A stopped‐flow study of the dual chemiluminescence for the luminol–KIO₄–Mn²⁺ system in strong alkaline solutions

Abstract

A novel phenomenon of dual chemiluminescence (CL) was observed for the KIO4-luminol-Mn(2+) system in strong alkaline solutions using the stopped-flow technique. Scavenging study of the reactive oxygen species (ROS) suggested that the two CL peaks originated from different CL pathways precipated by distinct ROS (O2(-) and •OH for the first peak, mainly 1O2 for the second peak). Generation of these ROS at different time intervals from the reactions involving IO4(-), O2, and Mn(2+) and their subsequent reactions with luminol induced the intense CL emission. The relative intensity of the two CL peaks can be tuned over a wide range by varying the concentrations of Mn(2-), luminol and KIO4. Because of the involvement of different ROS in each pathway, the two CL peaks could respond quite differently to various substances. Moreover, variation of the intensity ratio of the two CL peaks altered the relative proportions of the corresponding ROS, thereby changing their responses to a given substance. The dual CL emission acts like a pair of tunable probes and it is believed that this CL system has great potential in analytical applications.

Enhanced chemiluminescence of cerium(IV)–Tween 85 system and the analytical application

“…The oxidation of some polyphenols formed singlet oxygen 1 O 2 * to give weak CL (37)(38)(39). Light emission spectra generate two peaks with a maximum wavelength of 475-505 nm and 635 nm.…”

“…The structural formula of Tween 85 contains several alkane hydroxyl groups (CH 2 -OH), which could be oxidized to form singlet oxygen 1 O 2 * (27,28). The oxidation of some polyphenols formed singlet oxygen 1 O 2 * to give weak CL (37)(38)(39). Light emission spectra generate two peaks with a maximum wavelength of 475-505 nm and 635 nm.…”

A kinetic treatment of stopped‐flow time courses for multiple chemiluminescence of the KIO4‐luminol‐Mn2+ system

“…All CL measurements were performed on a Hitech SF‐61 stopped‐flow spectrofluorimeter (Hitech Scientific, Wilts, UK) as described previously . CL experiments were performed in the fluorescence mode with the light source switched off.…”

“…However, most studies have relied on flow injection analysis for CL measurements, precluding the detection of any multiple CLs. Recently, we reported the dual CL emission of the luminol‐KIO 4 ‐Mn 2+ system using a stopped‐flow technique . The dual CL emission was postulated to originate from different CL pathways due to distinct ROSs (O 2 − , • OH and 1 O 2 ) generated in the reactions involving IO 4 − , O 2 and Mn 2+ .…”

Evaluation of the Potentiality of the H2O2/IO4– Process for the Removal of Acid Orange 10 from the Liquid Phase: Experimental Investigation Coupled with Numerical Analysis Using the Box–Behnken Design

“…In addition, periodate can break cellulose chains by cleaving the C2–C3 bond of the glucopyranoside ring . H 2 O 2 /IO 4 – represents a chemiluminescence (CL) system adopted in various fields of analytical chemistry for the determination of organic substances in different matrices and recently investigated for the degradation of refractory organic compounds. , The complex reaction mechanisms and numerous potential species formed for the hydrogen peroxide/periodate system, also as a function of the aqueous medium pH, have been deeply discussed in different literature works. − As an example, Shah et al , examined the CL produced by the H 2 O 2 /IO 4 – system in the presence and absence of nitrogen-doped carbon dots (N-CDs) and NaOH.…”