Highly selective chemiluminescence detection of hydroxyl radical via increased π-electron densities of rhodamine B on montmorillonite matrix

The current chemiluminescence (CL) probes for hydroxyl radical (center dot OH) are poorly selective owing to a non-specific redox reaction. To the best of our knowledge, there have not been established on the CL probes for center dot OH using the strong electrophilicity of center dot OH. In this work, an ultrastrong CL emission is initiated by electrophilic attack of center dot OH towards rhodamine B (RhB) on the surface of montomorillonite (MMT). The improved CL emissions are attributed to the oriented H-type aggregation of RhB molecules on the surface of MMT by pi-pi stacking interactions, resulting in an increase in pi-electron density of aromatic ring of RhB. The high pi-electron density of benzene ring could facilitate the attack of electrophilic center dot OH towards RhB. In addition, a novel CL probe for center dot OH with high selectivity and high sensitivity has been established using the electrophilic properties of center dot OH rather than its common redox properties. The applicability of the proposed CL probe is evaluated by detecting center dot OH in untreated and gentamicin treated mouse fresh plasma samples. Our findings provide a new strategy to improve the selectivity of CL sensor of center dot OH. (C) 2015 Elsevier B.V. All rights reserved.