Mid-Infrared nanospectroscopy to probe protein conformation at the nanoscale

Photothermal atomic force microscopy-assisted infrared nanospectroscopy is applied to investigate protein conformation at the nanoscale. In the framework of protein aggregation, the possibility to probe protein conformation on nanometr-sized structures, enabled us to identify structural differences among fibrils formed under different conditions. By adopting a difference IR nanospectroscopy approach (visible light ON-visible light OFF), we then probed, for the first time, subtle transient conformational changes of light-sensitive protein receptors embedded in individual native cell membrane patches.