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Use of Dual Optical Tweezers and Microfluidics for Single-Molecule Studies
Published on: November 18, 2022
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Combined Magnetic Tweezers and Micro-mirror Total Internal Reflection Fluorescence Microscope for Single-Molecule
1Laboratory of Single Molecule Biophysics, National Heart, Lung, and Blood Institute, National Institutes of Health, Building 50, Room 3517, 50 South Drive, Bethesda, 20892, MD, USA.
Methods in Molecular Biology (Clifton, N.J.)
|September 24, 2017
Summary
This study integrates magnetic tweezers with microscopy for simultaneous single-molecule visualization and mechanical manipulation. A novel calibration method for evanescent wave penetration depth is presented, enhancing nucleic acid studies.
Area of Science:
- Biophysics
- Molecular Biology
- Microscopy
Background:
- Magnetic tweezers are a key technique for single-molecule studies.
- Nucleic acids and molecular motors are common subjects.
- Simultaneous visualization and manipulation are desired.
Purpose of the Study:
- To combine magnetic tweezers with total internal reflection microscopy.
- To enable simultaneous single-molecule visualization and mechanical manipulation.
- To develop a method for calibrating evanescent wave penetration depth.
Main Methods:
- Integration of micro-mirror-based total internal reflection microscopy with magnetic tweezers.
- DNA supercoiling using a fluorescent nanodiamond-labeled magnetic bead for calibration.
- Surface-immobilized fluorescent nanodiamonds for complementary calibration.
Main Results:
- Achieved simultaneous visualization and mechanical manipulation of single molecules.
- Developed a simple DNA supercoiling-based method for evanescent wave penetration depth calibration.
- Validated the calibration method with a complementary approach.
Conclusions:
- The combined technique offers enhanced capabilities for single-molecule biophysics.
- The novel calibration method simplifies and improves accuracy in evanescent wave measurements.
- This approach advances the study of nucleic acid dynamics and molecular motors.
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