Regenerable bipolar electrochemiluminescence device using glassy carbon bipolar electrode, stainless steel driving electrode and cold patch

Abstract

A regenerable bipolar electrochemiluminescence (ECL) device was designed using glassy carbon rod as bipolar electrode (BPE), stainless steel rod as driving electrode, and cold patch for the construction of ECL cell. Two glassy carbon rods linked with a copper wire and two stainless steel rods were embedded perpendicularly into polypropylene slide to make electrode chip. The cheap and commercially available cold patch with a hole can be repeatedly removed and attached to flat electrode chip to form a ECL cell free from solution leakage. The combination of polishable electrode and repeatedly attachable cold patch enables the facile regeneration of bipolar ECL device. Interestingly, the use of stainless steel as driving electrode remarkably reduce background ECL from driving electrode at appropriate voltage probably because of the formation of thick passivation layer. This newly developed bipolar ECL device is simple, cost-effective and its BPE has high conductivity. Based on the advantages above, it is used to detect hydrogen peroxide by luminol ECL using a smart phone as a portable detector. The obtained calibration curve of the proposed method demonstrates a good linearity in the range from 5.0 μmol L−1 to 300 μmol L−1 with a limit of detection of 3.67 μmol L−1 (S/N = 3:1). This device has been successfully employed for the detection of medical hydrogen peroxide solution and displayed excellent recovery.