Development of a polymer/TiO2 hybrid two-dimensional photonic crystal for highly sensitive fluorescence-based ion sensing applications

By using a fluorescent dye-containing polymer (poly(methyl methacrylate), PMMA) for the fabrication of the polymer/TiO2 hybrid PhC, the fluorescence intensity was drastically (25 times) increased. Subsequently, we used an ion-sensing polymer composed of plasticized poly(vinyl chloride) (PVC), a fluorescent dye, and ion recognition elements in the polymer/TiO2 hybrid PhC to enable its use as a highly sensitive ion sensor. As a result, the ion sensor based on the plasticized-PVC/TiO2 hybrid PhC exhibited four times greater fluorescence intensity compared with that based on the plasticized PVC without the PhC structure.