Laser Ablation Electrospray Ionization for Atmospheric Pressure, in Vivo, and Imaging Mass Spectrometry

• Published in: Analytical chemistry (Washington) Vol. 79; no. 21; pp. 8098 - 8106
• Main Authors: Nemes, Peter, Vertes, Akos
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 01.11.2007
• Subjects: Analytical chemistry; Atmospheric Pressure; Body fluids; Humans; Ions; Mass spectrometry; Molecular Weight; Organisms; Particle Size; Plant Leaves - chemistry; Plant Roots - chemistry; Plant Stems - chemistry; Proteins - analysis; Reserpine - analysis; Seedlings - chemistry; Seeds; Sensitivity and Specificity; Spectrometry, Mass, Electrospray Ionization - methods; Spectroscopy, Fourier Transform Infrared - methods; Spectrum analysis; Tagetes - chemistry; Terfenadine - administration & dosage; Terfenadine - analogs & derivatives; Terfenadine - analysis; Terfenadine - urine; Verapamil - analysis
• ISSN: 0003-2700; 1520-6882
• DOI: 10.1021/ac071181r

Mass spectrometric analysis of biomolecules under ambient conditions promises to enable the in vivo investigation of diverse biochemical changes in organisms with high specificity. Here we report on a novel combination of infrared laser ablation with electrospray ionization (LAESI) as an ambient ion source for mass spectrometry. As a result of the interactions between the ablation plume and the spray, LAESI accomplishes electrospray-like ionization. Without any sample preparation or pretreatment, this technique was capable of detecting a variety of molecular classes and size ranges (up to 66 kDa) with a detection limit of 8 and 25 fmol for verapamil and reserpine, respectively, and quantitation capabilities with a four-decade dynamic range. We demonstrated the utility of LAESI in a broad variety of applications ranging from plant biology to clinical analysis. Proteins, lipids, and metabolites were identified, and antihistamine excretion was followed via the direct analysis of bodily fluids (urine, blood, and serum). We also performed in vivo spatial profiling (on leaf, stem, and root) of metabolites in a French marigold (Tagetes patula) seedling.