质谱技术研究儿茶素及儿茶素-锗多聚体特性

采用HPLC-ESI-Q-TOF和MALD I-TOF质谱技术分析儿茶素组成与结构,发现儿茶素中的表没食子儿茶素没食子酸酯(EGCG)具有多聚体特性。有机化学法合成EGCG-Ge4 化合物,并经HPLC进一步分离纯化。红外光谱和质谱技术分析并证实EGCG不仅能形成多聚体,而且还能络合金属锗(包括其他金属离子),成为EGCG-Ge4 和EGCG-Ge4 多聚体。EGCG-Ge4 抑制肺癌细胞生长速率明显高于EGCG,其提高幅度约为30%~40%左右。

Polymer Characteristics of Catechin and Catechin-Ge4+ Measured with a Technology of Mass Spectrometry

The catachin mainly consists of(-)-epigallocatechin(EGC),(-)-epicate-chin(EC),(-)epigallocatechin-3-gallate(EGCG),and(-)-epicatechin-3-gallate(ECG).Using a combined method of high performance liquid chromatography-electrospray ionization-Q-time of flight(HPLCESI-Q-TOF) mass spectrometry(MS),polymer compounds of EGCG in the catachin can be separated and analyed the same(results) were further approved by matrix assisted laser desorption ionization(MALDI)-TOF MS.The EGCG-Ge~(4 ) compounds synthesized by normal organic synthesis were further purified by a rapid reversed phase-HPLC for studying inhibition growth rate of the lung cancer cells.During the analytical process of EGCG-Ge~(4 )(molecular) structures with infrared spectrometry and MALDI-TOF MS,it was found that EGCG not only had polymer characteristics,but also bound to the metal Ge~(4 )(or other heavy metal ions,M~(2 )) for forming EGCG-Ge~(4 )(or EGCG-M~(2 )) and its polymers.The experimental results showed that both EGCG and EGCG-Ge~(4 ) could inhibit the growth rate of lung cancer cells,showing the similar rate within the 24 h for cell incubating.However,this inhibition rate with EGCG-Ge~(4 ) was much higher than that of EGCG,approximately(enhancing) 30%~40% rate for inhibiting growth of lung cancer cells was observed within the incubating time covering from 24 to 72 h.Even so,both compounds cannot inhibit the growth rate of melanoma cells.It(suggest) that the compound EGCG-Ge~(4 ) has potentials for developing new drugs for curing lung cancer.