1
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Gass DT, Quintero AV, Hatvany JB, Gallagher ES. Metal adduction in mass spectrometric analyses of carbohydrates and glycoconjugates. MASS SPECTROMETRY REVIEWS 2024; 43:615-659. [PMID: 36005212 DOI: 10.1002/mas.21801] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 07/22/2022] [Accepted: 07/25/2022] [Indexed: 06/15/2023]
Abstract
Glycans, carbohydrates, and glycoconjugates are involved in many crucial biological processes, such as disease development, immune responses, and cell-cell recognition. Glycans and carbohydrates are known for the large number of isomeric features associated with their structures, making analysis challenging compared with other biomolecules. Mass spectrometry has become the primary method of structural characterization for carbohydrates, glycans, and glycoconjugates. Metal adduction is especially important for the mass spectrometric analysis of carbohydrates and glycans. Metal-ion adduction to carbohydrates and glycoconjugates affects ion formation and the three-dimensional, gas-phase structures. Herein, we discuss how metal-ion adduction impacts ionization, ion mobility, ion activation and dissociation, and hydrogen/deuterium exchange for carbohydrates and glycoconjugates. We also compare the use of different metals for these various techniques and highlight the value in using metals as charge carriers for these analyses. Finally, we provide recommendations for selecting a metal for analysis of carbohydrate adducts and describe areas for continued research.
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Affiliation(s)
- Darren T Gass
- Department of Chemistry and Biochemistry, Baylor University, Waco, Texas, USA
| | - Ana V Quintero
- Department of Chemistry and Biochemistry, Baylor University, Waco, Texas, USA
| | - Jacob B Hatvany
- Department of Chemistry and Biochemistry, Baylor University, Waco, Texas, USA
| | - Elyssia S Gallagher
- Department of Chemistry and Biochemistry, Baylor University, Waco, Texas, USA
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2
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Wu YC, Zhang XW, Huang YC, Lu IC. Advancing carbohydrate quantification in MALDI mass spectrometry by the rapidly freeze-drying droplet (RFDD) method. Analyst 2024; 149:1766-1773. [PMID: 38372348 DOI: 10.1039/d3an02201c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Quantitative carbohydrate analysis faces challenges in matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS), including insufficient sensitivity and inconsistent spatial distribution of ion intensity. This study introduces an innovative sample preparation approach, the Rapidly Freeze-Drying Droplet (RFDD) method, aimed at overcoming these challenges by enhancing the homogeneity of the sample morphology and signal intensity in MALDI. Compared to conventional preparation methods, the RFDD method reduces the laser energy threshold and demonstrates a remarkable increase in signal intensity for carbohydrates, facilitating the detection of high-molecular-weight polysaccharides (>10 kDa). The RFDD-prepared samples exhibit a uniformly distributed signal intensity that overcomes the 'sweet spot' issue in MALDI. The enhanced signal intensity and reproducibility lead to reliable quantitative analysis of carbohydrates, eliminating the need for expensive isotopic standards in each sample. A straightforward and accessible approach is presented for general laboratories, revolutionizing carbohydrate analysis in MALDI-MS.
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Affiliation(s)
- Yu-Cheng Wu
- Department of Chemistry, National Chung Hsing University, Taichung City 40227, Taiwan.
| | - Xin-Wen Zhang
- Department of Chemistry, National Chung Hsing University, Taichung City 40227, Taiwan.
| | - Yi-Ching Huang
- Department of Chemistry, National Chung Hsing University, Taichung City 40227, Taiwan.
| | - I-Chung Lu
- Department of Chemistry, National Chung Hsing University, Taichung City 40227, Taiwan.
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3
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On-tissue amidation of sialic acid with aniline for sensitive imaging of sialylated N-glycans from FFPE tissue sections via MALDI mass spectrometry. Anal Bioanal Chem 2022; 414:5263-5274. [DOI: 10.1007/s00216-022-03894-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 12/24/2021] [Accepted: 01/10/2022] [Indexed: 01/06/2023]
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4
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Yang TL, Huang CL, Lee CP. Utilizing AgNPt-SALDI to Classify Edible Oils by Multivariate Statistics of Triacylglycerol Profile. Molecules 2021; 26:molecules26195880. [PMID: 34641425 PMCID: PMC8510378 DOI: 10.3390/molecules26195880] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 09/24/2021] [Accepted: 09/25/2021] [Indexed: 11/16/2022] Open
Abstract
Edible oils are valuable sources of nutrients, and their classification is necessary to ensure high quality, which is essential to food safety. This study reports the establishment of a rapid and straightforward SALDI-TOF MS platform used to detect triacylglycerol (TAG) in various edible oils. Silver nanoplates (AgNPts) were used to optimize the SALDI samples for high sensitivity and reproducibility of TAG signals. TAG fingerprints were combined with multivariate statistics to identify the critical features of edible oil discrimination. Eleven various edible oils were discriminated using principal component analysis (PCA). The results suggested the creation of a robust platform that can examine food adulteration and food fraud, potentially ensuring high-quality foods and agricultural products.
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Affiliation(s)
- Tzu-Ling Yang
- Department of Applied Chemistry, National Chiayi University, Chiayi City 60004, Taiwan; (T.-L.Y.); (C.-L.H.)
| | - Cheng-Liang Huang
- Department of Applied Chemistry, National Chiayi University, Chiayi City 60004, Taiwan; (T.-L.Y.); (C.-L.H.)
| | - Chu-Ping Lee
- Department of Chemistry, Fu Jen Catholic University, New Taipei City 24205, Taiwan
- Correspondence:
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5
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Harvey DJ. ANALYSIS OF CARBOHYDRATES AND GLYCOCONJUGATES BY MATRIX-ASSISTED LASER DESORPTION/IONIZATION MASS SPECTROMETRY: AN UPDATE FOR 2015-2016. MASS SPECTROMETRY REVIEWS 2021; 40:408-565. [PMID: 33725404 DOI: 10.1002/mas.21651] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 07/24/2020] [Indexed: 06/12/2023]
Abstract
This review is the ninth update of the original article published in 1999 on the application of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2016. Also included are papers that describe methods appropriate to analysis by MALDI, such as sample preparation techniques, even though the ionization method is not MALDI. Topics covered in the first part of the review include general aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, fragmentation and arrays. The second part of the review is devoted to applications to various structural types such as oligo- and poly-saccharides, glycoproteins, glycolipids, glycosides and biopharmaceuticals. Much of this material is presented in tabular form. The third part of the review covers medical and industrial applications of the technique, studies of enzyme reactions and applications to chemical synthesis. The reported work shows increasing use of combined new techniques such as ion mobility and the enormous impact that MALDI imaging is having. MALDI, although invented over 30 years ago is still an ideal technique for carbohydrate analysis and advancements in the technique and range of applications show no sign of deminishing. © 2020 Wiley Periodicals, Inc.
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Affiliation(s)
- David J Harvey
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, Roosevelt Drive, Oxford, OX3 7FZ, United Kingdom
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6
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Tabandeh S, Lemus CE, Leon L. Deciphering the Role of π-Interactions in Polyelectrolyte Complexes Using Rationally Designed Peptides. Polymers (Basel) 2021; 13:2074. [PMID: 34202468 PMCID: PMC8271475 DOI: 10.3390/polym13132074] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 06/18/2021] [Accepted: 06/21/2021] [Indexed: 11/16/2022] Open
Abstract
Electrostatic interactions, and specifically π-interactions play a significant role in the liquid-liquid phase separation of proteins and formation of membraneless organelles/or biological condensates. Sequence patterning of peptides allows creating protein-like structures and controlling the chemistry and interactions of the mimetic molecules. A library of oppositely charged polypeptides was designed and synthesized to investigate the role of π-interactions on phase separation and secondary structures of polyelectrolyte complexes. Phenylalanine was chosen as the π-containing residue and was used together with lysine or glutamic acid in the design of positively or negatively charged sequences. The effect of charge density and also the substitution of fluorine on the phenylalanine ring, known to disrupt π-interactions, were investigated. Characterization analysis using MALDI-TOF mass spectroscopy, H NMR, and circular dichroism (CD) confirmed the molecular structure and chiral pattern of peptide sequences. Despite an alternating sequence of chirality previously shown to promote liquid-liquid phase separation, complexes appeared as solid precipitates, suggesting strong interactions between the sequence pairs. The secondary structures of sequence pairs showed the formation of hydrogen-bonded structures with a β-sheet signal in FTIR spectroscopy. The presence of fluorine decreased hydrogen bonding due to its inhibitory effect on π-interactions. π-interactions resulted in enhanced stability of complexes against salt, and higher critical salt concentrations for complexes with more π-containing amino acids. Furthermore, UV-vis spectroscopy showed that sequences containing π-interactions and increased charge density encapsulated a small charged molecule with π-bonds with high efficiency. These findings highlight the interplay between ionic, hydrophobic, hydrogen bonding, and π-interactions in polyelectrolyte complex formation and enhance our understanding of phase separation phenomena in protein-like structures.
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Affiliation(s)
- Sara Tabandeh
- Department of Materials Science and Engineering, University of Central Florida, Orlando, FL 32816, USA;
| | | | - Lorraine Leon
- Department of Materials Science and Engineering, University of Central Florida, Orlando, FL 32816, USA;
- NanoScience Technology Center, University of Central Florida, Orlando, FL 32826, USA
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7
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Lin HY, Dyakov YA, Lee YT, Ni CK. Temperature Dependence of Desorbed Ions and Neutrals and Ionization Mechanism of Matrix-Assisted Laser Desorption/Ionization. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:95-105. [PMID: 32239933 DOI: 10.1021/jasms.0c00101] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Two separate temperature-dependent experiments were performed to investigate the ionization mechanism of ultraviolet matrix-assisted laser desorption/ionization (UV-MALDI) of matrix 2,5-dihydroxybenzoic acid (2,5-DHB). First, the angular resolved intensity and velocity distributions of neutrals desorbed from the 2,5-DHB solid sample through UV laser (355 nm) pulse irradiation were measured using a rotating quadrupole mass spectrometer. Second, the desorbed neutrals, at an angle normal to the surface, and the desorbed ions were simultaneously detected for each laser shot using the quadrupole mass spectrometer and a time-of-flight mass spectrometer, respectively. Both experiments were conducted at two initial temperatures: 100 and 300 K. The measurements from these two experiments were used to calculate the initial temperature dependence of the ion-to-neutral ratio. The results closely agreed with the predictions of the temperature-dependent ion-to-neutral ratio using the thermal model, indicating that thermally induced proton transfer is the dominant reaction that generates initial ions of 2,5-DHB in UV-MALDI.
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Affiliation(s)
- Hou-Yu Lin
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
- Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan
| | - Yuri A Dyakov
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
| | - Yuan Tseh Lee
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
| | - Chi-Kung Ni
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
- Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
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8
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Lee C, Inutan ED, Chen JL, Mukeku MM, Weidner SM, Trimpin S, Ni CK. Toward understanding the ionization mechanism of matrix-assisted ionization using mass spectrometry experiment and theory. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2021; 35 Suppl 1:e8382. [PMID: 30623523 DOI: 10.1002/rcm.8382] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Accepted: 01/03/2019] [Indexed: 06/09/2023]
Abstract
RATIONALE Matrix-assisted ionization (MAI) mass spectrometry does not require voltages, a laser beam, or added heat to initiate ionization, but it is strongly dependent on the choice of matrix and the vacuum conditions. High charge state distributions of nonvolatile analyte ions produced by MAI suggest that the ionization mechanism may be similar to that of electrospray ionization (ESI), but different from matrix-assisted laser desorption/ionization (MALDI). While significant information is available for MAI using mass spectrometers operating at atmospheric and intermediate pressure, little is known about the mechanism at high vacuum. METHODS Eleven MAI matrices were studied on a high-vacuum time-of-flight (TOF) mass spectrometer using a 266 nm pulsed laser beam under otherwise typical MALDI conditions. Detailed comparisons with the commonly used MALDI matrices and theoretical prediction were made for 3-nitrobenzonitrile (3-NBN), which is the only MAI matrix that works well in high vacuum when irradiated with a laser. RESULTS Screening of MAI matrices with good absorption at 266 nm but with various degrees of volatility and laser energies suggests that volatility and absorption at the laser wavelength may be necessary, but not sufficient, criteria to explain the formation of multiply charged analyte ions. 3-NBN produces intact, highly charged ions of nonvolatile analytes in high-vacuum TOF with the use of a laser, demonstrating that ESI-like ions can be produced in high vacuum. Theoretical calculations and mass spectra suggest that thermally induced proton transfer, which is the major ionization mechanism in MALDI, is not important with the 3-NBN matrix at 266 nm laser wavelength. 3-NBN:analyte crystal morphology is, however, important in ion generation in high vacuum. CONCLUSIONS The 3-NBN MAI matrix produces intact, highly charged ions of nonvolatile compounds in high-vacuum TOF mass spectrometers with the aid of ablation and/or heating by laser irradiation, and shows a different ionization mechanism from that of typical MALDI matrices.
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Affiliation(s)
- Chuping Lee
- Department of Chemistry, Wayne State University, Detroit, MI, USA
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan
| | - Ellen D Inutan
- Department of Chemistry, Mindanao State University-Iligan Institute of Technology, Iligan City, Philippines
| | - Jien Lian Chen
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan
| | - Mutanu M Mukeku
- Department of Chemistry, Wayne State University, Detroit, MI, USA
| | - Steffen M Weidner
- Bundesanstalt für Materialforschung und-prüfung, Richard-Willstätter-Straße 11, 12489, Berlin, Germany
| | - Sarah Trimpin
- Department of Chemistry, Wayne State University, Detroit, MI, USA
| | - Chi-Kung Ni
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan
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9
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Heijs B, Potthoff A, Soltwisch J, Dreisewerd K. MALDI-2 for the Enhanced Analysis of N-Linked Glycans by Mass Spectrometry Imaging. Anal Chem 2020; 92:13904-13911. [PMID: 32975931 PMCID: PMC7581013 DOI: 10.1021/acs.analchem.0c02732] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
![]()
N-glycans are important players in a variety of
pathologies including different types of cancer, (auto)immune diseases,
and also viral infections. Matrix-assisted laser desorption/ionization
mass spectrometry (MALDI-MS) is an important tool for high-throughput N-glycan profiling and, upon use of tandem MS, for structure
determination. By use of MALDI-MS imaging (MSI) in combination with
PNGase F treatment, also spatially correlated N-glycan
profiling from tissue sections becomes possible. Here we coupled laser-induced
postionization, or MALDI-2, to a trapped ion mobility quadrupole time-of-flight
mass spectrometer (timsTOF fleX MALDI-2, Bruker Daltonics). We demonstrate
that with MALDI-2 the sensitivity for the detection of molecular [M
– H]− species of N-glycans
increased by about 3 orders of magnitude. Compared to the current
gold standard, the positive ion mode analysis of [M + Na]+ adducts, a sensitivity increase by about a factor of 10 is achieved.
By exploiting the advantageous fragmentation behavior of [M –
H]− ions, exceedingly rich structural information
on the composition of complex N-glycans was moreover
obtained directly from thin tissue sections of human cerebellum and
upon use of low-energy collision-induced dissociation tandem MS. In
another set of experiments, in this case by use of a modified Synapt
G2-S QTOF mass spectrometer (Waters), we investigated the influence
of relevant input parameters, in particular pressure of the N2 cooling gas in the ion source, delay between the two laser
pulses, and that of their pulse energies. In this way, analytical
conditions were identified at which molecular ion abundances were
maximized and fragmentation reactions minimized. The use of negative
ion mode MALDI-2-MSI could constitute a valuable tool in glycobiology
research.
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Affiliation(s)
- Bram Heijs
- Institute of Hygiene, University of Münster, Robert-Koch-Str. 41, 48149 Münster, Germany.,Center for Proteomics and Metabolomics, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Alexander Potthoff
- Institute of Hygiene, University of Münster, Robert-Koch-Str. 41, 48149 Münster, Germany
| | - Jens Soltwisch
- Institute of Hygiene, University of Münster, Robert-Koch-Str. 41, 48149 Münster, Germany.,Interdisciplinary Center for Clinical Research (IZKF), University of Münster, Domagkstr. 3, 48149 Münster, Germany
| | - Klaus Dreisewerd
- Institute of Hygiene, University of Münster, Robert-Koch-Str. 41, 48149 Münster, Germany.,Interdisciplinary Center for Clinical Research (IZKF), University of Münster, Domagkstr. 3, 48149 Münster, Germany
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10
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Nguyen HQ, Lee D, Kim Y, Paek M, Kim M, Jang KS, Oh J, Lee YS, Yeon JE, Lubman DM, Kim J. Platelet Factor 4 as a Novel Exosome Marker in MALDI-MS Analysis of Exosomes from Human Serum. Anal Chem 2019; 91:13297-13305. [PMID: 31549806 DOI: 10.1021/acs.analchem.9b04198] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Exosomes are nanosized vesicles commonly found in biological fluids as a result of a secretion process involving endosomes and multivesicular bodies. The isolation and analysis of exosomes can be useful for noninvasive clinical diagnosis of a variety of human diseases. We investigated the utility of analyzing exosomal proteins, using matrix-assisted laser desorption/ionization combined with Fourier-transform ion cyclotron resonance mass spectrometry (MALDI-FTICR-MS), as a means of determining the presence of exosomes. MALDI-FTICR-MS analyses of exosomes enriched from human serum via centrifugation in a mass range of m/z 1000-20 000 yielded a distinctive protein around m/z 7766. The high mass accuracy and resolution of MALDI-FTICR-MS allowed for reliable comparisons against a protein database, through which the protein was identified as platelet factor 4 (PLF4), whose singly charged protein peak has an elemental composition of C341H577N96O101S4+, with a theoretical most abundant isotopic peak at m/z 7765.194 and a theoretical average peak at m/z 7766. The MALDI-TOF MS analysis of exosomes from the serum of 27 patients with different states of liver diseases provided the most abundant PLF4 peak for each mass spectrum, along with several additional minor peaks. In conclusion, MALDI-MS is suitable as an alternative exosome detection method, serving as a valuable confirmation tool, greatly decreasing the time and workload associated with exosome identification.
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Affiliation(s)
- Huu-Quang Nguyen
- Department of Chemistry , Chungnam National University , Daejeon , Republic of Korea
| | - Dabin Lee
- Department of Chemistry , Chungnam National University , Daejeon , Republic of Korea
| | - Yeoseon Kim
- Department of Chemistry , Chungnam National University , Daejeon , Republic of Korea
| | - Minseok Paek
- Department of Chemistry , Chungnam National University , Daejeon , Republic of Korea
| | - Minsun Kim
- Scientific Instruments Reliability Assessment Center , Korea Basic Science Institute , Daejeon , Republic of Korea
| | - Kyoung-Soon Jang
- Biomedical Omics Center , Korea Basic Science Institute , Cheongju , Republic of Korea
| | - Jooyeon Oh
- ASTA Corporation , Suwon-si , Gyeonggi-Do , Republic of Korea
| | - Young-Sun Lee
- Department of Internal Medicine , Korea University College of Medicine , Seoul , South Korea
| | - Jong Eun Yeon
- Department of Internal Medicine , Korea University College of Medicine , Seoul , South Korea
| | - David M Lubman
- Department of Surgery , University of Michigan Medical Center , Ann Arbor , Michigan 48109 , United States
| | - Jeongkwon Kim
- Department of Chemistry , Chungnam National University , Daejeon , Republic of Korea
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11
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Chong YK, Ho CC, Leung SY, Lau SK, Woo PC. Clinical Mass Spectrometry in the Bioinformatics Era: A Hitchhiker's Guide. Comput Struct Biotechnol J 2018; 16:316-334. [PMID: 30237866 PMCID: PMC6138949 DOI: 10.1016/j.csbj.2018.08.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 08/20/2018] [Accepted: 08/21/2018] [Indexed: 02/06/2023] Open
Abstract
Mass spectrometry (MS) is a sensitive, specific and versatile analytical technique in the clinical laboratory that has recently undergone rapid development. From initial use in metabolic profiling, it has matured into applications including clinical toxicology assays, target hormone and metabolite quantitation, and more recently, rapid microbial identification and antimicrobial resistance detection by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). In this mini-review, we first succinctly outline the basics of clinical mass spectrometry. Examples of hard ionization (electron ionization) and soft ionization (electrospray ionization, MALDI) are presented to demonstrate their clinical applications. Next, a conceptual discourse on mass selection and determination is presented: quadrupole mass filter, time-of-flight mass spectrometer and the Orbitrap; and MS/MS (tandem-in-space, tandem-in-time and data acquisition), illustrated with clinical examples. Current applications in (1) bacterial and fungal identification, antimicrobial susceptibility testing and phylogenetic classification, (2) general unknown urine toxicology screening and expanded new-born metabolic screening and (3) clinical metabolic profiling by gas chromatography are outlined. Finally, major limitations of MS-based techniques, including the technical challenges of matrix effect and isobaric interference; and novel challenges in the post-genomic era, such as protein molecular variants, are critically discussed from the perspective of service laboratories. Computer technology and structural biology have played important roles in the maturation of this field. MS-based techniques have the potential to replace current analytical techniques, and existing expertise and instrument will undergo rapid evolution. Significant automation and adaptation to regulatory requirements are underway. Mass spectrometry is unleashing its potentials in clinical laboratories.
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Affiliation(s)
- Yeow-Kuan Chong
- Hospital Authority Toxicology Reference Laboratory, Department of Pathology, Princess Margaret Hospital (PMH), Kowloon, Hong Kong
- Chemical Pathology and Medical Genetics, Department of Pathology, Princess Margaret Hospital (PMH), Kowloon, Hong Kong
| | - Chi-Chun Ho
- Division of Chemical Pathology, Department of Clinical Pathology, Pamela Youde Nethersole Eastern Hospital (PYNEH), Hong Kong
- Division of Clinical Biochemistry, Department of Pathology, Queen Mary Hospital (QMH), Hong Kong
- Centre for Genomic Sciences, The University of Hong Kong, Hong Kong
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong
| | - Shui-Yee Leung
- Department of Ocean Science, School of Science, The Hong Kong University of Science and Technology, Kowloon, Hong Kong
| | - Susanna K.P. Lau
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, The University of Hong Kong, Hong Kong
- Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong
- Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The University of Hong Kong, Hong Kong
| | - Patrick C.Y. Woo
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, The University of Hong Kong, Hong Kong
- Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong
- Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The University of Hong Kong, Hong Kong
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12
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Liang SP, Lu IC, Tsai ST, Chen JL, Lee YT, Ni CK. Laser Pulse Width Dependence and Ionization Mechanism of Matrix-Assisted Laser Desorption/Ionization. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:2235-2245. [PMID: 28707193 DOI: 10.1007/s13361-017-1734-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 01/24/2017] [Accepted: 06/05/2017] [Indexed: 06/07/2023]
Abstract
Ultraviolet laser pulses at 355 nm with variable pulse widths in the region from 170 ps to 1.5 ns were used to investigate the ionization mechanism of matrix-assisted laser desorption/ionization (MALDI) for matrices 2,5-dihydroxybenzoic acid (DHB), α-cyano-4-hydroxycinnamic acid (CHCA), and sinapinic acid (SA). The mass spectra of desorbed ions and the intensity and velocity distribution of desorbed neutrals were measured simultaneously for each laser shot. These quantities were found to be independent of the laser pulse width. A comparison of the experimental measurements and numerical simulations according to the multiphoton ionization, coupled photophysical and chemical dynamics (CPCD), and thermally induced proton transfer models showed that the predictions of thermally induced proton transfer model were in agreement with the experimental data, but those of the multiphoton ionization model were not. Moreover, the predictions of the CPCD model based on singlet-singlet energy pooling were inconsistent with the experimental data of CHCA and SA, but were consistent with the experimental data of DHB only when some parameters used in the model were adjusted to extreme values. Graphical Abstract ᅟ.
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Affiliation(s)
- Sheng-Ping Liang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan
| | - I-Chung Lu
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA
| | - Shang-Ting Tsai
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan
| | - Jien-Lian Chen
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan
| | - Yuan Tseh Lee
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan
| | - Chi-Kung Ni
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan.
- Department of Chemistry, National Tsing Hua University, Hsinchu, 30013, Taiwan.
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13
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Lai YH, Wang YS. Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry: Mechanistic Studies and Methods for Improving the Structural Identification of Carbohydrates. Mass Spectrom (Tokyo) 2017; 6:S0072. [PMID: 28959517 PMCID: PMC5610957 DOI: 10.5702/massspectrometry.s0072] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 08/03/2017] [Indexed: 12/21/2022] Open
Abstract
Although matrix-assisted laser desorption/ionization (MALDI) mass spectrometry is one of the most widely used soft ionization methods for biomolecules, the lack of detailed understanding of ionization mechanisms restricts its application in the analysis of carbohydrates. Structural identification of carbohydrates achieved by MALDI mass spectrometry helps us to gain insights into biological functions and pathogenesis of disease. In this review, we highlight mechanistic details of MALDI, including both ionization and desorption. Strategies to improve the ion yield of carbohydrates are also reviewed. Furthermore, commonly used fragmentation methods to identify the structure are discussed.
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14
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Affiliation(s)
- Patricia M Peacock
- First State IR, LLC , 118 Susan Drive, Hockessin, Delaware 19707, United States
| | - Wen-Jing Zhang
- Department of Chemistry, Wayne State University , 5101 Cass Avenue, Detroit, Michigan 48202, United States
| | - Sarah Trimpin
- Department of Chemistry, Wayne State University , 5101 Cass Avenue, Detroit, Michigan 48202, United States
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