Open bipolar electrode-electrochemiluminescence imaging sensing using paper-based microfluidics

Abstract

A novel paper-based open bipolar electrode-electrochemiluminescence (P-o-BPE-ECL) sensing has been developed for visual detection. Wax-screen-printing was employed to make microfluidic channels on filter paper, and the carbon ink-based BPE and driving electrodes were screen-printed on paper. An inexpensive CCD camera was used as a detector for imaging sensing. In this study, two P-o-BPE-ECL imaging sensing platforms were demonstrated. For the first one, a hydrophilic paper channel was used to host a single “band”-shaped BPE. Under optimal conditions, this P-o-BPE-ECL platform successfully fulfilled the imaging sensing of tri-n-propylamine (TPA) with a linear range from 10 to 1000μM with a detection limit of 8.7μM. In addition, the determination of H2O2 using this platform could be performed in the linear range of 50μM to 5000μM with a detection limit of 46.6μM. For the second platform, an open BPE array configuration has been proposed for P-o-BPE-ECL sensing, where eleven BPEs were stridden across the two legs of the “U”-shaped paper channel. On this prototype, a simple screening application has been performed. These results show that the proposed strategy offers great promise in providing a simple, low-cost, rapid and environment-friendly solution for biochemical applications.