Visualizing molecular structure and function in soft matter using vibrational microscopy

Structure-function relationships define the how molecular processes give rise to macroscopic observables. In this talk, I will present an overview of our recent work using nonlinear vibrational spectroscopic imaging to reveal unique structural-function relationships in polymeric soft matter systems. I will give a short introduction of the spectroscopic tool that we have developed, which allows us to spatially map chemical bonding with optical resolution on the millisecond timescale. We have used this technology to map protein structure in fibrin biopolymer networks (that lie at the heart of blood coagulation) and demonstrated that fibrin biopolymers change structure in a spatially heterogeneous manner when exposed to tensile loads. This result hints at a unique self-regulating mechanism via a direct biophysical feedback loop in a physiological context. In another example, we have shown that microscopic water and macroscopic proton transport are related in nano-structured polymer fuel cell membranes, allowing us to propose a clear target for constructing highly efficient fuel cell materials.