Sensitive Nonenzymatic Electrochemiluminescence Determination of Hydrogen Peroxide in Dental Products Using a Polypyrrole/Polyluminol/Titanium Dioxide Nanocomposite Publisher



Hamtak M¹ ; Fotouhi L¹ ; Hosseini M² ; Reza Ganjali M^{3, 4} Show Affiliations
Source: Analytical Letters Published:2019

Abstract

A layer-by-layer assembled of a polypyrrole and polyluminol was synthesized through the electrodeposition of pyrrole and luminol in acidic medium on a graphite electrode. The electrode was then modified by casting titanium dioxide (TiO 2 ) nanoparticles on its surface for enhancing electrochemiluminescence of luminol. The properties of this electrochemiluminescence sensor were studied by cyclic voltammetry, electrochemical impedance spectroscopy, field emission scanning electron microscopy, and energy dispersive X-ray spectroscopy. The results demonstrated that the modification of this electrochemiluminescence sensor shows sensitive response for the determination of hydrogen peroxide. Figures of merit include broad linearity from 1 pmol L −1 to 4 µmol L −1 (R 2 = 0.996) with a limit of detection as low as 0.40 pmol L −1 at a signal-to-noise ratio of three and good reproducibility with relative standard deviation of 4% for the determination of a 400 nmol L −1 hydrogen peroxide solution (n = 4), along with favorable long-term stability. The presence of glucose, citric acid, uric acid, dopamine, and ascorbic acid at concentrations as high as 100 nmol L −1 of H 2 O 2 did not produce any electrochemiluminescence signals, which demonstrates the selective nature of this modified electrode. The sensor was also used for the determination of H 2 O 2 in mouthwash formulations and dental whitelight gels. © 2018, © 2018 Taylor & Francis.