Neutralization of negatively charged oligonucleotides

✍ Scribed by R.B. Jones; S.L. Allman; K. Tang; W.R. Garrett; C.H. Chen

• Book ID: 103035159
• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 589 KB
• Volume: 212
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(93)87227-t

✦ Synopsis

Negative ions of small oligonucleotides are shown to undergo collisional and collision-free neutralization following matrix assisted laser desorption and ionization (MALDI). Using a modified MALDI time of flight instrument, approximate collisional cross sections and collision-free lifetimes have been measured for negative ions of 3-, 4-, 6-and 'I-mer oligonucleotides. Collisional cross sections were on the order of lo-l4 cm2, with collision-free lifetimes on the order of IO-100 pa The evidence suggests that the collision-free lifetime may be decreasing with increasing biopolymer size. Implications of this neutralization process on MALDI-TOF experiments and TOF based DNA sequencing schemes are also discussed.