Project Summary In this proposal we request funds to purchase a LUMICKS C‐Trap® from LUMICKS USA Inc. This is a cutting‐edge instrument combining multi‐trap optical tweezers, multi‐color fluorescence confocal microscopy and multi‐channel microfluidics. The instrument provides extremely precise ways to manipulate single molecules or biomolecular aggregates, while monitoring forces and motions with sub‐pN and sub‐nm resolution, and, at the same time, imaging with single‐molecule resolution. The microfluidic systems allows the user to rapidly vary solution conditions during experiments. This instrument brings a new dimension to the study of biomolecular dynamics and cell biology, that of force, up to now limited to custom‐ designed specialty equipment in very few laboratories worldwide, built and operated by highly trained specialists. The C‐Trap® will support applications ranging from the study of DNA enzymes, cytoskeletal motors, subcellular force transmission, the fusion of virus particles to host cells, the function of mechanosensitive channels, the forces exerted and the signals received by cellular filopodia, cell adhesion, to cellular force fluctuations and reactions to mechanical signals. The C‐Trap® will be housed in the interdisciplinary Duke French Family Science Center, housing parts of the chemistry, biology and physics departments, within the Advanced Light Imaging & Spectroscopy (ALIS) laboratory, and will be managed and maintained by the Light Microscopy Central Facility (LMCF). It will be easily accessible to the initial major and minor user group of 14 PIs from Duke's Trinity School of Arts and Sciences, the Pratt Engineering School and the Duke University Medical School as well as from the School of Medicine of the University of North Carolina and the Department of Physics of North Carolina State University. It will be the only such instrument at Duke University and in the research triangle.