Mechanically induced generation of counterions inside surface-grafted charged macromolecular films: Towards enhanced mechanotransduction in artificial systems

Brushing up on films: A simple model, based on strong ion-pairing interactions of a dye probe (bromothymol blue, BTB) within surface-grafted charged polyelectrolyte brushes, provides evidence that physical forces can be easily mechanotransducted into chemical signals (see picture, PDMS=poly(dimethylsiloxane)). The application of a mechanical force results in a shift of the equilibrium for BTB, which can be monitored by UV/Vis spectroscopy.