Single molecule forces for poly-L-lysine homopolymer

Graphic of force spectroscopy concepts. A single polymer molecule is covalently attached to the AFM tip by a linker (here, polyethylene glycol, PEG). (bottom) Force-distance curve for poly-L-lysine on a hydrophobic self-assembled monolayer (SAM) in water. The force plateau indicates the desorption of a single polymer from the surface. Histograms obtained from multiple force curves provide the average desorption force (inset, top) and detachment length (inset, bottom). Ref. S. Kienle, T. Pirzer, S. Krysiak, M Geisler, and T. Hugel,Faraday Discuss. 160, 329 (2013).