Mechanical systems are composed of force-generating motors, force sensors, and load-bearing structures. Macro- and micro-scale mechanical systems have revolutionized human civilization, and nanoscale mechanical systems have similar potential. DNA nanotechnology, a unique platform for the self-assembly of complex nanostructures, offers unprecedented capacity to design the components of nanoscale mechanical systems. Today, mechanical DNA devices are playing increasingly critical roles in molecular biophysics, immunology, regenerative medicine, materials science, and nanorobotics. For example, in cell biology, DNA-based force sensors are indispensable to the study of force-transmitting surface receptors on live cells. Engineered DNA “handles” are increasingly common in single molecule force spectroscopy (SMFS) techniques. DNA mechanotechnology capabilities are even starting to rival those of conventional SMFS techniques by offering instrument-free approaches to mechanically clamp molecules at specific forces. Very recently, DNA-based molecular robots have been shown to generate forces and carry cargo to defined locations.

DNA-based devices that are designed to sense, transmit, and/or generate piconewton (pN)-scale forces are broadly referred to as DNA mechanotechnology. Different types of DNA mechanotechnology have been demonstrated across a wide array of disciplines. This Methods Collection will highlight a diversity of techniques that use DNA mechanotechnology to sense, transmit, and generate piconewton-scale forces. Someday, fully functional nanoscale mechanical systems may be created by integrating all three of these types of DNA mechanotechnology. One aim of this special issue is to help facilitate such integration by housing diverse methodologies in a common collection.