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Updated: Dec 12, 2025
06:55
Simple Bulk Readout of Digital Nucleic Acid Quantification Assays
Published on: September 24, 2015
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Single molecule mass photometry of nucleic acids
Yiwen Li1, Weston B Struwe1, Philipp Kukura1
1Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, UK.
Nucleic Acids Research
|August 7, 2020
Summary
Mass photometry, a technique for measuring protein mass, can now accurately detect and quantify nucleic acids. This label-free method offers rapid, single-molecule analysis for DNA characterization.
Area of Science:
- Biophysics
- Molecular Biology
- Analytical Chemistry
Background:
- Mass photometry is an emerging technique for measuring the mass of individual proteins in solution.
- Existing methods for nucleic acid analysis often require labeling or separation steps.
Purpose of the Study:
- To demonstrate the applicability of mass photometry for nucleic acid analysis.
- To establish mass photometry as a rapid, label-free method for nucleic acid detection and quantification.
Main Methods:
- Utilizing mass photometry to measure individual nucleic acid molecules.
- Analyzing a dsDNA ladder to correlate imaging contrast with DNA length.
- Quantifying nucleic acid concentration by counting individual molecules.
Main Results:
- Mass photometry accurately detects and quantifies nucleic acids using sub-picomole amounts.
- A linear relationship was observed between DNA length (up to 1200 bp) and imaging contrast.
- DNA length can be quantified with up to 2 bp accuracy.
Conclusions:
- Mass photometry is a versatile, label-free technique applicable to nucleic acids.
- This method provides accurate, rapid, and sensitive single-molecule analysis for DNA.
- Mass photometry complements existing DNA characterization techniques.
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