化学合成十三肽及其副产物液质联用分析

利用反相高效液相色谱(RP-hplc)与电喷雾质谱(ESI-MS和MS/MS)联用技术直接分析用芴甲氧羰基(Fmoc)固相多肽合成方法手工偶联合成的一个十三肽(Lys-Lys-Glu-Ser-Asp-Phe-Leu-Met-Phe-Val-Tyr-Leu-Val，Mr 1617．8)粗产品，以探索RP-HPLC/ESI-MS和MS/MS在固相多肽合成产物分析和副反应机制研究中的应用．RP-HPLC结果显示：合成粗产物中含有1个主成分，2个次要成分和多个微量成分；与之联用的电喷雾质谱同步准确地测定出各成分的相对分子质量(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十三肽，另外几个主要副产物为十三肽的残缺肽或氧化肽．对色谱和生物质谱联用技术分析合成多肽的意义和副产物形成的可能机制进行了讨论．

Analysis of Crude Synthetic Product of a Tridecapeptide by RP-HPLC/ESI-MS and MS/MS

By using reverse-phase high performance liquid chromatography (RP-HPLC)/ion trap electrospray mass spectrometry(ESI-MS), the main product and the side products of solid phase synthesis of the tridecapeptide were investigated. One major component, two minor components and several trace-level components were detected on the HPLC chromatogram. The accurate molecular weights of each components were determined. The amine acid sequences of the main components were analyzed by tandem mass spectrometry (MS/MS) synchronously. The results showed that the major component of the crude product was the desired tridecapeptide and the main by-products were derived from the oxidation or deformity of the desired peptide. The significance of the application of biological mass spectrometry coupled with HPLC to synthetic peptide analysis and the possible origins of the by-products were discussed.