Studying collagen self-assembly by time-lapse high-resolution atomic force microscopy.

Fibrillar collagens constitute a main component of many tissues, where they form a scaffold for cell attachment and provide mechanical strength. Gaining insight into molecular mechanisms of collagen self-assembly from in vitro experiments is important for better understanding the complex hierarchical processes involved in collagen fibril formation in vivo. In addition, such insight can be used to assemble collagen into desirable structures for the biofunctionalization of surfaces in different biotechnological and medical applications. Here, we describe a method to direct the assembly of type I collagen into well-defined nanoscopic matrices of different patterns. Within these matrices, the self-assembly of collagen molecules into fibrils can be directly observed by time-lapse atomic force microscopy (AFM). High-resolution AFM topographs reveal substructural details of the collagen fibril architecture and provide information about mechanisms and dynamics of fibril formation.