On-line microdialysis sample cleanup for electrospray ionization mass spectrometry of nucleic acid samples

Journal Article · Sun Sep 15 04:00:00 EDT 1996 · Analytical Chemistry (Washington)

DOI:https://doi.org/10.1021/ac960286j· OSTI ID:420884

Liu, C; Wu, Q; Harms, A C; Smith, R D ^[1]

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1. Pacific Northwest National Lab., Richland, WA (United States)

A major limitation of electrospray ionization mass spectrometry (ESI-MS) for oligonucleotide analysis arises due to sodium adduction, a problem that increases with molecular weight. Sodium adduction can preclude useful measurements when limited sample sizes prevent off-line cleanup. A novel and generally useful on-line microdialysis technique is described for the rapid (nearly 1-5 min) DNA sample cleanup for ESI-MS. Mass spectra of oligonucleotides of different size and sequence showing no significant sodium adduct peaks were obtained using the on-line microdialysis system with sodium chloride concentrations as high as 250 mM. Signal-to-noise ratios were also greatly enhanced compared to direct infusion of the original samples. By using ammonium acetate as the dialysis buffer, it was also found that the noncovalent association of double-stranded oligonucleotides could be preserved during the microdialysis process, allowing analysis by ESI-MS. 33 refs., 6 figs.

• DOE Contract Number: AC06-76RL01830
• OSTI ID: 420884
• Journal Information: Analytical Chemistry (Washington), Journal Name: Analytical Chemistry (Washington) Journal Issue: 18 Vol. 68; ISSN ANCHAM; ISSN 0003-2700
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
ACETATES
AMMONIUM COMPOUNDS
BUFFERS
DIALYSIS
IONIZATION
MASS SPECTRA
MASS SPECTROSCOPY
MICROANALYSIS
NUCLEIC ACIDS
QUANTITATIVE CHEMICAL ANALYSIS
SAMPLE PREPARATION
SIGNAL-TO-NOISE RATIO