LASER INDUCED THERMOSPRAY IONIZATION FOR PM SPECTROMETRY

质谱学电离新技术的发展 以及新的和改进的质谱计设计的发展 在过去的十年里允许大规模和非易失性的增长 要用质谱学技术分析的材料。与生物相关 材料尤其受益于这些进展。脉冲质量 分光计在生物相关性方面特别有吸引力。 材料，因为它们表现出高质量范围。一个潜在的 脉冲质谱计常用的电离方法 TOF-MS尤其是热喷雾技术。由于 连续性质的电离步骤，它目前不是 以脉冲离子源的形式实现。在此建议开发一种 与脉冲兼容的热喷雾电离的变种 质谱仪。这将通过在 溶液与常规热喷涂技术中的方法相同。取而代之的是 直接引入离子源，流出物(微升/分钟)流动 差饷)将作为气雾剂喷洒在旋转的金属滚筒上， 连接到一个变温低温冷头上。流出的水 将被冻结为一条类似理发杆的窄带，因为 收集表面的开塞螺旋运动。此后， 将流出的水旋转成高功率脉冲的聚焦光束 二氧化碳激光器将在脉冲条件下解吸废水和溶剂 举止。在适宜的实验条件下，待测 预计离子将以类似于热喷雾的方式形成 随着膨胀的溶剂团簇蒸发并喷出完整的分子 离子。拟议的电离技术的一个预期的附加优势 它将与微量和毛细管高效液相色谱方法兼容 在样本有限的情况下和在 毛细管液相色谱柱，对混合物有更高的分辨率。

The development of new ionization techniques for mass spectrometry together with developments in new and improved mass spectrometer designs has in the last decade allowed increasing large and non-volatile materials to be analyzed by mass spectrometric techniques. Bio-relevant materials have benefited especially from these advances. Pulsed mass spectrometers are particularly attractive for biologically relevant materials due to the high mass range which they exhibit. A potentially useful ionization method for pulsed mass spectrometers in general and TOF-MS in particular is the thermospray technique. Due to the continuous nature of the ionization step, it is not currently implemented as a pulsed ion source. It is proposed here to develop a variant of thermospray ionization which will be compatible with pulsed mass spectrometers. This will be accomplished by performing ions in solution as is done in the conventional thermospray technique. Instead of direct introduction into the ion source, the effluent (muL/min. flow rates) will be sprayed as an aerosol onto a rotating metal drum which is attached to a variable temperature cryogenic coldhead. The effluent will be frozen out as a narrow band resembling a barber pole due to the corkscrew motion of the collecting surface. Subsequent to this, the effluent will be rotated into the focused beam of a high powered pulsed carbon dioxide laser which will desorb effluent and solvent in a pulsed manner. Under suitable experimental conditions to be determined, it is expected that ions will be formed in an analogous manner to thermospray as the expanding solvent clusters evaporate and eject intact molecular ions. An expected added advantage to the proposed ionization technique will be its compatibility with micro and capillary HPLC methods which should exhibit increased sensitivity for sample limited cases and in the case of capillary HPLC, higher resolving power for mixtures.