Wearable and Wavelength-Tunable Near-Infrared Organic Light-Emitting Diodes for Biomedical Applications

Area of Science:

• Materials Science
• Biomedical Engineering
• Optoelectronics

Background:

• Near-infrared organic light-emitting diodes (NIR OLEDs) offer potential for wearable phototherapy due to their flexibility and NIR emission properties.
• Previous NIR OLEDs often used brittle indium tin oxide (ITO) electrodes, limiting their use in wearable applications.
• Developing robust, flexible NIR OLEDs is crucial for advancing wearable biomedical devices.

Purpose of the Study:

• To create wearable, wavelength-tunable NIR OLEDs.
• To replace traditional brittle ITO electrodes with flexible silver (Ag) electrodes.
• To evaluate the efficacy of these NIR OLEDs in promoting cell proliferation for phototherapy.

Main Methods:

• Fabrication of NIR OLEDs utilizing a high-performance NIR emitter and silver electrodes.
• Wavelength tuning of NIR emissions between 700 and 800 nm.
• In vitro testing of NIR OLEDs on human hair follicle dermal papilla cells, comparing results with visible light OLEDs.

Main Results:

• The developed NIR OLEDs are wearable, wavelength-tunable (700-800 nm), and stable under bending.
• Devices exhibited stable operation with a lowered temperature (37.5 °C) during continuous use.
• NIR irradiation significantly promoted cell proliferation, exceeding the effects of visible light irradiation.
• Cell proliferation was dependent on irradiation wavelength and duration.

Conclusions:

• Wearable, wavelength-tunable NIR OLEDs using silver electrodes are feasible and practical for biomedical applications.
• These NIR OLEDs demonstrate significant potential for effective phototherapy by enhancing cell proliferation.
• The findings open new possibilities for advanced wearable phototherapeutic devices.