Fig. 7.

Paper-based microfluidic ECL sensor system. (a) Paper microfluidics produced in bulk using an inkjet printer. (b) The hydrophilic portion of the paper is filled with a 10 mM Ru(bpy)₃²⁺ solution and then dried. (c) The paper substrate is then laminated onto the screen-printed electrode using transparent plastic. A drop of sample is introduced through a small aperture in the plastic at the base of the channel. Then, after the detection zone is fully wetted, a potential of 1.25 V is applied, and the sensor is placed close to the lens of a camera phone (d) to capture the resulting emission. (e) ECL images from the paper-based sensor for various concentration of DBAE. (f) Calibration curve showing ECL response between 0.5 mM and 20 mM DBAE, using paper microfluidic ECL sensor. Adapted with permission from reference.⁹³