Research

Revolutionizing Protein Modification: A New Frontier in Cancer Research

[POSTECH Develops Bio-conjugation Technology for Selective Protein Modification in Live Biological Systems] A research team led by Professor Seung Soo Oh and Dr. Hyesung Jo from the Department of Materials Science and Engineering at POSTECH (Pohang University of Science and Technology) has developed an innovative technique that enables precise modification of specific proteins within complex biological environments. Their pioneering work has been featured as a Supplementary Cover in the Journal of the American Chemical Society (JACS). Proteins are essential components of our bodies and play crucial roles in disease diagnosis and treatment research. Bio-conjugation techniques utilizing proteins, such as attaching fluorescent markers to identify cancer cells, are actively advancing disease diagnosis and drug development research. However, existing methods have significant limitations—they often apply only to a narrow range of proteins, require genetic modifications, or risk damaging protein function due to non-specific modifications. Most challenging of all has been the selective modification of specific proteins in live biological systems. To address these challenges, the research team discovered a novel approach. They developed a technique that combines deoxyoxanosine (dOxa)*1 with aptamers, nucleic acid-based molecular recognition agents, enabling precise modification of desired sites on specific proteins. Using this method, the team successfully attached dOxa to just one of 45 possible reactive sites on a target protein. The dOxa compound proved approximately one million times more stable than conventional biomodification reagents (NHS ester), remaining stable for over a month at room temperature and achieving nearly 100% conjugation efficiency within four hours in biological environments. Notably, the researchers succeeded in bio-orthogonal labeling of two key cancer biomarker proteins—PTK7 and nucleolin—in living cells. This achievement allowed them to observe protein movements in real-time and elucidate the role of these marker protein receptors in cancer cell growth processes. This marks the first successful modification of specific native proteins in biological environments without compromising their functionality. This technology is expected to have applications beyond cancer diagnosis and treatment. It could pave the way for next-generation antibody-drug conjugates (ADCs) targeting specific cancer cells, bioimaging technologies that clearly distinguish cancerous tissues, and personalized precision treatments that maximize therapeutic effects by regulating specific proteins. Additionally, by precisely modifying specific protein sites to regulate enzyme function, it could make significant contributions to drug development and biological function research. Professor Seung Soo Oh highlighted the broad impact of this technology, stating, "This technology will be widely utilized in fields such as protein-based therapeutics, bioimaging, and targeted drug delivery. " Dr. Hyesung Jo, the first author, added, "We've presented an approach that can precisely modify specific proteins as desired. Moving forward, we plan to explore applications in monitoring the unknown mechanisms of living cells and ADC development." This research was supported by the Samsung Research Funding & Incubation Center for Future Technology (SRFC). DOI: https://pubs.acs.org/doi/10.1021/jacs.4c15674 1. dOxa (deoxyoxanosine): A nucleic acid where one N in deoxyguanosine (corresponding to G in DNA sequence) is substituted with O.

POSTECH Unveils World’s First Dynamic Shape-Morphing OLED Panel with Built-In Speaker — All While Maintaining Ultra-Thin

POSTECH Unveils World’s First Dynamic Shape-Morphing Smartphone sized OLED Panel with Built-In Speaker — All While Maintaining Ultra-Thin Flexibility A research team at POSTECH (Pohang University of Science and Technology) has developed the world's first smartphone-type OLED panel that can freely transform its shape while simultaneously functioning as a speaker—all without sacrificing its ultra-thin, flexible properties. This pioneering study, led by Professor Su Seok Choi from the Department of Electrical Engineering and conducted by PhD candidates Jiyoon Park, Junhyuk Shin, Inpyo Hong, Sanghyun Han, and Dr. Seungmin Nam, was published in the March online edition of npj Flexible Electronics, an international journal by Springer Nature. Overcoming Limitations of Current Flexible Displays As the display industry rapidly advances toward flexible technologies—bendable, foldable, rollable, and stretchable—most implementations still rely on mechanical structures such as hinges, sliders, or motorized arms. While these allow for shape adjustment, they also result in increased thickness, added weight, and limited form factor design. These drawbacks are particularly restrictive for smartphones and wearable electronics, where compactness and eleganceare critical. Moreover, for immersive user experiences, current devices often require separate speaker modules, further increasing device complexity and volume. The integration of both shape adaptability and audio functionality has remained a significant challenge—until now. Take bendable displays as a case in point. While they can adjust screen curvature to improve viewing immersion and reduce distortion, most current designs, such as those showcased at MWC 2024, achieve transformation via mechanically forced U-shaped bends. Their flexibility is limited, and they continue to rely on external components for both movement and sound output. POSTECH’s Breakthrough: Shape Transformation and Sound Integration To overcome these limitations, the POSTECH research team introduced a novel solution based on a specialized ultra-thin piezoelectric polymer actuator. When integrated into a flexible OLED panel, this actuator enables electrically driven shape transformation into a wide variety of complex forms—not only concave curves, but also convex, S-shaped, inversed S-Shaped and wave-like configurations that respond dynamically, almost like a display in motion. Crucially, this deformation is achieved entirely through electrical signals, without any mechanical hinges, gears, or external motors. The OLED display maintains its signature thinness, softness, and lightweight profile, achieving new levels of mechanical freedom without any physical burden. Even more impressively, the same actuator can also generate vibrations in response to high-frequency electrical signals, allowing the OLED panel to function as a speaker. This means the display surface itself emits sound, completely removing the need for traditional speaker hardware. “This is the first technology to combine freeform shape morphing and built-in sound output in a single ultra-thin OLED panel, without external components,” said Professor Choi. “We preserved everything OLEDs are known for—thinness, flexibility, and lightweight—and expanded their functionality in a whole new direction of complex and dynamic shape morphing with additonal sound emission.” Demonstrated on Real OLED Panels The research team successfully implemented this technology on an actual smartphone-scale OLED panel. The panel demonstrated reliable, reversible shape transformation between a variety of geometries and clear sound generation—all while remaining compact, flexible, and thin. This first and all-in-one solution contrasts sharply with current commercial displays. For example, LG’s CES 2025 award-winning 5K 2K bendable monitor still relies on motorized structural support, and Samsung’s AI-enhanced OLEDs showcased at MWC 2024, while impressive, do not integrate audio into the display surface itself and wrapping conventional bulky sepeaker with bendable OLED using structural support as well. POSTECH’s approach uniquely merges mechanical adaptability and acoustic output—fully embedded in the OLED structure itself. As a result, all while maintaining ultra-thin flexibility is achieved in compact size of smartphone. Implications for Next-Generation Devices This innovation lays the groundwork for a new generation of intelligent, shape-adaptive, and audio-responsive displays across multiple industries. Potential applications range from morphing mobile displays, immersive automotive dashboards, and audiovisual wearables, to soft robots with interactive, expressive surfaces. The research was supported by Korea’s Ministry of Trade, Industry and Energy (Technology Innovation Program), the LG Display–POSTECH Incubation Collaboration Project, and the National Research Foundation of Korea’s BK21 FOUR program. Key Highlights: • First-ever OLED panelto achieve both shape transformation and sound emission • Fully mechanically-free: no hinges, sliders, or external speakers • Maintains OLED’s ultra-thin, lightweight, and flexible & multi shape transform form factors • Demonstrated on smartphone-scale panels with dynamic, reversible shape control • Opens new pathways for next-generation mobile, automotive, and soft robotic interfaces

Overcoming Stacking Constraints in Hexagonal Boron Nitride via Metal-organic Chemical Vapour Deposition

[POSTECH and University of Montpellier researchers demonstrate wafer-scale AA-stacked hexagonal boron nitride (hBN) growth] Researchers from Pohang University of Science and Technology (POSTECH) and the University of Montpellier have successfully synthesized wafer-scale hexagonal boron nitride (hBN) exhibiting an AA-stacking configuration, a crystal structure previously considered unattainable. This achievement, accomplished via metal-organic chemical vapour deposition (MOCVD) on a gallium nitride (GaN) substrate, introduces a novel route for precise stacking control in van der Waals materials, impacting potential applications in quantum photonics, deep-ultraviolet (DUV) optoelectronics, and next-generation electronic devices. The study, led by Professors Jong Kyu Kim and Si-Young Choi (POSTECH) and Guillaume Cassabois (University of Montpellier), provides key insights into the factors influencing unconventional stacking configurations. Published in Nature Materials, the findings challenge previous assumptions about stacking constraints in hBN, demonstrating that step-edge guided growth and charge incorporation are essential in stabilizing the thermodynamically unfavorable AA stacking configuration. hBN has long been regarded as a key insulating material for 2D electronic, photonic, and quantum applications. Typically, hBN adopts an AA' stacking configuration, in which boron and nitrogen atoms alternate vertically between layers. In contrast, the AA stacking configuration―where identical atoms align vertically―has traditionally been considered unstable due to strong interlayer electrostatic repulsion. Through detailed investigation, the research team discovered that step-edges on vicinal GaN substrates serve as nucleation sites, promoting the unidirectional alignment of hBN layers and minimizing rotational disorder. This step-edge guided growth mechanism enabled the formation of high-quality, wafer-scale AA-stacked hBN films, ensuring both structural uniformity and crystallinity required for practical electronic and photonic applications. Furthermore, the study highlights the critical role of electronic doping through carbon incorporation during the MOCVD process. The presence of carbon, confirmed through structural and spectroscopic analyses at POSTECH and Pohang Accelerator Laboratory (4D and 10D beamlines), introduces excess charge carriers, altering interlayer interactions and effectively mitigating the repulsive forces typically associated with AA stacking. Together, this charge-mediated stabilization and step-edge alignment constitute a previously unexplored mechanism for engineering tailored stacking sequences in van der Waals materials. "Our research demonstrates that stacking configurations in van der Waals materials are not purely governed by thermodynamic considerations, but can instead be stabilized through substrate characteristics and charge incorporation," remarked Professor Jong Kyu Kim who led the study. "This insight significantly expands the potential for customized 2D material architectures with distinct electronic and optical properties.“ Optical characterization of the synthesized AA-stacked hBN revealed enhanced second-harmonic generation (SHG)—a hallmark of non-centrosymmetric crystal structures—indicating promising applications in nonlinear optics. Additionally, the material exhibited sharp band-edge emission in the DUV region, suggesting its potential for high-efficiency optoelectronic devices operating in the DUV spectrum. "Achieving wafer-scale control of stacking order is an important milestone for scalable, high-performance 2D electronic and photonic systems," said Seokho Moon, a postdoctoral researcher in Professor Jong Kyu Kim’s lab and the lead author of the study. "This work highlights the versatility of MOCVD as a platform for precisely engineered van der Waals materials.“ The research was supported by the Global Ph.D. Fellowship Program and the Basic Science Research Capacity Enhancement Program (Materials Imaging & Analysis Research Center) by the Ministry of Education, the Mid-Career Researcher Program and the Nano and Materials Technology Development Program of the Ministry of Science and ICT, the Electronic Components Industry Technology Development Program of the Ministry of Trade, Industry & Energy, and Samsung Electronics. DOI: https://doi.org/10.1038/s41563-025-02173-2 1. h-BN: hexagonal boron nitride

Shaping the Future of Diabetes Treatment with 3D Biorinting Technology

[POSTECH develops an innovative platform that replicates pancreatic functions, transforming diabetes therapy] A research team led by Professor Jinah Jang from the Departments of Mechanical Engineering, Life Sciences, IT Convergence Engineering, and the Graduate School of Convergence Science and Technology at Pohang University of Science and Technology (POSTECH), along with Myungji Kim, an Ph.D. candidate in the Division of interdisciplinary bioscience and bioengineering (i-bio) have successfully developed an innovative platform for diabetes treatment using bioink derived from pancreatic tissue and 3D bioprinting technology. This study was recently published online in Nature Communications. Diabetes is a metabolic disorder caused by dysfunction in the pancreas, the organ responsible for regulating blood sugar levels. Within the pancreas, islet cells secrete insulin to lower blood sugar. However, producing these cells for therapeutic use has proven extremely challenging. While stem cells offer a promising route to generating islets in vitro, recreating the exact microenvironment and vascular niche they need to function—similar to that of a real pancreas—has been a major obstacle. Islet cells regulate insulin secretion through interactions with surrounding components of the extracellular matrix (ECM)*1 and vascular cells. The POSTECH team developed a specialized bioink called PINE (Peri-islet Niche-like ECM), which includes ECM and basement membrane proteins—such as laminin and collagen IV—partially extracted from actual pancreatic tissue. Leveraging 3D bioprinting technology, the team then fabricated the Human Islet-like Cellular Aggregates and Vasculature (HICA-V) platform. The HICA-V platform precisely arranges stem cell-derived islet cells alongside vascular structures, closely mimicking the architecture of a real endocrine pancreas. Islet cells cultured within the HICA-V platform demonstrated increased insulin production and binding protein expression, exhibiting functional characteristics comparable to native islets. Moreover, the platform successfully replicated pathological responses seen in diabetic conditions, such as elevated expression of inflammatory genes. This not only promotes the maturation of islets but also establishes the platform as a valuable tool for diabetes research and drug development. Professor Jinah Jang, who led the study, stated "The customized pancreatic islet platform developed through this research faithfully replicates the structure and function of the human endocrine pancreas, supporting the maturation and functional enhancement of stem cell-derived islets." She added, "We anticipate this platform will play a key role in advancing diabetes research, accelerating anti-diabetic drug development, and improving the efficiency of islet transplantation therapies.“ This work was supported by the National Research Foundation of South Korea (NRF) grant funded by the Ministry of Science and ICT, Korean Fund for Regenerative Medicine funded by Ministry of Science and ICT, and Ministry of Health and Welfare, and the Alchemist Project funded By the Ministry of Trade, Industry & Energy(MOTIE, Korea). DOI: https://doi.org/10.1038/s41467-025-56665-5 1. Extracellular Matrix (ECM): a complex network of proteins and biomolecules that provides structural and biochemical support to cells, regulating adhesion, migration, differentiation, and tissue organization.

Breakthrough Nano-Spring Technology Boosts Battery Durability and Energy Density

[POSTECH, Samsung SDI, Northwestern University, and Chung-Ang University improved the battery durability and energy density with nano spring coating] A research team led by Professor Kyu-Young Park from the Institute of Ferrous & Eco Materials Technology, Department of Materials Science & Engineering, POSTECH conducted joint research with Samsung SDI, Northwestern University, and Chung-Ang University research team to develop technology that will dramatically increase the lifespan and energy density of electric vehicle (EV) battery. This research was recently published in "ACS Nano" online, an international academic journal of materials. An electric-vehicle battery must maintain its performance while repeatedly being charged and discharged. However, the current technology has one big issue: the charging and discharging process causes the battery's positive active materials to expand and contract repeatedly, causing microscopic cracks within. As the time goes, the battery performance drastically decreases. To prevent this, researchers are increasing strength of the cathode active materials or by adding reinforcement dopant, but these could not become a fundamental solution. The key to this research is the ‘nano-spring coating’ technology that can design elastic structures. The research team im\plemented a multi-walled carbon nanotube (MWCNT) on the surface of battery electrode materials. This absorbed strain energy generated from the charging and discharging process, preventing cracks, and minimizing thickness changes in electrodes to improve stability. The team successfully and effectively suppressed cracks within the battery and simultaneously improving its lifespan and performance. This technology allows you to minimize resistance caused by volume changes of the material with only a small amount (0.5wt%, weight percentage) of conductive material*1 . It can realize a high energy density of 570 Wh/kg*2 or above. Also, it shows excellent lifespan by maintaining 78% of the initial battery capacity after 1,000 charge and discharge cycles or above. In particular, this technology can be easily combined with the existing battery manufacturing processes, allowing easy mass production, and commercialization. This development is expected to overcome current limitations in battery technology, paving the way for more efficient and durable EV batteries. This can contribute to the development of electric vehicles that are superior to the existing ones. Professor Kyu-Young Park of POSTECH said, "With a different approach from existing ones, this research effectively controlled changes that could occur to a battery during the charging and discharging process. This technology can be widely used not only in the secondary battery industry but also in various industries where material durability is important." This research was supported by Samsung SDI, Ministry of Trade, Industry and Energy, and basic research fund from the Ministry of Science and ICT. DOI: https://pubs.acs.org/doi/full/10.1021/acsnano.4c14980# 1. Conductive Material: A highly conductive substance added to the electrode to facilitate electron transfer to the active material. Commonly used conductive materials include carbon-based substances such as Super P, CNT (carbon nanotubes), and graphene. 2. Wh/kg (Watt-hour per kilogram, specific energy density): A unit that represents the amount of energy (Wh) a battery can store per kilogram. This metric is used to indicate the energy density of a battery.

Real Time Monitoring of Stroke Using Light and Sound

[POSTECH successfully observed early vascular changes in stroke using an innovative photoacoustic technique] Every year, millions of people die from stroke. In order to win against this disease which occurs the moment when a blood vessel is blocked in brain, a POSTECH research team made a breakthrough with a cutting-edge technology combining light and sound. Stroke is the second most common cause of death worldwide. In particular, ischemic stroke occurs when a blood vessel supplying blood to your brain is blocked. If treatment is delayed, a patient will have accelerated brain tissue damage; making it virtually impossible to recover. The existing technologies such as CT and MRI have limitations capturing any early vascular changes in real-time. Furthermore, animal model researches have limitations with scope and efficiency. To solve this, the POSTECH research team developed a photoacoustic computed tomography (PACT*1 ) that combines light and ultrasound. The research team applied a complex scanning method that combines linear and rotational scanning to synthesize images from multiple angles into one. It is the same method used to take images from different directions and reconstitute them into a 3D image. Using this technology, the research team was able to non-invasively monitor cerebrovascular changes within small animals with the early stages of an ischemic stroke in real time; successfully analyzed vascular changes in a wide region with precision. In addition, the team developed an algorithm that non-invasively observes hemoglobin and measures oxygen saturation in each blood vessel in real time by utilizing multi-wavelength photoacoustic imaging within a near-infrared region. This allowed the team to precisely monitor not only ischemic lesions but also collateral blood flow and neovascular changes. These results were proven reliable compared to the existing pathological tissue tests, and showed that the new PACT system can effectively track the vascular recovery process after stroke. The POSTECH research team said, "The most significant result from this research is that we can now have precise observation of blood flow changes without using contrast." This will provide new experimental approaches not only for stroke treatment research but also for research on various neurological and vascular diseases." This research was conducted by the following members: - Professor Yong-Joo Ahn from the Department of Convergence IT Engineering, and the School of Convergence Science and Technology - Professor Chul-Hong Kim from the Department of Electrical Engineering, Department of Convergence IT Engineering, Department of Mechanical Engineering, and the Graduate School of Convergence Science and Technology - Ji-Woong Kim from the Department of Convergence IT Engineering integrated course - Joo-Young Kwon from the School of Convergence Science and Technology integrated course - Dr. Seoung-Wook Choi (Ph.D., Stanford University) from POSTECH Institute of Artificial Intelligence - Hyun-Seo Jeon of the Department of Convergence IT Engineering integrated course - Min-Sik Seong of the Department of Mechanical Engineering integrated course - Research team of Chengbo Liu and Rongkang Gao from the Chinese Academy of Sciences This research was recently published in "Advanced Science," one of the international scientific academic journals. This research was hosted by the BK21 FOUR project of the National Research Foundation of Korea, the ICAN program hosted by the Ministry of Science and ICT and the Institute of Information & communications Technology Planning & Evaluation, medical device industry promotion project of the Korea Medical Device Industry Association, health and medical treatment technology R&D project supported by the Korea Health Industry Development Institute with funds from the Ministry of Health and Welfare, Glocal University 30, and financial support from the Hyundai Motor Company Chung Mong-Koo Foundation. DOI: https://doi.org/10.1002/advs.202409361 1. Photoacoustic computed tomography (PACT): an imaging technology that combines light and ultrasound to non-invasively observe the tissue structure and function in real time with high resolution.

Aluminum: a New Hero of Hydrogen Production

[POSTECH and Sogang University developed a method to utilize aluminum to improve performance of water electrolysis catalyst] Aluminum (Al) has been considered as a material susceptible to corrosion, but it will become key to core technology in producing clean hydrogen energy. Recently, a POSTECH research team succeeded in dramatically improving the performance of hydrogen production catalysts using this unstable metal. This research was conducted by the team of: Professor Yong-Tae Kim of the Department of Materials Science and Engineering, and Graduate Institute of Ferrous & Eco Materials Technology at POSTECH; Dr. Sang-Moon Jung of the Department of Materials Science and Engineering, Ph.D. candidate Byeong-Jo Lee, and professor Seoin Back's team of Sogang University. The research was recognized for its excellence and was published as the cover paper of "ACS Catalysis," an academic journal published by the American Chemical Society (ACS). Hydrogen is being spotlighted as a clean energy source replacing fossil fuels, and water electrolysis all of which is used to mass produce hydrogen using water. In particular, researches on alkaline water electrolysis using alkaline solution as an electrolyte are being actively conducted, as it is cost-effective and suitable for mass production. Water electrolysis requires a catalyst that accelerates 2 important reactions. One of them is "hydrogen evolution reaction" (HER), which produces hydrogen gas (H2) by combining hydrogen ions (H+) and electrons. Another one is "oxygen evolution reaction" (OER), which produces oxygen gas (O2) as hydroxyl ions (OH-) lose electrons. However, nickel-iron (Ni-Fe) is a based catalyst mainly used in oxygen production reaction; it has had difficulties in commercializing due to its lack of activity and durability. The research team solved the problem using aluminum. Aluminum is generally known to be easily corroded in alkaline environments, but the research team overcame the problem by designing it to form a stable structure on the surface of an electrode. As a result, aluminum efficiently controlled the existing catalytic electron structure without corrosion, accelerating oxygen production reaction. Experiments conducted in an alkaline water electrolysis cell showed the results that the nickel-iron-aluminum (Ni-Fe-Al) catalyst improved performance by approximately 50% compared to existing catalysts. The research team confirmed that the aluminum catalyst maintained high current density even at low voltage. Additionally it was proven to be applicable in a large-scale hydrogen production process, as it maintained excellent stability in a long-term operation. Professor Yong-Tae Kim, the leader of this research, said, "This research broke the stereotypes of existing catalyst designs. By using this innovative approach of utilizing aluminum, we were able to drastically improve the performance of catalysts used in a hydrogen production system. I expect this research would substantially advance the age of hydrogen economy and become a new milestone of eco-friendly energy technology." This research was supported by the National Research Foundation of Korea, Ministry of Science and ICT, and Ministry of Trade, Industry and Energy. DOI: https://pubs.acs.org/doi/10.1021/acscatal.4c04393?ref=PDF

‘Fluorescent Phoenix’ Discovered with Persistence Rivaling Marie Curie’s

POSTECH Research Team Develops Ultra-Photostable Organic Fluorescent Molecule (PF555) to Unveil the Secrets of Intracellular Proteins A research team at POSTECH (Pohang University of Science and Technology) has successfully developed a super-photostable organic dye after two years of dedicated research—demonstrating perseverance akin to that of Marie Curie, who painstakingly extracted just 0.1 grams of radium from eight tons of ore to earn her Nobel Prize. Single-molecule imaging, a technique that uses fluorescent markers to track proteins with precision, plays a crucial role in cell biology, biochemistry, molecular biology, and drug discovery. However, conventional organic fluorophores have been hindered by their low photostability. The issue of photobleaching—the loss of fluorescence upon prolonged light exposure—has made it difficult to track proteins inside cells or monitor intricate biological processes over extended periods. Professor Sung Ho Ryu’s research team at POSTECH made a serendipitous yet groundbreaking discovery while conducting single-molecule imaging: an ultra-photostable fluorescent molecule that emerged as a result of the photoblueing*1 phenomenon. In collaboration with Professor Young-Tae Chang’s team, they identified its structure using mass spectrometry and nuclear magnetic resonance analysis, naming it Phoenix Fluor 555 (PF555). PF555 offers significantly greater photostability than existing fluorescent dyes, making it highly effective for tracking both individual proteins at the single-molecule level and multiple proteins simultaneously at a bulk level. Notably, PF555 remains unaffected by oxygen concentration and has a long photobleaching lifetime*2 . Using PF555, the research team was able to observe biological processes that were previously untraceable, including endocytosis and protein interactions. Their findings revealed that the Epidermal Growth Factor Receptor (EGFR)—a key regulator of cell growth and differentiation—exists in two distinct states: one in which it remains trapped within Clathrin-Coated Structures (CCS)*3 on the cell membrane, and another where it moves around its surroundings. This suggests that EGFR actively navigates its environment, potentially to detect external signals or facilitate molecular interactions. Thanks to PF555’s unparalleled photostability, researchers were able to track the complete process of EGFR’s endocytosis and recycling, something that had been challenging with conventional fluorescent dyes. Professor Sung Ho Ryu remarked, “PF555 is an ultra-stable organic fluorophore unlike any previously reported. It will allow researchers to observe biological phenomena that were once restricted by time limitations.” Professor Young-Tae Chang added, “The extraordinary stability of PF555 sets a new benchmark for organic fluorophores,” emphasizing its broad applications in drug development, disease diagnostics, and cellular imaging. This research was conducted by Professor Sung Ho Ryu, Dr. Do-Hyeon Kim, and Dr. Hong Minh Triet from POSTECH’s Department of Life Sciences, in collaboration with Professor Young-Tae Chang from the Department of Chemistry and Dr. Sun Hyeok Lee from the Graduate School of Convergence Science and Technology. Their findings were recently published in Nature Methods, a globally recognized journal in biochemical research. This study was supported by the National Research Foundation of Korea, the Institute for Basic Science, and the Glocal University 30. https://doi.org/10.1038/s41592-024-02584-0 1. Photoblueing: It refers to the phenomenon where a fluorescent dye degrades due to light exposure or undergoes structural changes, causing its emission spectrum to shift toward the blue region. 2. Photobleaching lifetime: It refers to the duration until a fluorescent material is irreversibly degraded upon exposure to light. 3. Clathrin-Coated Structures (CCS): It is a membrane structure coated with clathrin proteins, primarily observed during vesicular transport processes within the cell.

Highly Uniform Nanocrystals Synthesized by Liquid Crystalline Antisolvent

[POSTECH Develops Mass Synthesis Technology for Uniform High-Performance Perovskite Nanocrystals Using Liquid Crystals as Antisolvents] A research team led by Professors Young-Ki Kim and Yong-Young Noh at POSTECH has developed a groundbreaking method for synthesizing perovskite nanocrystals (PNCs), a next-generation semiconductor material, in a more uniform and efficient manner. This study is expected to serve as a key breakthrough in overcoming the complexities of conventional synthesis methods and accelerating the commercialization of various optoelectronic devices, such as light-emitting diodes (LEDs) and solar cells, that utilize nanocrystals. This study was conducted by Professor Young-Ki Kim and Professor Yong-Young Noh from the Department of Chemical Engineering at POSTECH, along with Ph.D. candidate Jun-Hyung Im, Dr. Myeonggeun Han (Samsung Electronics), and Dr. Jisoo Hong (Princeton University). The research was recently published in ‘ACS Nano’, an international journal in the field of nanotechnology. PNCs have great potential in next-generation solar cells and high-efficiency displays, as their ability to absorb and emit light can be precisely controlled based on particle size and shape through the ‘quantum confinement effect.’ However, conventional methods used to synthesize PNCs such as ‘hot-injection’ and ‘ligand-assisted reprecipitation (LARP)’ have limitations in producing uniformly sized and shaped particles due to high synthesis temperatures and complex experimental conditions. As a result, additional processing steps were required to obtain particles with the desired properties, which in turn reduced productivity and restricted industrial applications. The POSTECH research team has developed a synthesis method that precisely controls the size and shape of PNCs using a ‘liquid crystal(LC)’ as an antisolvent in the LARP method. LC is an intermediate phase of matter that possesses both liquid-like fluidity and crystal-like long-range molecular ordering. In LC phases, molecules are aligned to a preferred orientation (defined by the director), which leads to elasticity. Therefore, when an external force is applied to an LC medium, LC molecules are reoriented, producing considerable elastic strains. Inspired by this property, the team precisely controlled the growth of PNCs by simply replacing the antisolvent in the conventional LARP method with LC while maintaining the other synthesis conditions. The elastic strains of LCs restricted the growth of PNCs upon reaching the extrapolation length (ξ)*1 of LCs, enabling mass production of uniformly sized PNCs without the need for additional purification processes. The research team also discovered that the interaction between ligands binding to the surface of PNCs and LC molecules plays a crucial role in reducing surface defects. Since LC molecules have a long, rod-like structure, ligands can be densely arranged between them. As a result, ligands bind more densely to the surface during nanocrystals formation, thereby minimizing surface defects and enhancing luminescence properties. Professor Young-Ki Kim explained, “The synthesis method developed by our research team is highly compatible with existing synthesis techniques, such as ligand exchange and microfluidic synthesis, and will enhance the performance of various optoelectronic devices, including LEDs, solar cells, lasers, and photodetectors.” He also stated, “This technology enables the large-scale production of uniform, high-performance nanocrystals at room temperature, and we anticipate it will help accelerate the commercialization of nanocrystal-based optoelectronic devices.” This research was supported by the Basic Research Program (Hanwoomul-Phagi Basic Research) and the Pioneer Program for Promising Future Convergence Technology of the National Research Foundation of Korea (NRF). DOI: https://doi.org/10.1021/acsnano.4c13217 1. Extrapolation length (ξ): A characteristic length of liquid crystal, defined as ξ=K/W, where K is the Frank elastic constant of the liquid crystal and W is the surface anchoring energy density. When an inclusion of size L exceeds ξ (i.e., WL2 > KL), the liquid crystal molecules in the vicinity of the inclusions reorient, resulting in elastic strain.

Personalized Cancer Treatment Using 3D Bioprinting Technology

[POSTECH and The Jackson Laboratory, Developing an In Vitro Platform to Evaluate and Predict Drug Responses in Gastric Cancer Patients] A collaborative research team led by Professor Jinah Jang from the Department of Mechanical Engineering and the Department of Creative IT Engineering at POSTECH (Pohang University of Science and Technology) and Professor Charles Lee from The Jackson Laboratory for Genomic Medicine in the United States has successfully developed a gastric cancer model using 3D bioprinting technology and patient-derived cancer tissue fragments. This innovative model preserves the characteristics of actual patient tissues and is expected to rapidly evaluate and predict individual patient drug responses. The research has been published in the international journal Advanced Science. Tumor heterogeneity poses a significant challenge in the development and treatment of cancer therapies, as patient responses to the same drug varies, and the timing of treatment is a critical factor influencing prognosis. Therefore, technologies that predict the efficacy of anticancer treatments play a vital role in minimizing side effects and enhancing treatment efficiency. Existing approaches, such as gene panel-based tests and patient-derived xenograft (PDX) models, are limited in their applicability to certain patients, have constraints in predicting drug effects, and require substantial time and costs to establish. In this study, the research team developed an in vitro gastric cancer model by leveraging 3D bioprinting technology and tissue-specific bioink incorporating patient-derived tissue fragments. Notably, they encapsulated cancer tissues within a stomach-derived decellularized extracellular matrix (dECM) hydrogel, artificially enabling cell-matrix interactions. By co-culturing these tissues with human gastric fibroblasts, they successfully mimicked cancer cell-stroma interactions, thereby recreating the in vivo tumor microenvironment in vitro. This model demonstrated the ability to preserve the unique characteristics of gastric tissues from individual patients by replicating both cell-stroma and cell-matrix interactions. It exhibited high specificity in predicting the patient’s anticancer drug responses and prognosis. Furthermore, the model’s gene profiles related to cancer development, progression, and drug response closely resembled those of patient tissues, surpassing the performance of conventional PDX models. Additionally, the rapid fabrication method of this model via bioprinting enables drug evaluation within two weeks of tumor tissue extraction from the patient. This efficient platform is anticipated to significantly contribute to the development of personalized cancer treatments. Professor Charles Lee from The Jackson Laboratory for Genomic Medicine, who led the study, expressed his expectations for the model: “By reproducing cancer cell-stroma and cell-matrix interactions, this model enhances the accuracy of drug response predictions and reduces unnecessary drug administration to non-responsive patients.”Professor Jinah Jang of POSTECH emphasized the significance of the research: “This is a critical preclinical platform not only for developing patient-specific treatments but also for validating new anticancer drugs and combination therapies.” This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (No. 2020R1A6A1A03047902) and by the National Research Foundation of Korea (NRF) grants funded by the Korea government (MSIT) (No. 2022M3C1A3081359, No. 2021R1A2C2004981). DOI: https://doi.org/10.1002/advs.202411769