3D Printed Brain Sheds Light on Neurological Disorders

A research team led by Professor Dong-Woo Cho (Department of Mechanical Engineering, POSTECH) and Professor Jinah Jang (Departments of Mechanical Engineering, IT Convergence Engineering, Life Sciences, and Interdisciplinary Graduate Program), in collaboration with Dr. Mihyeon Bae, and Dr. Joeng Ju Kim, has successfully developed a three-dimensional (3D) brain model that closely mimics the structure and function of the human brain. The study was published in the International Journal of Extreme Manufacturing, a leading journal in the field of manufacturing and materials science.

Neurodegenerative diseases such as Alzheimer’s and Parkinson’s are notoriously difficult to reverse once they onset occurs, making early diagnosis and predictive modeling critically important. However, the brain is the most complex organ in the human body, with intricately interconnected cells and signaling mechanisms that remain largely unexplored.

Recent studies have suggested that even everyday alcohol consumption may be linked to neural damage, further emphasizing the urgent need for in vitro brain models that can precisely replicate human brain responses in laboratory settings. Existing two-dimensional cell cultures and stem cell-derived organoids have shown significant limitations in reproducing the complex architecture and function of the brain.

To overcome these limitations, the POSTECH research team developed the Bioengineered Neural Network (BENN)—a novel 3D artificial brain model constructed layer by layer, akin to building a house using a 3D printer. A central innovation of this model lies in the biomimetic compartmentalization into two distinct regions: gray matter, which contains neuronal cell bodies, and white matter, which consists of aligned axons that act as information highways facilitating signal transmission.

The researchers applied electrical stimulation to guide the axonal growth of neurons in a specific direction, promoting the formation of aligned and interconnected neural pathways. This led to the establishment of a functional neural network that closely resembles the brain's native signal transmission architecture. Real-time monitoring of calcium ion flux confirmed that the BENN model exhibited electrophysiological responses analogous to those observed in actual brain tissue.

Furthermore, the team utilized the BENN platform to investigate the effects of alcohol exposure on brain function. The model was treated daily with ethanol at a concentration of 0.03%—representative of moderate social drinking—for three weeks. In the gray matter region, they observed elevated levels of Alzheimer’s-related proteins, including amyloid-beta and tau. In the white matter, they identified significant morphological changes in neural fibers, including swelling and distortion. The propagation of neural signals also exhibited marked attenuation. This study is the first to directly visualize and quantify region-specific neurotoxic responses to alcohol in real time using a bioengineered brain model.

Professor Dong-Woo Cho stated, “This model enables high-resolution analysis of neural connectivity and electrophysiological responses that were previously difficult to observe. It holds significant potential for early disease detection and accurate prediction of therapeutic outcomes at the preclinical stage.” Professor Jinah Jang added, “This research marks an important step forward in our ability to investigate the early pathological events of brain diseases in a laboratory setting.”

This research was supported by Korean Fund for Regenerative Medicine funded by Ministry of Science and ICT, and Ministry of Health and Welfare (22A0106L1, Republic of Korea) and the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. 2022M3C1A3081359).

DOI: https://doi.org/10.1088/2631-7990/add632

Drive an electric motor without metal! KIST develops CNT-based ultra-lightweight coil technology

 Using CNTs to develop lightweight electric motors without copper coils

 Potential applications in mobility, energy, robotics, and space

 Whether it's electric vehicles, drones, or spacecraft, a common technical challenge for future transportation is lightweighting. Reducing the weight of a vehicle not only reduces energy consumption, but also increases battery efficiency and increases range. This is considered a key technology that is directly linked to sustainability, as it improves the performance of the system as a whole and thus contributes to reducing carbon emissions. 

Electric motors in particular are an essential component of most electric mobility vehicles, and coils account for a large proportion of the total weight of the motor. Until now, metals such as copper have been used as the main material for coils due to their high electrical conductivity, but it has been consistently pointed out that they have various limitations, such as difficulty in securing resources, price volatility, and weight problems due to high density.

 Dr. Dae-Yoon Kim and his team at the Korea Institute of Science and Technology (KIST) Composite Materials Research Institute have succeeded in constructing the coil of an electric motor using only carbon nanotubes (CNTs) without any metals, and realizing it to the point where it can actually run. The team conducted experiments by applying the coil made of CNTs to the motor and found that the revolutions per minute (RPM) of the motor could be stably controlled according to the input voltage. This demonstrates that the basic operation of a motor, which converts electrical energy into mechanical rotational force, can be accomplished without metal.

 CNTs are one-dimensional tube-shaped nanomaterials with carbon atoms arranged in a hexagonal honeycomb structure, which are known to be much lighter than ordinary metals, while at the same time possessing excellent electrical conductivity, mechanical strength, and thermal conductivity. These properties have long attracted attention as a next-generation material, but CNTs have faced a number of barriers to real-world industrial applications. One of the technical obstacles is the residue of catalyst metals used during the manufacturing process. These remain as metallic particles on the surface of CNTs, degrading their electrical properties, which are directly related to motor performance, making it difficult to utilize CNTs in high-performance components.

 The team has developed a new CNT purification process that utilizes the alignment principle of liquid crystals, a "fourth state of matter" known as the intermediate state between liquid and solid. The process naturally resolves strong aggregation during the alignment of CNTs, effectively removing metallic particles that remain on the surface. Most importantly, it is able to selectively remove impurities without damaging the nanostructure of the CNTs, making it distinctly different from existing liquid- and gas-phase-based purification methods. The purified CNTs show a significant improvement in conductivity, which can be brought to a level that can be applied to actual electric motors.

 "By developing a new concept of CNT high-quality technology that has never existed before, we were able to maximize the electrical performance of CNT coils to drive electric motors without metal," said Dr. Dae-Yoon Kim of KIST. "Based on the innovation of CNT materials, we will take the lead in localizing materials such as conductive materials for batteries, pellicles for semiconductors, and cables for robots."

 This research was supported by the Ministry of Science and ICT (Minister Yoo Sang-im) under the Global Young Connect Project (RS-2024-00448639) and Nano Connect Project (RS-2024-00450610) of the National Research Foundation of Korea. The research was published in the latest issue of the international journal Advanced Composites and Hybrid Materials (IF 23.2 JCR field 1.4%).

Precision Cancer Immunotherapy Target for HPV-positive Oropharyngeal Cancer Discovered Insuk Lee

Joint research team from the College of Life Science and Biotechnology and Medical Center 

discovers precision cancer immunotherapy target for human papillomavirus (HPV)-positive oropharyngeal cancer

Single-cell precision genome analyses were performed

A novel mechanism for determining the effectiveness of immunotherapy for HPV-positive oropharyngeal cancer was presented

The study findings demonstrated possibilities for developing precision immunotherapy for patients with oropharyngeal cancer

A joint research team from the College of Life Science and Biotechnology and Medical Center revealed major cellular and molecular factors that affect the response to immunotherapy via single-cell precision genome analyses of cancer and immune cells in the tumor microenvironment of patients with oropharyngeal cancer. The findings were published on June 11 in the ‘Journal for ImmunoTherapy of Cancer’ (IF: 10.9), a prestigious journal in anticancer immunotherapy.

Oropharyngeal cancer is known to have poor prognosis, and tobacco and alcohol consumption have been identified as its major causes. Recently, there has been a steady increase in oropharyngeal cancer caused by human papillomavirus (HPV) infection. HPV-positive patients with oropharyngeal cancer demonstrated relatively better prognosis than HPV-negative patients under general anticancer therapy. However, a recent large-scale clinical trial has confirmed that there is no significant difference between the prognosis of HPV-positive and -negative patients in response to cancer immunotherapy. Understanding the cause of such results remained an urgent task.

To address this problem, the research team compared and analyzed HPV-positive and -negative oropharyngeal cancer tissues at the single-cell level. They discovered that the expression of specific CD161 receptors in cytotoxic T-cells of HPV-positive patients with oropharyngeal cancer counteracts the effect of anticancer immunotherapy. The expression of CD161 receptors inhibits the expression of CD161 ligands in B cells, thereby preventing the formation of tertiary lymphatic structures that are crucial in immune-mediated anticancer mechanisms. This explains why HPV-positive patients with oropharyngeal cancer have a better prognosis than HPV-negative patients in response to general anticancer treatments, but not in response to immunotherapy.

The results of this study confirmed that the expression of specific CD161 receptors on cytotoxic T-cells can be used to predict the effect of cancer immunotherapy in HPV-positive oropharyngeal cancer. Furthermore, future development of technology targeting CD161 receptors is expected to dramatically improve the efficacy of anticancer immunotherapy in HPV-positive patients with oropharyngeal cancer.

Professor Insuk Lee, the corresponding author, explained the significance of this research: “This research provides an important foundation for future development of therapeutic technology by presenting a novel method that can predict the response of patients with oropharyngeal cancer toward immunotherapy and improve its therapeutic effects.”

Professor Yoon Woo Koh remarked, “The results confirmed that the expression of specific CD161 receptors on cytotoxic T-cells can be used to predict the efficacy of immunotherapy against HPV-positive oropharyngeal cancer.” He added, “the development of CD161 receptor-inhibiting technology in the future will dramatically enhance the efficacy of immunotherapy for HPV-positive patients with oropharyngeal cancer.”

This study was led by Professor Insuk Lee and Professor Sang-Jun Ha from the College of Life Science and Biotechnology, Professor Yoon Woo Koh from the Department of Otorhinolaryngology, Professor Hye Ryun Kim from the Division of Medical Oncology, and was supported by the National Research Foundation of Korea Biomedical Technology Development Next-Generation Applied Omics Project and Leading Research Center Support Project. The first authors of the paper are Junha Cha, PhD candidate from the Department of Biotechnology, Professor Da Hee Kim, and researcher Gamin Kim from the Medical Center.

Find out more: 

Title of article: Single-cell analysis reveals cellular and molecular factors counteracting HPV-positive oropharyngeal cancer immunotherapy outcomes

DOI: https://jitc.bmj.com/content/12/6/e008667

Journal: Journal for ImmunoTherapy of Cancer

Contact corresponding author: Prof. Insuk Lee (insuklee@yonsei.ac.kr)

Excellent Effects of Immediate Post-surgery Exercise for Breast Cancer Justin Y. Jeon

Professor Justin Y. Jeon and Professor Seung-il Kim’s teams reveal the excellent effects of immediate post-surgery exercise for breast cancer 

Early exercise immediately after breast cancer surgery can restore upper limb function without side effects

67.9% of the exercise group regained their shoulder strength to the pre-surgery level  within one month after surgery

Professor Justin Y. Jeon’s team from the Department of Sport Industry Studies, in collaboration with Professor Seung-il Kim’s team from Yonsei Cancer Center, has revealed the effect of customized exercise on upper limb function recovery immediately after breast cancer surgery. While various studies have suggested that “exercise is the best medicine,” this is the first time that immediate post-surgery exercise has been proven to be a groundbreaking treatment for restoring upper limb function in breast cancer patients.

Breast cancer has been the leading type of cancer among women in recent years. Surgical intervention is a primary treatment aiming to completely or partially excise tumors. However, despite advancements in medical technology, approximately 20% of patients undergoing breast cancer surgery experience various after-effects. One of the most common physical after-effects is impairment of upper limb function.

Many studies have repeatedly shown that postoperative exercise during the recovery period positively impacts the upper limb function of breast cancer patients. However, clinical settings often lack sufficient information on which exercises patients should perform, when to start them, and how much to do after surgery, due to factors such as timing, intensity, and type of exercise.

Against this backdrop, the research team thoroughly investigated factors such as constraints on exercise and the speed of upper limb function recovery according to different surgical methods for breast cancer patients, over approximately five years starting from 2017. Based on these results, they developed tailored exercise programs suited to the patient’s surgical method and upper limb function, validating their effectiveness.

The findings showed that when an exercise specialist provided customized exercise training during four outpatient visits within a month after surgery, and patients performed exercises at home using booklets and videos, the upper limb function recovered rapidly within one month.

At one month post-surgery, 67.9% of the exercise group had regained shoulder strength to the preoperative level, whereas only 3.6% of the control group had recovered. In addition, at six months, 85.7% of the exercise group had regained their shoulder strength to the preoperative level even without additional interventions. Contrarily, only 17.9% of the control group had regained their shoulder strength to the preoperative level at six months. This indicates that early exercise immediately after breast cancer surgery may be highly effective for upper limb function recovery. Breast cancer patients included in the exercise group were found to engage in more physical activities even six months after surgery, compared to the control group, and they were found to maintain a higher quality of life.

The method of exercise intervention, involving only four training sessions with an exercise specialist and home-based exercises using videos, appears to be highly cost-effective and positively impacts the improvement of quality of life and prevention of recurrence in breast cancer patients.

Professor Jeon stated, “It has been widely accepted that impairment of upper limb function after breast cancer surgery is inevitable, and rehabilitation treatment has been sought only for lymphedema or severe upper limb dysfunction. This study demonstrates the effectiveness of starting exercise from the first day after surgery to restore upper limb function without side effects. It not only holds academic value but is also a crucial study that can be directly applied to patient care.

The research was published in the prestigious international surgical journal “JAMA Surgery (IF 16.681)” on Jun 5 (local time).

Find out more: 

Title of article: Early Implementation of Exercise to Facilitate Recovery After Breast Cancer Surgery: A Randomized Clinical Trial

DOI: https://jamanetwork.com/journals/jamasurgery/article-abstract/2819794

Journal : JAMA Surgery

Contact corresponding author : Prof. Justin Y. Jeon (jjeon@yonsei.ac.kr)

Boosting the Flavor and Aroma of Cultured Meat Jinkee Hong

[Researchers enhance the sensory qualities of cultured meat, aiming to replicate traditional meat's flavor and aroma for a sustainable future]

Scientists have developed a heat sensitive flavor-package that releases a meaty flavor and aroma when cooking cultured meat.

Research published online in Nature Communications in July, 2024

Global meat consumption is steadily increasing, posing significant challenges due to the meat industry's extensive use of natural resources, including agricultural and grazing land, livestock feed, and water. Additionally, the industry is a major contributor to greenhouse gas emissions and environmental pollution. Over the past two decades, concerns have mounted regarding our capacity to sustain the growing demand for meat in the long term. A worldwide reduction in meat consumption is essential to address these issues.

In response to this pressing challenge, researchers have developed a promising solution: cultured or lab-grown meat. Cultured meat is derived from bovine cells grown in a three-dimensional biomaterial scaffold. These cells proliferate within the scaffold, eventually forming a mass of biological tissue that closely resembles conventional meat. Cultured meat has the potential to become a sustainable meat source for future generations, offering a viable alternative to traditional meat production.

Research on cultured meat has concentrated on perfecting cell growth and the appearance of the final product. But would society be more accepting of cultured meat if it smelled and tasted just like traditional meat? To address this question, a team of researchers led by Professor Jinkee Hong from Yonsei University in Seoul, South Korea, focused on enhancing the sensory qualities of cultured meat to satisfy consumers' senses of smell and taste.

They developed switchable flavor compounds that are released in response to heat. Their inspiration came from the Maillard reaction, which is responsible for the flavorful and aromatic qualities of food when cooked. Professor Hong stated, “As chemical engineers, we conducted this research by combining chemical engineering, biotechnology, and food engineering. We believe that our customizable strategy will contribute to the production of high-quality cultured meat that embodies the sensory characteristics of conventional meat.”

The flavor molecules, held in the bio-scaffold by chemical bonds, are released when these bonds become unstable under heat, such as during cooking. In their study, the researchers tested the stability of these flavor compounds during the initial culturing process and later examined their heat-responsive release. The team developed a variety of flavors to cater to diverse consumer preferences.

Professor Hong notes, “We hope this technology to improve the organoleptic properties of laboratory-grown meat will persuade people to be positive about consuming cultured meat, a major step towards sustainable meat production.”

The sensory features of any food significantly contribute to its popularity. Therefore, incorporating the flavor and aroma of traditional meat into cultured meat is likely to sway public preference towards this sustainable option. In conclusion, this research has a profound impact on our future culinary choices and addresses the environmental and ethical concerns associated with the conventional meat industry.

Find out more 

Title of original article: Flavor-Switchable Scaffold for Cultured Meat with Enhanced Aromatic Properties

DOI: 10.1038/s41467-024-49521-5

Journal: Nature Communications

Contact corresponding author: Prof. Jinkee Hong (jkhong.yonsei@gmail.com)

Harnessing the Power of Magnetism to Control Animal Behavior Jinwoo Cheon, Minsuk Kwak, Jae-Hyun Lee

[External rotating magnetic field triggers the artificial magnetoreceptors, expressed in target neurons within the brain, resulting in neuronal activation that allows the study of consequent changes in behavior.]

Researchers expressed artificial magnetoreceptors in mice that respond to an external magnetic field allowing the study of neuronal activity that controls behavior.

Research published online in Nature Nanotechnology in July, 2024

The allure of controlling brain activity in order to modify human behavior continues to fascinate scientists. Such investigations of neuronal connectivity and function require technologies that can modulate neurons.

Recently, researchers have developed methods to genetically modify specific neurons so they respond to light or chemicals, enabling controlled stimulation and mapping of their functions. However, these techniques are often imprecise and involve invasive procedures with wired or electrode-based tools, making them cumbersome and complex. There is a growing need for less invasive methods that allow for precise control of neurons in live animals.

One promising approach is magnetic field-based neuronal activation, which offers a non-invasive and wireless way to stimulate deep brain regions. However, to achieve precise control using magnetic fields, it's necessary to use magnetic sensors that are specifically targeted to the desired neurons.

To address this challenge, a team of researchers, including Professor Jinwoo Cheon, Director of Institute for Basic Science (IBS) Center for Nanomedicine, Assistant Professors Minsuk Kwak and Jae-Hyun Lee from the Department of Nano Biomedical Engineering (NanoBME) at the Advanced Science Institute, Yonsei University, Korea, developed a Magneto-mechanical Genetics (MMG) technology. This innovative approach harnesses magnetic fields to remotely activate specific neuronal cells in deep brain tissue using targeted nanoparticles.

Highlighting their approach, senior author Prof. Cheon said on behalf of the authors, “We successfully designed and expressed artificial magnetoreceptors in mammalian brains that enables the target animal to sense the applied magnetic fields for modulating brain functions, as intended. This technology has huge potential to unveil novel neural circuitry and to control its functions.”

The team used the Cre-loxP technique to genetically express a modified mechanosensitive ion channel, Piezo1, in specific neuronal cells within the mouse brain. They labeled Piezo1 with a nanomagnetic particle called m-Torquer, which can generate rotating forces or torque in response to an external rotating magnetic field. When exposed to a rotational magnetic force generator, m-Torquer displaces, opening Piezo1 in the target neurons, leading to calcium entry and subsequent neuronal excitation.

MMG stimulation of different neurons in the mouse brain resulted in bidirectional regulation of behaviors such as feeding, sociability, and pup retrieval. These findings suggest the potential application of MMG in regulating dietary habits and social behavior. Unlike prior approaches, MMG's potential scalability to larger animal models is likely to enhance its popularity for future behavioral studies. Further research is needed to determine whether long-term overexpression of Piezo1 or frequent exposure to magnetic stimulation causes any neurotoxicity.

Overall, MMG stimulation appears to trigger quickly reversible changes in neural activity of target cell populations, leading to significant changes in behavior without adverse effects. This study demonstrates the potential of magnetogenetics as an effective research tool for neuronal activity, especially in live animals. 

“We hope that the underlying neural circuits of various neurodegenerative diseases, such as Parkinson’s diseases, Alzheimer’s, and depression, can be revealed to mitigate their symptom and well-being of patients,” concludes Prof. Cheon.

[Find out more]

Title of original article: In vivo magnetogenetics for cell-type-specific targeting and modulation of brain circuits

DOI: https://doi.org/10.1038/s41565-024-01694-2 

Journal: Nature Nanotechnology

Contact corresponding authors: Professor Jinwoo Cheon (jcheon@yonsei.ac.kr), Minsuk Kwak (minsuk.kwak@yonsei.ac.kr), Jae-Hyun Lee (jhyun_lee@yonsei.ac.kr)

Seoul to Invest $23M for First Round of Seoul Vision 2030 Fund This Year, Including AX

The Seoul Metropolitan Government (SMG) recently saw the successful listing of automotive cybersecurity provider Autocrypt—one of its fund-backed startup successes—on the KOSDAQ stock market. To help outstanding startups navigate the "death valley" phase, establish market footing, and scale operations, Seoul is once again boosting efforts through the Seoul Vision 2030 Fund.

The Seoul Vision 2030 Fund is a city-led initiative aimed at nurturing future industries and strengthening the startup ecosystem. From 2023 to 2026, the fund seeks to raise a total of $3.85 billion (₩5 trillion) through city investments, national funds of funds, and private capital. So far, $116 million (₩151 billion) has been committed for 2023–2024, forming a cumulative total of $2.05 billion (₩2.6646 trillion).

📊 Fund Status by Year

Category                        Total            2023      2024

Total Funds               $2.05B     $1.06B     $985M

Seoul Investments         $116M     $54M     $62M

Between July and August, Seoul plans to invest $23 million (₩30 billion) to help reach a fund size of $373 million (₩485 billion) this year. Over half of this will go toward the AI sector, enhancing the city’s competitiveness in AI technologies. The city has previously announced a dedicated AI fund goal of $385 million (₩500 billion) over two years starting in 2025.

Now in its third year, the first round of 2025 investment will inject $23M into key areas:

🧬 First Round 2025 Investment Plan (in USD)

Category            Total Target     AX (AI)   Biotech    “Angel” Startups

Target Funds         $373M     $192M     $146M     $35M

Seoul's Share         $23M            $11.5M      $7.7M     $3.8M

*AX (AI transformation): Covers AI infrastructure, foundational models, data analytics, computing, and full-stack AI services.

From 2019 to 2022, Seoul invested $470 million (₩611.5 billion) in 262 AI companies through its Future Innovation Growth Fund. In 2023–2024, another $56 million (₩72.8 billion) supported 51 AI companies via the Seoul Vision 2030 Fund. These initiatives are tightly linked with city policy and private investor networks to back high-potential startups.

Proposals from fund managers are accepted from 12 PM, Mon, July 14 to 2 PM, Mon, July 28, only via the city’s exclusive cyberlocker, in line with the “Paperless Seoul” policy.

📍 Visit www.seoul.go.kr or www.sba.seoul.kr for the full official announcement.

Wireless Implant Delivers Chemotherapy Deep into Tumors—Without Side Effects

 Dual-phoretic delivery enables localized chemotherapy without systemic side effects

Researchers from Seoul National University (Prof. Seung-Kyun Kang), the Korea Institute of Science and Technology, KIST (Dr. Hyojin Lee), Kwangwoon University (Prof. Jeonghyun Kim), and Gyeongsang National University (Prof. Seongchan Kim) have developed a wireless implantable drug delivery system that enables anticancer drugs to penetrate deep into solid tumors—without harming surrounding healthy tissue. The multidisciplinary team, led by experts in materials science, bioelectronics, and pharmaceutical engineering, offers a new strategy to enhance the efficacy of chemotherapy while minimizing side effects.

Solid tumors, due to their dense cellular architecture and elevated interstitial pressure, have long resisted conventional drug therapies. Anticancer drugs delivered via injection often remain trapped in the outer regions of a tumor, requiring high systemic doses to achieve therapeutic effect. This approach increases the risk of severe side effects such as immune suppression, gastrointestinal toxicity, and the rapid emergence of drug resistance.

▲ (From left) Dr. Sung-Geun Choi, Biomaterials Research Center, Korea Institute of Science and Technology (formerly PhD student at SNU Materials Science and Engineering); Professor Seongchan Kim, College of Pharmacy, Gyeongsang National University; Professor Jeonghyun Kim, Department of Electronic Convergence Engineering, Kwangwoon University; Principal Researcher Hyojin Lee, Biomaterials Research Center, KIST; Professor Seung-Kyun Kang, SNU Department of Materials Science and Engineering

To solve this challenge, the research team developed the Dual-Phoretic Wireless Drug Delivery System (DPw-DDS)—a fully implantable device that uses two ionic transport mechanisms. First, electrophoresis enables on-demand, pulsatile, and quantitative release of drugs using an ion-selective diode. Second, iontophoresis employs electric fields to push those drugs deep into tumor tissue.

Importantly, the system is wirelessly powered using Near-Field Communication (NFC), allowing fully untethered operation without the need for external wiring or batteries. All essential drug delivery steps—storage, release, penetration, and dosing—are integrated into a single, compact device designed for subcutaneous implantation.

In vivo experiments demonstrated that the system achieved over four times greater drug delivery efficiency than standard injection methods and reduced tumor volume by more than 50% within five weeks. Throughout the study, no damage to major organs or surrounding healthy tissue was observed, highlighting the system’s biocompatibility and safety.

Because the system does not require reformulating drugs, it can be readily applied to existing therapeutics, potentially reducing the cost and time associated with drug development. The platform also supports a wide range of drug types—including nanomedicines, protein therapeutics, and mRNA—making it suitable for treating cancer, chronic inflammation, and other precision medicine targets.

Looking ahead, the team aims to extend the platform to biodegradable, non-retrievable implants, eliminating the need for surgical removal and paving the way for long-term, low-burden treatment options. The integration of physical drug delivery principles with wireless bioelectronics marks a major step toward next-generation implantable therapies.

“This system integrates controlled release and deep tissue targeting in a compact wireless form. It could reshape how we treat not only cancer but a wide range of diseases requiring precise and sustained drug delivery,” said Prof. Seung-Kyun Kang (Seoul National University).

“This platform provides a practical solution for improving therapeutic efficacy while minimizing side effects. We are actively working toward clinical translation and commercialization,” added Dr. Hyojin Lee (Korea Institute of Science and Technology).

Fig. 1. Wireless Implantable Dual-Phoretic Drug Delvery System

Fig. 2. Electrophoretic Drug Delvery Control via Electric Field Modulation Using and Ion Diode

Fig. 3. Implantation of Dual_Phoretic System Enhances Drug Penetration and Therapeutic Efficacy

[Reference Materials]

- Title/Journal : “Dual-phoretic wireless device for directionally oriented and carrier-free targeted drug delivery”, Science Advances

- DOI : https://www.science.org/doi/10.1126/sciadv.ads9269

[Contact Information]

Professor Seung-Kyun Kang, Department of Materials Science and Engineering, Seoul National University / +82-2-880-5756 / kskg7227@snu.ac.kr

Disappearing Electronics: Biodegradable Fiber Electronics Could Solve the Growing E-Waste and Textile Crisis

Every time we toss out an old T-shirt or discard a disposable medical patch, we’re contributing to a rapidly escalating environmental crisis. The world produces over 92 million tons of textile waste annually, much of it made from synthetic materials that can linger for centuries. Add to that the surge in wearable electronics — smartwatches, fitness trackers, sensor-laden garments — and the problem becomes twofold. These e-textiles don’t just include fabric, but also metal wires, plastic substrates, adhesives, and circuits that are nearly impossible to recycle. As electronics become more intimate, wearable, and disposable, the question becomes urgent: how do we design them to disappear when they’re no longer needed?

A research team at Seoul National University has taken a significant step toward answering that question. Led by Professor Seung-Kyun Kang and Dr. Jae-Young Bae, the team has developed a fully biodegradable, high-performance conductive fiber that can be seamlessly integrated into wearable electronics — and naturally decompose after use. Unlike conventional e-textiles that persist in landfills, this new fiber system maintains performance during use but vanishes in enzyme-rich or soil environments, leaving no harmful residues behind.

▲ (From left) Yong-Wu Kim (Ph.D.–Integrated Program Student); Dr. Kyung-Sub Kim; Dr. Jae-Young Bae; Prof. Seung-Kyun Kang, all from the Department of Materials Science and Engineering, Seoul National University

The team’s innovation lies in combining tungsten microparticles with a biodegradable polymer known as poly(butylene adipate-co-terephthalate) (PBAT) to form a conductive fiber. This core is coated with a flexible, water-resistant polyanhydride (PBTPA) layer that enhances mechanical stability without compromising biodegradability. The fiber achieves an impressive electrical conductivity of approximately 2,500 S/m, stretches up to 38% without failure, and endures over 20 laundry cycles and 5,000 bending events — performance metrics comparable to or better than many existing e-textile solutions.

Crucially, the fiber is compatible with dry-jet wet-spinning, a scalable process that enabled the team to produce lengths exceeding 10 meters in a continuous run. To validate its real-world applicability, the fiber was integrated into a wearable smart sleeve featuring a temperature sensor, electromyography (EMG) electrodes, and a wireless power coil. The device operated reliably under dynamic movement and environmental stress. After use, the entire system — including the embroidered eco-emblem — began to decompose when exposed to soil or enzymes, fully disintegrating within a few months.

“This is more than just a new material — it’s a platform for sustainable electronics,” said Professor Kang. “We’ve shown that you can have high-functioning wearable devices that don’t become e-waste after their useful life ends.”

Dr. Bae added, “The ability to design electronics that match the lifecycle of the application — and then gracefully disappear — opens up new possibilities in medical patches, smart uniforms, environmental sensors, and beyond. We’re especially excited about the potential for use in disposable healthcare systems that don’t contribute to long-term pollution.”

The research represents a rare confluence of biodegradability, mechanical performance, and mass-manufacturability. Looking ahead, the team aims to expand the platform to incorporate fiber-based memory and logic components, moving toward fully integrated, transient electronic systems. They are also exploring “triggerable” degradation mechanisms that respond to light, heat, or pH — enabling programmable lifespans for future devices.

The study was published in npj Flexible Electronics.

Fig. 1. Mass-Produced Biodegradable Fiber Electrodes

Fig. 2. Biodegradable Fiber-Based Electronic Arm Sleeve

Fig. 3. Degradation of Biodegradable Fiber-Based Eco-Emblem

[Refence Materials]

- Resources : Kim, YW., Kim, KS., Park, JH. et al. Fully biodegradable and mass-producible conductive fiber based on tungsten–poly(butylene adipate-co-terephthalate) composite. npj Flex Electron 9, 62 (2025).

- Video Demonstration : https://youtu.be/lwBe_4SVCF0?si=DzMqQl_YglKY8dIa

- Broadcast Video (YTN Science) : https://www.youtube.com/watch?v=DwbUwIWpfq4

- DOI : https://doi.org/10.1038/s41528-025-00448-x

[Contact Information]

Prof. Seung-Kyun Kang (kskg7227@snu.ac.kr) / Dr. Jae-Young Bae (jy.bae@snu.ac.kr)

SNU-KIST Joint Team Sets New World Record in Thin-Film Tandem Solar Cell Efficiency

Officially Listed on NREL Chart — Korea Expected to Lead Next-Generation Photovoltaic Technology

A team of South Korean researchers has set a new world record in power conversion efficiency* for perovskite/CIGS (copper indium gallium selenide) tandem solar cells**, demonstrating the country’s technological leadership in next-generation photovoltaic (PV) systems.

* Power conversion efficiency: The rate at which a solar cell converts sunlight into electricity.        ** Perovskite/CIGS tandem solar cell: A two-layer thin-film solar cell combining two different types of solar cells that absorb different wavelength ranges of slight energy. This configuration can generate more electricity than conventional single-junction cells, making it a strong candidate for next-generation PV technology.

According to the National Research Foundation of Korea (NRF), the research team led by Professor Jin Young Kim at Seoul National University’s Department of Materials Science and Engineering, and the team led by Dr. Jeung Hyeon Jeong at the Advanced Photovoltaics Research Center of Korea Institute of Science and Technology (KIST), developed a technology that minimizes energy loss in perovskite/CIGS tandem solar cells—setting a new world record with a power conversion efficiency of 26.3%.

▲ (From left) Professor Jin Young Kim, Department of Materials Science and Engineering, Seoul National University; So Jeong Park, Researcher, Department of Materials Science and Engineering, SNU; Dr. Jeung Hyeon Jeong, Korea Institute of Science and Technology (KIST); Eun Pyung Choi, Researcher, KIST

Solar power is essential for achieving the carbon neutrality goal by 2050. However, Korea faces limitations due to its high population density and limited land area, making it difficult to secure large-scale sites for solar farms. In this context, thin-film perovskite/CIGS tandem solar cells offer a highly promising alternative. Their lightweight and flexible nature allows them to be applied like stickers to a variety of surfaces—including building exteriors, windows, car roofs, and soundproof walls—thus maximizing land use efficiency.

The joint research team combined the low-cost, easy-to-fabricate perovskite solar cell with a CIGS cell that can absorb a broader range of the solar spectrum. The result achieved high efficiency in thin-film integration, comparable to that of silicon-based tandem solar cells.

SNU’s team developed advanced materials and fabrication processes to reliably stack perovskite top cells onto the rough surface of CIGS bottom cells. This innovation ensured effective contact between the two solar cells, maximizing photovoltaic performance. KIST’s team optimized the interconnecting layer that bridges the two solar cells to minimize energy loss, enabling the solar cells to achieve maximum power output.

This joint effort led to a record-breaking power conversion efficiency of 26.3%, surpassing the previous record of 24.6% held by a German research institute—an increase of 1.7%. The achievement was officially listed in April 2025 on the certified Best-Research-Cell Efficiency Chart maintained by the U.S. National Renewable Energy Laboratory (NREL).

Commenting on the significance of the achievement, Dr. Jeung Hyeon Jeong stated, “This achievement not only reached the state-of-the-art efficiency but also demonstrated the potential of thin-film tandem technology, which can be applied to various fields such as buildings, automobiles, and aerospace—where conventional silicon-based high-efficiency technologies have inherent limitations.”

Professor Jin Young Kim added, “Being listed on the NREL chart is a major milestone that places Korea at the forefront of perovskite/CIGS tandem solar cell technology. We believe this breakthrough will accelerate development in a field that has seen relatively slow progress and mark a turning point toward broader commercial adoption.”

The research was supported by South Korea’s Ministry of Science and ICT and the National Research Foundation under the Leap-Forward Carbon Neutral Technology Development Program and the Climate Change Response Technology Development Project.

Figure 1. NREL Solar Cell Efficiency Chart (June 2025)

This chart, maintained by the U.S. National Renewable Energy Laboratory (NREL) in Golden, Colorado, shows the world record efficiencies for different types of solar cells. The efficiency of 26.3% achieved by Seoul National University and KIST for perovskite/CIGS tandem solar cells was added in June 2025.

(Source: https://www.nrel.gov/pv/cell-efficiency)

This plot is courtesy of the National Renewable Energy Laboratory, Golden, CO.

Figure 2. Zoomed-in version of the NREL chart (from 2005 onward), highlighting recent records for perovskite/CIGS tandem solar cells. The joint record by SNU and KIST (26.3%) is marked as “SNU/KIST.”

Figure 3. Photograph of the world-record perovskite/CIGS tandem solar cell.

Figure 4. (Left) Schematic diagram of the world-record perovskite/CIGS tandem solar cell. (Right) Cross-sectional image obtained by transmission electron microscopy (TEM).

[Contact Information]

Sojeong Park, Researcher, Department of Materials Science and Engineering, Seoul National University / szpark@snu.ac.kr