Barlow Christopher K, Hodges Brittany D M, Xia Yu, O'Hair Richard A J, McLuckey Scott A
School of Chemistry, University of Melbourne, Melbourne, Australia.
J Am Soc Mass Spectrom. 2008 Feb;19(2):281-93. doi: 10.1016/j.jasms.2007.10.017. Epub 2007 Nov 1.
Multiply deprotonated hexadeoxyadenylate anions, (A6-nH)(n-), where n = 3-5, have been subjected to reaction with a range of divalent transition-metal complex cations in the gas phase. The cations studied included the bis- and tris-1,10-phenanthroline complexes of CuII, FeII, and CoII, as well as the tris-1,10-phenanthroline complex of RuII. In addition, the hexadeoxyadenylate anions were subjected to reaction with the singly charged FeIII and CoIIIN,N'-ethylenebis(salicylideneiminato) complexes. The major competing reaction channels are electron-transfer from the oligodeoxynucleotide anion to the cation, the formation of a complex between the anion and cation, and the incorporation of the transition-metal into the oligodeoxynucleotide. The latter process proceeds via the anion/cation complex and involves displacement of the ligand(s) in the transition-metal complex by the oligodeoxynucleotide. Competition between the various reaction channels is governed by the identity of the transition-metal cation, the coordination environment of the metal complex, and the oligodeoxynucleotide charge state. In the case of the divalent metal phenanthroline complexes, competition between electron-transfer and metal ion incorporation is particularly sensitive to the coordination number of the reagent metal complexes. Both electron-transfer and metal ion incorporation occur to significant extents with the bis-phenanthroline ions, whereas the tris-phenanthroline ions react predominantly by metal ion incorporation. To our knowledge this work reports the first observations of the gas-phase incorporation of multivalent transition-metal cations into oligodeoxynucleotide anions and represents a means for the selective incorporation of transition-metal counter-ions into gaseous oligodeoxynucleotides.
多去质子化的十六聚脱氧腺苷酸阴离子（A6-nH）(n-)，其中n = 3 - 5，已在气相中与一系列二价过渡金属络合阳离子发生反应。所研究的阳离子包括CuII、FeII和CoII的双-和三-1,10-菲咯啉络合物，以及RuII的三-1,10-菲咯啉络合物。此外，十六聚脱氧腺苷酸阴离子还与单电荷的FeIII和CoIIIN,N'-亚乙基双（水杨醛亚胺基）络合物发生反应。主要的竞争反应通道是从寡脱氧核苷酸阴离子到阳离子的电子转移、阴离子与阳离子之间形成络合物以及过渡金属掺入寡脱氧核苷酸中。后一过程通过阴离子/阳离子络合物进行，涉及寡脱氧核苷酸取代过渡金属络合物中的配体。各种反应通道之间的竞争取决于过渡金属阳离子的特性、金属络合物的配位环境以及寡脱氧核苷酸的电荷状态。对于二价金属菲咯啉络合物，电子转移和金属离子掺入之间的竞争对试剂金属络合物的配位数特别敏感。双菲咯啉离子的电子转移和金属离子掺入都有显著程度的发生，而三菲咯啉离子主要通过金属离子掺入进行反应。据我们所知，这项工作首次报道了多价过渡金属阳离子气相掺入寡脱氧核苷酸阴离子的观察结果，并且代表了一种将过渡金属抗衡离子选择性掺入气态寡脱氧核苷酸的方法。
