KAIST

<Professor Kyung Cheol Choi, (Upper Left) Dr. Eun Hae Cho>

A new solution that could overcome the limitations of conventional hair-loss treatments is emerging. Heavy and rigid helmet-type phototherapy devices may soon become a thing of the past. A joint research team has developed a hat-like, wearable OLED-based phototherapy device and demonstrated that it can suppress hair-follicle cell aging by up to 92%, a key factor in hair-loss progression.

KAIST (President Kwang Hyung Lee) announced on the 1st of February that a research team led by Professor Kyung Cheol Choi of the School of Electrical Engineering, in collaboration with Professor Yun Chi’s group at the Hong Kong University of Science and Technology, has developed a non-invasive* hair-loss treatment technology using a textile-like, flexible wearable platform integrated with specially designed OLED light sources.
*Non-invasive treatment refers to therapies that do not involve skin incisions or direct physical damage to the body.

Although drug-based treatments for hair loss have been known to be effective, concerns over side effects from long-term use have driven interest in safer alternatives such as phototherapy. However, existing phototherapy devices for hair loss are typically bulky, rigid helmet-type systems, limiting their use to indoor environments. Moreover, because they rely on point light sources such as LEDs or lasers, it has been difficult to deliver uniform light irradiation across the entire scalp.

To address these challenges, the researchers replaced point light sources with area-emitting OLEDs, which emit light uniformly over a wide surface. In particular, they integrated near-infrared (NIR) OLEDs into a soft, fabric-like material that can be worn as a cap. This design allows the light source to naturally conform to the contours of the scalp, delivering even optical stimulation over the entire scalp.

Beyond wearable design, the study focused on suppressing hair-follicle cell aging, a central driver of hair-loss progression. The key achievement of this work lies not only in realizing a wearable device, but also in precisely tailoring the wavelength of light to maximize therapeutic efficacy.

Recognizing that cellular responses vary depending on light wavelength, the team extended wavelength-control techniques originally developed for display OLEDs to therapeutic applications. As a result, they fabricated customized OLEDs that selectively emit near-infrared light in the 730–740 nm range, which is optimal for activating dermal papilla cells—critical cells located at the base of hair follicles that regulate hair growth.

The effectiveness of the developed NIR OLEDs was validated through experiments using human dermal papilla cells (hDPCs). Cellular aging analysis showed that NIR OLED irradiation suppressed cell aging by approximately 92% compared with the control group, outperforming conventional red-light irradiation conditions.

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< Schematic diagram of phototherapy using a textile-based near-infrared OLED cap >

First author Dr. Eun Hae Cho commented, “Instead of rigid, helmet-type point-light devices, we propose a wearable phototherapy platform that can be used in daily life by implementing soft, textile-based OLEDs in a cap form. A key outcome of this study is demonstrating that precisely engineered light wavelengths can effectively suppress hair-follicle cell aging.”

Professor Kyung Cheol Choi added, “Because OLEDs are thin and flexible, they can closely conform to the curved surface of the scalp, delivering uniform light stimulation across the entire area. Going forward, we plan to verify safety and efficacy through preclinical studies and progressively evaluate the potential for real therapeutic applications.”

This research was led by Dr. Eun Hae Cho of the KAIST School of Electrical Engineering as first author and was published online on January 10 in the international journal Nature Communications.
※ Paper title: “Wearable Textile-Based Phototherapy Platform With Customized NIR OLEDs Toward Non-Invasive Hair Loss Treatment", DOI: https://doi.org/10.1038/s41467-025-68258-3, Co-authors: Eun Hae Cho, Jingi An, Yun Chi, Kyung Cheol Choi

< Prototype of a textile-based near-infrared OLED and its phototherapeutic efficacy >

This research was conducted with the support of the Ministry of Science and ICT through the National Research Foundation of Korea (NRF) under the National R&D Program (Future-Oriented R&D Convergence Science and Technology Development Program (Bridge Convergence Research): Development of a skin patch for wound treatment integrating bio-tissue adhesive patches with drug delivery and phototherapy OLED therapy, the Technology Innovation Program supported by the Ministry of Trade, Industry and Energy (development of substrate materials stretchable by more than 50% for stretchable displays), and the BK21 FOUR Program of the Ministry of Science and ICT (Connected AI Education & Research Program for Industry and Society Innovation, School of Electrical Engineering, KAIST). (2021M3C1C3097646, 20017569, 4120200113769)