial activity, respectively. Compared with the control TFC membrane, the surface-modified membranes show significantly improved anti-adhesive property against bovine serum albumin (BSA) and antibacterial property against S. aureus and E. coli bacteria, and thereby improved antifouling property towards the local lake water. Additionally, compared with the silver-metalized TFC membranes prepared by the direct method or indirect PEI binding, the silver-metalized membrane prepared by the indirect OPA binding exhibits a much higher silver loading (34.38 μg/cm 2 ), as well as better, more stable and long-term antibacterial property. Moreover, compared with the control membrane, the modified membranes also have much higher water fluxes (87–141% increase) and comparable or even lower reverse salt fluxes. The influences of the metal ion type used for ionization and the method used for metallization are systematically investigated.
研究领域:
材料科学
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环境工程
·
水处理技术
✓ 已验证
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2025
·
IF 5.1
Jie Wang,Yuan-Yuan Zhang,Dan Liu,Chen-Chun Zhong,Ya-Hui Hu,Fei Zhao,Hong-Li Guo,Feng Chen
The balance of oxalic acid in the body is intricately regulated. Importantly, elevated levels of oxalic acid in urine or blood have been linked to the progression of various diseases. There is strong interest in developing efficient methods to quantify oxalic acid in various bio-matrices like urine. However, due to its small molecular weight, high polarity, acidic nature, and endogenous properties, establishing an analysis method based on liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) for oxalic acid presents significant challenges, and such analysis methods that meet clinical needs are not widely available. Faced with the aforementioned challenging issues, in this study, we have discovered innovative strategies to improve the ionization, chromatographic separation, and enrichment of oxalic acid and its internal standard, leading to the successful LC-MS/MS method development and clinical application of the analysis method. These include: (1) simultaneous use of two low concentrations of electrolytes (NH 3 ·H 2 O and NH 4 Ac) in the mobile phase; (2) alkalinization of urine; (3) addition of 0.3 % NH 3 ·H 2 O to the internal standard oxalic acid-1,2- 13 C solution; (4) selection of ultrapure water (UPW) as an alternative matrix; (5) urine sample processing using an easy-to-use protein precipitation method. These measures have created a relatively homogeneous alkaline environment, addressing the issues in the ionization, chromatographic separation, and enrichment of oxalic acid and its internal standard. Of note, chromatographic separation of oxalic acid and oxalic acid-1,2- 13 C was achieved on the Waters Symmetry C18 column (4.6 mm × 50 mm, 3.5 μm) with an isocratic elution at a flow rate of 0.40 mL/min. The target analyte was completely separated by elution with 30 % acetonitrile containing 0.01 % NH 3 ·H 2 O and 1 mM NH 4 Ac for 3 min, without any endogenous interference. The method showed good linearity over the 0.020–50.0 μg/mL concentration range with a correlation coefficient r 2 = 0.9998. The intra-assay and inter-run precision and accuracy, recovery, and stability of the method were all within the acceptable parameters. Collectively, this study developed and validated a simple, fast, and sensitive LC-ESI-MS/MS method that did not require complex derivatization, acidification, large-volume sample consumption. Moreover, this method was successfully applied for routine urinary oxalic acid detection in children with kidney disease, providing valuable information for clinicians.
研究领域:
临床医学
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分析化学
·
肾脏病学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF MASS SPECTROMETRY
·
2014
·
IF 2.227
Y.Y. Wang,X. Kang,Y.W. Liu,W.Q. Xu,L. Wang,C.Z. Hu,J. Chen,F.Y. Liu,L.S. Sheng,X.L. Zhao,P.F. Zhang,L.F. Zhu
Using vacuum ultraviolet photons produced by synchrotron radiation and reflection time-of-flight mass spectrometer, dissociative photoionization of isooctane was measured in the photon energy region of 9.7–15.6 eV under ultrasonic molecular beam. Then the dissociative ionization products at different photon energies were obtained. By measuring the photoionization efficiency curves, the appearance potentials of the dominative ion fragments and the vertical ionization energy of isooctane were determined. In addition, combining with G3 calculations we obtained the structure and energy of the parent, neutral and ion fragments. By comparing the experimental measurements with the theoretical calculations, the dissociative photoionization channels of isooctane were elucidated, and formation enthalpies of the fragmented ions and the dissociation energy of the parent ion were obtained.
研究领域:
化学物理
·
分子光谱学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2025
·
IF 8.5
Haicun Yang,Mingyue Shi,Wenzhong Ma,Xudong Ma,Jinglong Zhang,Kaide Wu,Zheng Cao,Fanghong Gong,Qiuyan Bi
To overcome low adsorption capacity, slow adsorption rate, poor adsorption selectivity, and dissolution of peach gum polysaccharide (PGP), an amino-rich crosslinked PGP (ACPGP) was first synthesized by cross-linking highly soluble PGP. Subsequently, a cation-rich PGP (QCPGP) was prepared from ACPGP through the addition of glycidyltrimethyl ammonium chloride (GTAC) and a secondary quaternization. The step-by-step preparation process was confirmed, and the adsorption properties of PGP, ACPGP, and QCPGP were compared in detail. The adsorption of crude PGP for cationic dyes violet (MV, 135.0 mg/g) and methylene blue (MB, 121.4 mg/g) were spontaneous endothermic, following the pseudo-first-order kinetic model and D-R isotherm. Due to the presence of rich charged groups in their structure, their highly selective adsorption towards new coccine (NC) and tartrazine (TTZ) is spontaneous and endothermic, and can be described by the pseudo-first-order and pseudo-second-order kinetic models, respectively. According to the Langmuir isotherm, the Q m of ACPGP and QCPGP for NC and TTZ was calculated to be 876.2 and 1304.3 mg/g (NC), and 814.5 and 1136.7 mg/g (TTZ), respectively. QCPGP exhibited more advantages in terms of adsorption capacity, adsorption rate (equilibrium time of 10 min), environmental stability, adsorption selectivity, and regeneration efficiency, showing great potential in practical wastewater treatment applications.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2022
·
IF 10.723
Xiaoxiang Han,Zhehao Zheng,Chen Yu,Yunli Deng,Qing Ye,Fuge Niu,Qing Chen,Weichun Pan,Yanbo Wang
In order to improve the solubility and antibacterial activity of chitosan and expand its application range, ionized chitosan (ICS) was successfully synthesized from chitosan through methylation and sulfonation reactions in this study. The chemical structures of the polymers were verified by Fourier transform infrared spectroscopy (FTIR) and 1 H NMR, and a series of characterizations of the polymer were carried out by analytical methods such as element analysis (EA), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The results showed that the water solubility of the modified ICS was significantly improved. The introduction of propyl sulfonic acid groups with particle size decreasing and potential increasing greatly improved the antibacterial activity of chitosan, indicating that the ICS had the potential as a water-soluble antibacterial agent .
研究领域:
材料科学
·
生物医学
✓ 已验证
DOI
PubMed
高影响因子
Micromachines
·
2021
·Vol. 12
·期 9
·1034
·
IF 2.891
Lvhan Zhou,Qian Zhang,Xiangchun Xu,Xinming Huo,Qian Zhou,Xiaohao Wang,Quan Yu
The coupling of the microfluidic chip to mass spectrometry (MS) has attracted considerable attention in the area of chemical and biological analysis. The most commonly used ionization technique in the chip–MS system is electrospray ionization (ESI). Traditional chip-based ESI devices mainly employ direct electrical contact between the electrode and the spray solvent. In this study, a microchip ESI source based on a novel polarization-splitting approach was developed. Specifically, the droplet in the microchannel is first polarized by the electric field and then split into two sub-droplets. In this process, the charge generated by polarization is retained in the liquid, resulting in the generation of two charged droplets with opposite polarities. Finally, when these charged droplets reach the emitter, the electrospray process is initiated and both positive and negative ions are formed from the same solution. Preliminary experimental results indicate that the coupling of this polarization-splitting ESI (PS-ESI) chip with a mass spectrometer enables conventional ESI-MS analysis of various analytes.Keywords:microfluidic chip;mass spectrometry;electrospray ionization;induced polarization
研究领域:
分析化学
·
生物分析
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）