title: Analysis of amphiphilic lipids and hydrophobic proteins using nonresonant femtosecond laser vaporization with electrospray post-ionization.
abstract: Amphiphilic lipids and hydrophobic proteins are vaporized at atmospheric pressure using nonresonant 70 femtosecond (fs) laser pulses followed by electrospray post-ionization prior to being transferred into a time-of-flight mass spectrometer for mass analysis. Measurements of molecules on metal and transparent dielectric surfaces indicate that vaporization occurs through a nonthermal mechanism. The molecules analyzed include the lipids 1-monooleoyl-rac-glycerol, 1,2-dihexanoyl-sn-glycero-3-phosphocholine, 1,2-dimyristoyl-sn-glycero-3-phosphocholine, and the hydrophobic proteins gramicidin A, B, and C. Vaporization of lipids from blood and milk are also presented to demonstrate that lipids in complex systems can be transferred intact into the gas phase for mass analysis.
authors.affiliation: Center for Advanced Photonics Research, Department of Chemistry, Temple University, 1901 N 13th Street, Philadelphia, PA 19122, USA.
authors.forename: John J
authors.initials: JJ
authors.lastname: Brady
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: Judge
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Levis
mesh_terms: D006096:Gramicidin / Q000737:chemistry*; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D008894:Milk Proteins / Q000737:chemistry*; D008958:Models, Molecular; D010713:Phosphatidylcholines / Q000097:blood / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation / Q000379:methods*; D014835:Volatilization
chemical_list: D008894:Milk Proteins; D010713:Phosphatidylcholines; D006096:Gramicidin