Gold functionalised attapulgite for discrimination of hydrogen peroxide and oxidising ions

Aiming to monitor hydrogen peroxide and oxidizing ions in aqueous circumstance, functionalized attapulgite [i.e. gold-modified attapulgite nanocomposites (Au/ATP NCs)] as peroxidase mimics were prepared by loading β-cysteamine-capped gold nanoparticles onto attapulgite with the use of electrostatic interactions. As-prepared Au/ATP NCs were used for the detection of H₂O₂. The linear range and detection limit for H₂O₂ were determined by quantitative experiments emerging excellent stability and recyclability. The peroxidase-like activity of Au/ATP NCs could be expanded for the detection of some oxidative ions (Fe³⁺ and Ag⁺) was also been discovered. Based on the absorption spectrum and steady-state kinetics, the mechanism for peroxidase mimic reaction is investigated. This work represents the first example of multitarget detection for molecule and cations (H₂O₂, Fe³⁺ and Ag⁺) using Au/ATP NCs as peroxidase enzyme mimics and holds a promise for future biomedical and analytical applications.