(235a) Nanostructured Redox Interfaces for Electrochemically-Mediated Bioseparations

Authors: 
Su, X., Massachusetts Institute of Technology
Huebner, J., Massachusetts Institute of Technology
Franzreb, M., Forschungszentrum Karlsruhe GmbH
Jamison, T., Massachusetts Institute of Technology
Hatton, T. A., Massachusetts Institute of Technology
The purification and selective separation of biomolecules is one of the most important steps in modern biochemical industry. Processes based on electrosorption have emerged as a promising candidate in many fields of separation, especially in liquid-phase deionization – however, its application for protein purification has been limited, both due to low adsorption capacity and to selectivity challenges. Redox-active materials are an attractive platform for engineering specific interactions with charged species by electrochemical control.1 Here, we present the advantage of nanostructured, poly(vinyl)ferrocene-based redox-electrodes for the electrosorption and recovery of a range of proteins, with high adsorption capacity and modulated solely by electrochemical potential, thus with no need for chemical regenerants or pH changes.2 Our system was selective for various proteins based on size and charge distribution, exhibiting fast kinetics (<120 s for a charge-discharge cycle) and high uptake capacities (>200 mg/g) under moderate overpotentials (+0.4 V vs Ag/AgCl). Furthermore, the preservation of bioactivity at the surface of electrodes indicates the potential for our systems to to be used as heterogeneous supports for enzyme catalysis. This work draws on the molecular selectivity of ferrocene-functionalized materials towards organic anion groups, and suggests that these smart redox-active materials may possibly be used at-scale for practical bioseparations.

References. (1) Su, X.; Kulik, H. J.; Jamison, T. F.; Hatton, T. A. Advanced Functional Materials 2016, 26, 3394. (2) Su, X.; Hubner, J.; Kauke, M. J.; Dalbosco, D.; Thomas, J.; Gonsalez, C.; Zhu, E.; Franzreb, M.; Jamison, T. F.; Hatton, T. A. Submitted 2017.