Designing the Selectivity of the Fluorescent Detection of Amino Acids:  A Chemosensing Ensemble for Histidine

Abstract

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) receptor.

Design of fluorescent materials for chemical sensing

“…The third strategy is called chemosensing ensemble, based on a competitive assay in which a receptor-fluorophore ensemble is selectively dissociated by the addition of an appropriate competitive analyte able to interact efficiently with the receptor resulting in a detectable response of the fluorophore. [36][37][38][39][40] 3 Fluorescent materials for chemical sensing…”

Colorimetric Sensor Design

“…Although this provides increased sensitivity, it may decrease selectivity. An example of this was provided by Fabbrizzi and coworkers, who showed that they could tailor the selectivity of their receptor by choosing different indicators [42,43]. Another consideration is choosing a dye that shows a significant color change when displaced from its microenvironment into the bulk solution.…”

Zn(II) Coordination by Open-chain Polyamine Ligands Containing Dipyridine Units. Highly Active Dinuclear Zn(II) Complexes in Phosphate Ester Hydrolysis

“…Polyamine ligands containing six or more nitrogen donors and cavities of appropriate shape and dimension may be able to hold two metal centers at short distances [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29]. The distance between the two metal ions can be varied by an opportune synthetic modulation of the structural characteristics of the ligands.…”