Mechanically Modulating the Photophysical Properties of Fluorescent Protein Biocomposites for Ratio- and Intensiometric Sensors

Mechanically sensitive biocomposites comprised of fluorescent proteins report stress through distinct pathways. Whereas a composite containing an enhanced yellow fluorescent protein (eYFP) exhibited hypsochromic shifts in its fluorescence emission maxima following compression, a composite containing a modified green fluorescent protein (GFPuv) exhibited fluorescence quenching under the action of mechanical force. These ratio‐ and intensiometric sensors demonstrate that insights garnered from disparate fields (that is, polymer mechanochemistry and biophysics) can be harnessed to guide the rational design of new classes of biomechanophore‐containing materials. Under pressure: Poly(methyl methacrylate) composites containing either enhanced yellow fluorescent protein (eYFP) or genetically modified green fluorescent protein (GFP; see scheme) exhibited changes in photophysical properties under pressure. Whereas the eYFP composites functioned as ratiometric sensors through shifts in their fluorescence emission wavelengths, the GFP composites were intensiometric and underwent fluorescence quenching under mechanical force.