Related Experiment Video
Updated: May 17, 2026

DNA-Tethered RNA Polymerase for Programmable In vitro Transcription and Molecular Computation
Published on: December 29, 2021
Thermodynamically unfavorable DNA hybridizations can be made to occur by a water to ice phase change
Abhichart Krissanaprasit1, Cristian Guajardo, Mithran Somasundrum
1School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, Bangkhuntien Campus, Bangkok 10150, Thailand.
Abstract:
In an apparent contradiction to Debye-Hückel theory, it was possible to hybridize DNA in solutions of Milli-Q water (resistivity>18MΩcm(-1)) containing no added ions. This was demonstrated by hybridizing four bi-complementary DNA sequences to form an 'X' shape, as indicated by acrylamide gel electrophoresis. The requirement for hybridization was that a water-to-ice phase change should occur. Comparative experiments, using freezing by liquid nitrogen and thawing at different temperatures, showed that hybridization could take place during either the freezing or thawing process provided either was slow enough. We speculate that the low solubility of DNA in ice creates liquid inclusions of extremely high DNA and counter-ion concentration prior to complete freezing, and that hence in these inclusions hybridization was actually in accordance with Debye-Hückel theory.
Related Concept Videos
Phase Transitions: Melting and Freezing
States of Water
Water freezes when the intermolecular forces are greater than the kinetic energy. Unlike most other substances, water is less dense in its solid state than in its liquid state. This is because each water molecule can form...
Heating and Cooling Curves
For instance, the addition of heat raises the temperature of a solid; the amount of heat absorbed depends on the heat capacity of the solid (q = mcsolidΔT). According to thermochemistry, the relation between the amount of heat absorbed or released by a substance, q, and its...
DNA Topoisomerases
Types and Mechanism of action
Topoisomerases are divided into two main types. Type I...
Aldehydes and Ketones with Water: Hydrate Formation
The formation of hydrates is a reversible reaction. Hydrate formation is influenced by steric and electronic factors accompanying the alkyl substituents on the carbonyl group: The rate of hydrate formation increases with a decrease in the number of alkyl groups attached to the carbonyl carbon. Hence,...
Phase Transitions

