Peptide-Based Switching of Polymer Fluorescence in Aqueous phase

The phage display method on water-soluble and commonly used poly-(2-methoxy-5-propyloxysulfonate-1,4-phenylenevinylene) (mpsPPV) were studied. mpsPPV was immobilized using a layer-by-layer (LbL) assembly technique with poly(diallyldimethylammonium chloride) (PDDA) to obtain water-insoluble polyelectrolyte multilayer films, with an outermost surface composed of mpsPPV, on a glass substrate. The assembly process and the stability of the obtained LbL films were monitored by quartz-crystal microbalance (QCM) measurement. A linear 12-mer peptide library solution was applied to this LbL film. The LbL film was considered to be stable throughout the phage display experiment, because the frequency shift was negligible after immersion in ethanol and Tris-buffered saline. It was suggested that π-π interactions were predominant between the peptide and mpsPPV.