(322c) Super-Resolution Surface Mapping Using the Trajectories of Molecular Probes

We have developed a new chemical imaging method, MAPT (Mapping using Accumulated Probe Trajectories) that generates maps of surface interactions based on the quantitative behavior of dynamic probe molecules.  The approach is based on distributing different aspects of molecular trajectories (e.g. adsorption events, diffusive steps, and desorption events) into distinct locations and then combining many trajectories to generate spatial maps.  The maps are super-resolution in nature, because they are accumulated from single molecule observations, each of which is highly localized.  Unlike other super-resolution techniques, which report only photon or point counts, our analysis generates spatial maps of physical quantities (adsorption rate, desorption probability, local surface diffusion coefficient, surface coverage/occupancy) that are directly associated with the molecular interactions between the probe molecule and the surface.  This allows for the analysis of heterogeneous surfaces in terms of absolute physical quantities, instead of relative contrast mechanisms.  We demonstrate the feasibility of this characterization using a surface patterned with various degrees of hydrophobicity.