Effects of substitute group, axial ligand and volatile organic compounds on binding ability of colorimetric sensor array

Abstract

Cobalt porphyrin and similar metalloporphyrins (MPs) were initially used in the colorimetric sensor array (CSA) system for quality assurance and quality control in beverage and food. In order to design a proper CSA sensor, density functional theory method with B3LYP/LANL2DZ basis set was performed to investigate the influences of axial ligand, substituent group and volatile organic compounds (VOCs) on the binding process. Ground state structure was determined at three spin states: low, intermediate and high spin states, based on the relative energy. The binding energy (BE) for each MP model was obtained by differentiating the energy of MP before and after binding with VOCs. The binding ability of MPs and their complexes can be divided into three classes based on the BE. This theoretical research would be used for the further design of CSA sensor to extend the application of CSA.