Biomaterial Database

Atmospheric pressure MALDI/ion trap mass spectrometry. 2000

V V Laiko, and S C Moyer, and R J Cotter

Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.

A new sample ionization technique, atmospheric pressure matrix-assisted laser desorption/ionization (AP MALDI), was coupled with a commercial ion trap mass spectrometer. This configuration enables the application-specific selection of external atmospheric ionization sources: the electrospray/APCI (commercially available) and AP MALDI (built in-house), which can be readily interchanged within minutes. The detection limit of the novel AP MALDI/ion trap is 10-50 fmol of analyte deposited on the target surface for a four-component mixture of peptides with 800-1700 molecular weight. The possibility of peptide structural analysis by MS/MS and MS3 experiments for AP MALDI-generated ions was demonstrated for the first time.

UI	MeSH Term	Description	Entries
D010455	Peptides	Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are considered to be larger versions of peptides that can form into complex structures such as ENZYMES and RECEPTORS.	Peptide,Polypeptide,Polypeptides
D019032	Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization	A mass spectrometric technique that is used for the analysis of large biomolecules. Analyte molecules are embedded in an excess matrix of small organic molecules that show a high resonant absorption at the laser wavelength used. The matrix absorbs the laser energy, thus inducing a soft disintegration of the sample-matrix mixture into free (gas phase) matrix and analyte molecules and molecular ions. In general, only molecular ions of the analyte molecules are produced, and almost no fragmentation occurs. This makes the method well suited for molecular weight determinations and mixture analysis.	Laser Desorption-Ionization Mass Spectrometry, Matrix-Assisted,MALD-MS,MALDI,Mass Spectrometry, Matrix-Assisted Laser Desorption-Ionization,Mass Spectroscopy, Matrix-Assisted Laser Desorption-Ionization,Matrix-Assisted Laser Desorption-Ionization Mass Spectrometry,Spectroscopy, Mass, Matrix-Assisted Laser Desorption-Ionization,MALDI-MS,MS-MALD,SELDI-TOF-MS,Surface Enhanced Laser Desorption Ionization Mass Spectrometry,Laser Desorption Ionization Mass Spectrometry, Matrix Assisted,MALDI MS,Mass Spectrometry, Matrix Assisted Laser Desorption Ionization,Mass Spectroscopy, Matrix Assisted Laser Desorption Ionization,Matrix Assisted Laser Desorption Ionization Mass Spectrometry