International Journal of Mass Spectrometry最新文献_第3页

Identification of aromatic aldehyde and keto functionalities in protonated polyfunctional analytes via gas-phase ion-molecule reactions followed by collision-activated dissociation in a linear quadrupole ion trap mass spectrometer 在线性四极离子阱质谱仪中通过气相离子分子反应和碰撞激活解离鉴定质子化多功能化分析物中的芳香醛和酮类官能团

IF 1.7 3区化学 Q3 PHYSICS, ATOMIC, MOLECULAR & CHEMICAL

International Journal of Mass Spectrometry

Pub Date : 2025-10-31 DOI: 10.1016/j.ijms.2025.117546

Jaskiran Kaur , Ruth O. Anyaeche , Landon Wence , Yue Fu , Kawthar Z. Alzarieni , Hilkka Kenttämaa

The levels of potentially mutagenic impurities and metabolites, such as aldehydes and ketones, are highly regulated in active pharmaceutical ingredients and must be below a critical safety threshold. Therefore, the ability to detect and identify previously known as well as unknown aldehydes and ketones in drug products is of utmost importance. However, traditional tandem mass spectrometry methods based on collision-activated dissociation (CAD) usually fail in this task as isomeric protonated analytes often fragment in an identical manner, and CAD can cause isomerization of the ions. In this study, selective gas-phase ion-molecule reactions of trimethoxymethylsilane (TMMS) with protonated oxygen-containing analytes were combined with diagnostic CAD to reliably detect all mono- and polyfunctional analytes with aromatic aldehyde and ketone functionalities in a mixture. Various aliphatic and aromatic oxygen-containing analytes, e.g., aldehydes, ketones, carboxylic acids, esters, alcohols, phenols, and amides, were protonated in a linear quadrupole ion trap mass spectrometer, transferred from the ion source into the ion trap, isolated, and allowed to react with TMMS. All protonated analytes produced a stable TMMS adduct and/or an adduct that had lost a methanol molecule. CAD of the latter product ion produced diagnostic fragment ions that correspond to the elimination of a formaldehyde molecule, an ion formally corresponding to the elimination of an oxygen atom from the original protonated analyte, and an ion with mass-to-charge ratio one unit less than the MW of the protonated analyte. These three fragment ions are diagnostic for protonated mono- and polyfunctional analytes with aromatic aldehyde and ketone functionalities, with the exception of pyrrole-2-carboxaldehyde and 2-quinolinecarboxaldehyde. Quantum chemical calculations were employed to delineate the likely mechanisms for the formation of the relevant product ions upon ion-molecule reactions and for the diagnostic fragmentation of specific product ions. This analysis does not require model compounds as the ion-molecule reactions are highly predictable, as opposed to CAD reactions.

潜在的致突变杂质和代谢物，如醛类和酮类，在活性药物成分中受到高度管制，必须低于临界安全阈值。因此，检测和鉴定药品中已知和未知的醛类和酮类的能力至关重要。然而，传统的基于碰撞激活解离（CAD）的串联质谱方法通常无法完成这项任务，因为同分异构体质子化分析物通常以相同的方式分裂，并且CAD会导致离子异构化。本研究将三甲氧基甲基硅烷（TMMS）与质子化含氧分析物的选择性气相离子-分子反应与诊断CAD相结合，以可靠地检测混合物中具有芳香醛和酮功能的所有单功能和多功能分析物。各种脂肪族和芳香族含氧分析物，如醛类、酮类、羧酸类、酯类、醇类、酚类和酰胺类，在线性四极离子阱质谱仪中质子化，从离子源转移到离子阱，分离，并允许与TMMS反应。所有质子化分析物都产生稳定的TMMS加合物和/或失去甲醇分子的加合物。后一产物离子的CAD产生的诊断片段离子对应于甲醛分子的消除，一个离子形式上对应于原始质子化分析物中氧原子的消除，一个离子的质量电荷比比质子化分析物的MW小一个单位。除了吡咯-2-甲醛和2-喹啉甲醛外，这三个片段离子可用于诊断具有芳香醛和酮功能的质子化单功能和多功能分析物。采用量子化学计算来描述离子-分子反应中相关产物离子形成的可能机制以及特定产物离子的诊断碎裂。这种分析不需要模型化合物，因为与CAD反应相反，离子-分子反应是高度可预测的。

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引用次数: 0

Proton affinity, pKa, and collision cross section of neonicotinoid pesticides: A DFT approach 新烟碱类农药的质子亲和、pKa和碰撞截面：一个DFT方法

IF 1.7 3区化学 Q3 PHYSICS, ATOMIC, MOLECULAR & CHEMICAL

International Journal of Mass Spectrometry

Pub Date : 2025-10-30 DOI: 10.1016/j.ijms.2025.117547

Younes Valadbeigi

This study presents a comprehensive computational investigation of protonation behavior, proton affinity (PA), pK_a values, and collision cross sections (CCS) for fifteen neonicotinoid pesticides using density functional theory with B3LYP, ωB97X-D, and M06-2X functionals. Protonation sites were systematically evaluated in both gas and aqueous phases. CCS values of the resulting protonated species were computed via the trajectory method using MOBCAL-MPI, showing excellent agreement with experimental data and enabling site-specific protonation prediction. All neonicotinoids except nithiazine had PA values above 900 kJ mol⁻¹, confirming strong gas-phase basicity. Predicted pK_a values of the conjugate acids of neonicotinoids were consistently below 7, indicating low aqueous-phase basicity of the neonicotinoids.

本文采用具有B3LYP、ωB97X-D和M06-2X官能团的密度泛函理论，对15种新烟碱类农药的质子化行为、质子亲和（PA）、pKa值和碰撞截面（CCS）进行了全面的计算研究。在气相和水相中系统地评价了质子化位点。利用MOBCAL-MPI通过轨迹法计算得到的质子化物种的CCS值，结果与实验数据非常吻合，并实现了位点特异性质子化预测。除硝嗪外，所有新烟碱类的PA值均在900 kJ mol−1以上，证实了较强的气相碱性。新烟碱类化合物共轭酸的预测pKa值始终小于7，表明新烟碱类化合物的水相碱度较低。

引用次数: 0

Generation of endohedral metallofullerene ions of Ca1-4C2n+ (44 ≤ 2n ≤ 132) by laser ablation of natural graphite sheets without pretreatment 未经预处理的天然石墨片激光烧蚀生成Ca1-4C2n+(44≤2n≤132)的内质金属富勒烯离子

IF 1.7 3区化学 Q3 PHYSICS, ATOMIC, MOLECULAR & CHEMICAL

International Journal of Mass Spectrometry

Pub Date : 2025-10-24 DOI: 10.1016/j.ijms.2025.117545

Jinyang Li , Shuqi Li , Yongliang Cui , Sen Zhang , Guanxin Yao , Xianyi Zhang , Xianglei Kong

The selection of precursor is essential for the generation of various endohedral metallofullerenes (EMFs) in the laser ablation mass spectrometry experiments. Herein, natural graphite sheets without any pretreatment were applied in the laser ablation experiments with a Fourier transform ion cyclotron resonance (FT ICR) mass spectrometer. EMF ions of

{{Ca}_{1 - 4} @ C}_{2 n}^{+} (44 \leq 2 n \leq 132)

were identified in the mass spectrum. Although the distributions of the mono- and di- EMF ions are somewhat similar to those previously observed with the precursor of graphene/CaCl₂, the tri-EMF ions of

{Ca}_{3} @ C_{2 n}^{+}

(2n = 92–132) and tetra-EMF ions of

{Ca}_{4} @ C_{2 n}^{+}

(2n = 110–124) were also observed, which have not been reported before. The presence of these Ca-related impurities not only indicates that laser ablation mass spectrometry can be an effective means of identifying natural graphite but also suggests that well-designed doping can provide a long-lasting and enduring pathway for the generation of new EMFs.

在激光烧蚀质谱实验中，前驱体的选择是制备各种金属富勒烯（EMFs）的关键。本文采用傅立叶变换离子回旋共振（FT ICR）质谱仪对未经预处理的天然石墨薄片进行激光烧蚀实验。在质谱中鉴定出Ca1−4@C2n+(44≤2n≤132)的EMF离子。虽然单EMF离子和双EMF离子的分布与之前在石墨烯/CaCl2前体中观察到的分布有些相似，但也观察到Ca3@C2n+ (2n = 92-132)的三EMF离子和Ca4@C2n+ (2n = 110-124)的四EMF离子，这在以前没有报道过。这些ca相关杂质的存在不仅表明激光烧蚀质谱法可以成为鉴定天然石墨的有效手段，而且表明精心设计的掺杂可以为新emf的产生提供持久和持久的途径。

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引用次数: 0

Infrared multiple photon dissociation spectroscopy of TaO(OH)2+ and Ta(OH)4+ cations TaO(OH)2+和Ta(OH)4+阳离子的红外多光子解离光谱

IF 1.7 3区化学 Q3 PHYSICS, ATOMIC, MOLECULAR & CHEMICAL

International Journal of Mass Spectrometry

Pub Date : 2025-10-14 DOI: 10.1016/j.ijms.2025.117543

Sarah J. Madlener , Bowei Yuan , Marc Reimann , Shaodong Zhou , Martin K. Beyer , Joost M. Bakker , Christian van der Linde

Transition metal oxides are promising candidates for water activation, a key step in hydrogen production, as they have shown their potential as catalysts. In this study, we present tag-free infrared multiple photon dissociation (IRMPD) spectra of formally singly and doubly hydrated TaO₂⁺ cations in the 350–1650 cm⁻¹ range, measured using the free-electron laser for intracavity experiments (FELICE). In combination with vibrational spectra obtained by quantum chemical calculations, the experimental spectra reveal that the hydroxide species TaO(OH)₂⁺ and Ta(OH)₄⁺ are the dominant species in the experiment. These two structures are also the lowest lying isomers, about 130 kJ mol⁻¹ lower than the energetically closest isomers. The calculated potential energy surfaces and transition states align with earlier studies, confirming the formation of these hydroxide complexes via sequential proton transfers upon complexation of TaO₂⁺ with one and two water molecules, respectively. This work presents the first tag free spectra of these complexes, complementing the spectroscopic picture especially in the low wavenumber region.

过渡金属氧化物是水活化的有希望的候选者，这是制氢的关键步骤，因为它们已经显示出作为催化剂的潜力。在这项研究中，我们使用自由电子激光器进行腔内实验（FELICE），在350-1650 cm−1范围内测量了TaO2+阳离子的形式单水合和双水合的红外多光子解离（IRMPD）光谱。结合量子化学计算得到的振动光谱，实验光谱显示，实验中主要以氢氧根形态的TaO(OH)2+和Ta(OH)4+为主。这两种结构也是能量最低的同分异构体，比能量最接近的同分异构体低约130 kJ mol−1。计算的势能表面和过渡态与早期的研究一致，证实了这些氢氧根配合物的形成是通过TaO2+分别与一个和两个水分子络合后的顺序质子转移。这项工作提出了这些复合物的第一个无标签光谱，补充了光谱图，特别是在低波数区域。

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引用次数: 0

Editorial- Curt Brunnee memorial issue 社论-柯特·布鲁尼纪念特刊

IF 1.7 3区化学 Q3 PHYSICS, ATOMIC, MOLECULAR & CHEMICAL

International Journal of Mass Spectrometry

Pub Date : 2025-10-14 DOI: 10.1016/j.ijms.2025.117544

Alexander A. Makarov

引用次数: 0

Influence of acceleration field and inlet temperature on ion yields of small molecules in atmospheric pressure MALDI 常压下加速场和入口温度对小分子离子产率的影响

IF 1.7 3区化学 Q3 PHYSICS, ATOMIC, MOLECULAR & CHEMICAL

International Journal of Mass Spectrometry

Pub Date : 2025-10-07 DOI: 10.1016/j.ijms.2025.117535

Eugene Moskovets

The optimization of the accelerating electric field near a target plate as well as temperature of the inlet capillary in a mass spectrometer is essential for achieving a high ion yield in atmospheric pressure matrix-assisted laser desorption ionization (AP/MALDI) and atmospheric pressure/laser desorption ionization (AP/LDI). The yields of protonated rhodamine 6G ions, protonated matrix ions (M + H)⁺, matrix radical ions (M•)⁺, as well as protonated reserpine ions were studied as a function of the inlet capillary temperature in Orbitrap and electric field applied across the inlet and MALDI target plate. The findings indicated that 2,5-dihydroxybenzoic acid (DHB) generated predominantly cation radicals (M•)⁺ rather than protonated ions. This trend is not common for most MALDI matrices used for positive-mode MALDI-MS analysis. By changing capillary temperature, it has been found that the temperature trends observed for the (DHB + H)⁺/(DHB•)⁺ ratios in both AP/MALDI and electrospray ionization (ESI) are similar. The ion yield dependence on the electric field strength in AP/MALDI as well as low-pressure MALDI sources proved to be more complex than that suggested in the previously developed model accounting for charge neutralization in the plume mitigated by the field-driven separation of opposite charges. The laser photoionization of the matrix molecules within a thin surface layer of a matrix microcrystal followed by thermally activated proton transfer from the matrix radical cation to adjacent matrix molecules has been discussed.

在常压基质辅助激光解吸电离（AP/MALDI）和常压/激光解吸电离（AP/LDI）中，优化靶板附近的加速电场和质谱仪入口毛细管温度是实现高离子产率的关键。研究了质子化罗丹明6G离子、质子化基质离子(M + H)+、基质自由基离子（M•）+和质子化利血平离子的产率与Orbitrap入口毛细管温度、入口和MALDI靶板上施加电场的关系。结果表明，2,5-二羟基苯甲酸（DHB）主要产生阳离子自由基（M•）+，而不是质子化离子。这种趋势在用于正模式MALDI- ms分析的大多数MALDI矩阵中并不常见。通过改变毛细管温度，发现AP/MALDI和电喷雾电离（ESI）中(DHB + H)+/（DHB•）+比值的温度变化趋势是相似的。在AP/MALDI以及低压MALDI源中，离子产额对电场强度的依赖性比先前开发的模型更为复杂，该模型考虑了电场驱动的相反电荷分离减轻了羽流中的电荷中和作用。本文讨论了基体微晶薄表面层中基体分子的激光光离，随后热激活质子从基体自由基阳离子转移到邻近的基体分子。

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引用次数: 0

Single amino acid variation identification in high resolution tandem mass spectrometry data in bottom up proteomics 自底向上蛋白质组学中单氨基酸变异的高分辨率串联质谱鉴定

IF 1.7 3区化学 Q3 PHYSICS, ATOMIC, MOLECULAR & CHEMICAL

International Journal of Mass Spectrometry

Pub Date : 2025-10-01 DOI: 10.1016/j.ijms.2025.117532

Kishankumar Bhimani , Arina Peresadina , Karina Burmak , Kartik Joshi , Attila Kertesz-Farkas

Database-searching based precursor ion identification in tandem mass spectrometry data analysis is limited to the search space. Once a single amino acid variation (SAAV) or a modification is not included to the search space, then its observed spectra will not be annotated correctly. Several methods have been developed to identify and localize post-translational modifications (PTMs); however, few methods have been introduced to identify peptide sequences with amino acid mutations. Here, we present our approach to detect SAAVs, called SeVa (standing for Sequence Variation). SeVa is based on the High-Resolution Exact P-Value (HR-XPV) method (doi:10.1002/pmic.202300145), which builds an exact empirical null distribution by implicitly scoring the spectra against all possible amino acid sequences in high-resolution fragmentation settings. SeVa extracts the amino acid sequence from HR-XPV, which produces the highest score. The SeVa peptides identified are subjected to a homology search against a proteome database containing shuffled decoy protein sequences. This step increases the sensitivity of the results and the decoy identifications can be used to estimate the FDR. We tested SeVa with two experimental datasets related to immunopeptidomics (PXD017407) and cancer (PDC000224), and our method identified 781 and 15,764 peptide sequences with mutations at 1.68% and 0.52% of FDRs.

串联质谱数据分析中基于数据库搜索的前体离子鉴定受限于搜索空间。一旦单个氨基酸变异（SAAV）或修饰不包含在搜索空间中，则其观测光谱将无法正确注释。已经开发了几种方法来识别和定位翻译后修饰（PTMs）；然而，很少有方法被引入来鉴定氨基酸突变的肽序列。在这里，我们提出了一种检测saav的方法，称为SeVa（代表序列变异）。SeVa基于高分辨率精确p值（HR-XPV）方法（doi:10.1002/pmic）。202300145)，该方法通过对高分辨率片段设置中所有可能的氨基酸序列进行隐式评分，建立了精确的经验零分布。SeVa从HR-XPV中提取的氨基酸序列得分最高。鉴定出的SeVa肽对包含洗牌诱饵蛋白序列的蛋白质组数据库进行同源性搜索。这一步骤提高了结果的灵敏度，并且可以使用诱饵识别来估计FDR。我们使用两个与免疫肽组学（PXD017407）和癌症（PDC000224）相关的实验数据集对SeVa进行了测试，我们的方法鉴定出781和15764个肽序列，突变率分别为1.68%和0.52%。

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引用次数: 0

Methods for a comprehensive targeted and suspect screen survey of exogenous chemicals in shed baby teeth 方法：对脱落乳牙外源性化学物质进行全面、有针对性和可疑的筛查调查

IF 1.7 3区化学 Q3 PHYSICS, ATOMIC, MOLECULAR & CHEMICAL

International Journal of Mass Spectrometry

Pub Date : 2025-09-27 DOI: 10.1016/j.ijms.2025.117534

Lynne P. Heilbrun , Anabel Rodriguez , L. Aubree Shay , David Gimeno Ruiz de Porras , Inkyu Han , Kristin Favela

Background

Semi-volatile organic chemicals (SVOCs) have been studied in shed baby teeth as a potential tool to identify environmental triggers of autism. However, these targeted studies are limited by the availability of standards, leaving a vast number of chemicals unexplored for autism risk.

Objective

We explored the use of two-dimensional gas chromatography time-of-flight mass spectrometry (GCxGC-TOFMS) as a viable and accurate method for identifying and quantifying a wide range of low-level SVOCs in deciduous teeth.

Methods

Tooth samples were derived from The Autism Tooth Fairy Study. Ground tooth samples (n = 44) were analyzed using GCxGC-TOFMS. Targeted and non-targeted analyses were performed. Targeted compounds were reviewed against reference spectra for identification, and non-targets were manually curated using the National Institute of Standards and Technology Library data, as available. Kovat's retention index was used for identifications without a reference standard.

Results

From the 44 tooth samples analyzed, 11,971 total endogenous and exogenous features were cataloged, including unknowns without a suitable library match. Of the 203 compounds detected, 106 high-fidelity matched compounds were identified spanning 45 subclasses of toxicants. Eighty-nine of these compounds are known developmental toxicants or endocrine disruptors. The remaining compounds were toxicants with acute or chronic toxicity data but had no developmental or endocrine-disrupting activity data.

Conclusion

This study demonstrates the utility of GCxGC-TOFMS for detecting a wide range of SVOCs in children's teeth, identifying a substantial number of developmental toxicants and other toxic chemicals. The detection of these compounds highlights critical gaps in our understanding of children's chemical exposures.

半挥发性有机化学物质（SVOCs）已经在脱落的乳牙中进行了研究，作为识别自闭症环境触发因素的潜在工具。然而，这些有针对性的研究受到标准可用性的限制，导致大量的化学物质未被用于自闭症风险的研究。目的探讨二维气相色谱-飞行时间质谱法（GCxGC-TOFMS）作为鉴定和定量乳牙中多种低水平SVOCs的一种可行、准确的方法。方法牙齿样本来源于自闭症牙仙研究。采用GCxGC-TOFMS分析磨牙样品（n = 44）。进行针对性和非针对性分析。根据参考光谱对目标化合物进行鉴定，非目标化合物使用美国国家标准与技术研究所图书馆的可用数据进行手动整理。采用Kovat保留指数进行无标准品鉴别。结果从分析的44个牙齿样本中，共编目了11,971个内源性和外源性特征，包括没有合适库匹配的未知特征。在检测到的203种化合物中，鉴定出106种高保真匹配的化合物，涵盖45个毒物亚类。这些化合物中有89种是已知的发育毒物或内分泌干扰物。其余化合物是具有急性或慢性毒性数据的毒物，但没有发育或内分泌干扰活性数据。结论GCxGC-TOFMS可用于检测儿童牙齿中广泛的SVOCs，鉴定出大量发育毒性物质和其他有毒化学物质。这些化合物的检测凸显了我们对儿童接触化学物质的认识存在重大差距。

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引用次数: 0

Development of a laser desorption ionization – ion mobility – mass spectrometry method to accelerate the cyclic peptides stereochemistry determination workflow 建立了一种激光解吸电离-离子迁移-质谱法，以加快环多肽立体化学的测定工作流程

IF 1.7 3区化学 Q3 PHYSICS, ATOMIC, MOLECULAR & CHEMICAL

International Journal of Mass Spectrometry

Pub Date : 2025-09-23 DOI: 10.1016/j.ijms.2025.117533

Jia-Xuan Yan, Wendy Zhong

Cyclic peptides are a class of compounds with significant therapeutic potential. The increase in number of stereocenters resulting in exponential surge of stereoisomers poses an immense challenge on the stereochemical analysis of these molecules. Current stereochemistry control strategies for synthetic peptides requires chiral LC method development using synthetic markers. However, the synthesis of all possible stereoisomers as well as chiral LC method development to separate all of them is extremely costly and time consuming. Alternatively, cyclic peptides can be hydrolyzed into single amino acids (AA), further derivatized by chiral reagents for LC-MS analysis, and compared to AA standards subjected to identical derivatization protocols. This LC-MS based methodologies could determine chirality for all possible stereoisomers within short time (less than 1hr) avoiding the need to synthesize large number of cyclic peptide stereoisomers. While examining literature reported LC-MS methodologies, we sought opportunities to further reduce the analysis time required for comprehensive determinations of the stereochemistry of cyclic peptides via advanced MS platforms. Here-in we report a new laser desorption/ionization-ion mobility-mass spectrometry (LDI-IM-MS) method for the rapid determination of amino acid stereochemistry in cyclic peptides. Chiral derivatization reagents, l-FDLA (Nα-(2,4-dinitro-5-fluorophenyl)-l-leucinamide) and d-FDLA were used to derivatize the amino acids into diastereomer pairs. The diastereomers were differentiated using LDI-IM-MS on a Bruker timsTOF flex platform, with key ion mobility parameters optimized and experimental CCS (collision cross section) values calculated. Enhanced sample preparation workflow including solid phase extraction (SPE) and CuCl₂ doping exhibited better ion mobility differentiation for selected samples. This approach was successfully applied to the analysis of polymyxin B, a natural product cyclic peptide, providing comprehensive stereochemical determination of all constituent amino acids within 1 min. The new workflow not only accelerates the stereochemical analysis of cyclic peptides but also holds promise for broader applications in pharmaceuticals including chiral quality control and monitoring of peptide stability.

环肽是一类具有重要治疗潜力的化合物。立体中心数目的增加导致立体异构体的指数激增，对这些分子的立体化学分析提出了巨大的挑战。目前合成肽的立体化学控制策略需要利用合成标记开发手性LC方法。然而，所有可能的立体异构体的合成以及开发手性LC方法来分离它们是非常昂贵和耗时的。或者，环肽可以水解成单氨基酸（AA），通过手性试剂进一步衍生化用于LC-MS分析，并与AA标准品进行相同衍生化方案的比较。这种基于LC-MS的方法可以在短时间内（不到1小时）确定所有可能的立体异构体的手性，避免了合成大量环肽立体异构体的需要。在研究文献报道的LC-MS方法时，我们寻求机会进一步减少通过先进的MS平台全面测定环肽立体化学所需的分析时间。本文报道了一种新的激光解吸/电离-离子迁移-质谱（LDI-IM-MS）快速测定环状肽中氨基酸立体化学的方法。用手性衍生化试剂l-FDLA （n - α-（2,4-二硝基-5-氟苯基）-l-亮氨酸）和d-FDLA将氨基酸衍生成非对映体对。在Bruker timsTOF柔性平台上使用LDI-IM-MS对非对映体进行区分，优化关键离子迁移率参数并计算实验CCS（碰撞截面）值。固相萃取（SPE）和CuCl2掺杂等改进的样品制备流程对选定的样品表现出更好的离子迁移率分化。该方法成功地应用于天然产物环肽polymyxin B的分析，在1分钟内提供了所有组成氨基酸的全面立体化学测定。新的工作流程不仅加速了环肽的立体化学分析，而且还有望在药物领域得到更广泛的应用，包括手性质量控制和肽稳定性监测。

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引用次数: 0

Comparison of the results of the aberration approach for the calculation of electrostatic TOF mass analyzers with simulation in SIMION 用像差法计算静电TOF质量分析仪与SIMION仿真结果的比较

IF 1.7 3区化学 Q3 PHYSICS, ATOMIC, MOLECULAR & CHEMICAL

International Journal of Mass Spectrometry

Pub Date : 2025-09-10 DOI: 10.1016/j.ijms.2025.117526

Daniil D. Odintsov , Sergey S. Poteshin

In the last few years, high-resolution time-of-flight mass analyzers (TOF-MA) have been intensively developed. Their development requires tools that provide very accurate calculation of ion trajectories in electric fields, since an error on the scale of hundreds of picoseconds at millisecond flight times (10⁻¹⁰ %) already leads to noticeable distortions of the result. The main apparatus for calculating such systems is the aberration theory, but it has a limitation in the accuracy of calculations, since it is based on expansion in a series, and taking into account the next order of expansion significantly complicates the formulas. In this regard, using the example of calculating ion trajectories for TOF-MA with sector electrostatic fields, a comparison of the results, obtained using the aberration theory was carried out with the results of modeling in Simion. Results of the comparison indicate the possibility of applicability of the program for calculating multi-turn mass analyzers (MT-MA). Using the developed program, MT-MA with a resolution of 470,000 was calculated.

近年来，高分辨率飞行时间质量分析仪（TOF-MA）得到了广泛的发展。它们的开发需要提供非常精确的电场离子轨迹计算工具，因为在毫秒飞行时间（10 - 10%）的数百皮秒的误差已经导致结果的明显扭曲。计算这类系统的主要工具是像差理论，但它在计算精度上有局限性，因为它是基于一系列的展开，并且考虑到下一阶展开会使公式变得非常复杂。在此基础上，以扇形静电场下TOF-MA离子轨迹计算为例，将像差理论计算结果与Simion建模结果进行了比较。对比结果表明该程序适用于多转质分析仪（MT-MA）计算的可能性。利用开发的程序，计算了分辨率为47万的MT-MA。

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引用次数: 0