A straightforward process manipulates the dramatic morphological changes of DNA rolling circle amplification products

Area of Science:

• Biotechnology and Biomaterials Science
• Molecular Biology and Genetics

Background:

• Rolling circle amplification (RCA) is a key technique for synthesizing DNA nanostructures, including nanoparticles and macro-hydrogels.
• Existing RCA methods for macro-hydrogel synthesis often involve complex strategies like oscillation-promoted entanglement and multi-round amplification.

Purpose of the Study:

• To develop a simplified and effective method for controlling the morphology of RCA products, transitioning from nanoparticles to 3D hydrogels.
• To introduce a novel cold treatment step for circular DNA templates to enhance DNA chain entanglement during RCA.

Main Methods:

• A straightforward method involving a cold treatment of the circular DNA template before phi29 DNA polymerase-mediated elongation.
• Utilized rolling circle amplification (RCA) with a single round and a single type of circular DNA.
• Eliminated the need for oscillation during amplification, simplifying the process.

Main Results:

• Successfully manipulated RCA product morphology from nanoparticles to 3D hydrogels using the cold treatment step.
• The cold treatment induced minor aggregation of the circular DNA template, significantly enhancing DNA chain entanglement.
• Achieved milder reaction conditions, a shorter reaction time, and a more straightforward synthesis system compared to existing methods.

Conclusions:

• The proposed cold treatment method offers a simplified, efficient, and milder approach to synthesizing DNA macro-hydrogels via RCA.
• This technique streamlines the production of DNA hydrogels, making it more accessible and less resource-intensive.
• The method provides a valuable alternative for fabricating DNA-based materials with controlled morphology.