title: Prediction of redox potentials of adrenaline and its supramolecular complex with glycine: theoretical and experimental studies.
abstract: Protonated adrenaline (PAd) can be oxidized to protonated adrenaline quinone (PAdquinone) through a one-step, two-electron redox reaction. The electron-transfer property of PAd and its supramolecular complex with glycine has been investigated by cyclic voltammetry (CV) experiment and theoretical calculations. From CV curves, the conditional formal redox potential E°' of PAd/PAdquinone couple at the pH value of 0.29 is determined to be 0.540 V. The calculated E°' using the G3MP2//B3LYP method and the B3LYP method with 6-31G(d,p), 6-31+G(d,p), 6-311G(d,p), and B3LYP/6-311+G(d,p) basis sets are in reasonable agreement with the experimental value. PAd can form supramolecular complex (PAd-Gly) with glycine (Gly) through hydrogen bond (H-bond), and the calculated E°' values of PAd-Gly/PAdquinone-Gly redox couple are larger than those of PAd/PAdquinone couple. The theoretical results are in good agreement with the experimental finding that the formation of H-bonds weaken the electron-donating ability of PAd.
authors: Key Lab of Colloid and Interface Chemistry, Ministry of Education, Institute of Theoretical Chemistry, Shandong University, Jinan 250100, PR China.
authors: Tao
authors: T
authors: Liu
authors: Chunmei
authors: C
authors: Du
authors: Zhangyu
authors: Z
authors: Yu
authors: Lingli
authors: L
authors: Han
authors: Dongju
authors: D
authors: Zhang
mesh_terms: D055664:Electrochemical Techniques; D004566:Electrodes; D004583:Electrons; D004837:Epinephrine / Q000737:chemistry*; D005998:Glycine / Q000737:chemistry*; D006860:Hydrogen Bonding; D006863:Hydrogen-Ion Concentration; D008958:Models, Molecular; D010084:Oxidation-Reduction; D013816:Thermodynamics
chemical_list: D005998:Glycine; D004837:Epinephrine