Apparent dependence of rupture force on loading rate in single-molecule force spectroscopy.

摘要: Force spectroscopy is becoming an important tool in physicochemical research and allows the extraction of kinetic parameters dissociation that are not available to other techniques. The theory single-molecule force has received considerable attention over last several years continues be developed. Atomic microscopy (AFM) measurement mode one most common methods perform measurements. In these experiments, rupture forces between interacting molecules measured as a function AFM probe velocity. resulting dependence probable on loading rate then used extract information. Although this technique widespread, we find some experimental aspects require more thorough consideration. One seemingly simple methodology extracting from curve. Herein, discuss how might have significant impact interpretation Consider force-separation curve with event shown Figure 1. A part corresponding stretching polymeric tether prior without added noise solid line. With show amount scatter. Therefore, if obtained difference outstanding data points vicinity event, root-mean-square (RMS) amplitude will force, illustrated figure. RMS depend pulling velocity therefore affect Fn v can written [Eq. (1)]: