Smith David, Wang Tianshu, Spanĕl Patrik
Centre for Science and Technology in Medicine, School of Medicine, Keele University, Thornburrow Drive, Hartshill, Stoke-on-Trent ST4 7QB, UK.
Rapid Commun Mass Spectrom. 2003;17(23):2655-60. doi: 10.1002/rcm.1244.
A selected ion flow tube mass spectrometry (SIFT-MS) study of the reactions of H3O+, NO+ and O2+* ions with the ketones (M) 2-heptanone, 2-octanone, 2-nonanone, 2-undecanone and 2-aminoacetophenone has been conducted in preparation for studies of volatile emissions from bacteria. The H3O+ reactions all proceed rapidly via exothermic proton transfer, producing only MH+ ions that form their monohydrates when water vapour is present in the helium carrier gas. The O2+* reactions proceed rapidly via dissociative charge transfer producing parent cations M+* and some fragment ions. The NO+ reactions form the NO+M adduct ions at rates which are dependent on the pressure of the helium carrier gas. Combining the present NO+ kinetic data with those available from previous SIFT studies, the phenomenon of charge transfer complexing is clearly demonstrated. This results in adduct formation in these NO+/ketone reactions at or near the collisional rate. SIFT-MS spectra are presented to illustrate the simplicity of SIFT-MS analysis of ketones using both H3O+ and NO+ precursor ions.
为了开展对细菌挥发性排放物的研究，已经进行了一项选择离子流管质谱法（SIFT-MS）研究，研究对象是H3O+、NO+和O2+*离子与酮类物质（M）（2-庚酮、2-辛酮、2-壬酮、2-十一烷酮和2-氨基苯乙酮）之间的反应。H3O+反应均通过放热质子转移迅速发生，仅产生MH+离子，当氦载气中存在水蒸气时，这些离子会形成它们的一水合物。O2+*反应通过离解电荷转移迅速进行，产生母体阳离子M+*和一些碎片离子。NO+反应以取决于氦载气压力的速率形成NO+M加合离子。将当前的NO+动力学数据与先前SIFT研究中可得的数据相结合，电荷转移络合现象得到了清晰的证明。这导致在这些NO+/酮反应中以碰撞速率或接近碰撞速率形成加合物。给出了SIFT-MS光谱，以说明使用H3O+和NO+前体离子对酮进行SIFT-MS分析的简便性。
