Hydrocolloid‐Based Multiwavelength Stretchable QD‐OLED Patch for Simultaneous Neonatal Jaundice and Dermatitis Treatment with Biosignal Monitoring

Conventional light-emitting-diode-based light sources suffer from rigidity, localized heating, and poor adaptability to skin deformation, limiting their use in skin-attached medical devices. To address these challenges, a quantum dot organic light-emitting diode (QD-OLED) architecture utilizing a blue OLED with QD for wavelength conversion is developed, achieving dual-wavelength emission (470 and 630 nm) in a simplified structure. The use of hydrocolloid as a substrate ensures skin adhesion, moisture retention, and attachability. The device exhibits high mechanical resilience with 190% stretchability and stable optical performance under deformation for over 80 h at low temperatures (<39 °C). By combining photomedicine functionality with flexibility, the platform demonstrates 26% bilirubin degradation under blue light and 46% human skin keratinocyte (HaCaT) cell proliferation under red light. Furthermore, the integration of organic photodiodes enables real-time biosignal detection, such as photoplethysmography, expanding the platform's potential in personalized healthcare systems. This study highlights the convergence of emerging electronic materials, QD-OLED, stretchable substrates, and organic sensors as a viable route for next-generation medical devices that integrate treatment, sensing, and skin-conformal mechanics in a single patch-type system.