A Wearable Photobiomodulation Patch Using a Flexible Red‐Wavelength OLED and Its In Vitro Differential Cell Proliferation Effects

Abstract

Photobiomodulation (PBM) is a safe and noninvasive method that can provide various clinical effects. However, conventional PBM devices using point light sources, such as light‐emitting diodes and lasers have various disadvantages, such as low flexibility, relatively heavy weight, and nonuniform effects. This paper presents a novel wearable PBM patch using a flexible red‐wavelength organic light‐emitting diode (OLED) surface light source, which can be attached to the human body as a personalized PBM platform. The palm‐sized wearable PBM patch can be very light (0.82 g) and thin (676 µm). It also has a reasonable operation life (>300 h), flexibility (20 mm bending radius), and low‐temperature operation (<40 °C), and it can provide wide and safe application irrespective of location and time. Fibroblasts, a major type of dermal cells, play a key role in the wound healing process. The results show that OLEDs may have excellent in vitro wound healing effects because they effectively stimulate fibroblast proliferation (over 58% of control) and enhance fibroblast migration (over 46% of control) under various conditions. For maximum effect, peak wavelength control is necessary to optimize cell proliferation and enhance in vivo wound healing effects.

22‐4: Wearable Photobiomodulation Patch using Attachable Flexible Organic Light‐Emitting Diodes for Human Keratinocyte Cells

“…Attachable flexible OLEDs based on ultrathin films, which can be transferred for use as wearable light treatment modalities in various fields, are a current research issue [10,11]. Wearable PBM patches are designed to ensure reliable attachment to the human body while maintaining good flexibility.…”

“…Attachable flexible OLEDs with peaks at 630-690nm are reportedly more effective when used to promote the proliferation and migration of human fibroblasts as compared to 630nm LED arrays [10,11]. A cell-migration test [13] experiment was conducted to investigate whether the fabricated flexible OLED PBM patch would in fact have a phototherapeutic effect on human keratinocyte cells.…”

P‐98: Improved Cell Proliferation Effect on the Human Fibroblast by the Irradiation of Aging Processed PLEDs

“…To verify how the PLEDs could be effective on photobiomodulation, light irradiation was carried out on cultured human fibroblasts. In particulate, a unique OLED jig that had been produced in our previous work was used for the irradiation set-up [4]. Furthermore, 6-well plates and 96-well plates were used for a cytotoxicity test and a proliferation test, respectively.…”

“…In this regard, organic light-emitting diodes (OLEDs) have attracted interest from many researchers and engineers in that they are suitable for fabrication on various substrates, such as thin plastics and textiles [2,3]. Recently, a medical patch using thermally evaporated OLEDs was developed, and the device showed a remarkable in vitro wound healing effect [4]. Although this research is encouraging since OLED devices have a similar or greater effect on treating wounds than LED-based devices, issues involved in large-scale processibility must be addressed for the commercialization of OLEDs.…”

Flexible organic light‐emitting‐diode‐based photonic skin for attachable phototherapeutics

“…4 Accordingly, various studies are being actively conducted using flexible OLEDs, 5,6 for example, in oximeter sensors 7 and light therapy. 8,9 Among the various photonic skin-based healthcare applications, they have recently been studied for phototherapeutics because the technique is noninvasive, can be used for various effects, and is safe. OLEDs are considered to be the best light source candidates for skin-like photonic devices.…”