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DNA-magnetic Particle Binding Analysis by Dynamic and Electrophoretic Light Scattering
Published on: November 9, 2017
Viscosity of aqueous DNA solutions determined using dynamic light scattering
Emma L Gilroy1, Matthew R Hicks, David J Smith
1Department of Chemistry and Warwick Centre for Analytical Science, University of Warwick, Coventry, CV4 7AL, UK.
The Analyst
|August 27, 2011
Summary
A new method uses dynamic light scattering (DLS) to accurately measure liquid viscosity using known particle sizes. This technique is more precise than traditional viscometers for small aqueous samples.
Area of Science:
- Physical Chemistry
- Materials Science
- Biophysics
Background:
- Dynamic viscosity is crucial for understanding liquid behavior and flow.
- Accurate micro-litre scale viscosity measurements are challenging for aqueous solutions, particularly biological samples.
- Traditional dynamic light scattering (DLS) applications determine particle size based on known viscosity.
Purpose of the Study:
- To develop and validate a novel method for measuring dynamic viscosity using DLS.
- To invert the standard DLS protocol to determine viscosity from known particle sizes.
- To assess the accuracy and applicability of DLS for viscosity measurements of aqueous solutions.
Main Methods:
- Utilized dynamic light scattering (DLS) with well-defined particle standards.
- Compared DLS-derived viscosity measurements with a U-tube viscometer for water and DNA solutions.
- Investigated the performance of various particle types (styrene, silica, polystyrene microspheres) under different temperatures (0-100 °C).
Main Results:
- Negatively charged carboxylate polystyrene microspheres enabled accurate viscosity measurements.
- The DLS method demonstrated significantly higher accuracy compared to a U-tube viscometer.
- Accurate viscosity determination was achieved across a wide temperature range (0-100 °C).
- The method requires small sample volumes (40-3000 μL) and allows sample recovery.
Conclusions:
- A novel DLS-based method accurately measures dynamic viscosity in micro-litre volumes.
- This technique offers superior accuracy and temperature versatility over traditional viscometers.
- The findings provide a pathway to improve particle size determination in DLS by incorporating viscosity standards.
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