Optofluidic Integrated Sensor on Glass for Harsh Environment Measurements: Case of Plutonium(VI) in Nitric Acid
Résumé
In this paper, we present an optofluidic device made by combining a chemical etching procedure with ion-exchange to build microchannels in a glass substrate along with optical waveguides. The device is used to measure the concentration of plutonium (VI) in a solution of nitric acid by the infrared absorption spectroscopy technique. Light confined in waveguides interacts with the fluid by means of the evanescent part of the fundamental mode, over a length of 2 cm. Care is devoted to the device assembly (in particular by means of low-temperature molecular bonding) and pigtailing with optical fibers, so that the device can be put in a commercial microfluidic chip holster. The packaged device has proven to be sturdy enough so that it can be used inside of a nuclearized glove box. First measurements have been done by means of plutonium (VI) in a nitric acid solution.