Xia Shifei, Zhang Lan, Qiu Bin, Lu Minghua, Chi Yuwu, Chen Guonan
Department of Chemistry, Fuzhou University, Fuzhou, Fujian 350002, China.
Rapid Commun Mass Spectrom. 2008 Dec;22(23):3719-26. doi: 10.1002/rcm.3787.
A new approach was described to achieve very sensitive analysis of peptide hormone of brain and intestine by capillary electrophoresis coupled with a transient isotachophoresis (tITP) preconcentration method. The system used was electrospray ionization mass spectrometry (ESI-MS) as detector and equipped with a sheath flow configuration. The effects of sample matrix, pH and concentration of leading electrolyte (LE), sample injection time, and ESI-MS instrumental parameters on the efficiency of the sample stacking were investigated in detail. Under the optimized conditions, lower than micromole (0.01 microM) concentrations of the peptides were easily detected. Compared to traditional hydrodynamic injection methods, about 40-230-fold increase in detection sensitivity was obtained by this technique. A distinguishing feature of the described approach is that the background electrolyte can serve as terminating electrolyte (TE), which simplifies the process of the experiments. The method was further evaluated by the analysis of low concentration active peptide mixtures spiked in hypothalamus tissue of the rat.
描述了一种新方法，通过毛细管电泳结合瞬态等速电泳（tITP）预浓缩方法，实现对脑和肠道中肽类激素的非常灵敏的分析。所使用的系统是以电喷雾电离质谱（ESI-MS）作为检测器，并配备鞘流配置。详细研究了样品基质、前导电解质（LE）的pH值和浓度、样品进样时间以及ESI-MS仪器参数对样品堆积效率的影响。在优化条件下，低于微摩尔（0.01 microM）浓度的肽很容易被检测到。与传统的流体动力进样方法相比，该技术的检测灵敏度提高了约40-230倍。所描述方法的一个显著特点是背景电解质可以用作终止电解质（TE），这简化了实验过程。通过分析添加到大鼠下丘脑组织中的低浓度活性肽混合物，对该方法进行了进一步评估。
