Organic molecule enhanced 1O2 electrochemiluminescence from the phase transformation of amorphous calcium phosphate. (20th November 2020)

• Record Type: Journal Article
• Authors: Sun, Shuquan; Chen, Qixuan; Ran, Guoxia; Song, Qijun
• Is Part Of: Electrochimica acta. Volume 361(2020)
• Publication Date: 2020-11-20
• Subjects: Electrochemiluminescence -- Singlet oxygen -- Amorphous calcium phosphate -- Phase transition -- Organic molecules; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2020.137062
• Languages: English
• ISSNs: 0013-4686

Abstract

Highlights: Amorphous calcium phosphate was in-situ assembled on Nafion coated glassy carbon electrode. Singlet oxygen electrochemiluminescence ( 1 O2 ECL) was generated during the transition of the assembled ACP The enhancement effect of organic molecules to the 1 O2 ECL is ascribed to the electrochemically generated alkoxy radicals. An ECL assay platform was presented for the sensitive detection of isopropanol (IPA), L-Lysine based on the phase transition of ACP. Abstract: Organic molecule enhanced the singlet oxygen ( 1 O2 ) electrochemiluminescence (ECL) generated during the phase transition of calcium phosphates (CaPs) is presented. As a classic precursor of hydroxyapatite (HAP, Ca10 (PO4 )6 (OH)2 ), amorphous calcium phosphate (ACP) was in-situ assembled on Nafion film (denoted as ACP/Nafion). The electrochemical oxidation peak and ECL phenomenon were observed when the ACP/Nafion electrode was subjected to cyclic voltammetry (CV) scanning in phosphate buffer solution. The characteristic spectrum of 1 O2 dimol emission was observed at 634 nm. And the ECL intensity could be markedly increased and stabilized in the presence of organic molecules, e.g., isopropanol (IPA), oxalate (C2 O4 2− ) and L-Lysine. The electron spin resonance (ESR) measurement confirmed that a large number of relevant radicals were produced during the electrochemical oxidation, and these radicals are believed to have played the essential role for the 1 O2 generation. Based on the enhancement effect, we exploited the feasibility of direct ECL detection of IPA and L-Lysine by using the ACP/Nafion electrode. And the results show that IPA and L-Lysine can be detected in the range 1.0 μ M to 1.0 mM and 0.1 μ M to 0.1 mM, with a limit of detection (LOD) 0.15 and 0.03 μ M respectively for IPA and L-Lysine. Thus present work not only provides insight for the organic molecule enhanced 1 O2 ECL, but also shows the potential for the development of widely applicable ECL detection platform based on abundantly available materials. Graphical abstract: Organic molecules greatly enhance the singlet oxygen electrochemiluminescence during the transition of amorphous calcium phosphate assembled on Nafion coated glassy carbon electrode. Image, graphical abstract