Experimental investigations of the internal energy of molecules evaporated via laser-induced acoustic desorption into a Fourier transform ion cyclotron resonance mass spectrometer.
Experimental investigations of the internal energy of molecules evaporated via laser-induced acoustic desorption into a Fourier transform ion cyclotron resonance mass spectrometer.
复制标题
通过激光诱导声解吸进入傅里叶变换离子回旋共振质谱仪蒸发的分子内能的实验研究。
DOI：
10.1021/ac061596x
复制
发表时间：
2007
影响因子：
7.4
通讯作者：
Kenttämaa,HilkkaI
中科院分区：
文献类型：
--
作者：
Shea,RyanC;Petzold,ChristopherJ;Liu,Ji-Ang;Kenttämaa,HilkkaI
中性气相有机和生物分子的内能，蒸发通过激光诱导声解吸（LIAD）到傅立叶变换离子回旋共振质谱仪，通过几种实验方法进行了研究。通过收集LIAD蒸发的分子并通过电喷雾电离/四极杆离子阱质谱法对它们进行分析，证明解吸的分子在解吸过程中不会发生降解。先前建立的气相碱度值重新测量的LIAD蒸发的有机分子和生物分子与使用的括号法。未观察到吸热反应。重新测量的碱度值与文献中报道的值非常一致。在LIAD期间沉积的内能的量被推断为小于每摩尔几千卡。采用一系列质子转移试剂进行化学电离，获得了质子化二肽Val-Pro的击穿曲线。此击穿曲线与先前公布的类似曲线，通过使用基板辅助激光解吸（SALD）蒸发的肽的比较表明，通过LIAD蒸发的分子具有类似的内部能量通过SALD蒸发。
The internal energy of neutral gas-phase organic and biomolecules, evaporated by means of laser-induced acoustic desorption (LIAD) into a Fourier transform ion cyclotron resonance mass spectrometer, was investigated through several experimental approaches. The desorbed molecules were demonstrated not to undergo degradation during the desorption process by collecting LIAD-evaporated molecules and subjecting them to analysis by electrospray ionization/quadrupole ion trap mass spectrometry. Previously established gas-phase basicity values were remeasured for LIAD-evaporated organic molecules and biomolecules with the use of the bracketing method. No endothermic reactions were observed. The remeasured basicity values are in close agreement with the values reported in the literature. The amount of internal energy deposited during LIAD is concluded to be less than a few kilocalories per mole. Chemical ionization with a series of proton-transfer reagents was employed to obtain a breakdown curve for a protonated dipeptide, Val-Pro, evaporated by LIAD. Comparison of this breakdown curve with a previously published analogous curve obtained by using substrate-assisted laser desorption (SALD) to evaporate the peptide suggests that the molecules evaporated via LIAD have a similar internal energy as those evaporated via SALD.