AFM-based identification of the dynamic properties of globular proteins

The analysis using a mathematical model rather than relying on experiment is essential in understanding the motion and mechanics of biological molecules with less cost. This paper investigates a real-time identification method for estimating the mechanical properties of the proteins in motion using an AFM-based nanomanipulation system. First, an AFM-based bio-characterization system is introduced. Second, a dynamic model for the interaction between an AFM cantilever in fluid and globular proteins is presented. Finally, based on a second-order time-varying linear model representing the protein-AFM interaction, a real-time estimation method of the mechanical properties of globular proteins is proposed. Simulation results and discussions are included. This technique can be used to determine the model of protein motion for the purpose of computer simulation and for a real-time modification of protein deformation.