Microfluidic optoelectronic sensor array for detection of dissolved CO2 based on halocromic dye-doped polymeric microbeads

摘要

We present a microfluidic optoelectronic sensor for detection of dissolved CO2 in aqueous samples. The sensor contains an array of wells embedded in a microfluidic device and filled with ion-exchange polymeric microbeads doped with halocromic dyes. We have developed a simple procedure for microbeads deposition that allows incorporation of virtually any combination of halocromic dyes, providing a route for cross-reactive sensing. Due to a versatile optical arrangement, using LEDs and photodiodes, optical signals are easily translated into electronic readouts. We demonstrate the sensor ability to provide distinct responses to different concentrations of dissolved CO2. Moreover, the sensor shows no cross sensitivity to acidity not related to dissolved CO2.