A novel microwave-assisted hydrothermal route has been demonstrated to allow the synthesis of hollow MnO2 particles with dandelion-like structure. The as-prepared particles show the ability to enclose PtAu bimetallic nanoparticles which good electrocatalytic activity toward the oxidation of glycerol and the reduction of oxygen in alkaline media, in addition to high stability, what we attribute to the MnO2 cage, which is responsible for the confinement of reaction intermediates impeding their diffusion to the bulk electrolyte. Considering the inherent properties of MnO2, such as low acute toxicity to living organisms, biocompatibility, stability in neutral and alkaline media and the ability to enclose other possible different materials, including functionalized nanoparticles, we suggest a broad field of potential application for these structures, such as drug delivery and bioimaging, catalysis, (bio)sensing, etc. (C) 2017 Elsevier B.V. All rights reserved.