title: High-throughput biopolymer desalting by solid-phase extraction prior to mass spectrometric analysis.
abstract: In the last 10 years mass spectrometry (MS) has become an important method for analysis of peptides, proteins and DNA. It was recently utilized for accurate high-throughput protein identification, sequencing and DNA genotyping. The presence of non-volatile buffers compromises sensitivity and accuracy of MS biopolymer analysis; it is essential to remove sample contaminants prior to analysis. We have developed a fast and efficient method for desalting of DNA oligonucleotides and peptides using 96-well solid-phase extraction plates packed with 5 mg of Waters Oasis HLB sorbent (Waters, Milford, MA, USA). This reversed-phase sorbent retains the biopolymer analytes, while non-retained inorganic ions are washed out with pure deionized water. DNA oligonucleotides or peptides are eluted using a small amount (20-100 microl) of acetonitrile-water (70:30, v/v) solution. The SPE desalting performance meets the requirements for MS applications such as protein digest analysis and DNA genotyping.
authors.affiliation: Waters Corporation, Milford, MA 01757-3696, USA. martin_gilar@waters.com
authors.forename: M
authors.initials: M
authors.lastname: Gilar
authors.forename: A
authors.initials: A
authors.lastname: Belenky
authors.forename: B H
authors.initials: BH
authors.lastname: Wang
mesh_terms: D001704:Biopolymers / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D003574:Cytochrome c Group / Q000737:chemistry; D004247:DNA / Q000302:isolation & purification*; D010449:Peptide Mapping; D012492:Salts; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
chemical_list: D001704:Biopolymers; D003574:Cytochrome c Group; D012492:Salts; D004247:DNA