Zhu Y, He L, Srinivasan J R, Lubman D M
Department of Chemistry, University of Michigan, Ann Arbor 48109-1055, USA.
Rapid Commun Mass Spectrom. 1997;11(9):987-92. doi: 10.1002/(SICI)1097-0231(19970615)11:9<987::AID-RCM949>3.0.CO;2-J.
Pulsed-delayed extraction using a simple high voltage transistor switch together with various sample purification approaches were used to enhance the resolution in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) of oligonucleotides up to 60 bases long. This switch can provide a 0-3 kV voltage pulse with a 75 ns fall time. A resolution of 500-900 was typically observed for samples from 5-mers to 60-mers using pulsed-delayed extraction (PDE) with the switch described herein. The resolution deteriorated to < 100 for oligonucleotides of > or = 65-mers. With the TOF acceleration region configuration used in this work, the resolution was found not to vary significantly over a delay range of 2-5 mus. As the DNA size increased to over 35-mer, HPLC purification was required to retain the enhancement in resolution provided by PDE MALDI-MS.
使用一个简单的高压晶体管开关结合各种样品纯化方法进行脉冲延迟提取，以提高基质辅助激光解吸/电离飞行时间质谱（MALDI-TOFMS）对长达60个碱基的寡核苷酸的分辨率。该开关可提供一个下降时间为75纳秒的0-3 kV电压脉冲。使用本文所述的开关进行脉冲延迟提取（PDE）时，对于5聚体至60聚体的样品，通常观察到分辨率为500-900。对于65聚体及以上的寡核苷酸，分辨率降至<100。在本工作中使用的TOF加速区域配置下，发现在2-5微秒的延迟范围内分辨率没有显著变化。随着DNA大小增加到超过35聚体，需要进行HPLC纯化以保持PDE MALDI-MS提供的分辨率增强。
