Tapered-tip Capillary Electrophoresis Nano-electrospray Ionization Mass Spectrometry for Ultrasensitive Proteomics: The Mouse Cortex

We have enabled ultrasensitive proteomics of limited protein digests by developing a tapered-tip nanoelectrospray ionization (nanoESI) interface for microanalytical capillary electrophoresis (CE) high resolution mass spectrometry (HRMS). CE-nanoESI-HRMS allowed us to detect 260 zmol angiotensin II (lower limit of detection) and identify 1 pg of bovine serum albumin and cytochrome c. A 1 ng protein digest from the mouse posterior cortex yielded 217 nonredundant protein groups, including many gene products that are used as classical neuronal markers.

本研究开发了用于微分析毛细管电泳（capillary electrophoresis，CE）高分辨质谱（high resolution mass spectrometry，HRMS）的锥尖型纳米电喷雾电离（nanoelectrospray ionization，nanoESI）接口，借此实现了对有限量蛋白质酶解物的超灵敏蛋白质组学分析。该CE-nanoESI-HRMS联用技术可实现260仄摩尔血管紧张素II的检出（最低检出限），并可鉴定1皮克级的牛血清白蛋白与细胞色素c。对小鼠后皮层的1纳克蛋白质酶解物进行分析时，共鉴定得到217个非冗余蛋白质组，其中包含诸多用作经典神经元标志物的基因编码产物。