Project Details
Projekt
Raman-AFM
Subject Area
Polymer Research
Term
Funded in 2023
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 532413737
The proposed Raman-AFM instrument is a versatile tool that combines two powerful techniques for analyzing materials: Raman spectroscopy and atomic force microscopy (AFM). Raman spectroscopy uses a laser to excite molecules in a sample and measures the scattered light to detect and identify the chemical composition of a sample. AFM measures the physical properties of a material at the nanometer level by using a tiny probe that is scanned across a surface. By combining these two techniques, a Raman-AFM instrument can provide a detailed chemical, topological and mechanical characterization of the sample on the nanoscale. The acquisition of nanometer-level chemical information on a material surface is a unique capability of the instrument and still at the technological forefront in microscopy at large. This is made possible by driving the Raman-AFM in so-called tip enhanced Raman spectroscopy (TERS) mode. TERS selectively enhances Raman scattering in the nanoscopic region where the AFM tip is positioned, overcoming the diffraction-induced resolution limit of Raman microscopy, and enables, for example, nanometer-scale chemical imaging of nanoparticles, polymer blends, or various biomolecules even including the sequencing of RNA. Raman-AFM and in particular the TERS mode have also been successfully employed to characterize complex biological systems such as cells and viruses, as well as nucleic acids, proteins, peptides, and lipid membranes. In this proposal, these capabilities will be used for studying the molecular interaction and structure formation of a variety of biomacromolecules, focusing on self-assembling and phase-separating macromolecules, glycosaminoglycans (GAGs), mucins and polymeric mimetics thereof. Their biological function is tightly connected to self-assembly and clustering processes, but the underlying mechanisms are poorly understood. Raman-AFM will shed light on the nanoscopic organization principles for self-assembly and clustering, e.g., charge patterns, hydrophobic / hydrophilic domains as well as the molecular composition of the self-assembled structures. The intended setup will be particularly suitable for analyzing samples in controlled environments (including fluids) to analyze changes in physical and chemical properties of dynamic materials as well as bio-functional materials over time and varying stimuli. Thus, the instrument will provide cutting-edge material analysis for the materials developed by the investigators as outlined in this proposal. Furthermore, these studies will enable new insights concerned with fundamental questions by correlating the structure of bio- and biomimetic macromolecular assemblies with their biological function.
DFG Programme
Major Research Instrumentation
Major Instrumentation
Raman-AFM
Instrumentation Group
5091 Rasterkraft-Mikroskope
Applicant Institution
Albert-Ludwigs-Universität Freiburg
