Light-Responsive Polymer Particles as Force Clamps for the Mechanical Unfolding of Target Molecules

• Type of Material: Article
• Authors: Hanquan Su, Emory University; Zheng Liu, Emory University; Yang Liu, Emory University; Victor Pui-Yan Ma, Emory University; Aaron Blanchard, Georgia Institute of Technology; Jing Zhao, Emory University; Kornelia Galior, Emory University; Richard Dyer, Emory University; Khalid Salaita, Emory University
• Language: English
• Date: 2018-04-01
• Publisher: American Chemical Society
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2018 American Chemical Society.
• Final Published Version (URL): http://dx.doi.org/10.1021/acs.nanolett.8b00459
• Title of Journal or Parent Work: Nano Letters
• ISSN: 1530-6984
• Volume: 18
• Issue: 4
• Start Page: 2630
• End Page: 2636
• Grant/Funding Information: The work was supported by grants from the NSF CAREER Award (1350829); the DARPA BTO (HR0011-16-2-0011) and the NIH (R01-GM097399).; V.P.-Y.M. is supported by the National Cancer Institute Predoctoral to Postdoctoral Fellow Transition Award (F99CA223074).; A.T.B. is supported by the NSF Graduate Research Fellowship Program (1444932).; This project was supported in part by the Robert P. Apkarian Integrated Electron Microscopy Core.
• Keywords: Physics; NANOROD; responsive materials; MAGNETIC TWEEZERS; DNA; Technology; Physics, Condensed Matter; Nanoscience & Nanotechnology; Materials Science; Science & Technology; Core-shell particle; gold nanoparticles; SINGLE; TENSION PROBES; DNA unfolding; Physical Sciences; DYNAMICS; Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary; KINETICS; TITIN; Science & Technology - Other Topics; Chemistry; PROTEINS; force spectroscopy; Physics, Applied; SPECTROSCOPY
• Research Categories: Chemistry, General; Engineering, Biomedical

Abstract

Single-molecule force spectroscopy techniques are powerful tools for investigating the mechanical unfolding of biomolecules. However, they are limited in throughput and require dedicated instrumentation. Here, we report a force-generating particle that can unfold target molecules on-demand. The particle consists of a plasmonic nanorod core encapsulated with a thermoresponsive polymer shell. Optical heating of the nanorod leads to rapid collapse of the polymer, thus transducing light into mechanical work to unfold target molecules. The illumination tunes the duration and degree of particle collapse, thus controlling the lifetime and magnitude of applied forces. Single-molecule fluorescence imaging showed reproducible mechanical unfolding of DNA hairpins. We also demonstrate the triggering of 50 different particles in <1 min, exceeding the speed of conventional atomic force microscopy. The polymer force clamp represents a facile and bottom-up approach to force manipulation.