N-去甲万古霉素亲和吸附剂的合成及性能

Synthesis and Characterization of Affinity Adsorbents for N-Demethylvancomycin

将N ,N 二甲基丙烯酰胺 N ,N′ 乙撑双丙烯酰胺共聚物部分水解 ,在共聚物中引入适量的羧基 .含羧基的聚合物与氨基酸甲酯缩合 ,然后使酯基皂化 ,将氨基酸引入聚合物 .将革兰氏阳性菌细胞壁粘肽的三种类似物 (—Gly ,—Gly—D Ala ,—Gly—D Ala—D Ala)分别引入上述聚合物 ,合成了 3种万古霉素系列抗菌素的亲和吸附剂 (Ⅰ ,Ⅱ和Ⅲ ) .结果表明 ,吸附剂Ⅱ和吸附剂Ⅲ对N 去甲万古霉素的吸附量分别为 0 .80和 0 .86mmol/ g;最佳吸附pH值为 6左右 ;吸附剂Ⅰ的吸附量随着吸附液中盐浓度的增加而显著降低 ,而吸附液中盐浓度对吸附剂Ⅱ的吸附量影响较小 .说明亲和作用在吸附剂Ⅱ的吸附中贡献较大 .用 0 .4mol/LNa2 CO3(pH 9.5 ) /CH3CN(体积比为 7/ 3)作为洗脱剂可完全脱附被吸附的N 去甲万古霉素 .

Copolymer of N,N-dimethylacrylamide and N,N′-ethylene bisacrylamide was partially hydrolyzed to introduce the carboxyl groups onto the copolymer. Amino acids were introduced onto the carboxyl group-containing copolymer by coupling the methyl ester of the amino acids with the copolymer and then saponifying the ester. In this way, three analogues(—Gly, —Gly-D-Ala, —Gly—D-Ala—D-Ala) of the cell wall mucopeptide of Gram-positive bacteria were introduced onto the copolymer and three affinity adsorbents (Adsorbents Ⅰ, Ⅱ and Ⅲ) for vancomycin group of antibiotics were synthesized. The results showed that the adsorption capacities of adsorbents Ⅱ and Ⅲ for N-demethylvancomycin were 0. 80 and 0.86 mmol/g, respectively. The optimal pH for the adsorption was about 6. The effect of the salt(NaCl) concentration in the solution on the adsorption capacities of adsorbents Ⅰ and Ⅱ indicated that the capacity of adsorbent Ⅰ decreased markedly with increasing the salt concentration, while the effect of the salt concentration on the capacity of adsorbent Ⅱ was relatively slight. The result suggested that the affinity interaction contributed to the adsorption of adsorbent Ⅱ was greater than that of adsorbent Ⅰ. The adsorbed N-demethylvancomycin was completely desorbed by 0.4 mol/L Na_2CO_3(pH 9.5)/CH_3CN(7/3 in volume ratio).