We have developed sensor arrays containing non-covalent gold nanoparticle-fluorescent polymer assemblies to identify and quantify biological targets in minutes using a platreader platform. These sensors can identify protein targets at nanomolar concentrations in both buffer and human serum, and to differentiate between species and even different strains of bacteria. In more recent studies we have demonstrated that these sensor systems can discriminate between isogenic healthy, cancerous and metastatic cells.