Pukyong National University

Pukyong National University Professor Min-Seok Kwak’s ‘DNA Ultrasound Molecular Switch’ Study Selected as Cover Article for International Journal ‘Chem’

- Technology uses DNA to transmit ultrasonic force and selectively break only targeted molecular bonds

- Enables precise mechanochemical reactions … Expected applications in drug delivery, biosensors, and more

Professor Min-Seok Kwak’s research team in the Department of Chemistry at Pukyong National University has developed a new “DNA ultrasound molecular switch” platform that uses DNA to precisely transmit the mechanical force of ultrasound to specific molecular bonds, enabling selective activation of targeted bonds.

The study uses DNA not as a biomolecule but as a precise molecular tool for transmitting mechanical force. Following its online publication on March 3, the research attracted attention in Korea and abroad and has now been recognized for its academic excellence by being selected as the Cover Article for the September 2026 issue (Vol. 12, No. 9) of Chem, a world-renowned journal in the field of chemistry. Published by Cell Press, Chem is a leading journal covering all areas of chemistry and selects only one study per issue to feature on its cover.

The paper, titled “DNA-mediated force transmission for precise and efficient mechanochemical activation,” lists Dr. Gyu-Rin Kim of Pukyong National University as the first author, with Professor Min-Seok Kwak of Pukyong National University and Professor Andreas Herrmann of RWTH Aachen University in Germany as corresponding authors. Professors Hyun-Wook Kang and Hae-Gyun Lim of the Major of Biomedical Engineering at Pukyong National University also participated as co-researchers.

The research team overcame the limitations of conventional mechanochemical techniques by utilizing the structural properties of the DNA double helix to concentrate the mechanical force generated by ultrasound at specific sites. Experiments showed that the team successfully cleaved specifically designed force-responsive molecular bonds with high selectivity and efficiency without damaging the DNA itself.

In particular, DNA structures longer than 250 base pairs (bp) achieved a cleavage rate of 99.9% at the target site within 15 minutes. In experiments using 1 MHz low-intensity ultrasound under skin-like conditions, the system also consistently achieved more than 80% selective cleavage without DNA damage, demonstrating its potential for applications in actual biological environments.

A key feature of the study is the ability to control the magnitude of transmitted mechanical force by adjusting the length of the DNA. Using PCR, the researchers varied the DNA length from 100 to 1,000 base pairs and found that longer DNA transmitted greater force to the target molecule. These findings provide a foundation for designing molecular-level mechanical reactions by controlling experimental parameters such as ultrasound frequency and DNA length.

The newly developed technology has the potential to be extended to a wide range of biomaterial applications, including ultrasound-triggered drug release systems, biosensors, and mechanically responsive therapeutic materials, as it enables specific molecular bonds to be activated at targeted locations by applying ultrasound externally.

The cover of the September 2026 issue of Chem illustrates the principle behind the study through the metaphor of piloting a submersible. It depicts a researcher turning dials representing ultrasound frequency and DNA length to precisely activate a single targeted molecular bond in an aqueous environment. Against a backdrop of ultrasound operating underwater, the DNA double helix is portrayed as a force-transmission device, while the mechanophore at the center of the DNA represents the target site where the ultrasonic force is concentrated. The cover also visually captures a key feature of the study: the ability to control the mechanochemical activation of a targeted molecular bond by adjusting parameters such as ultrasound frequency and DNA length.

Professor Min-Seok Kwak said, “If conventional polymer-based mechanophores are like hammers that distribute force broadly, this DNA-based mechanophore is more like a surgical scalpel that precisely targets a specific molecular bond. We expect this platform combining ultrasound and DNA to eventually develop into a precision therapeutic technology capable of releasing drugs at the desired location inside the body at the right time.”

The research team plans to further expand the platform by integrating it with various biomaterials, including DNA nanostructures and nanoparticle assemblies, for applications such as ultrasound-activated drug delivery systems, biosensors, and mechanically responsive therapeutic materials.

The study was supported by the Nano and Materials Technology Development Program and the Regional Innovation Leading Research Center Program funded by the Ministry of Science and ICT and the National Research Foundation of Korea. <Pukyong Today>