title: Method for time-resolved monitoring of a solid state biological film using photothermal infrared nanoscopy on the example of poly-L-lysine.
abstract: We report time-resolved photothermal infrared nanoscopy measurements across a spectral range of more than 100 cm(-1) (1565 cm(-1) to 1729 cm(-1)) at nanoscale spatial resolution. This is achieved through a custom-built system using broadly tunable external cavity quantum cascade lasers in combination with a commercially available atomic force microscope. The new system is applied to the analysis of conformational changes of a polypeptide (poly-l-lysine) film upon temperature-induced changes of the humidity in the film. Changes of the secondary structure from β-sheet to α-helix could be monitored at a time resolution of 15 s per spectrum. The time-resolved spectra are well comparable to reference measurements acquired with conventional Fourier transform infrared microscopy.
authors: Vienna University of Technology, Institute for Chemical Technologies and Analytics, Getreidemarkt 9/164 UPA, 1060 Vienna, Austria.
authors: Georg
authors: G
authors: Ramer
authors: Vienna University of Technology, Institute for Chemical Technologies and Analytics, Getreidemarkt 9/164 UPA, 1060 Vienna, Austria.
authors: Anna
authors: A
authors: Balbekova
authors: Vienna University of Technology, Institute for Chemical Technologies and Analytics, Getreidemarkt 9/164 UPA, 1060 Vienna, Austria.
authors: Andreas
authors: A
authors: Schwaighofer
authors: Vienna University of Technology, Institute for Chemical Technologies and Analytics, Getreidemarkt 9/164 UPA, 1060 Vienna, Austria.
authors: Bernhard
authors: B
authors: Lendl
mesh_terms: D006813:Humidity; D036103:Nanotechnology; D055668:Photochemical Processes; D011107:Polylysine / Q000032:analysis*; D013055:Spectrophotometry, Infrared; D013696:Temperature; D013997:Time Factors
chemical_list: D011107:Polylysine