Matrix (mass spectrometry)

This article is about ionization assisting compounds for mass spectrometry. For the non-analyte components of a sample, see matrix (chemical analysis).

In mass spectrometry, a matrix is a compound that promotes the formation of ions. Matrix compounds are used in matrix-assisted laser desorption/ionization (MALDI), matrix-assisted ionization (MAI), and fast atom bombardment (FAB).

Matrix-assisted laser desorption/ionization

MALDI is an ionization technique where laser energy is absorbed by a matrix to create ions from large molecules without fragmentation. The matrix, typically in excess, is mixed with the analyte molecule and deposited on a target. A table of matrix compounds, their structures, laser wavelengths typically used, and typical application is shown below.

MALDI Matrix List

Compound	Abbreviation	Structure	Wavelength (nm)	Applications
9-aminoacridine[1]	9AA		337	lipids, metabolites
α-cyano-4-hydroxycinnamic acid[2]	CHCA		337, 355	peptides, lipids, nucleotides
ferulic acid[3][4]	FA		337, 355, 266	proteins
2,5-dihydroxy benzoic acid|[5]	DHB		337, 355	peptides, nucleotides, oligonucleotides, oligosaccharides
3-hydroxy picolinic acid[6]	HPA		337, 355	oligonucleotides
picolinic acid[7]	PA		266	oligonucleotides
sinapinic acid[3][4]	SA		337, 355, 266	peptides, proteins, lipids

Matrix-assisted ionization

Matrix-assisted ionization is an ionization method in mass spectrometry that creates ions via the creation of particles at atmospheric pressure and transfer to the vacuum of the mass analyzer.^[8]

List of Matrix-assisted Ionization Compounds^[9]

Compound	Abbreviation	Structure
2,5-dihydroxybenzoic acid	DHB
2-aminobenzyl alcohol
anthranilic acid
2-hydroxyacetophenone

Fast atom bombardment

FAB uses a high energy beam of atoms directed at a surface to create ions.^[10] FAB matrix compounds are typically liquids.

FAB Matrix List

Compound	Abbreviation	Structure
glycerol
thioglycerol
3-nitrobenzyl alcohol	NBA
18-crown-6 ether
2-nitrophenyloctyl ether	NPOE
diethanolamine
triethanolamine

See also

• Desorption/ionization on silicon

References

1. Vermillion-Salsbury, Rachal L.; Hercules, David M. (2002). "9-Aminoacridine as a matrix for negative mode matrix-assisted laser desorption/ionization". Rapid Communications in Mass Spectrometry. 16 (16): 1575–1581. doi:10.1002/rcm.750. ISSN 0951-4198.
2. Beavis, R. C.; Chaudhary, T.; Chait, B. T. (1992). "α-Cyano-4-hydroxycinnamic acid as a matrix for matrix-assisted laser desorption mass spectrometry". Organic Mass Spectrometry. 27 (2): 156–8. doi:10.1002/oms.1210270217.
3. Beavis, R. C.; Chait, B. T.; Standing, K. G. (1989). "Matrix-assisted laser-desorption mass spectrometry using 355 nm radiation". Rapid Communications in Mass Spectrometry. 3 (12): 436–9. Bibcode:1989RCMS....3..436B. doi:10.1002/rcm.1290031208. PMID 2520224.
4. Beavis, R. C.; Chait, B. T.; Fales, H. M. (1989). "Cinnamic acid derivatives as matrices for ultraviolet laser desorption mass spectrometry of proteins". Rapid Communications in Mass Spectrometry. 3 (12): 432–5. Bibcode:1989RCMS....3..432B. doi:10.1002/rcm.1290031207. PMID 2520223.
5. Strupat, K.; Karas, M.; Hillenkamp, F. (1991). "2,5-Dihidroxybenzoic acid: A new matrix for laser desorption—ionization mass spectrometry". International Journal of Mass Spectrometry and Ion Processes. 72 (111): 89–102. Bibcode:1991IJMSI.111...89S. doi:10.1016/0168-1176(91)85050-V.
6. Wu, K. J.; Steding, A.; Becker, C. H. (1993). "Matrix-assisted laser desorption time-of-flight mass spectrometry of oligonucleotides using 3-hydroxypicolinic acid as an ultraviolet-sensitive matrix". Rapid Communications in Mass Spectrometry. 7 (2): 142–6. Bibcode:1993RCMS....7..142W. doi:10.1002/rcm.1290070206. PMID 8457722.
7. Tang, K.; Taranenko, N. I.; Allman, S. L.; Cháng, L. Y.; Chen, C. H.; Lubman, D. M. (1994). "Detection of 500-nucleotide DNA by laser desorption mass spectrometry". Rapid Communications in Mass Spectrometry. 8 (9): 727–30. Bibcode:1994RCMS....8..727T. doi:10.1002/rcm.1290080913. PMID 7949335.
8. Peacock, Patricia M.; Zhang, Wen-Jing; Trimpin, Sarah (2017). "Advances in Ionization for Mass Spectrometry". Analytical Chemistry. 89 (1): 372–388. doi:10.1021/acs.analchem.6b04348. ISSN 0003-2700.
9. Li, Jing; Inutan, Ellen D.; Wang, Beixi; Lietz, Christopher B.; Green, Daniel R.; Manly, Cory D.; Richards, Alicia L.; Marshall, Darrell D.; Lingenfelter, Steven; Ren, Yue; Trimpin, Sarah (2012). "Matrix Assisted Ionization: New Aromatic and Nonaromatic Matrix Compounds Producing Multiply Charged Lipid, Peptide, and Protein Ions in the Positive and Negative Mode Observed Directly from Surfaces". Journal of the American Society for Mass Spectrometry. 23 (10): 1625–1643. Bibcode:2012JASMS..23.1625L. doi:10.1007/s13361-012-0413-z. ISSN 1044-0305.
10. Morris HR, Panico M, Barber M, Bordoli RS, Sedgwick RD, Tyler A (1981). "Fast atom bombardment: a new mass spectrometric method for peptide sequence analysis". Biochem. Biophys. Res. Commun. 101 (2): 623–31. doi:10.1016/0006-291X(81)91304-8. PMID 7306100.