Accueil > Séminaires > Précédents séminaires > Fluorescent protein senses and reports mechanical damage in fibre-reinforced polymer composites

Fluorescent protein senses and reports mechanical damage in fibre-reinforced polymer composites

Prof. Nico Bruns Adolphe Merkle Institute, University of Fribourg, Switzerland

Some molecules change their colour or fluorescence in response to mechanical forces. When incorporated in polymeric materials, these mechanophores become useful probes that enable detection of micron scale-damage or render stress distributions visual. The fluorescence of fluorescent proteins is linked to their native structure, which can be distorted by mechanical forces. Enhanced yellow fluorescent protein (eYFP) loses its yellow fluorescence when subjected to macroscopic forces. This protein was implemented as a mechanophore in a polymeric material. eYFP was used as a force-sensitive link at the interface between epoxy resin and glass- or carbon-fibres in reinforced composites. The biomolecule reports shear debonding and barely visible impact damage by loss of fluorescence (Figure 1). The resulting self-reporting materials could find application as a safety feature in load-bearing components to prevent catastrophic material failure.

Figure 1. Fluorescent protein acting as a force-responsive molecular sensor at the fibre-resin interface in glass-fibre reinforced composites. Micrometer-scale damage, such as fibre fractures and fibre-matrix debonding, is reported by loss of yellow fluorescence in the damaged areas due to a force-induced unfolding of the protein.

References :

N. Bruns, K. Pustelny, L. M. Bergeron, T. A. Whitehead, D. S. Clark, Angew. Chem. 2009, 121, 5776-5779 ; Angew. Chem. Int. Ed. 2009, 48, 5666-5669.

K. Makyła , C. Müller, S. Lörcher, T. Winkler, M. G. Nussbaumer, M. Eder,
N. Bruns, Adv. Mater. 2013, 25, 2701-2706.