title: Mass spectrometry of DNA mixtures by laser ablation from frozen aqueous solution.
abstract: We report time-of-flight mass spectra of test mixtures of six single-stranded DNA segments. The segments range in size from 8 to 60 nucleotides (molecular weight range 2413 to 18,602 Da). The best mass spectra were obtained by pulsed laser ablation of thin frozen films of an aqueous solution of the mixture from an oxidized copper substrate. These mass spectra are dominated by the molecular-ion peak for each DNA segment, and show little evidence of fragmentation, peak broadening or cluster formation. In contrast, mass spectra obtained using UV laser ablation from an anthranilic acid matrix yield broad peaks with evidence of fragmentation, and DNA segments longer than 26 nucleotides are difficult to detect.
authors.affiliation: Department of Chemistry and Biochemistry, Arizona State University, Tempe 85287-1604.
authors.forename: D M
authors.initials: DM
authors.lastname: Schieltz
authors.forename: C W
authors.initials: CW
authors.lastname: Chou
authors.forename: C W
authors.initials: CW
authors.lastname: Luo
authors.forename: R M
authors.initials: RM
authors.lastname: Thomas
authors.forename: P
authors.initials: P
authors.lastname: Williams
mesh_terms: D001483:Base Sequence; D004277:DNA, Single-Stranded / Q000737:chemistry*; D005615:Freezing; D007834:Lasers; D013058:Mass Spectrometry / Q000379:methods*; D008969:Molecular Sequence Data; D012996:Solutions; D014867:Water / Q000737:chemistry
chemical_list: D004277:DNA, Single-Stranded; D012996:Solutions; D014867:Water