Identification of peptides for the surface functionalization of perovskite ferroelectrics

Combinatorial phage display methods have been used to identify a heptapeptide sequence, ISLLHST, that strongly associates with a perovskite ferroelectric, Pb (Zrx Ti1-x) O3 (PZT). The selectively of peptide binding to polycrystalline metalorganic chemical vapor deposition deposited PZT thin films were determined by titering and immunofluorescence microscopy. Ferroelectric properties were determined by measurement of the P-E hysteresis loop on unmodified and phage bound PZT thin films. No change in the coercive field, Ec, or the saturation polarization, Ps was observed. The remnant polarization, PR, however, showed a minor reduction after exposure to aqueous buffer and/or phage binding, possibly due to association of compensating surface charges on the PZT.