Enzyme‐Responsive Nanoparticle Systems

Abstract Inorganic nanoparticles and their accompanying diverse physical properties are now virtually in routine use as imaging tools in cell‐biology. In addition to serving as excellent contrast agents, their size‐ and environment‐dependent optical and magnetic properties can be harnessed to create enzyme biosensor devices of extremely high sensitivity, whilst circumventing the numerous technical limitations associated with traditional enzyme assays. In this Research News article we discuss recent advances in field of enzyme‐responsive nanoparticle systems, where the activity of an enzyme elicits a specific response in the nanoparticle assembly to produce a signal relating to enzyme activity, focusing on three important systems: DNA‐structured nanoparticles, protein kinases and proteases.