Electrospray sample deposition for matrix-assisted laser desorption/ionization (MALDI) and atmospheric pressure MALDI mass spectrometry with attomole detection limits.
Electrospray sample deposition for matrix-assisted laser desorption/ionization (MALDI) and atmospheric pressure MALDI mass spectrometry with attomole detection limits.
复制标题
用于基质辅助激光解吸/电离 (MALDI) 的电喷雾样品沉积和具有阿托摩尔检测限的大气压 MALDI 质谱分析。
DOI：
10.1002/rcm.1458
复制
发表时间：
2004
期刊：
影响因子：
--
通讯作者：
Kennedy,RobertT
中科院分区：
文献类型：
--
作者：
Wei,Hui;Nolkrantz,Kerstin;Powell,DavidH;Woods,JamesH;Ko,Mei-Chuan;Kennedy,RobertT
研究了电喷雾样品沉积的基质辅助激光解吸/电离飞行时间质谱法（MALDI - TOFMS）。在该方法中，从高压偏置（1-2 kV）熔融石英毛细管中，将纳米体积的基质/分析物混合物电喷涂到距离毛细管出口100-500 μm的接地MALDI板上。在此条件下电喷涂沉积得到的样品光斑直径为200 ~ 300 μm，与激光光斑尺寸相匹配。不同的喷雾电压和距离导致α‐氰基‐4‐羟基肉桂酸基质的晶体大小和挥发速率不同。当样品作为湿滴沉积而不是作为干燥固体沉积时，获得了最好的结果。在湿喷雾条件下，形成直径2-4 μm的晶体，几种神经肽的检出限为0.7-25 amol。样品可以通过连续喷涂在平板上预浓缩，并允许样品在一个小点上蒸发。样品体积高达580 nL，对神经紧张素1‐11的检测限为35 pM。当使用常压MALDI与四极离子阱质谱联用时，电喷雾样品沉积也得到了类似的结果，只是灵敏度差了7倍。版权所有©2004 John Wiley & Sons， Ltd
Electrospray sample deposition was explored for matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOFMS). In this method, nanoliter volumes of matrix/analyte mixture were electrosprayed from a high voltage biased (1–2 kV) fused‐silica capillary onto a grounded MALDI plate mounted 100–500 μm from the capillary outlet. Electrospray deposition with these conditions produced sample spots 200–300 μm in diameter thus matching the laser spot size. Varying spray voltage and distance resulted in different crystal sizes and volatilization rates forα‐cyano‐4‐hydroxycinnamic acid matrix. Best results were obtained when the sample was deposited as wet droplets as opposed to deposition as dried solid. Under ‘wet‐spray’ conditions, 2–4 μm diameter crystals were formed and detection limits for several neuropeptides were 0.7–25 amol. Samples could be pre‐concentrated on the plate by spraying continuously and allowing sample to evaporate in a small spot. Sample volumes as large as 580 nL were deposited yielding a detection limit of 35 pM for neurotensin 1‐11. Electrospray sample deposition yielded similar results when using atmospheric pressure‐MALDI coupled with a quadrupole ion trap mass spectrometer, except that the sensitivity was ∼seven‐fold worse. Copyright © 2004 John Wiley & Sons, Ltd.