Competitive adsorption and selective sensing of dopamine over epinephrine and norepinephrine on MOF copper seed composite-based probe

Abstract

The reticular hydrothermal technique was employed in the fabrication of Zn-based MOFs. The synthesis of MOFCu seed has been accomplished from Zn-MOF-CuCl-OLA (oleyl amine) through the solvothermal method. The crystalline defects were diminished by copper seeds, thereby improving the electrochemical selectivity towards dopamine (DA). The MOF-Cu-GCE exhibited more virtuous selectivity for DA over epinephrine (EP), norepinephrine (NE), and other chemical analogs and inorganic salts. This unique selectivity is ascribed to the exterior modification of Cu0 to boost the adsorption of DA onto MOF-Cu-GCE through soft -soft interaction and aromatic functionality. Quantitative sensing of dopamine by MOF-Cu-GCE was achieved in the linear range of 50-1100 nM in HSA-PBS with a detection limit of 9.28 nM. Also, the MOF-Cu-GCE demonstrated excellent stability and reproducibility. This research work is a footing for the emergence of a probe for DA based on the hard -soft acidbase principle (HSAB).