Hayashi N, Suzuki M, Titani K, Taniguchi H
Division of Biomedical Polymer Science, Fujita Health University, Aichi, Japan.
Nucleic Acids Symp Ser. 1995(34):153-4.
Capillary high performance liquid chromatography/ electrospray mass spectrometry (LC/ ESI/MS) was applied to studies of nucleic acids. Since the presence of salt adducts obscures the molecular peaks and hinders the precise determination of molecular mass, conditions were sought in which effective online desalting and efficient ionization could be achieved simultaneously. In the presence of triethylamine, which is routinely used for the reversed-phase separation of nucleic acid, small oligo-nucleotides could be measured satisfactorily, while RNA tended to show more pronounced adduct peaks. When tributylamine was used instead of the shorter analogue, the adduct peak formation was well suppressed, and the hydrophobic nature of the counter ion made the nucleotides binding to the column tighter, resulting in the better chromatographic separation. The efficient ionization and suppression of the ion adducts make it possible to determine precisely the molecular mass of large nucleotides such as tRNA.
毛细管高效液相色谱/电喷雾质谱法（LC/ESI/MS）被应用于核酸研究。由于盐加合物的存在会掩盖分子峰并阻碍分子量的精确测定，因此需要寻找能够同时实现有效在线脱盐和高效电离的条件。在常规用于核酸反相分离的三乙胺存在下，可以令人满意地测量小的寡核苷酸，而RNA往往显示出更明显的加合物峰。当使用三丁胺代替较短的类似物时，加合物峰的形成得到了很好的抑制，并且抗衡离子的疏水性使核苷酸与柱的结合更紧密，从而实现了更好的色谱分离。高效的电离和离子加合物的抑制使得精确测定诸如tRNA等大核苷酸的分子量成为可能。
