Application of High Performance Liquid Chromatography/Mass Spectrometry with Electrospray Ionization to the Detection of DNA Nucleosides in Ancient Seeds

✍ Scribed by Kerry O'Donoghue; Terence A. Brown; James F. Carter; Richard P. Evershed

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 457 KB
• Volume: 10
• Category: Article
• ISSN: 0951-4198
• DOI: 10.1002/(sici)1097-0231(19960331)10:5<495::aid-rcm492>3.0.co;2-d

✦ Synopsis

Liquid chromatographylmass spectrometry (LC/MS) with eleetrospray ionization has been used to analyse the nucleoside components of DNA extracted from preserved plant remains. Optimum results were obtained by use of an isOeratic ammonium acetate/acetonitrile mobile phase with post-column addition of 50% v/v aqueous formic acid. Authentic DNA nucleosides gave simple spectra displaying protonated molecular ions, [ M + q + , and base ions, [BH,]+, carrying the bulk of the ion current. Selected ion monitoring (SIM) of these charactenlstic ions was employed to screen for the presence of deoxyrihnuclmides in enzymatic hydrolysates of DNA Isolated from ancient seeds. This use of mass chromatography with co-injection analyses confirmed the presence of 2'deoxycytidine, 2'-deoxyadenosine and 2'-deoxyguanosine in 1400 year-old desiccated radisb ( h p h u s sativtrs) and barley (Hordeurn sp.) seeds. Detection of thymidhe codd not be confirmed due to a low response of this nucleoside under the ionization conditions used. The use of LC/MS-SIM overcomes problems of low volatility and co-eluting contaminants previously seen with GC/MS-SIM of DNA from andent seeds.