As the most abundant (25 to 35%) protein in mammals, collagen is found everywhere in connective tissues, including bone, skin, and muscle. Thus characterization of the structure, compositions, and mechanical properties of collagen fibrils is crucial in understanding their performance over time.

Atomic force microscopy (AFM), as a powerful nanotechnology tool, has been widely used to determine the morphology, mechanical properties, and in situ self-assembly processes of collagen fibrils. Conventional techniques to characterize these collagen fibrils are mainly based on AFM force-volume spectroscopy, which collects force-distance (F-d) curves at each pixel to calculate material properties. However, these techniques have been recognized as being exceedingly slow. It takes hours to acquire an elasticity map. Driven by the demand for a much faster technique, Park Systems developed the PinPoint Nanomechanical Mode to provide a solution that is at least 100 times faster than traditional techniques. With this application, an elasticity map can be acquired within minutes and with a correlated topography image that reveals the position and orientation of the sample. This mode represents a new application tool for acquiring real-time topography and quantitative mechanical property maps of various materials, ranging from hard disks to soft tissues. Here, we report imaging collagen fibrils using the PinPoint Nanomechanical Mode.