Regensburg 2025 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

CPP: Fachverband Chemische Physik und Polymerphysik

CPP 15: Poster Session I

CPP 15.51: Poster

Monday, March 17, 2025, 19:00–21:00, P4

Direct stochastic optical reconstruction microscopy (dSTORM) on cationic copolymer microgels — •Evelyn Gettinger and Thomas Hellweg — Physical & Biophysical Chemistry, University Bielefeld, Bielefeld, Germany

Microgels, three-dimensional polymer networks with colloidal dimensions, are promising candidates for catalysis, sensory and drug delivery applications due to their responsive properties. Cationic copolymer microgels, in particular, are gaining increasing attention in research, as they are suitable for conjugation with biomolecules like peptides, antibodies, and nucleic acids. Poly(NNPAM-co-DAPMA) is one such microgel that exhibits thermoresponsiveness through the monomer N-n-propylacrylamide (NNPAM) and pH responsiveness through the cationic comonomer N-3-(dimethylamino)propylmethacrylamide (DAPMA). This study investigates the network structure of Poly(NNPAM-co-DAPMA) microgels using direct stochastic optical reconstruction microscopy (dSTORM), a high-resolution fluorescence technique. Microgels with varying DAPMA concentrations were synthesized and analyzed for swelling behavior and polydispersity using photon correlation spectroscopy (PCS). Morphological properties were examined with atomic force microscopy (AFM). Post-synthetic fluorescence labeling with the anionic dye DY-654-carboxylic acid revealed a gradient of fluorophore localization from the core to the periphery and concentrated fluorophore domains, indicating a heterogeneous network with random comonomer distribution.

Keywords: microgels; acrylamides; dSTORM; microscopy; fluorescence