Nanostructure-initiator mass spectrometry: a protocol for preparing and applying NIMS surfaces for high-sensitivity mass analysis.
Nanostructure-initiator mass spectrometry (NIMS) is a new surface-based MS technique that uses a nanostructured surface to trap liquid ('initiator') compounds. Analyte materials adsorbed onto this 'clathrate' surface are subsequently released by laser irradiation for mass analysis. In this protocol, we describe the preparation of NIMS surfaces capable of producing low background and high-sensitivity mass spectrometric measurement using the initiator compound BisF17. Examples of analytes that adsorb to this surface are small molecules, drugs, lipids, carbohydrates and peptides. Typically, NIMS is used to analyze samples ranging from simple analytical standards and proteolytic digests to more complex samples such as tissues, cells and biofluids. Critical experimental considerations of NIMS are described. Specifically, NIMS sensitivity is examined as a function of pre-etch cleaning treatment, etching current density, etching time, initiator composition, sample concentration, sample deposition method and laser fluence. Typically, NIMS surface preparation can be completed in less than 2 h. Subsequent sample preparation requires 1-5 min, depending on sample deposition method. Mass spectrometric data acquisition typically takes 1-30 s per sample.
Woo
Hin-Koon
HK
Department of Molecular Biology, Scripps Center for Mass Spectrometry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Northen
Trent R
TR
Yanes
Oscar
O
Siuzdak
Gary
G
D000327:Adsorption; D002241:Carbohydrates / Q000737:chemistry; D006801:Humans; D007202:Indicators and Reagents; D008244:Lysophosphatidylcholines / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods*; D009020:Morphine / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods*; D010455:Peptides / Q000737:chemistry; D011405:Propafenone / Q000737:chemistry; D012825:Silicon / Q000737:chemistry; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013499:Surface Properties; D014556:Urine / Q000737:chemistry
D002241:Carbohydrates; D007202:Indicators and Reagents; D008244:Lysophosphatidylcholines; D010455:Peptides; C006065:We 201; D011405:Propafenone; D009020:Morphine; D012825:Silicon