(373o) Investigation of Superparamagnetic Iron Oxide Nanoparticles (Fe3O4) Coated with Carbonic Anhydrase Embedded On Poly (vinyl alcohol) for Carbon Dioxide (CO2) Separation Process

Authors: 
Lee, J. S., University of wyoming
Johnson, P. A., University of Wyoming


Separation of carbon dioxide (CO2) using enzymes has been studied to fabricate enzymatic magnetite nanoparticles. Carbonic Anhydrase (CA) catalyzes the conversion of CO2 to bicarbonate ions. In the CO2 separation process, the bicarbonate anion could be coupled with a positively charged ion to form bicarbonate salts or reacted by other enzymes to form hydrocarbon products. Nanostructured materials for capturing CO2 were investigated in three steps. (1) Magnetic nanoparticles (Fe3O4) were fabricated by a co-precipitation method and by a sonochemical approach. (2) Magnetic nanoparticles (PVA-MNPs) coated by poly (vinyl alcohol) were synthesized. PVA is a biocompatible and polycationic polymer. (3) Enzymes immobilized on magnetic materials (CA-PVA-MNPs) were fabricated. The synthesized magnetite nanoparticles were characterized by Fourier Transform Infrared Spectrometry (FT-IR), Differential Scanning Calorimetry (DSC), Thermogravimetric analysis (TGA), and Vibrating Sample Magnetometer (VSM) to confirm the PVA coating on Fe3O4 and the binding of carbonic anhydrase to PVA. Morphology of the synthesized magnetite particles was studied by Transmission Electron Microscopy (TEM). Particle size and aggregation state were characterized by zeta-potential measurements, Dynamic Light Scattering (DLS), and UV-Vis Spectroscopy. For the CO2 separation process, enzyme activity tests were conducted comparing pure enzymes to PVA thin films as well as CA-PVA-MNPs. Effects of pH on the substrate and enzyme reaction in aqueous solution were studied in order to find a optimal the CO2 capturing conditions.