title: Optical trapping of a single protein.
abstract: We experimentally demonstrate the optical trapping of a single bovine serum albumin (BSA) molecule that has a hydrodynamic radius of 3.4 nm, using a double-nanohole in an Au film. The strong optical force in the trap not only stably traps the protein molecule but also unfolds it. The unfolding of the BSA is confirmed by experiments with changing optical power and with changing solution pH. The detection of the trapping event has a signal-to-noise ratio of 33, which shows that the setup is extremely sensitive to detect the presence of a protein, even at the single molecule level.
authors.affiliation: Department of Electrical and Computer Engineering, University of Victoria, Victoria, British Columbia V8W 3P6, Canada.
authors.forename: Yuanjie
authors.initials: Y
authors.lastname: Pang
authors.forename: Reuven
authors.initials: R
authors.lastname: Gordon
mesh_terms: D052898:Optical Tweezers; D011489:Protein Denaturation; D017510:Protein Folding; D012710:Serum Albumin, Bovine / Q000302:isolation & purification* / Q000648:ultrastructure*
chemical_list: D012710:Serum Albumin, Bovine