| AVS 55th International Symposium & Exhibition | |
| BioMEMS Topical Conference | Tuesday Sessions |
| Session BM-TuP |
| Session: | BioMEMS |
| Presenter: | T. Chen, Duke University |
| Authors: | T. Chen, Duke University R. Desikan, Oak Ridge National Laboratory R.H. Datar, Oak Ridge National Laboratory R.P. D, Oak Ridge National Laboratory T.G. Thundat, Oak Ridge National Laboratory S. Zauscher, Duke University |
| Correspondent: | Click to Email |
There is considerable interest in microcantilevers grafted with stimulus-responsive polymer brushes for sensor applications in aqueous environments, as they potentially provide a much larger cantilever bending response to changes in stimuli, such as temperature, light, chemical, and pH compared with cantilevers decorated with self-assembled monolayers (SAMs). To engineer sensitivity to specific stimuli, functional monomers can be incorporated into polymer brushes via copolymerization and functional moieties can be introduced through subsequent chemical modification. As boronic acid can bind diols through reversible boronate ester formation, incorporation of boronic acid into linear copolymers such as latex and polymer gels for the detection of glucose has been shown. Herein, we show the synthesis of novel glucose-responsive poly(N-isopropylacrylamide)-co-poly(acrylic acid)-(3-aminophenylboronic acid) (pNIPAAM-co-pAA-PBA) polymer brushes, and explore their use in a prototypical example for their potential as polymer brushes-functionalized microcantilevers firstly for the detection of blood glucose at physiologically relevant concentrations. We evaluated the stimulus-response of the polymer brushes to changes in glucose concentration and solution pH by measuring concomitant brush height changes. Glucose-responsive pNIPAAM-co-pAA-PBA brushes show a large, reversible swelling response in presence of free glucose at physiologically relevant concentrations. The deflection and surface-stress response of microcantilevers, functionalized with PBA-brushes, is substantially larger and faster than that for PBA-SAM functionalized levers. This shows the promise of pNIPAAM-co-pAA-PBA brushes for microcantilever glucose sensing applications, and demonstrates, more generally, the potential of responsive polymer brushes to sense and transduce changes in a solution environment efficiently.