Mass spectrometry最新文献_第8页

Carotenoids: Distribution, Function in Nature, and Analysis Using LC-Photodiode Array Detector (DAD)-MS and MS/MS System. 类胡萝卜素：分布、在自然界中的作用和使用LC光电二极管阵列检测器（DAD）-MS和MS/MS系统的分析。

Mass spectrometry Pub Date : 2023-01-01 Epub Date: 2023-11-01 DOI: 10.5702/massspectrometry.A0133

Takashi Maoka

{"title":"Carotenoids: Distribution, Function in Nature, and Analysis Using LC-Photodiode Array Detector (DAD)-MS and MS/MS System.","authors":"Takashi Maoka","doi":"10.5702/massspectrometry.A0133","DOIUrl":"10.5702/massspectrometry.A0133","url":null,"abstract":"Carotenoids are tetraterpene pigments that are present in photosynthetic bacteria, some species of archaea and fungi, algae, plants, and animals. Carotenoids are essential pigments in photosynthetic organs along with chlorophylls. Carotenoids also act as photo-protectors, antioxidants, color attractants, and precursors of plant hormones in plants. Carotenoids in animals play important roles, such as precursors of vitamin A, photo-protectors, antioxidants, enhancers of immunity, and contributors to reproduction. More than 850 kinds of carotenoids are present in nature. The structures are similar and all of them are labile. Analysis of natural carotenoids requires the establishment of reliable methods for analyzing them. Liquid chromatography-mass spectrometry (LC-MS) and mass spectrometry/mass spectrometry (MS/MS) coupled with photodiode array detector (DAD) is an important tool for analysis of natural carotenoids. Electrospray ionization and atmospheric pressure chemical ionization are commonly used for ionization of LC-MS of carotenoids. MS and MS/MS provide not only molecular weight information but also some structural information on carotenoids. Ultraviolet-visible spectra from DAD provide information on chromophore systems, which cannot be provided by MS spectral data. In the present review, I report the structural diversity and function of natural carotenoids, and also describe the techniques for analysis of natural carotenoids using the LC-DAD-MS and MS/MS system.","PeriodicalId":18243,"journal":{"name":"Mass spectrometry","volume":"12 1","pages":"A0133"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10626154/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71483287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comments on "Identification of Negative Ion at m/z 20 Produced by Atmospheric Pressure Corona Discharge Ionization under Ambient Air". 关于 "常压电晕放电电离在环境空气中产生的 m/z 20 负离子的鉴定 "的评论

Mass spectrometry Pub Date : 2023-01-01 Epub Date: 2023-12-28 DOI: 10.5702/massspectrometry.A0140

Daiki Asakawa, Kenzo Hiraoka

引用次数: 0

Recent Advances and Applications of Ambient Mass Spectrometry Imaging in Cancer Research: An Overview. 环境质谱成像在癌症研究中的最新进展和应用综述。

Mass spectrometry Pub Date : 2023-01-01 Epub Date: 2023-09-28 DOI: 10.5702/massspectrometry.A0129

Bharath S Kumar

{"title":"Recent Advances and Applications of Ambient Mass Spectrometry Imaging in Cancer Research: An Overview.","authors":"Bharath S Kumar","doi":"10.5702/massspectrometry.A0129","DOIUrl":"https://doi.org/10.5702/massspectrometry.A0129","url":null,"abstract":"Cancer metabolic variability has a significant impact on both diagnosis and treatment outcomes. The discovery of novel biological indicators and metabolic dysregulation, can significantly rely on comprehension of the modified metabolism in cancer, is a research focus. Tissue histology is a critical feature in the diagnostic testing of many ailments, such as cancer. To assess the surgical margin of the tumour on patients, frozen section histology is a tedious, laborious, and typically arbitrary method. Concurrent monitoring of ion images in tissues facilitated by the latest advancements in mass spectrometry imaging (MSI) is far more efficient than optical tissue image analysis utilized in conventional histopathology examination. This article focuses on the \"desorption electrospray ionization (DESI)-MSI\" technique's most recent advancements and uses in cancer research. DESI-MSI can provide wealthy information based on the variances in metabolites and lipids in normal and cancerous tissues by acquiring ion images of the lipid and metabolite variances on biopsy samples. As opposed to a systematic review, this article offers a synopsis of the most widely employed cutting-edge DESI-MSI techniques in cancer research.","PeriodicalId":18243,"journal":{"name":"Mass spectrometry","volume":"12 1","pages":"A0129"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/75/d3/massspectrometry-12-1-A0129.PMC10542858.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41139614","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Estimation of the Spatial Extent of the Transient Gain Drop in a Microchannel Plate. 微通道板瞬态增益下降空间范围的估计。

Mass spectrometry Pub Date : 2023-01-01 Epub Date: 2023-11-07 DOI: 10.5702/massspectrometry.A0134

Hiroshi Kobayashi, Toshinobu Hondo, Yasuo Kanematsu, Motohiro Suyama, Michisato Toyoda

{"title":"Estimation of the Spatial Extent of the Transient Gain Drop in a Microchannel Plate.","authors":"Hiroshi Kobayashi, Toshinobu Hondo, Yasuo Kanematsu, Motohiro Suyama, Michisato Toyoda","doi":"10.5702/massspectrometry.A0134","DOIUrl":"10.5702/massspectrometry.A0134","url":null,"abstract":"The gain of the microchannel plate temporally drops after an ion initiates an electron avalanche. Electron multiplication was expected to deplete the charge from the microchannel wall and produce the depleted charge (wall charge). Moreover, it was reported that the gain drop occurred not only in the activated channels, where the electrons are multiplied, but also in the surrounding channels. One mechanism of the gain-drop spatial extension has been considered as that the wall charges in the activated channels change the electric field in the surrounding channels. Anacker et al. assumed that the wall charge is a uniform line charge; the gain-drop spatial extent should be proportional to the amount of the wall charges. We considered that the wall charges exponentially increased in the channel toward the exit. In this study, the electric field produced by the wall charges was calculated, considering the distribution of the wall charges. The transverse electric field generated by the wall charges was expected to disturb the electron trajectory near the channel exit and decrease the number of secondary electrons emitted per collision (gain per collision), resulting in a gain drop. The gain per collision was calculated to decrease by 22% for the position where the gain decreased significantly in the presence of the transverse electric field of 3×105 V/m. In our model, the gain-drop spatial extent extended proportionally to the square root of the wall charges when the distance from the activated channel exceeded 50 μm.","PeriodicalId":18243,"journal":{"name":"Mass spectrometry","volume":"12 1","pages":"A0134"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10632093/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89718843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fragmentation and Ionization Efficiency of Positional and Functional Isomers of Paeoniflorin Derivatives in Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry 基质辅助激光解吸/电离飞行时间质谱分析芍药苷衍生物位置和功能异构体的碎片化和电离效率

Mass spectrometry Pub Date : 2022-02-28 DOI: 10.5702/massspectrometry.A0101

T. Yamagaki, Kohtaro Sugahara, K. Fujikawa, Kazuto Washida

引用次数: 0

Mass Spectrometry Imaging 质谱成像

Mass spectrometry Pub Date : 2022-02-25 DOI: 10.5702/massspectrometry.A0102

S. Shimma

引用次数: 1

Electrospray Ionization Mass Spectrometry of Apolipoprotein CIII to Evaluate O-glycan Site Occupancy and Sialylation in Congenital Disorders of Glycosylation. 利用载脂蛋白 CIII 的电喷雾离子化质谱法评估先天性糖基化紊乱的 O-聚糖位点占用率和 Sialylation。

Mass spectrometry Pub Date : 2022-01-01 Epub Date: 2022-08-10 DOI: 10.5702/massspectrometry.A0104

Yoshinao Wada, Nobuhiko Okamoto

{"title":"Electrospray Ionization Mass Spectrometry of Apolipoprotein CIII to Evaluate O-glycan Site Occupancy and Sialylation in Congenital Disorders of Glycosylation.","authors":"Yoshinao Wada, Nobuhiko Okamoto","doi":"10.5702/massspectrometry.A0104","DOIUrl":"10.5702/massspectrometry.A0104","url":null,"abstract":"Congenital disorders of glycosylation (CDG) are inherited metabolic diseases that affect the synthesis of glycoconjugates. Defects in mucin-type O-glycosylation occur independently or in combination with N-glycosylation disorders, and the profiling of the O-glycans of apolipoprotein CIII (apoCIII) by mass spectrometry (MS) can be used to support a diagnosis. The biomarkers are site occupancy and sialylation levels, which are indicated by the content of non-glycosylated apoCIII0a isoform and by the ratio of monosialylated apoCIII1 to disialylated apoCIII2 isoforms, respectively. In this report, electrospray ionization (ESI) quadrupole MS of apoCIII was used to identify these biomarkers. Among the instrumental parameters, the declustering potential (DP) induced the fragmentation of the O-glycan moiety including the Thr-GalNAc linkage, resulting in an increase in apoCIII0a ions. This incurs the risk of creating a false positive for reduced site occupancy. The apoCIII1/apoCIII2 ratio was substantially unchanged despite some dissociation of sialic acids. Therefore, appropriate DP settings are especially important when transferrin, which requires a higher DP, for N-glycosylation disorders is analyzed simultaneously with apoCIII in a single ESI MS measurement. Finally, a reference range of diagnostic biomarkers and mass spectra of apoCIII obtained from patients with SLC35A1-, TRAPPC11-, and ATP6V0A2-CDG are presented.","PeriodicalId":18243,"journal":{"name":"Mass spectrometry","volume":" ","pages":"A0104"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9396207/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40346745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Electrospray Ionization Mass Spectrometry of Transferrin: Use of Quadrupole Mass Analyzers for Congenital Disorders of Glycosylation. 转铁蛋白的电喷雾电离质谱分析:四极杆质谱分析仪用于先天性糖基化疾病。

Mass spectrometry Pub Date : 2022-01-01 Epub Date: 2022-04-15 DOI: 10.5702/massspectrometry.A0103

Yoshinao Wada, Nobuhiko Okamoto

{"title":"Electrospray Ionization Mass Spectrometry of Transferrin: Use of Quadrupole Mass Analyzers for Congenital Disorders of Glycosylation.","authors":"Yoshinao Wada, Nobuhiko Okamoto","doi":"10.5702/massspectrometry.A0103","DOIUrl":"https://doi.org/10.5702/massspectrometry.A0103","url":null,"abstract":"Electrospray ionization (ESI) mass spectrometry of transferrin can be used to diagnose congenital disorders of glycosylation (CDG) by detecting abnormal N-glycosylation due to reduced site occupancy or processing failure. Time-of-flight mass spectrometers are widely used to separate 25-45 charged ions in the m/z 1,700-3,000 range, and a summed zero-charge mass distribution is generated despite the risk of improper deconvolution. In this study, the low m/z region of the multiply-charged ion mass spectrum enabled a robust analysis of CDG. A triple quadrupole mass spectrometer, the standard instrument for newborn screening for inborn errors of metabolism, permitted the identification of the key ions characteristic of different types of CDG affecting PMM2, ALG14, SLC35A1, SLC35A2, MAN1B1 and PGM1 in the m/z 1,970-2,000 region. Charge deconvolution was used as a complementary tool for validating the findings. It was necessary to set a cutoff level for the evaluation, since small peaks indicating glycosylation failure or reduced sialylation were observed, even in control subjects. This method and workflow facilitates the implementation of MS-based analyses and the screening of CDG in clinical laboratories.","PeriodicalId":18243,"journal":{"name":"Mass spectrometry","volume":" ","pages":"A0103"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9395324/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40346746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Improvement in Ionization Efficiency Using Metal Oxide Nanoparticles in Laser Desorption/Ionization Mass Spectrometry of a Cancer Drug. 金属氧化物纳米粒子在抗癌药物激光解吸/电离质谱分析中提高电离效率。

Mass spectrometry Pub Date : 2021-01-01 Epub Date: 2021-12-23 DOI: 10.5702/massspectrometry.A0099

Hiroki Kannen, Yuto Miyoshi, Hisanao Hazama, Kunio Awazu

{"title":"Improvement in Ionization Efficiency Using Metal Oxide Nanoparticles in Laser Desorption/Ionization Mass Spectrometry of a Cancer Drug.","authors":"Hiroki Kannen, Yuto Miyoshi, Hisanao Hazama, Kunio Awazu","doi":"10.5702/massspectrometry.A0099","DOIUrl":"https://doi.org/10.5702/massspectrometry.A0099","url":null,"abstract":"Mass spectrometry imaging (MSI) without labeling has the potential for faster screening in drug development. Matrix-assisted laser desorption/ionization (MALDI) is typically used, but it has a large matrix size and uneven drug distribution. Surface-assisted laser desorption/ionization (SALDI) using nanoparticles (NPs) may overcome these issues. Here, the influence of NPs, solvent ratio, and order of dropping of NPs on SALDI-MSI of protoporphyrin IX (PpIX), a cancer drug, are reported. A solution of PpIX in a 50% aqueous solution of 50% acetonitrile at a concentration of 10 μM was used. The NPs include ZnO, Fe3O4, and four types of TiO2. The NPs were fabricated by dissolving them on an aqueous 90% acetonitrile solution. Mass spectra were obtained with a time-of-flight mass spectrometer using a Nd:YAG laser at a 355-nm wavelength. The signal intensity using TiO2 at a 0.5 mg/mL concentration in 50% acetonitrile was increased by 1.6-fold compared to that without TiO2. Changing the solvent to 90% acetonitrile gave a uniform TiO2 distribution and a 9-fold increase in the signal intensity for PpIX. Among the four types of TiO2 with different particle sizes and crystal structures, TiO2 with a smaller particle size and a rutile crystal structure produced the highest signal intensity. Forming a layer on top of the PpIX also resulted in an increased signal intensity. Hence, SALDI using TiO2 provides effective ionization of the drug. In the future, we plan to investigate a spray method for the ionization of PpIX using TiO2 for the MSI of various drugs.","PeriodicalId":18243,"journal":{"name":"Mass spectrometry","volume":"10 1","pages":"A0099"},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8697360/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39792149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Gas-Phase Adsorption of N₂ on Protonated Molecules and Its Application to the Structural Elucidation of Small Molecules. 质子化分子对N2的气相吸附及其在小分子结构解析中的应用。

Mass spectrometry Pub Date : 2021-01-01 Epub Date: 2021-06-10 DOI: 10.5702/massspectrometry.A0096

Hiromori Murashima, Akimasa Fujihara

{"title":"Gas-Phase Adsorption of N2 on Protonated Molecules and Its Application to the Structural Elucidation of Small Molecules.","authors":"Hiromori Murashima, Akimasa Fujihara","doi":"10.5702/massspectrometry.A0096","DOIUrl":"https://doi.org/10.5702/massspectrometry.A0096","url":null,"abstract":"The gas-phase adsorption of N2 on protonated serine (Ser, C3H7NO3), threonine (Thr, C4H9NO3), glycine (Gly, C2H5NO2), and 2-aminoethanol (C2H7NO) was investigated using a tandem mass spectrometer equipped with an electrospray ionization source and a cold ion trap. N2 molecules were adsorbed on the free X-H (X=O and N) groups of protonated molecules. Gas-phase N2 adsorption-mass spectrometry detected the presence of free X-H groups in the molecular structures, and was applied to the structural elucidation of small molecules. When the 93 structures with an elemental composition of C3H7NO3 were filtered using the gas-phase N2 adsorption-mass spectrometry results for Ser, the number of possible molecular structures was reduced to 8 via the quantification of the X-H groups. Restricting and minimizing the number of possible candidates were effective steps in the structural elucidation process. Gas-phase N2 adsorption-mass spectrometry combined with mass spectrometry-based techniques has the potential for being useful for elucidating the molecular structures of a variety of molecules.","PeriodicalId":18243,"journal":{"name":"Mass spectrometry","volume":"10 1","pages":"A0096"},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8188007/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39238233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1