title: A molecular tuning fork in single-molecule mechanochemical sensing.
abstract: The separate arrangement of target recognition and signal transduction in conventional biosensors often compromises the real-time response and can introduce additional noise. To address these issues, we combined analyte recognition and signal reporting by mechanochemical coupling in a single-molecule DNA template. We incorporated a DNA hairpin as a mechanophore in the template, which, under a specific force, undergoes stochastic transitions between folded and unfolded hairpin structures (mechanoescence). Reminiscent of a tuning fork that vibrates at a fixed frequency, the device was classified as a molecular tuning fork (MTF). By monitoring the lifetime of the folded and unfolded hairpins with equal populations, we were able to differentiate between the mono- and bivalent binding modes during individual antibody-antigen binding events. We anticipate these mechanospectroscopic concepts and methods will be instrumental for the development of novel bioanalyses.
authors.affiliation: Department of Chemistry and Biochemistry, Kent State University, Kent, OH 44242 (USA).
authors.forename: Shankar
authors.initials: S
authors.lastname: Mandal
authors.affiliation: Department of Chemistry and Biochemistry, Kent State University, Kent, OH 44242 (USA).
authors.forename: Deepak
authors.initials: D
authors.lastname: Koirala
authors.affiliation: Department of Chemistry and Biochemistry, Kent State University, Kent, OH 44242 (USA).
authors.forename: Sangeetha
authors.initials: S
authors.lastname: Selvam
authors.affiliation: Department of Chemistry and Biochemistry, Kent State University, Kent, OH 44242 (USA).
authors.forename: Chiran
authors.initials: C
authors.lastname: Ghimire
authors.affiliation: Department of Chemistry and Biochemistry, Kent State University, Kent, OH 44242 (USA). hmao@kent.edu.
authors.forename: Hanbin
authors.initials: H
authors.lastname: Mao
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D004247:DNA / Q000737:chemistry*; D018625:Microscopy, Atomic Force / Q000295:instrumentation* / Q000379:methods; D014732:Vibration
chemical_list: D004247:DNA
keywords: DNA structures; biosensors; mechanochemical sensing; optical tweezers; single-molecule techniques