The imidazole group of histidine deprotonates and bridges the two CuII centers of a dimetallic polyamine macrocyclic complex, displacing the previously bound and quenched fluorescent indicator I. Thus, histidine recognition is signaled by the revival of the fluorescence of I. Selectivity with respect to other natural amino acids is achieved by choosing an indicator of tuned affinity toward the dicopper(II)
组氨酸的咪唑基团去质子化并桥接双金属多胺大环复合物的两个 CuII 中心,取代先前结合和淬灭的荧光指示剂 I。因此,组氨酸识别通过 I 的荧光恢复发出信号。相对于其他天然物质的选择性氨基酸是通过选择对二铜 (II) 受体调节亲和力的指标来实现的。