KAIST

<Professor Jimin Park(Center), Ph.D candidate Tae Kyoung Lee, Ph. D candidate Sang Yeon Oh>

The fixed idea that DNA is only a molecule that stores genetic information is being challenged. KAIST researchers have developed a technology that controls the chemical environment around catalysts at the nanometer scale by designing DNA sequences, the arrangement of A, T, G, and C that make up genetic information. The team has presented a new catalyst platform that can improve hydrogen production efficiency and increase the yield of desired chemical products by designing DNA much like writing a computer program.

KAIST (President Kwang Hyung Lee) announced on the 21st of May that a research team led by Professor Jimin Park of the Department of Chemical and Biomolecular Engineering has developed a core technology that precisely controls the microscopic chemical environment around catalysts by coating the surface of gold nanoparticles, ultrafine gold particles measuring 1–100 nm, with “single-stranded DNA,”a flexible DNA molecule composed of a single strand that can be designed with a desired length and structure and serves as a nano-coating material for controlling the reaction environment.

In electrochemical reactions, which use electricity to drive chemical reactions and are used for hydrogen production or the manufacture of eco-friendly chemicals, performance is determined not only by the catalyst itself but also by the local reaction environment around the catalyst, such as acidity (pH) and ion distribution. However, conventional approaches have relied on special polymer coating materials, plastic-like materials made of long molecular chains, and have faced limitations in precisely designing internal structures at the nanometer scale.

To solve this problem, the research team focused on “single-stranded DNA,” DNA composed of a single strand. DNA carries a negative charge, meaning it can influence the movement of surrounding ions, atoms or molecules with electric charge, and it has the advantage that its length and base sequence can be freely designed. In particular, changing the base sequence allows the internal network structure of DNA to be precisely controlled, making it possible to create a customized nano-coating layer on the catalyst surface.

< Schematic illustration of catalytic interfacial microenvironment regulation using a single-stranded DNA layer >

The research team attached DNA with various base sequences to the surface of gold nanoparticles and analyzed the electrochemical reactions. As a result, they found that the key factor determining catalyst performance was not simply the thickness of the coating layer, but the internal network structure formed according to the DNA base sequence.

This means that even coating layers of the same thickness can create different pathways for the movement of ions needed for reactions, depending on how the internal DNA structure is organized. It is the same principle as traffic flow changing depending on how a road network is designed, even when the roads are the same width.

The team also used real-time surface-enhanced Raman spectroscopy, a technology that uses lasers to analyze the chemical state of molecules in real time, to observe the reaction process. Through this, they directly confirmed that the DNA layer functions as an interfacial layer, a layer that performs a special function at the boundary where two materials meet, by regulating the movement of hydroxide ions (OH⁻) and changing the local pH around the catalyst.

In simple terms, the DNA layer acts like a “traffic control center” around the catalyst, guiding the movement of ions. It helps some ions move more quickly while restricting the movement of others, thereby changing the reaction environment in the desired direction. By observing this process in real time, the researchers proved that DNA is not merely a protective film, but actively regulates the reaction environment.

The team applied this technology to the hydrogen evolution reaction and the glycerol oxidation reaction, which converts glycerol, a byproduct of biodiesel production, into high-value chemicals. As a result, hydrogen production efficiency varied significantly depending on the DNA base sequence, and the selectivity, the proportion of a specific product formed, for glycerate, a material used in cosmetics and pharmaceuticals, also improved. This means that desired reaction outcomes can be achieved simply by adjusting the DNA sequence, without newly creating complex catalyst structures.

< Research image (AI-generated image) >

Professor Jimin Park said, “This study shows that DNA can be used not as a genetic information storage medium, but as a precise nanomaterial that controls electrochemical reactions,” adding, “By designing DNA sequences to control acidity and ion movement on catalyst surfaces, we expect this technology to be broadly applied across carbon-neutral technologies, including hydrogen production and biomass conversion.”

This study was conducted with KAIST Department of Chemical and Biomolecular Engineering doctoral students Sang Yeon Oh and Tae Kyoung Lee as co-first authors, and Professor Jimin Park as the corresponding author. The research was published on May 5 in the internationally renowned Journal of the American Chemical Society.
 ※ Paper title: “Programmable Single-Stranded DNA Layers as Modulators of Nanoscale pH at Electrocatalytic Interfaces,” DOI: 10.1021/jacs.6c02995
 ※ Author information: Sang Yeon Oh and Tae Kyoung Lee (KAIST, co-first authors), Jaeyeon Jun, Jinse Woo, Changho Lee, Yongha Kim (KAIST, co-authors), and Jimin Park (KAIST, corresponding author)

This research was supported by the National Research Foundation of Korea’s Outstanding Young Scientist Program , Global Matching Program , and Young Researcher Infrastructure Support Program.