1 Catalytically Active Copper Phosphate–Dextran Sulfate Microparticle Coatings for Bioanalyte Sensing Pietro Pacchin Tomanin, Sukhvir Kaur Bhangu, Frank Caruso* and Francesca Cavalieri* Dr. P Pacchin Tomanin, Dr. S K Bhangu, Prof. F Caruso ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, and the Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia. E-mail: fcaruso@unimelb.edu.au Dr. S K Bhangu , Dr F. Cavalieri School of Science, RMIT University, Melbourne, Victoria 3000, Australia. E-mail: francesca.cavalieri@rmit.edu.au Dr F. Cavalieri. Dipartimento di Scienze e Tecnologie Chimiche, Università di Roma ‘‘Tor Vergata’’, via della ricerca scientifica 1, 00133, Rome, Italy. Keywords: porous microparticles, nonenzymatic sensors, copper phosphate, dextran sulfate Engineering reactive and functional nanostructured surfaces is important for enhancing the sensitivity and versatility of biosensors and microreactors. For example, the assembly of hybrid inorganic–organic porous microparticles on surfaces may provide a catalytic microenvironment for a wide range of reactions. Herein, the synthesis of catalytically active porous dextran sulfate–copper phosphate hybrid microparticles by a facile and rapid crystallization process in aqueous solution is reported. The sulfated polysaccharide enabled control over the size and hierarchical morphology of the hybrid microparticles, as well as their assembly into stable macroporous coatings. The engineered microparticle coatings displayed intrinsic nonenzymatic peroxidase-like catalytic activity when employed as a platform for the detection of hydrogen peroxide. Pairing of the microparticle coating with glucose oxidase afforded a hybrid platform that was employed as a glucose sensor for monitoring physiological concentrations of a given analyte via a hybrid enzymatic/nonenzymatic cascade reaction. This work presents a strategy for the assembly of hybrid porous microparticles into enzyme-mimicking surfaces for copper- based catalysis and biochemical analyte sensing.