Luminol immobilized graphite electrode as sensitive electrochemiluminescent sensor for the detection of hydrogen peroxide

The present work, presents the Luminol immobilized electrochemiluminescence (ECL) for the detection of hydrogen peroxide. Herein, the ECL behavior of luminol immobilized on graphite as a paste electrode has been studied in nearly neutral solution (pH = 8) for the detection of hydrogen peroxide. Under the optimized conditions, a strong electron-transfer reaction occurs between luminol immobilized electrode and hydrogen peroxide in solution. Electrochemiluminescence response of proposed sensor for hydrogen peroxide was linear in the range of 1 × 10⁻⁸ to 1 × 10⁻³ μM with detection limit of 0.7 × 10⁻⁸ μM ​(S/N ​= ​3) at +0.6 ​V in PBS (pH ​= ​8). The sensor showed response for hydrogen peroxide concentration in less than 7 ​s. The prepared electrode is simple, fast, reproducible and stable. The effect of EDTA and other divalent interfering metal ions in the presence of hydrogen peroxide was also studied. The successful application of Luminol based ECL sensor was employed to study hydrogen peroxide in commercial hydrogen peroxide samples.