Synergistic enhancement effects of cobalt oxide doped silver oxide and porphyrin zinc on an electrochemiluminescence sensor for detection of glucose

Abstract

An electrochemiluminescence sensor was prepared by modification of glassy carbon electrode with multiwall carbon nanotubes, tris (2, 2′-bi-pyridyl) ruthenium (II), cobalt oxide doped silver oxide and porphyrin zinc in sequence. In this platform, multiwall carbon nanotubes worked as the carrier, carrying tris (2, 2′-bi-pyridyl) ruthenium (II), and cobalt oxide doped silver oxide and porphyrin zinc were used as co-reaction accelerators of tris (2, 2′-bipyridine) ruthenium (II) /tri-n-propylamine system. The synergy of cobalt oxide doped silver oxide and porphyrin zinc promoted the electron transfer, thus enhancing the ECL performance. The possible reaction mechanism of the sensor was researched. Moreover, the experimental results showed that glucose also had a certain sensitizing effect on the system. The parameters that affected the performance of the sensor were optimized. The electrochemiluminescence intensity was linear with the logarithm of glucose concentration under the optimal conditions. And the linear range was 1.0 × 10−9 to 5.0 × 10−4 mol·L−1, the detection limit was calculated to be 3.3 × 10−10 mol·L−1 (S/N = 3). The developed ECL sensor demonstrated good sensitivity, selectivity, stability and reproducibility for the determination of glucose in biological systems.