反相高效液相色谱/电喷雾质谱法分析化学合成七肽粗产物

利用RP—HPLC／ESI—MS直接分析用芴甲氧羰基(Fmoc)固相多肽合成方法在PHB树脂上偶联合成的一个七肽(H2N—Tyr—Val—Asn-Thr-Asn—Met—Gly—COOH，Mr797．3)粗产物。RP—HPLC显示合成粗产物含有1个主成分，4个次要成分和多个微量成分；与之联用的电喷雾质谱则同步准确地测定出各成分的分子量(m／z)并自动对各主要成分的化学结构进行了串联质谱分析。结果证明，粗产物中的主成分即为目标七肽，另外几个主要副产物为七肽的氧化产物或残缺肽。

Analysis of Crude Synthetic Product of a Heptapeptide by Reversed Phase High Performance Liquid Chromatography/Electrospray-Mass Spectrometry

In order to investigate the application of reversed-phase high performance liquid chromatography(RP-HPLC)/ion trap electrospray mass spectrometry (ESI-MS)to the solid-phase chemically synthesized peptides and the mechanism of side reactions, RP-HPLC/ESI-MS was applied to the direct analysis of a crude product of heptapeptide (H 2N-Tyr-Val-Asn-Thr-Asn-Met-Gly-CO0H,Mr 797.3) solid-phase chemically synthesized in stepwise fashion using Fmoc chemistry on a PHB resin manually. RP-HPLC showed that the crude product contained one major component, four minor components and several trace-level components. The accurate molecular weight of each component was determined by the coupled electrospray mass spectrometry and the structural analysis of the main components was done by tandem mass spectrometry (MS/MS) synchronously . The results show that the major component of the crude product is the desired heptapeptide and the main by-products are derived from the oxidation or deformity of the desired peptide.