Publications by authors named "Ryoutarou Oishi"

Ionophore-based dye liquid nanoemulsion sensors exhibiting rapid response, high selectivity, and high sensitivity to chloride were developed. Since nanoemulsions contain extremely high concentrations of dyes and have large surface areas, rapid and highly sensitive measurements were possible. H-NMR measurements revealed intermolecular interactions between the dye and the ionophore, which contributed to the suppression of the background signal.

View Article and Find Full Text PDF

An enzyme-responsive fluorescent nanoemulsion (NE) based on lipophilic dye liquid (LDL) was developed for alkaline phosphatase (ALP). The response mechanism of the NE involved enzymatic reactions and simultaneous extraction of anions. The LDL-based NE exhibited 3.

View Article and Find Full Text PDF

An ionic liquid-based thin (~ 1 µm) colorimetric membrane (CM) is a key nano-tool for optical ion sensing, and a two-dimensional photonic crystal slab (PCS) is an important nano-platform for ultimate light control. For highly sensitive optical ion sensing, this report proposes a hybrid of these two optical nano-elements, namely, a CM/PCS hybrid. This structure was successfully fabricated by a simple and rapid process using nanoimprinting and spin-coating, which enabled control of the CM thickness.

View Article and Find Full Text PDF

Herein, we describe the development of a novel material, "enzyme-responsive fluorescent ionic liquid", which enabled a highly sensitive detection of alkaline phosphatase (ALP). We prepared a plasticized poly(vinyl chloride) (PVC) membrane using this new material as a plasticizer and quantified ALP in aqueous solutions. Preliminary results suggested that the PVC membrane responded to ALP at an interface between the membrane and the sample solution with anion extraction to maintain electroneutrality in the membrane phase.

View Article and Find Full Text PDF