Authors: M. Bayindir, A. Yildirim, M. Vural, M. Yaman
Affilation: Bilkent University, Turkey
Pages: 20 - 23
Keywords: optofluidics, photonic band gap fiber, artificial nose, optoelectronic sensor
We introduce and demonstrate the capabilities of a novel integrated optoelectronic-microfluidic sensor array that can rapidly distinguish millions of, trace level volatile chemicals based on their spectroscopic fingerprints inside flexible optofluidic channels. The system consists of an array of hollow core fibers that have integrated dielectric mirrors to guide infrared light. Dielectric mirrors are reflectors that can be fabricated to reflect any selected spectral according to their nanostructure. For the first time, we are showing that wavelength scalable hollow core fibers can be used as ‘wavelength selectors’ to selectively guide blackbody radiation without necessitating expensive bulk tunable laser systems. We then use this array of micro-channels to detect volatile organic analytes as they pass inside the channels. The transducing mechanism is waveguide enhanced infrared absorption using a simple blackbody radiation source and an inexpensive integrative infrared detector. In the presence of an infrared active complex molecule in a spectrally coinciding channel the transmission signal is quenched to a degree to deduce the absorbing bond. The collective response from the sensor matrix is used to distinguish and identify the analyte either from other analytes or from a database. The sensitivity of the optoelectronic ‘nose’ is low ppm (parts per million) to ppt (parts per trillion) levels. The selectivity can be increased arbitrarily to match that of commercial Fourier Transform Infrared Spectrometers.