海洋硫酸多糖911的荧光标记研究

硫酸多糖（911）的性末端的半缩醛基,通过还原胺化反应与酪胺（Tyr)的氨基共价偶联,911－Tyr中酪胺引入的仲氨基通过与异硫氰酸酯荧光素（FITC）进行亲核反应,实现对911还原末端的选择性荧光标记。用UV－Vis吸收光谱,^1H NMR和HPSEC对偶联与标记结果进行确证,从^1H NMR谱推测911与酪胺的偶联率及FITC为911－Tyr标记率分别为60％和80％。由于采用的是911末端选择性标记,对911的抗凝活性无明显影响,也无明显细胞的毒性。以荧光标记的911作为探针,对淋巴细胞有较强的选择性标记染色。该法适用于具有还原末端的多糖及寡糖的荧光标记。

Studies on Fluorescent Labeling of Marine Sulfated Polysaccharide 911

The reducing terminal of marine sulfated polysaccharide(911) was used to selectively insert primary and secondary amines by reductive amination. 911 was bounded to 4\|(2\|aminoethylphenol), followed by labeling the 911\|Tyr with fluorescein\|5\|isothiocyanate(FITC) at the secondary amino group. High\|performance size\|exclusion chromatography(HPSEC), ultraviolet/visible(UV\|Vis) spectroscopy and nuclear magnetic resonance spectroscopy(NMR) demonstrated the binding of tyramine to 911 and the labeling of FITC to 911\|Tyr respectively. Furthermore, \{\}\+1H NMR spectra and UV\|Vis spectra revealed about 60% binding of tyramine to 911 and about 80% labeling of FITC to 911\|Tyr. The anticoagulant activity of labeled fluorescent compound exhibited 13.40 U/mg equivalent to that of unlabled 911. In addition, the labeled compound was demonstrated to fluorescently stain lymphocytes without any cytotoxity. Taken together, the selectively "end point attached" method might be widely used for fluorecent labeling to those polysaccharides with reducing terminal.