Bieniarz C, Husain M, Barnes G, King C A, Welch C J
Department of Immunochemistry, Abbott Laboratories, North Chicago, Illinois 60064, USA.
Bioconjug Chem. 1996 Jan-Feb;7(1):88-95. doi: 10.1021/bc950080+.
A series of extended length heterobifunctional coupling agents is described. The successive aminocaproic acid homologation of succinimidyl 4-(N-maleimidomethyl)cyclohexane-1-carboxylate, a known 9-atom long maleimide active ester linker, yielded 16-, 23-, and 30-atom long maleimide active ester homologues. The performance study of these coupling agents in automated microparticle enzyme immunoassays showed that, in the alpha fetoprotein assay, in which the linkers were employed in the construction of the alkaline phosphatase-antibody conjugates, the signal increased 64% when the length of the linker was incremented from 9 atoms to 23 atoms and 82% for the 30-atom long linker as compared with the 9-atom homologue. Similar improvements were observed in the performance of carbohydrate antigen, marker of ovarian cancer (CA-125), immunoassay where the linkers were used for conjugation of the capture antibody anti-CA-125 to the microparticle. Thus, a 300% signal improvement resulted when a 30-atom linker was used instead of the 9-atom homologue. The observed differences in the performance of the conjugates are interpreted as resulting from improved antibody binding and lowering of the steric hindrance of the complementarity-determined region of the antibody when longer coupling agents were used.
描述了一系列延长长度的异双功能偶联剂。已知的9原子长的马来酰亚胺活性酯连接体4-(N-马来酰亚胺甲基)环己烷-1-羧酸琥珀酰亚胺酯经连续的氨基己酸同系化反应，得到了16原子、23原子和30原子长的马来酰亚胺活性酯同系物。这些偶联剂在自动微粒酶免疫测定中的性能研究表明，在甲胎蛋白测定中，当连接体用于构建碱性磷酸酶-抗体缀合物时，与9原子同系物相比，连接体长度从9原子增加到23原子时信号增加了64%，对于30原子长的连接体信号增加了82%。在糖类抗原、卵巢癌标志物（CA-125）免疫测定中也观察到类似的性能改善，其中连接体用于将抗CA-125捕获抗体与微粒偶联。因此，当使用30原子连接体而不是9原子同系物时，信号提高了300%。观察到的缀合物性能差异被解释为是由于使用更长的偶联剂时抗体结合改善以及抗体互补决定区的空间位阻降低所致。
