Biomimicry Recognition of Proteins and Cells Using a Small Array of Block Copolymers Appended with Amino Acids and Fluorophores

Mimicking sensory principles encountered in animals, whereby numerous tastants and odorants are identified based on pattern-like sensory inputs that are generated by arrays of sensory cells, allows creating a unique technique that is distinct from conventional chemical sensing systems, as the latter usually require specific recognition of target analytes. Herein, we present a highly discriminative small fluorescent array of block copolymers that can recognize various bioanalytes in a biomimicry manner. These polyethylene glycol/poly-L-lysine block copolymers are functionalized with fluorescein as a fluorescent reporter unit and hydrophobic amino acids as cross-reactive recognition units, which provides the ability to generate fluorescent response patterns unique to proteins and cells. Multivariate analysis on the patterns obtained with an array consisting of solely 3 block copolymers allowed identifying not only 20 proteins and 10 mammalian cells individually but also complex protein mixtures with slightly different compositions. This design guideline for creating a versatile biomimicry sensing system, which is based on the bifunctionalization of polymeric materials, is expected to offer a powerful platform for simple and high-throughput sensing of a wide variety of bioanalytes.