Quenching Effects of Graphene Oxides on the Fluorescence Emission and Reactive Oxygen Species Generation of Chloroaluminum Phthalocyanine

Abstract

The photophysical behavior and reactive oxygen species (ROS) generation by chloroaluminum phthalocyanine (AlClPc) are evaluated by steady state absorption/emission, transient emission, and electron paramagnetic resonance spectroscopies in the presence of graphene oxide (GO), reduced graphene oxide (RGO), and carboxylated nanographene oxide (NGO). AlClPc and graphene oxides form a supramolecular structure stabilized by π-π interactions, which quantitatively quenches fluorescence emission and suppresses ROS generation. These effects occur even when graphenes are previously functionalized with Pluronic F-127. A small part of quenching is due to an inner filter effect, in which graphene oxides compete with AlClPc for light absorption. Nonetheless, most of the (static) quenching arises on the formation of a nonemissive ground state complex between AlClPc and graphene oxides. The efficiency of graphene oxides on the fluorescence quenching and ROS generation suppression follows the order: GO < NGO < RGO.

The Role Played by Graphene Oxide in the Photodeposition and Surface‐Enhanced Raman Scattering Activity of Plasmonic Ag Nanoparticle Substrates

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A Photo‐Stable Indocyanine Green and Rapamycin Co‐Delivery System Based on Poly(Glutamic Acid)‐Modified Manganese Phosphate for Synergetic Tumor Therapy

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Electronic spectroscopy of graphene obtained by ultrasonic dispersion

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