title: High Sensitivity Analysis of Nanoliter Volumes of Volatile and Nonvolatile Compounds using Matrix Assisted Ionization (MAI) Mass Spectrometry.
abstract: First results are reported using a simple, fast, and reproducible matrix-assisted ionization (MAI) sample introduction method that provides substantial improvements relative to previously published MAI methods. The sensitivity of the new MAI methods, which requires no laser, high voltage, or nebulizing gas, is comparable to those reported for MALDI-TOF and n-ESI. High resolution full acquisition mass spectra having low chemical background are acquired from low nanoliters of solution using only a few femtomoles of analyte. The limit-of-detection for angiotensin II is less than 50 amol on an Orbitrap Exactive mass spectrometer. Analysis of peptides, including a bovine serum albumin digest, and drugs, including drugs in urine without a purification step, are reported using a 1 μL zero dead volume syringe in which only the analyte solution wetting the walls of the syringe needle is used in the analysis.
authors.affiliation: University of the Sciences, Philadelphia, PA, USA.
authors.forename: Khoa
authors.initials: K
authors.lastname: Hoang
authors.affiliation: MSTM, LLC, Newark, DE, USA.
authors.forename: Milan
authors.initials: M
authors.lastname: Pophristic
authors.affiliation: University of Delaware, Newark, DE, USA.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Horan
authors.affiliation: University of Delaware, Newark, DE, USA.
authors.forename: Murray V
authors.initials: MV
authors.lastname: Johnston
authors.affiliation: University of the Sciences, Philadelphia, PA, USA. c.mcewen@usciences.edu.|MSTM, LLC, Newark, DE, USA. c.mcewen@usciences.edu.
authors.forename: Charles N
authors.initials: CN
authors.lastname: McEwen
mesh_terms: D008970:Molecular Weight; D010455:Peptides / Q000032:analysis*; D012710:Serum Albumin, Bovine; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D010455:Peptides; D012710:Serum Albumin, Bovine
keywords: Azithromycin; Bovine serum albumin digest; Drugs; Inlet ionization; Ionization; LSD in urine; MAI; MALDI; Matrix-assisted Ionization; Peptide; Sensitivity; nano-ESI