Mass spectrometry最新文献

Mass Spectrometry Imaging of Time-Dependently Photodegraded Light Stabilizers in Polyethylene Films Using Tapping-Mode Scanning Probe Electrospray Ionization. 利用轻敲模式扫描探针电喷雾电离质谱成像聚乙烯薄膜中随时间变化的光降解光稳定剂。

Mass spectrometry Pub Date : 2025-01-01 Epub Date: 2025-06-06 DOI: 10.5702/massspectrometry.A0173

Tsuyoshi Akiyama, Yoichi Otsuka, Mengze Sun, Shinichi Yamaguchi, Michisato Toyoda

{"title":"Mass Spectrometry Imaging of Time-Dependently Photodegraded Light Stabilizers in Polyethylene Films Using Tapping-Mode Scanning Probe Electrospray Ionization.","authors":"Tsuyoshi Akiyama, Yoichi Otsuka, Mengze Sun, Shinichi Yamaguchi, Michisato Toyoda","doi":"10.5702/massspectrometry.A0173","DOIUrl":"10.5702/massspectrometry.A0173","url":null,"abstract":"Light stabilizers are additives that are widely used to improve the lifespan and performance of polymer materials. To develop advanced polymer materials, analytical techniques investigate the degradation mechanisms and distribution of additives in polymers are crucial. Herein, two extraction-ionization methods were used: tapping-mode scanning probe electrospray ionization (t-SPESI) and liquid extraction surface analysis (LESA). The distribution and molecular structure of the photodegradation products were investigated using polyethylene films containing two types of oligomeric hindered amine light stabilizers (o-HALS). In addition, to study the relationship between light irradiation time and the relative amount of photodegradation products, we developed a method for preparing films with multiple photodegradation regions. Mass spectrometry imaging (MSI) using t-SPESI (t-SPESI-MSI) revealed that the signal intensities of HALS decreased with the time of light irradiation, and its degradation products progressively changed. Moreover, tandem mass spectrometry (MS/MS) using LESA (LESA-MS/MS) revealed that degradation products were generated by HALS fragmentation in the polymer film. By integrating these results, we propose multiple and stepwise reactions for the formation of the photodegradation products. Results indicate that the combined use of t-SPESI-MSI and LESA-MS/MS can directly analyze and understand the photodegradation mechanism of o-HALS in polymer materials.","PeriodicalId":18243,"journal":{"name":"Mass spectrometry","volume":"14 1","pages":"A0173"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12146835/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144258323","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

Erratum: Mass Spectrometry as a First-Line Diagnostic Aid for Congenital Disorders of Glycosylation. 勘误：质谱法作为先天性糖基化疾病的一线诊断援助。

Mass spectrometry Pub Date : 2025-01-01 Epub Date: 2025-03-04 DOI: 10.5702/massspectrometry.X0002

Yoshinao Wada

引用次数: 0

Mass Spectrometry as a First-Line Diagnostic Aid for Congenital Disorders of Glycosylation. 质谱法作为先天性糖基化疾病的一线诊断辅助。

Mass spectrometry Pub Date : 2025-01-01 Epub Date: 2025-02-08 DOI: 10.5702/massspectrometry.A0169

Yoshinao Wada

{"title":"Mass Spectrometry as a First-Line Diagnostic Aid for Congenital Disorders of Glycosylation.","authors":"Yoshinao Wada","doi":"10.5702/massspectrometry.A0169","DOIUrl":"10.5702/massspectrometry.A0169","url":null,"abstract":"Congenital disorders of glycosylation (CDG) constitute a group of rare inherited metabolic disorders resulting from mutations in genes involved in the biosynthesis of glycan chains that are covalently attached to proteins or lipids. To date, nearly 200 genes have been identified as responsible for these disorders, with approximately half implicated in N-glycosylation defects. Diagnosis of CDG is primarily achieved through genetic analysis and the identification of glycan abnormalities, referred to as molecular phenotypes. With the increasing use of whole exome and genome sequencing in the investigation of diseases with unknown etiology, the number of cases suspected of CDG is increasing, highlighting the necessity for glycan analysis. Molecular phenotyping in CDG typically targets glycoproteins, with transferrin and apolipoprotein CIII being key representatives of N- and mucin-type O-glycosylation, respectively. Mass spectrometry (MS) provides rapid analysis and yields moderately detailed information, establishing it as a first-line molecular diagnostic tool that complements genetic analysis. Structural anomalies detected by MS can be classified into distinct patterns, which may indicate specific defects within the glycosylation pathway. In cases of CDG types that lack clear molecular phenotypes, characteristic metabolites can often be identified and quantified by MS, further aiding in the diagnostic process. Molecular diagnosis of CDG using MS can be performed with a standard mass spectrometer and a dried blood spot on filter paper, enabling its application in population-based mass screening.","PeriodicalId":18243,"journal":{"name":"Mass spectrometry","volume":"14 1","pages":"A0169"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11808201/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143391379","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

An Effective Approach to Mass Spectrometry Imaging Data Partitioning Using UMAP and k-Means Clustering. 基于UMAP和k-Means聚类的质谱成像数据分割方法

Mass spectrometry Pub Date : 2025-01-01 Epub Date: 2025-05-28 DOI: 10.5702/massspectrometry.A0174

Shinichi Yamaguchi, Masaya Ikegawa

{"title":"An Effective Approach to Mass Spectrometry Imaging Data Partitioning Using UMAP and k-Means Clustering.","authors":"Shinichi Yamaguchi, Masaya Ikegawa","doi":"10.5702/massspectrometry.A0174","DOIUrl":"10.5702/massspectrometry.A0174","url":null,"abstract":"In this study, we propose an effective summarization method for mass spectrometry imaging (MSI) data and demonstrate its efficacy. The MSI data used in this study were obtained from thoracic tissue sections of mice, including the thymus. The thymus is a multi-lobed organ composed of cortical and medullary areas, playing a crucial role in T-cell differentiation. By applying MSI to the thoracic region, including the thymus, this study aims to comprehensively visualize changes in molecular localization and metabolic patterns across thoracic organs. MSI data are highly information-rich, making effective summarization and organization challenging. Therefore, we explored a method to organize and visualize the data based on either spatial or m/z values. Specifically, we employed Uniform Manifold Approximation and Projection (UMAP) to project m/z data into 3-dimensional space, followed by k-means clustering to divide it into multiple clusters. This approach enables detailed and comprehensive representation of diverse features. The objective of this study is to identify molecular localizations and patterns that conventional methods may overlook. Furthermore, experimental results demonstrated that the pseudo-color images generated using UMAP highlighted specific m/z values that significantly influence image characteristics. When focusing on thoracic data, spatial segmentation resulted in clearer color differentiation; however, molecular localizations corresponding to blood vessels were not observed. This finding confirms that m/z segmentation is more effective than spatial segmentation in discovering new molecular localizations.","PeriodicalId":18243,"journal":{"name":"Mass spectrometry","volume":"14 1","pages":"A0174"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12130678/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144216271","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

Erratum: Development of a Mass Spectrometry Imaging Method to Evaluate the Penetration of Moisturizing Components Coated on Surgical Gloves into Artificial Membranes. 勘误：开发一种质谱成像方法来评估涂在外科手套上的保湿成分对人工膜的渗透。

Mass spectrometry Pub Date : 2025-01-01 Epub Date: 2025-03-27 DOI: 10.5702/massspectrometry.X0003

Erika Nagano, Kazuki Odake, Toru Akiyoshi, Shuichi Shimma

引用次数: 0

Formation of [M-H]⁺ of 4-Substituted-1-(methoxymethyl)benzene Derivatives under Positive Fast Atom Bombardment Ionization. 正快速原子弹轰击电离下 4-取代-1-（甲氧基甲基）苯衍生物 [M-H]+ 的形成。

Mass spectrometry Pub Date : 2025-01-01 Epub Date: 2025-03-13 DOI: 10.5702/massspectrometry.A0171

Shizuyo Horiyama, Motohiro Shizuma

{"title":"Formation of [M-H]+ of 4-Substituted-1-(methoxymethyl)benzene Derivatives under Positive Fast Atom Bombardment Ionization.","authors":"Shizuyo Horiyama, Motohiro Shizuma","doi":"10.5702/massspectrometry.A0171","DOIUrl":"10.5702/massspectrometry.A0171","url":null,"abstract":"The appearance of the characteristic peak of the hydride-eliminated molecule [M-H]+ under a positive ion mode (positive) fast atom bombardment (FAB) ionization condition and liquid-assisted secondary ion mass spectrometry (LSIMS) conditions is known for some compounds and the mechanism of its formation has been investigated. In this study, we investigated the formation mechanism of the hydride-eliminated molecule [M-H]+ from 4-substituted-1-(methoxymethyl)benzene under a positive FAB ionization condition. The mass spectra of 4-methoxy-1-(methoxymethyl)benzene (1), 4-methoxy-1-(methoxymethyl-d 2-)benzene (1-d 2), and 4-methoxy-1-(methoxymethyl-d 3)benzene (1-d 3) were measured under the positive FAB conditions. [M-H]+ was observed for 1 and 1-d 3, and [M-D]+ for 1-d 2, indicating that the site of hydride elimination was the methylene of the 1-(methoxymethyl) moiety. Since [M-H]+ was hardly observed under the conditions of positive electron ionization and positive chemical ionization in the gas phase, the hydride elimination is a reaction specific to positive FAB ionization. To examine the contribution of the 4-substituent to the hydride elimination reaction, the mass spectra of (methoxymethyl)benzene (2) and 4-nitro-1-(methoxymethyl)benzene (3) were measured using the positive FAB. The ordering of the relative peak intensity of [M-H]+ for [M+H]+ in the FAB mass spectra was 1 > 2 > 3, and the results suggest that the electron-donating power of the substituents is an important factor in the formation of [M-H]+.","PeriodicalId":18243,"journal":{"name":"Mass spectrometry","volume":"14 1","pages":"A0171"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11911718/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143649734","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

Alkylated Hydroxychalcone: A Novel Matrix for Peptide Analysis by Matrix-Assisted Laser Desorption Ionization Mass Spectrometry. 烷基化羟基查尔酮：一种新型基质辅助激光解吸电离质谱分析多肽的基质。

Mass spectrometry Pub Date : 2025-01-01 Epub Date: 2025-03-18 DOI: 10.5702/massspectrometry.A0170

Manaho Yamaguchi, Yuko Fukuyama, Shunsuke Izumi

引用次数: 0

Stir Bar Sorptive Extraction (SBSE)-HPLC-Tandem MS-Based Method for Multi-Residue Determination of Pesticides in Drinking Water. 搅拌棒吸附萃取-高效液相色谱-串联质谱法测定饮用水中农药多残留。

Mass spectrometry Pub Date : 2025-01-01 Epub Date: 2025-03-29 DOI: 10.5702/massspectrometry.A0172

Alex Affricano, Silvia Serra, Alice Di Bernardo, Riccardo Aigotti, Francesco Floris, Federica Dal Bello, Claudio Medana

{"title":"Stir Bar Sorptive Extraction (SBSE)-HPLC-Tandem MS-Based Method for Multi-Residue Determination of Pesticides in Drinking Water.","authors":"Alex Affricano, Silvia Serra, Alice Di Bernardo, Riccardo Aigotti, Francesco Floris, Federica Dal Bello, Claudio Medana","doi":"10.5702/massspectrometry.A0172","DOIUrl":"10.5702/massspectrometry.A0172","url":null,"abstract":"Pesticide residues in water contamination represent a significant public and political issue due to their harmful effects on the environment, biodiversity, and human health, even at low concentrations. Pesticides are chemically heterogeneous, covering a wide range of LogK o/w values. Therefore, developing sensitive methods to detect a broad spectrum of hazardous chemicals in aqueous matrices is challenging. Gas and liquid chromatography/high-performance liquid chromatography-mass spectrometry (GC/HPLC-MS) are established tools but typically require pre-concentration steps. Stir bar sorptive extraction (SBSE) is a green, simple, automatable, and HPLC-compatible technique. This study presents a multi-residue method for determining 131 pesticides in mineral water using SBSE followed by HPLC-tandem MS. The selected pesticides, from various chemical classes, were evaluated in fortified ultra-pure and mineral water samples. The method demonstrated excellent sensitivity, with lower limits of quantification ranging from 20 to 50 ng/L for all analytes, enabling detection at trace levels. Selectivity was high (SEL% <20%), and reproducibility was confirmed with RSD% values below 20%. Intra- and interday precision tests revealed RSD% values from 0.23% to 19.81%. Trueness was validated with BIAS% below 20% at all concentrations. Uncertainty values were acceptable, with U% ranging from 1.44% to 49.24%. This SBSE-HPLC-tandem MS method is a robust, efficient, and reliable alternative to traditional approaches for routine monitoring of pesticide residues in drinking water, with quantification limits below regulatory requirements. It offers a suitable tool for public health applications, ensuring reliable pesticide detection in complex water matrices.","PeriodicalId":18243,"journal":{"name":"Mass spectrometry","volume":"14 1","pages":"A0172"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11955823/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143753437","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

Characterization of Ultraviolet-Degraded Polyethylene Terephthalate Film Using a Complementary Approach: Reactive Pyrolysis-Gas Chromatography-Mass Spectrometry and Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry. 紫外降解聚对苯二甲酸乙二醇酯薄膜的互补表征：反应热解-气相色谱-质谱和基质辅助激光解吸/电离质谱。

Mass spectrometry Pub Date : 2025-01-01 Epub Date: 2025-01-15 DOI: 10.5702/massspectrometry.A0168

Azusa Kubota, Takaya Satoh, Masaaki Ubukata, Ayumi Kubo, Chikako Nakayama

{"title":"Characterization of Ultraviolet-Degraded Polyethylene Terephthalate Film Using a Complementary Approach: Reactive Pyrolysis-Gas Chromatography-Mass Spectrometry and Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry.","authors":"Azusa Kubota, Takaya Satoh, Masaaki Ubukata, Ayumi Kubo, Chikako Nakayama","doi":"10.5702/massspectrometry.A0168","DOIUrl":"10.5702/massspectrometry.A0168","url":null,"abstract":"Polyethylene terephthalate (PET) is widely used across various industries owing to its versatility and favorable properties, including application in beverage bottles, food containers, textile fibers, engineering resins, films, and sheets. However, polymer materials are susceptible to degradation from factors such as light, oxygen, and heat. Therefore, it is crucial to understand the structural changes that occur during degradation and the extent of these changes. This report investigates the structural alterations in PET films resulting from ultraviolet (UV) irradiation utilizing pyrolysis-gas chromatography time-of-flight mass spectrometry (Py-GC-TOFMS) and matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOFMS). Using the reactive Py-GC-TOFMS, we estimated the composition of the pyrolysis products resulting from UV degradation through electron ionization, soft ionization, and exact mass measurements. Additionally, artificial intelligence (AI)-based structure analysis was performed to evaluate these compounds' structures. Notably, most degradation products were not found in the National Institute of Standards and Technology database, underscoring the effectiveness of our approach. Using MALDI-TOFMS analysis, we determine the changes in the end groups before and after UV irradiation. This analysis confirmed the generation of a series of carboxylic acid end groups as a result of degradation, a polymer series not detected by reactive pyrolysis GC-MS. We also explored degradation in the depth direction, demonstrating that degradation progresses gradually to depths of several micrometers. Our findings highlight the importance of employing mass spectrometry techniques for a comprehensive analysis of polymer degradation.","PeriodicalId":18243,"journal":{"name":"Mass spectrometry","volume":"14 1","pages":"A0168"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11744444/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007999","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

Quantum Chemical Analysis of the Molecular and Fragment Ion Formation of Butyrophenone by High-Electric Field Tunnel Ionization at Atmospheric Pressure. 大气压下通过高电场隧道电离形成丁酮分子和碎片离子的量子化学分析。

Mass spectrometry Pub Date : 2024-01-01 Epub Date: 2024-10-25 DOI: 10.5702/massspectrometry.A0156

Mitsuo Takayama

{"title":"Quantum Chemical Analysis of the Molecular and Fragment Ion Formation of Butyrophenone by High-Electric Field Tunnel Ionization at Atmospheric Pressure.","authors":"Mitsuo Takayama","doi":"10.5702/massspectrometry.A0156","DOIUrl":"10.5702/massspectrometry.A0156","url":null,"abstract":"The molecular ion M+· was observed when the liquid sample of butyrophenone was supplied using atmospheric pressure corona discharge (APCD). In contrast, the vapor supply resulted in the formation of the protonated molecule [M+H]+. The mass spectrum obtained with the liquid supply showed two distinctive fragment ions at m/z 105 and 120, resulting from α-cleavage and McLafferty rearrangement (McLR), respectively. The APCD spectrum showed peaks of M+· and the characteristic two fragment ions that were the same as the field ionization mass spectra of butyrophenone as reported by Chait et al. and Beckey et al. The formation of the molecular and fragment ions strongly indicated that high-electric field tunnel ionization (HEFTI) occurs by the HEF strength exceeding 108 V/m at the tip of the corona needle in APCD. The charge and spin density distributions of the molecular and fragment ions were analyzed by quantum chemical calculations using time-dependent density functional theory (TDDFT) and natural bond orbital (NBO) analysis.","PeriodicalId":18243,"journal":{"name":"Mass spectrometry","volume":"13 1","pages":"A0156"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11522704/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142546294","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