Study of amyloid fibrils via atomic force microscopy

Protein fibrils are a crucial subject of study in various research fields and disciplines. Amyloid fibrils are highly ordered fibrillar structures assembled from either peptides or unfolded proteins, which have a great importance in biology, medicine and recently have started to find an important role in many nanotechnology applications. Understanding the mechanisms of fibrillation, the structural features, and the physical and mechanical properties of these fibrils is an essential step to both unraveling their biological role and also their successful applications in nanotechnology and material science. Atomic force microscopy (AFM) is one of the most widely used single-molecule techniques to study the properties of amyloid fibrils. In this review we will discuss how the application of AFM during last few years has allowed moving considerably forward in the research of amyloid fibrils. We will review how AFM has rapidly evolved from a purely microscopic technique, providing important information about fibril structure and fibrillation processes, to a tool capable to probe also intrinsic properties of amyloid fibrils such as their strength and Youngʹs moduli.