A hydrogel bi-layer structure is used to convert an absorption type to a more convenient fluorescent type probe film for aqueous nitric oxide (NO) and nitrite (NO2-). In the bottom layer the commercial probe molecule 1,2-diaminoanthraquinone (DAQ) is dispersed in poly 2-hydroxyethyl methacrylate (poly HEMA), in the top layer the red inorganic phosphor is dispersed in poly HEMA. Both optical excitation and detection is from the bottom. This bi-layer is integrated with organic light-emitting diode (OLED) and organic photo-detector to form a real-time solid-state sensor. The sensor is responsive to NO bubbling, and remains stable in acid condition.
- Nitric oxide
- Solid-state real-time sensor