电喷雾萃取电离源调节装置的研制

Development of Adjustable Device for Extractive Electrospray Ionization with Improved Performance

电喷雾萃取电离(EESI)源具有样品无需复杂预处理、易于集成和小型化、可与多种商用质谱仪联用、适于现场分析等特点,已在生命科学、环境、食品、国防、刑侦等领域的复杂基体样品的直接质谱分析领域得到了广泛应用。然而,实验室制作的普通EESI源长期稳定性较差,空间位置难以精确调节,针对此问题,本工作研制了EESI源的调节装置。在优化离子源空间位置参数与仪器参数的条件下,安装该调节装置后,采用EESI源对脯氨酸进行检测,检测限由0.5μg/L降至0.075μg/L,并对肺癌患者血样中的缬氨酸、苯丙氨酸、脯氨酸、组氨酸、赖氨酸、天冬酰胺、天冬氨酸、苏氨酸、酪氨酸和谷氨酰胺进行连续5日检测,各样品的平均RSD均小于10%。实验证明,该调节装置具有操作简单、稳定性高、适应范围广等特点,对EESI离子源的性能有较大提高。

Extractive electrospray ionization（EESI） mass spectrometry（MS） has been increasingly used for real time trace analysis of various samples with complex matrices. EESI is easy to be implemented in all types of commercially available MS instruments. However, self-assembled simple EESI source is short of long-term stability. An adjustable device spe- cially developed for EESI source was presented in this work. With parameters of ion source spatial location and MS instrument optimized, the detection limit of EESI using the adjusta- ble device to test proline is reduced from 0. 5μg/L to 0. 075 /μg/L. The representative amino acids, valine, phenylalanine, proline, histidine, lysine, asparagine, aspartic acid, threonine, tyrosine and glutamine in blood samples obtained from patients with lung cancer have been tested continuously for 5 days and the average RSD for each sample is less than 10%. The experimental results show that the newly developed EESI source has been im-proved, particularly on the aspects such as stability, precision and sensitivity.