title: Quantitative analysis of oligonucleotides by matrix-assisted laser desorption/ionization mass spectrometry.
abstract: Quantitative aspects of oligonucleotide analysis by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry remain largely unexplored relative to the efforts that have been devoted to quantitative peptide and protein analysis. The successful quantitation of these other biopolymers coupled with the potential of rapid nucleic acid analysis by desorption/ionization techniques prompted the present investigation into quantifying mixed base oligonucleotides of intermediate molecular weights. This report describes the concentration-dependent desorption/ionization of a 21-base oligonucleotide (MW 6361) using a 36-base oligonucleotide (MW 11 131) as an internal standard. Peak height and peak area ratios (analyte to internal standard) varied linearly as a function of oligonucleotide concentration (R2 = 0.966 and 0.991, respectively). The linearity of response extended over nearly three orders of magnitude, from 0.125 to 100 pmol of analyte applied. The use of an internal standard improved the linearity of the calibration curve and reduced relative standard deviations. These results demonstrate for the first time the quantitation of medium size oligonucleotides using MALDI.
authors.affiliation: Department of Food Science and Technology, University of California, Davis 95616, USA.
authors.forename: B A
authors.initials: BA
authors.lastname: Bruenner
authors.forename: T T
authors.initials: TT
authors.lastname: Yip
authors.forename: T W
authors.initials: TW
authors.lastname: Hutchens
mesh_terms: D002138:Calibration; D006801:Humans; D007781:Lactoferrin / Q000737:chemistry; D009841:Oligonucleotides / Q000032:analysis* / Q000138:chemical synthesis; D010848:Picolinic Acids / Q000737:chemistry; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D009841:Oligonucleotides; D010848:Picolinic Acids; C049246:3-hydroxypicolinic acid; D007781:Lactoferrin