Research

Wealthier and More Populated Metropolitan Areas Respond More Strongly to Early Drought News by Saving Water

[POSTECH Professor Jonghun Kam’s research team, in collaboration with KRIHS, NDMI, Stanford University, and the National University of Singapore (NUS), presents AI-based, region-specific water conservation scenarios using drought news data] As climate change increases the risk of severe droughts, water resources management is an urgent challenge. Drought develops slowly, which makes the public aware of the ongoing drought. Governments rely on the media to communicate drought risks and encourage water conservation. However, it has remained unclear how much drought-related news actually contributes to water-saving behavior in different regions. A research team led by Professor Jonghun Kam at POSTECH used explainable artificial intelligence (XAI) to analyze how drought-related news coverage influenced household water conservation during the 2022-2023 drought in southwestern Korea. The study, titled “Spatiotemporal and Economic Impacts of Media on Water Conservation during Drought: An Explainable AI Approach,” was published in Water Resources Research, a leading international journal in water resources. Traditional hydrological models mainly focus on physical drought conditions, such as rainfall deficits and dam storage levels. However, drought response often depends on social factors, including public awareness, media coverage, and regional socioeconomic conditions. To capture interactions between natural and social systems, the research team developed AI models using household water use data, drought indices, dam storage levels, temperature, and drought-related news articles. The team first calculated monthly water conservation rates by comparing actual household water use with average water use in the same month over the previous five years. The results showed that metropolitan areas with higher population density and income levels tended to show stronger voluntary water conservation during drought. In Gwangju Metropolitan City, water conservation rates increased by up to about 10%, while smaller cities and rural areas in Jeollanam-do showed increases of only about 3%. Among several AI models, the N-BEATS model predicted monthly water conservation rates with more than 73% accuracy in both metropolitan and smaller regions. The AI-based scenario analysis showed that when drought-related news coverage increased during the early and caution stages of drought, household water conservation in Gwangju increased by about 14 percentage points compared with the baseline. This corresponded to approximately USD 0.82 million in reduced tap water production costs. In contrast, the same increase in news coverage led to only about four percentage point increase in smaller cities and rural areas, equivalent to approximately USD 0.3 million in cost savings. This suggests that the impact of media coverage differs by region. Metropolitan households may have flexible water use and respond sensitively to drought information, while rural households may have limited room to further reduce basic domestic water consumption. The study also found that the timing of media communication matters. News coverage had a stronger effect during the early and caution stages of drought, before conditions became severe. Once drought entered the alert stage, public concern and water conservation were already relatively high, leaving room for additional savings limited. This suggests that drought communication is effective when delivered early, rather than after the crisis has intensified. Existing drought contingency policies are from a top-bottom approach applying uniform water conservation targets across drought-affected regions. This study provides a scientific basis for setting region-specific water-saving targets by considering both regional conditions and drought stages. The first author, Eunmi Lee of POSTECH, said, “By using explainable AI, we are able to quantitatively reveal the hidden link between media coverage as a social factor and actual public water-saving behavior.” She added, “We hope that AI-based water resources research integrating environmental and social data will provide actionable information for developing effective, region-specific drought response strategies in climate crisis.” This work was supported by a National Research Foundation of Korea (NRF) grant funded by the Ministry of Science and ICT (MSIT) (No. RS-2026-25470040) and by a grant (2022-MOIS63-001 (RS-2022-ND641011)) for Cooperative Research Method and Safety Management Technology in National Disaster, funded by the Ministry of Interior and Safety (MOIS, Korea) ▶️ DOI: https://doi.org/10.1029/2025WR042406

"Semiconductors Enter the Era of Skyscrapers": Stacking Chips Like High-Rise Buildings to Boost Performance

[POSTECH Demonstrates Stable Stacking of More Than 10 Ultrathin Si Chips, Achieving Four Times Higher Integration Density Than Commercial HBM] A Korean research team has developed a technology that enables the stable stacking of more than ten ultrathin semiconductor chips, each only one-fifth the thickness of a human hair. A research team led by Prof. Seok Kim and integrated Ph.D. student Uhyeon Kim from the Department of Mechanical Engineering at POSTECH, together with Dr. Hohyun Keum of the Korea Institute of Industrial Technology, successfully achieved an integration density approximately four times higher than that of commercial high-bandwidth memory (HBM) through a novel process that simultaneously transfers chips and forms metallic interconnections. The study was published in the international multidisciplinary engineering journal Results in Engineering. AI services such as ChatGPT, image-generation AI, and autonomous vehicles share one common requirement: they must process enormous amounts of data at extremely high speeds. While electronic devices continue to become thinner, semiconductor performance continues to improve because chips are no longer expanded laterally but stacked vertically. This is analogous to constructing high-rise apartment buildings instead of single-family homes when urban land becomes scarce. High-Bandwidth Memory (HBM), a key technology that determines the performance of AI accelerators, is built by vertically stacking multiple memory chips, making the ability to reliably stack a large number of chips a critical challenge. The difficulty lies in handling ultrathin chips. As chip thickness decreases below several tens of micrometers (μm), becoming thinner than a human hair, chips become increasingly susceptible to bending, warping, and fracture. Much like a stack of thick cardboard remains flat while stacked layers of delicate rice paper easily wrinkle and become misaligned, the challenge becomes more severe as the number of stacked layers increases. Conventional semiconductor packaging processes primarily rely on flip-chip bonding and carrier-wafer-based grinding processes. However, flip-chip bonding requires highly precise pneumatic nozzle design and process control, while grinding-based approaches often suffer from handling damage and warpage. These issues become significantly more pronounced when chip thickness falls below several tens of micrometers. To address these limitations, the researchers leveraged the inherent stability of transfer printing technology, demonstrating both reliable integration and the fabrication of chips with thicknesses in the 10-micrometer range. To overcome these challenges, the team combined two technologies into a single process platform: Transfer Printing, which precisely places chips at desired locations, and In-situ Bonding, which forms metallic bonds simultaneously during chip transfer. This integrated approach allows chip transfer, placement, and electrical interconnection to be completed in a single process. To validate the new process, the researchers fabricated ultrathin silicon chips approximately 14 μm thick. Each chip incorporated both vertical electrical signal pathways and lateral redistribution wiring, making the structure highly suitable for multilayer integration. Using the developed process, the team successfully stacked more than ten ultrathin chips under low-temperature (below 180°C) and low-pressure (below 20 kPa) conditions. Even after repeated stacking, interlayer alignment errors remained extremely small, and structural warpage was significantly suppressed. The achieved integration density—defined as the number of stacked layers relative to total package thickness—was approximately four times greater than that of conventional 12-layer HBM structures. In other words, substantially more chips can be accommodated within the same vertical height. Commercialization of this technology could dramatically increase the number of chips integrated within a given space, enabling significant improvements in AI semiconductor performance. Furthermore, the technology has potential applications beyond memory devices, including chiplet-based heterogeneous integration and next-generation micro-LED displays, suggesting a broad technological impact. Prof. Seok Kim of POSTECH stated, "By we achieved an integration density approximately four times higher than existing HBM technologies, we expect this technology to become a key enabling technology for future high-performance AI semiconductors and next-generation memory systems.“ Dr. Hohyun Keum of KITECH noted, "Micrometer-scale ultra-precise alignment and bonding technologies developed in this work could be widely applied to next-generation semiconductor and display manufacturing.“ This research was supported by the National Research Foundation (NRF) of Korea through the PIM AI Semiconductor Core Technology Development Program (Device) and the Mid-Career Researcher Program. ▶️ DOI: https://doi.org/10.1016/j.rineng.2026.111194

The Gap Between Forecasts and Reality Changes Public Emotions During Disasters

[POSTECH Research Team Led by Professor Jonghun Kam Analyzes the Impact of Disaster Forecast Uncertainty on Public Emotions] What happens when weather forecasts do not match reality? How do the public emotionally respond when a disaster unfolds differently from what they expected? A research team led by Professor Jonghun Kam and Kiru Kim from the Department of Environmental Engineering at POSTECH investigated how forecast error types influenced public emotion during the landfall of Typhoon Khanun. Using an artificial intelligence (AI), Natural Language Processing (NPL), the researchers found that different types of forecast error (e.g., over/underestimation) triggered distinct emotional responses among the public. The study has been published in GeoHealth. Weather forecasts are essential for disaster preparedness, but they are inherently uncertain. During extreme weather events such as typhoons, forecasts may either overestimate rainfall that never occurs or underestimate rainfall that turns out to be severe. The research team focused on how these mismatches between expectation and reality affect public perceptions and emotional responses before and after the landfall of Typhoon Khanun. The researchers assessed the Korean Meteorological Administration’s prediction skill of Typhoon Khanun, which crossed the Korean Peninsula in August 2023 against observed rainfall records from 613 weather stations. They also analyzed more than 43,000 online posts from NAVER Report Talk using an AI-based natural language processing model. The results revealed clear spatial differences in forecast performance. Forecasts tended to underestimate heavy rainfall in the eastern and southeastern regions of the Korean Peninusla while overestimating rainfall in the western and metropolitan areas. In regions where rainfall was overestimated, anxiety, worry, and fatigue became dominant emotion types in online discourses while the public from the regions with underestimated rainfall showed a high level of certain emotion types like confusion, embarrassment, and sadness. The researchers also examined changes in regional emotion. In the eastern and southeastern regions, where actual rainfall exceeded forecast amounts, online discussions frequently expressed confusion, uncertainty, and anxiety as Typhoon Khanun passed by the Korean Peninsula. The western and metropolitan regions, where rainfall forecasts were higher than observed rainfall, showed dominant emotions of worry and concern, followed by increasing a level of emotion types, relief and reassurance, as the typhoon passed. These findings suggest that people respond not only to the disaster itself but also to the gap between what they expected and what they actually experienced. Overall, approximately 55% of all online discourses expressed negative emotions, with anxiety and worry being the most common. The researchers also found that information-seeking activities peaked before the typhoon’s landfall, whereas online reporting and experience sharing surged during the event itself. This indicates that the public shift from passive information consumers to active information providers as disaster impacts become more immediate. The findings demonstrate that forecast accuracy is not only a technical issue but also an important factor influencing public perception and emotional well-being. More importantly, the study highlights that the mismatch between anticipated risk and experienced reality plays a critical role in shaping public emotions and their perceived risk during disasters. The researchers suggest that communicating forecast uncertainty more effectively could improve public trust and reduce emotional distress during future extreme weather events. Kiru Kim, the lead author, noted, “This study demonstrates that in disaster situations, it is important not only to improve forecast accuracy but also to develop risk communication strategies that effectively convey uncertainty to the public.” Professor Jonghun Kam said, “This study demonstrates how AI can be used to analyze large-scale public discourse and monitor the emotional impacts of forecast errors. The findings provide new insights into how to develop effective risk communication strategies during landfalling typhoons and other natural disasters.” ▶️ DOI: https://doi.org/10.1029/2026GH001837

Development of High-Performance, Air- and Thermally-Stable Tin Perovskite Transistors through Volatile Surface Coordinat

[Professor Yong-Young Noh's team solves one of the semiconductor industry's "10 Future Grand Challenges" by achieving record-breaking performance and stability in p-type perovskite transistors] [First-ever study on perovskite transistors published in Nature] Air is absolutely essential for human life, but for certain semiconductors, it is a deadly poison. The moment these materials come into contact with air, unreacted tin ions on their surface oxidize, creating defects that destroy the device. Now, a research team led by Professor Yong-Young Noh at POSTECH has solved this long-standing problem and published a next-generation semiconductor with enhanced performance and stability in Nature. The study, led by Professor Yong-Young Noh's team at POSTECH (Dr. Geonwoong Park, PhD candidate Dong-Hyun Lee, and Dr. Youjin Reo), in collaboration with Professor Ji-Sang Park's team at Sungkyunkwan University and the teams of Professor Ao Liu and Professor Huihui Zhu at the University of Electronic Science and Technology of China (UESTC), was published on July 1 (local time). It is the world's first paper on perovskite transistors to appear in Nature, a milestone that effectively inaugurates a new field of research. Smartphones contain countless transistors. A "transistor" is a tiny switch that turns electrical signals on and off, and comes in two types: "n-type," which carries electrons, and "p-type," which carries holes (the vacancies left behind when electrons leave). Building a high-performance, low-power semiconductor requires a balance between the two types — but improving p-type transistor performance has proven especially difficult, so much so that Korea's Ministry of Science and ICT named it one of the "10 Future Grand Challenges in Semiconductors.“ Tin-based perovskites have drawn attention as a strong candidate for solving this challenge. Holes flow smoothly through the material, and its performance can rival that of low-temperature polycrystalline silicon (LTPS) or oxide semiconductors, which currently drive memory chips and high-performance displays. The problem is that it is extremely vulnerable to air: unreacted tin ions (Sn2+) left on the surface oxidize on contact with air, generating a host of defects that block charge flow — causing the semiconductor's performance to collapse almost instantly. The research team's solution is a strategy called "Volatile Surface Reconstruction." When the surface of a cesium-tin-iodide (CsSnI3) semiconductor was treated with potassium acetate (KAc), the unreacted tin ions responsible for the performance loss were converted into a volatile compound, tin acetate (Sn(Ac)2), which simply volatilized. What's more, potassium iodide (KI) naturally formed in the spots left behind by the departing tin ions, creating a "self-protective layer" that shields the semiconductor from the outside environment. It was a killing two birds –with one stone solution: the troublemaker was evaporated away, and the gap it left behind was sealed with a protective layer. As a result, the threshold voltage needed to switch the device on was lowered, hole mobility exceeded 50 cm2/V·s, and the on/off current ratio — which reflects the difference between the on and off states — reached over 100 million (108), achieving world-class performance for a p-type perovskite transistor. What stands out most is its air stability. While conventional devices broke down within minutes in open air, the new device held up for more than four hours. It also retained its initial performance for over a month even under accelerated thermal degradation testing at 100 °C. The high environmental and thermal stability the team achieved is expected to serve as a foundational technology for processes that stack devices in multiple layers and fabricate them over large areas. Professor Yong-Young Noh said, "Thanks to Samsung Display and the Ministry of Science and ICT, who believed in a topic many considered impossible and provided steady support over the past six years, we were able to achieve the world's first report on perovskite transistors in Nature." He added, "Going forward, this technology is expected to serve as a core technology across a wide range of future electronics applications — including vertically stacked DRAM memory devices for AI-driven computation, next-generation display driver circuits, wearable devices, and highly integrated semiconductor devices." ▶️ DOI: https://doi.org/10.1038/s41586-026-10714-1

"The Protein Factory Worker Became a Switch" New Gene Circuit Technology Enables Cells to Make Their Own Decisions

[POSTECH research team led by Prof. Jongmin Kim develops 'RATEX,' an RNA circuit capable of complex computation inside living cells] The molecular machinery that normally works on building proteins inside cells has now taken on a new role as a "switch." A research team at POSTECH has developed a new 'RNA-based smart gene circuit' platform that can simultaneously read multiple signals inside a cell, make its own decisions, and autonomously generate programmed responses. This represents a step beyond simple genetic manipulation toward an era in which cells themselves function as "living computers." The technology, named 'RATEX' (Ribosome-Assisted Transcriptional EXpression controller), was developed by Prof. Jongmin Kim, Dr. Hansol Kang, and graduate students Hyunseop Goh and Chaeri Kim from the Department of Life Sciences at POSTECH. The results were recently published in the international chemistry journal Angewandte Chemie. Cells use genetic information to build proteins and elicit cellular responses in two major steps. First, the information encoded in DNA is copied into RNA in a process called "transcription." Then, that RNA is read to build proteins in a process called "translation." Synthetic RNA-based gene circuits have focused on control strategy at one or the other stage of signal processing, where signal sensing and processing were largely confined to a single level. In reality, however, cells must integrate numerous molecular signals at multiple regulatory levels to make decisions much like a vehicle at a complex intersection where multiple traffic lights flash simultaneously, Current genetic circuit designs often faced challenges to handle this increased level of computational complexity. To address this bottleneck, the research team turned their attention to ribosome, the molecular machine responsible for building proteins. Ribosomes normally read RNA and produce proteins, but also respond to molecular signatures encoded within RNA transcript. By co-opting and enhancing the signal processing capability of ribosome in combination with specific RNA motifs, the team engineered a system where ribosomes “pause” at specific locations on a gene when certain conditions are met, which in turn determines whether gene expression proceeds. In effect, the ribosome has been promoted from a mere production machine to a "switch." This architecture, where the computational result at the translation stage immediately dictates whether transcription occurs, termed Translation-to-Transcription Converter (TTC), forms the basic building block for the RATEX platform. This design strategy enables repurposing available library of synthetic translational logic switches to directly control the transcription process. This novel approach allowed to overcome the previous design limitations and dramatically improved scalability. The research team demonstrated gene regulatory capacity of up to 1,492-fold and implemented complex logic circuits capable of simultaneously processing up to six RNA signals. The team also created diverse hybrid logic circuits capable of simultaneously recognizing both RNA signals and metabolites such as amino acids and vitamins. Cells now possess advanced signal processing capability where they can "compute" multiple types of molecular information at once. Beyond simple logical control of gene expression, the team combined the RATEX platform with CRISPR gene regulation and synthetic membraneless organelles, thereby altering cell morphology and reorganizing intracellular structures only when all specified conditions were satisfied. This flexibility in design further demonstrated that cells can be precisely "programmed." This platform technology promises to provide a novel design paradigm for applications in diverse fields. For instance, RATEX could provide a framework to develop smart therapeutics that detect cancer-specific molecular signatures and produce treatment compounds in situ, and environmental biosensors that respond only upon encountering particular combinations of pollutants. Prof. Jongmin Kim stated, "The key contribution of this research is seamlessly integrating the sophisticated cellular decision-making at the translation stage for transcriptional control." He added, "The ability to integrate and process different types of signals -- such as RNA and metabolites -- within a single RNA transcript represents a new design paradigm to further scale up synthetic biological circuits." This research was supported by the National Research Foundation of Korea (NRF) Basic Research Program funded by the Ministry of Science and ICT; the POSTECH Basic Science Research Institute; the National Research Facilities and Equipment Center of the Korea Basic Science Institute; the Gyeongbuk Technopark FoodTech R&D Center Development and Support Program; the High Value-added Food Technology Development Program funded by the Ministry of Agriculture, Food and Rural Affairs; the Korea Health Industry Development Institute (KHIDI) Health Technology R&D Project funded by the Ministry of Health and Welfare; and the Basic Science Research Program of the NRF funded by the Ministry of Education. ▶️ DOI: https://doi.org/10.1002/anie.202520600

Focusing Underwater Sound with a Lens 40% Lighter Than Conventional Designs

[POSTECH-KRISO team develops an ultra-light underwater lens for broadband low-frequency sound focusing] In the underwater world, sound is the primary means of communication, as light quickly fades. A Korean research team has developed an underwater acoustic lens capable of focusing sound precisely at a desired point while reducing weight by about 40% compared with conventional designs. The research was led by Professor Junsuk Rho of Pohang University of Science and Technology, together with Ph.D. candidate Beomseok Oh, in collaboration with Dr. Sea-Moon Kim of the Korea Research Institute of Ships and Ocean Engineering. The findings, expected to open new possibilities for underwater communication, marine environmental monitoring, and acoustic energy transfer, were recently published in the international journal, Journal of Sound and Vibration. In movies, submarine operators are often seen wearing headphones, listening carefully to the sounds of the ocean. This is not far from reality. Light disappears rapidly after traveling only a few hundred meters underwater, whereas sound can propagate over thousands of kilometers. In the ocean, sound is not merely a wave— it is virtually the only language available. The challenge is that focusing underwater sound at a desired location is far more difficult than it may seem. Conventional acoustic lenses use bulky solid structures to bend and concentrate sound. However, low-frequency sound has long wavelengths, meaning that lenses designed to control low-frequency sound must become excessively large and heavy. To overcome this limitation, the research team replaced fully solid scatterers with cavity-based metamaterial structures that allow water to pass through. Each cavity functions like a resonator, strongly interacting with sound at specific frequencies. By strategically arranging these “sound resonance chambers,” the team created a lens capable of focusing underwater sound into a single focal point. The team fabricated a 240 mm-diameter lens using metal 3D printing and demonstrated stable broadband focusing of low-frequency underwater sound in the 20-35 kHz range. Under the same 280 mm-diameter design condition, the proposed cavity-based lens reduced the weight from 27.5 kg to 17.2 kg, achieving a reduction of approximately 40% compared with a conventional solid lens. The researchers also observed a phenomenon known as Willis coupling1), which caused sound to reflect differently depending on its incident direction. This asymmetric response suggests that the lens can do more than simply focus sound; it may also enable precise control over the directionality of acoustic waves. The team expects this technology to be applied to a wide range of applications, including underwater sensor networks, underwater communication systems, and wireless acoustic energy transfer. In future underwater Internet of Things (IoT) environments, where distributed sensors exchange information through sound, this lens could serve as a key component for enhancing signal clarity and reliability. Professor Junsuk Rho, who led the study, said, “This work addresses three major challenges in underwater acoustic devices at once: low-frequency operation, broadband performance, and lightweight design.” Dr. Sea-Moon Kim added, “This study is significant because it presents a new design paradigm for three-dimensional low-frequency underwater acoustic lenses.” ▶️ DOI: https://doi.org/10.1016/j.jsv.2026.119919 1. Willis coupling: An acoustic coupling phenomenon in which sound pressure and particle velocity are interlinked, causing acoustic waves to reflect or transmit differently depending on the forward or backward propagation direction.

“Just Remove the Water?” The Real Culprit Behind Battery Failure Revealed

[POSTECH Identifies True Cause of Prussian Blue Performance Loss — Surface Oxidation, Not Crystal Water, Is the Key Factor] Like a delicate fabric that becomes damaged during drying, a promising next-generation battery material has faced an unexpected challenge: removing water to improve performance can actually shorten battery life. Now, a Korean research team has identified surface oxidation occurring during the dehydration process as the true cause of performance degradation and developed a new dehydration progress to overcome it. A research team led by Professor Changshin Jo from the Department of Battery Engineering and the Department of Chemical Engineering at POSTECH, together with Ph.D. candidate Seunghye Jang from the Department of Battery Engineering, recently published their findings in Advanced Materials, a world-leading journals in materials science. As the markets for electric vehicles (EVs) and energy storage systems (ESSs) continue to expand, competition for battery raw materials is intensifying. Sodium-ion batteries have attracted significant attention as a next-generation energy storage technology because sodium is more abundant and less expensive than lithium. Among various sodium-ion battery cathode materials, Prussian Blue, an iron-based cathode material, is considered highly promising due to its low production cost and high energy-storage capability. One major challenge is that Prussian Blue inherently contains a substantial amount of crystal water during its synthesis. This water can trigger undesirable side reactions, including electrolyte decomposition, gas evolution, and iron dissolution, ultimately reducing battery performance and lifespan. To address this issue, high-temperature heat treatment has been widely used to remove the water. However, battery performance often deteriorates after dehydration, and the underlying cause has remained unclear. The research team focused on the fact that battery performance did not improve as expected even after crystal water had been removed through high-temperature heat treatment. Through detailed analyses of the surface chemical state before and after dehydration, they discovered for the first time that the primary cause of performance degradation is not the crystal water itself, but rather iron–oxygen (Fe–O) bonds that form on the surface of Prussian Blue during heat –treatment. These Fe–O bonds promote surface oxidation, accelerate electrolyte decomposition and gas generation, and ultimately undermine battery performance and stability. Based on this finding, the researchers developed a new solution: a liquid-phase bubbling dehydration process that continuously injects nitrogen gas into a non-aqueous solvent. As nitrogen bubbles pass through the solution, crystal water is effectively removed while minimizing exposure to oxygen, suppressing surface oxidation. The process is analogous to drying wet clothes with a gentle breeze rather than with excessive heat that can damage the fabric. Using this approach, the team reduced the crystal water content of Prussian Blue from approximately 12 wt.% to around 1 wt.% while significantly suppressing surface oxidation. The treated material also generated less gas during battery operation and exhibited superior capacity retention after 100 charge-discharge cycles compared with conventionally heat-treated samples. Importantly, the new process can directly utilize the solvent already employed during electrode fabrication, allowing dehydration and electrode fabrication to be integrated into a single step. This integration minimizes moisture reabsorption, a common issue in conventional processing, and further improves long-term stability. “This liquid-phase bubbling dehydration process integrates dehydration and electrode fabrication into a single operation while preventing moisture reabsorption,” said Professor Changshin Jo. “We believe this process can contribute to the commercialization of next-generation sodium-ion batteries.” The study was supported by the Ministry of Trade, Industry and Energy through the Advanced Specialized Graduate School Program for Batteries, the Energy Technology Development Program, and the Industrial Technology Innovation Program. ▶️ DOI: https://doi.org/10.1002/adma.73507

“No Need for Repeat Shots” — “Just Once Is Enough” A Mussel-Inspired Vaccine Aims to Close the Immunization Gap

[POSTECH and Incheon National University develop mussel adhesive protein to achieve “sustained immunity,” offering a technology that could ease the burden of repeat vaccination] A research team in Korea has developed a vaccine technology that delivers long-lasting immune protection from a single dose by applying the powerful underwater adhesion mechanism of mussels. The work is drawing attention not only for reducing the burden of repeat vaccination, but also for its potential to reach people in countries where vaccine access is difficult. The study was carried out by the team of Professor Hyung Joon Cha of the Department of Chemical Engineering and the School of Convergence Science and Technology at POSTECH, doctoral candidate Sukwon Jung of the Division of Interdisciplinary Bioscience & Bioengineering and doctoral candidate Hyun Tack Woo of the Department of Chemical Engineering, in collaboration with the team of Professor Byeong Hee Hwang of the Division of Bioengineering, Incheon National University. It was recently published in the online edition of Biomaterials, an international journal in the field of biomaterials. Vaccines against infectious diseases such as influenza and COVID-19 are not finished with a single shot. To achieve sufficient immune protection, several booster doses must be administered at set intervals. This translates into a burden of time and cost, and in many countries with insufficient medical infrastructure, vaccination itself is often difficult to carry out. Why are repeat doses needed? Most current vaccines use only a portion of the viral components, which makes them safe but less effective at eliciting an immune response. In addition, vaccine components disappear quickly inside the body, limiting the body’s ability to sustain an adequate immune response. To solve this, the team turned its attention to the mussel, which clings firmly to rocks even against rough waves. By combining the adhesive properties of mussel with a special peptide that strengthens immune function, the team succeeded in creating an “adhesive adjuvant protein (AAP)” capable of anchoring vaccine components at a specific location inside the body. Simply put, they created a “glue for vaccines.” This adhesive adjuvant protein assembles with the antigen, the core component of the vaccine, into nanoparticles and slowly releases both the antigen and the immune-boosting adjuvant itself. Just as a natural infection continuously trains the immune system, the protein stimulates immune cells over a long period to induce a strong and sustained immune response. As a result, the vaccine components remained in the body longer than with conventional aluminum-based adjuvants, and a single dose was confirmed to produce an immune effect lasting more than three times as long than the conventional approach. This protein was designed by combining the original mussel adhesive protein with an adjuvant peptide called “PADRE1)” to enhance the immune response. PADRE is a universal immune-enhancing substance that works broadly regardless of an individual’s immune type; thus, its effect is not limited to specific individuals. By activating a key immune-response pathway (MHC Class II), the team confirmed a balanced increase in the numbers of helper T cells, which assist antibody production. Interestingly, the activity of cytotoxic T cells, which directly attack viruses and even cancer cells, was also significantly elevated. The immune response was maintained even six weeks after vaccination, contributing to the formation of distinct memory T cellsthat support long-term immune memory. Notably, the team confirmed that a healthy immune state was sustained over a long period without “immune exhaustion”, the phenomenon in which immune cells become exhausted and lose their function. If a single dose can produce sufficient immune protection, this technology could become a practical answer for many people. The team plans to develop it into a vaccine for intractable cancers, such as “cold tumors2)” for which immunotherapy has shown limited efficacy. Professor Hyung Joon Cha said, “A functional mussel adhesive protein–based vaccine delivery system has excellent biocompatibility and can be mass-produced, making its potential for practical application is very high,” adding, “We expect it to reduce the burden of repeat vaccination and to contribute to solving global disparities in vaccine access.” This research was supported by the National Research Foundation of Korea’s Global Research Network program and the National Research Laboratory (NRL) 2.0 program. ▶️ DOI: https://doi.org/10.1016/j.biomaterials.2026.124253 1. PADRE : Short for “Pan HLA-DR binding Epitope,” meaning an epitope capable of binding to a universal HLA-DR. It is an artificially synthesized immune-enhancing peptide designed to act broadly across most people, regardless of the differing immune types of individuals. 2. Cold tumor : A tumor in which immune cells (T cells) cannot penetrate into the tumor interior, or in which the immunosuppressive environment surrounding the cancer cells results in a low response rate to immune checkpoint–based cancer therapies.

Cuts cost of building reconstituted cell-free systems by 95%

[Proteins are at the heart of modern biotechnology, driving innovations across various fields. However, the scalable production of large numbers of protein candidates remains a major bottleneck for synthetic biologists.] A research team led by Professor Joongoo Lee in the Department of Chemical Engineering at POSTECH has developed an automated, modular method for assembling reconstituted cell-free systems, which are test-tube systems that can produce proteins outside living cells. The findings were published online on June 6, 2026, in Trends in Biotechnology (Impact Factor: 16.6), an international journal in the fields of biotechnology and synthetic biology. Compared with commercially available kits, this platform reduced preparation costs by 95%, improved cell-free protein synthesis performance by 5-fold, and cut preparation time from 4 days to 2 days. A simple way to understand cell-free protein synthesis is to think of a 3-in-1 instant coffee. Coffee, sugar, and creamer are already mixed in a fixed ratio. All we need to do is add hot water. Cell-free protein synthesis works on a similar principle. Instead of relying on living cells, the translational machinery is prepared in advance, and researchers simply add the DNA, which is the recipe for the protein they want to produce. The problem is that this instant coffee for protein synthesis has been extremely expensive. Only a small number of suppliers provide ready-to-use systems, and preparing them in the lab has involved labor-intensive and time-consuming processes that highly depend on the skill of the experimenter. To overcome this challenge, the POSTECH research team shifted the production of key components outside living cells. Using an E. coli lysate-based cell-free protein synthesis platform, the researchers produced the translation factors directly from the test tubes and integrated the process with an automated liquid handling system. This reduced hands-on time, streamlined the workflow, and made the system more reproducible from batch to batch. Another key advantage of the system is its modular design. Researchers can add or remove individual components depending on their experiments. Using this flexibility, the POSTECH research team successfully incorporated non-canonical amino acids into peptides and proteins. This capability could be useful for biologically engineering high-value therapeutics, including antibody-drug conjugates, in which drug payloads are linked to antibodies. This advance is especially relevant to biofoundries, which are automated infrastructures that use robotics, and artificial intelligence to design, build, test and learn from large numbers of experiments. A lower-cost, customizable, cell-free system could help overcome one of the practical bottlenecks in drug discovery and enzyme engineering. Professor Joongoo Lee of POSTECH, who led the study, explained the significance of the work: "We have built an automated platform that makes cell-free protein synthesis dramatically faster and cheaper, while allowing its components to be freely customized depending on the application." This research was supported by the Bio and Medical Technology Development Program of the National Research Foundation , funded by the Korean government. This research was also supported by a grant from the Korea–US Collaborative Research Fund , funded by the Ministry of Science and ICT and the Ministry of Health and Welfare. This research also supported by the Korea Health Technology R&D Project through the Korea Health Industry Development Institute , funded by the Ministry of Health & Welfare, Republic of Korea. This work made use of the Green Bio Foundry facility at Pohang Technopark, established with funding from the Ministry of Agriculture, Food and Rural Affairs of Korea, Gyeongsangbuk-do Province, and Pohang City. ▶️ DOI: https://doi.org/10.1016/j.tibtech.2026.05.002

Nanoparticle Exsolution Opens a New Route to Functional Oxide Electronics and Spintronics

[Researchers demonstrate a giant insulator-to-metal transition and room-temperature superparamagnetism by controlling defect reconstruction and nickel nanoparticle formation in perovskite oxide thin films] A research team led by Professor Hyeon Han and Professor Donghwa Lee from the Department of Materials Science and Engineering at Pohang University of Science and Technology, together with Professor Sang Ho Oh’s group at Korea Institute of Energy Technology, has developed a new strategy to simultaneously control the electronic and magnetic properties of oxide thin films through a process known as exsolution. Exsolution is a process in which metal ions embedded within an oxide crystal migrate to the surface under reducing conditions and precipitate as metallic nanoparticles. Because these nanoparticles are partially anchored in the oxide lattice, they are more thermally and chemically stable than those deposited by conventional methods. For this reason, exsolution has attracted significant attention in energy-related applications such as catalysis, fuel cells, and electrolysis. However, how exsolution affects the intrinsic electronic and magnetic properties of oxide materials has remained insufficiently understood. To address this question, the research team focused on La0.2Sr0.7Ni0.1Ti0.9O₃-δ, a well-known A-site-deficient perovskite titanate composition known to promote B-site cation exsolution into metallic nanoparticles. By combining comprehensive experimental characterization with density functional theory calculations, the team revealed that this material contains multiple types of defects, including strontium vacancies, oxygen vacancies, lanthanum substitution, and nickel substitution. In the pristine state, these defects electrically compensate one another, resulting in charge-compensated insulating state. After exsolution, however, nickel nanoparticles form both within and on the surface of the flim, and the resulting defect reconstruction in the oxide lattice drives a marked change in the electronic structure. The lattice evolves toward a La-doped SrTiO3-like phase, resulting in a heavily electron-doped, degenerate metallic state. This transformation leads to a giant insulator-to-metal transition with a resistivity change exceeding three orders of magnitude. These results show that exsolution is not merely a method for generating metal nanoparticles; it can also fundamentally modify the electronic structure of the host oxide lattice. The team also observed a striking change in magnetic properties. While the pristine film exhibited nearly diamagnetic behavior, the exsolved film showed room-temperature superparamagnetism, arising from interactions among the newly formed Ni nanoparticles. This demonstrates that exsolution can simultaneously tune both the electrical behavior of the perovskite oxide matrix and the magnetic response of embedded metallic nanoparticles. “This study shows that exsolution can go beyond nanoparticle formation and act as a versatile route to simultaneously control electronic and magnetic properties in oxide thin films,” said Professor Hyeon Han of POSTECH, who led the study. “By combining defect engineering with nanoparticle formation, this approach could open new design strategies for functional electronic and spintronic devices.” This work was supported by the National Research Foundation of Korea funded by the Korean government, the POSTECH International Joint Research Project, the Max Planck Partner Group Programme, the Max Planck-Korea-PSI Center for Quantum Emergent Spintronics (KOMQUEST), and Samsung Electronics Co., Ltd. ▶️ DOI: https://doi.org/10.1002/adma.202600031