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近年来,无需复杂样品前处理、且在开放环境下实现离子化的常压敞开式离子化质谱技术( Ambientionization mass spectrometry,AI - MS)的研制与应用成为质谱学领域的前沿及备受关注的研究方向.该文综述了AI离子源的基本原理、特征与应用进展,并结合笔者研制的空气动力辅助离子化(Air flow assisted ionization,AFAI)技术,介绍了气流辅助常压敞开式离子化技术的基本特点及其应用.展望了常压敞开式离子化技术的发展趋势. 相似文献
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Xiang-Yu GUO Xue-Mei HUANG Jun-Feng ZHAI Hua BAI Xiao-Xu LI Xiao-Xiao MA Qiang MA 《分析化学》2019,47(3):335-346
The development and applications of ambient ionization and miniature mass spectrometry are current research focus in chemical measurement. The analytical technology based on the combination of ambient ionization and miniature mass spectrometry can bypass chromatographic separation and eliminate or simplify sample pretreatment process. The protocol can reverse the labor-intensive and time-consuming drawbacks of traditional analytical methodologies, and realize rapid, on-site analysis with high sensitivity and high throughput. In this paper, the research progress and applications of ambient ionization and miniature mass spectrometry in the fields of food safety, consumer product safety, public security, life sciences and environmental monitoring, are reviewed, and future trends and prospects are discussed, which may provide technical guidance for the researchers engaged in relevant fields. 相似文献
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常压敞开式离子化质谱(Ambient ionization mass spectrometry,AIMS)是指无需复杂样品前处理,并且可在开放环境下对样品进行解吸和离子化的质谱技术。随着该技术的逐渐成熟,其在临床医学诊断中的应用越来越广泛。该文综述了AIMS领域的各种技术在肿瘤组织诊断中的应用,并对未来进行了展望。 相似文献
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Hung Su Zong-Han Jiang Shu-Fen Chiou Jentaie Shiea Deng-Chyang Wu Sung-Pin Tseng Shu-Huei Jain Chung-Yu Chang Po-Liang Lu 《Molecules (Basel, Switzerland)》2022,27(9)
Ambient ionization mass spectrometry (AIMS) is both labor and time saving and has been proven to be useful for the rapid delineation of trace organic and biological compounds with minimal sample pretreatment. Herein, an analytical platform of probe sampling combined with a thermal desorption–electrospray ionization/mass spectrometry (TD-ESI/MS) and multivariate statistical analysis was developed to rapidly differentiate bacterial species based on the differences in their lipid profiles. For comparison, protein fingerprinting was also performed with matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) to distinguish these bacterial species. Ten bacterial species, including five Gram-negative and five Gram-positive bacteria, were cultured, and the lipids in the colonies were characterized with TD-ESI/MS. As sample pretreatment was unnecessary, the analysis of the lipids in a bacterial colony growing on a Petri dish was completed within 1 min. The TD-ESI/MS results were further performed by principal component analysis (PCA) and hierarchical cluster analysis (HCA) to assist the classification of the bacteria, and a low relative standard deviation (5.2%) of the total ion current was obtained from repeated analyses of the lipids in a single bacterial colony. The PCA and HCA results indicated that different bacterial species were successfully distinguished by the differences in their lipid profiles as validated by the differences in their protein profiles recorded from the MALDI-TOF analysis. In addition, real-time monitoring of the changes in the specific lipids of a colony with growth time was also achieved with probe sampling and TD-ESI/MS. The developed analytical platform is promising as a useful diagnostic tool by which to rapidly distinguish bacterial species in clinical practice. 相似文献
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Kirsty McKay Tara L. Salter Andrew Bowfield James L. Walsh Ian S. Gilmore James W. Bradley 《Journal of the American Society for Mass Spectrometry》2014,25(9):1528-1537
Plasma-based desorption/ionization sources are an important ionization technique for ambient surface analysis mass spectrometry. In this paper, we compare and contrast three competing plasma based desorption/ionization sources: a radio-frequency (rf) plasma needle, a dielectric barrier plasma jet, and a low-temperature plasma probe. The ambient composition of the three sources and their effectiveness at analyzing a range of pharmaceuticals and polymers were assessed. Results show that the background mass spectrum of each source was dominated by air species, with the rf needle producing a richer ion spectrum consisting mainly of ionized water clusters. It was also seen that each source produced different ion fragments of the analytes under investigation: this is thought to be due to different substrate heating, different ion transport mechanisms, and different electric field orientations. The rf needle was found to fragment the analytes least and as a result it was able to detect larger polymer ions than the other sources. Figure
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Guć Maria Reszke Edward Cegłowski Michał Schroeder Grzegorz 《Plasma Chemistry and Plasma Processing》2019,39(4):1001-1017
Plasma Chemistry and Plasma Processing - A new direct-current microwave argon plasma source was designed and constructed for use in mass spectrometry. Solid samples and analytes on solid materials... 相似文献
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本研究以721矿和745矿嗜酸性氧化亚铁硫杆菌为研究对象,采用常压化学电离质谱直接分析其代谢产物,分别考察了顶空采样( Headspace sampling)、界面采样( Interface sampling)和中性解吸采样( Neutral desorption sampling)3种进样方式对电离效果的影响。在优化条件下,常压化学电离质谱对微生物纯菌种和混合菌种的代谢产物均具有良好的分析能力,可根据获得的代谢产物指纹谱图结合主成分分析( PCA)方法和聚类分析( CA)方法区分2个放射性强弱不同区域共4类嗜酸性微生物样品,并对主要胺类、酯类等代谢成分进行串联质谱鉴定,为耐辐射微生物的相关研究提供了一种可借鉴的分析方法。 相似文献
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Andrew Ray 《Chromatographia》2015,78(17-18):1223-1224
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Sara E. Kern Lora A. Lin Frederick L. Fricke 《Journal of the American Society for Mass Spectrometry》2014,25(8):1482-1488
U.S. food imports have been increasing steadily for decades, intensifying the need for a rapid and sensitive screening technique. A method has been developed that uses foam disks to sample the surface of incoming produce. This work provides complimentary information to the extensive amount of published pesticide fragmentation data collected using LCMS systems (Sack et al. Journal of Agricultural and Food Chemistry, 59, 6383–6411, 2011; Mol et al. Analytical and Bioanalytical Chemistry, 403, 2891–2908, 2012). The disks are directly analyzed using transmission-mode direct analysis in real time (DART) ambient pressure desorption ionization coupled to a high resolution accurate mass-mass spectrometer (HRAM-MS). In order to provide more certainty in the identification of the pesticides detected, a library of accurate mass fragments and isotopes of the protonated parent molecular ion (the [M+H]+) has been developed. The HRAM-MS is equipped with a quadrupole mass filter, providing the capability of “data-dependent” fragmentation, as opposed to “all -ion” fragmentation (where all of the ions enter a collision chamber and are fragmented at once). A temperature gradient for the DART helium stream and multiple collision energies were employed to detect and fragment 164 pesticides of varying chemical classes, sizes, and polarities. The accurate mass information of precursor ([M+H]+ ion) and fragment ions is essential in correctly identifying chemical contaminants on the surface of imported produce. Additionally, the inclusion of isotopes of the [M+H]+ in the database adds another metric to the confirmation process. The fragmentation data were collected using a Q-Exactive mass spectrometer and were added to a database used to process data collected with an Exactive mass spectrometer, an instrument that is more readily available for this screening application. The commodities investigated range from smooth-skinned produce such as apples to rougher surfaces like broccoli. The minimal sample preparation and absence of chromatography has shortened the analysis time to about 15 min per sample, and the simplicity and robustness of the technique make it ideal for rapid screening. Figure
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Yi Cai Dr. Pengyuan Liu Dr. Michael A. Held Dr. Howard D. Dewald Dr. Hao Chen 《Chemphyschem》2016,17(8):1104-1108
A new coupling of electrochemistry with mass spectrometry (MS) using probe electrospray ionization (PESI) is presented. Due to the high salt tolerance of PESI, the detection of electrochemical reaction products in room‐temperature ionic liquids (RTILs) is realized for the first time. Furthermore, PESI‐MS allows the analysis of electrochemical reaction products on different or multiple electrode surfaces. In addition, peptides and proteins fractionated through isoelectric focusing (IEF) in the presence of an external electric field can also be directly analyzed by using PESI‐MS, suggesting a new and rapid characterization means for the IEF technique. This study reveals the versatility of EC/PESI‐MS, which could have an impact in electrochemistry and bioanalysis fields. 相似文献
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Christian Janfelt Asger W. N?rgaard 《Journal of the American Society for Mass Spectrometry》2012,23(10):1670-1678
Easy ambient sonic spray ionization (EASI) and desorption electrospray ionization (DESI) were used for imaging of a number of samples, including sections of rat brain and imprints of plant material on porous Teflon. A novel approach termed Displaced Dual-mode Imaging was utilized for the direct comparison of the two methods: Images were recorded with the individual rows alternating between EASI and DESI, yielding a separate image for each technique recorded under perfectly similar conditions on the same sample. EASI works reliably for imaging of all samples, but the choice of spray solvent and flow rate is more critical in tissue imaging with EASI than with DESI. The overall sensitivity of EASI is, in general, slightly lower than that of DESI, and the representation of the dynamic range is different in images of the two techniques for some samples. However, for abundant compounds, EASI works well, resulting in images of similar quality as DESI. EASI can thus be used in imaging experiments where the application of high voltage is impractical or undesirable. The present study is in its nature also a comparison of the characteristics of the two techniques, showing results also applicable for non-imaging work, with regards to sensitivity and experimental conditions. 相似文献