Sulfur-functionalized zirconium(IV)-based metal-organic frameworks relieves aggregation-caused quenching effect in efficient electrochemiluminescence sensor

Here, the sulfur-functionalized zirconium(IV)-based metal-organic frameworks (Zr-MOFs) with high luminous efficiency as a novel luminophore was used to construct the electrochemiluminescence (ECL) sensor. Compared to the ligand with the aggregate state as the luminophore, the Zr-MOFs with porous structure could relieve the ECL aggregation-caused quenching (ACQ) effect, resulting in an enhancement of ECL intensity. Impressively, the coreactant tripropylamine came from tripropylamine-modified gold nanoparticles (TPrA@AuNPs) were immobilized on Zr-MOFs to form the composite (TPrA@AuNPs/Zr-MOFs), which could significantly increase the local concentration of the coreactant on the surface of electrode, shorten the electron transport distance between the coreactant and the luminophore, reduce the energy loss during the reaction and further improve the ECL efficiency of the Zr-MOFs/TPrA ECL system. Finally, epinephrine (EP) was selected as model target molecule, the developed biosensor exhibited the linear range from 1.0 x 10(-8) to 1.0 x 10(-2) mol L-1 with a detection limit of 3.3 x 10(-9) mol L-1 (S / N = 3) for EP. This strategy offered a method to improve the ECL efficiency of luminophore for the construction of efficient sensors to detect micromolecule.