Traditional Korean paper becomes breathable patch for future wearable health care

Traditional Korean paper becomes breathable patch for future wearable health care Swati Mestri Scientific Editor Robert Egan Senior Editor Wearable health-monitoring devices are becoming increasingly important for personalized health care, but conventional patches often rely on substrates that restrict airflow, trap sweat and cause skin discomfort during prolonged use. These limitations can also interfere with the reliable collection and analysis of sweat, highlighting the need for breathable materials that support both comfortable wear and accurate sensing. Addressing this challenge, researchers led by professor Sooman Lim at Jeonbuk National University, South Korea, have developed a breathable wearable patch using traditional Korean mulberry paper, known as hanji. The platform combines 3D-printed microneedles for potential drug delivery with printed electrodes for wireless uric acid sensing. The study, published in Chemical Engineering Journal, demonstrates the feasibility of incorporating both functions into a single paper-based platform. The first authors of the study are Aqila Che Ab Rahman and Habibulla Imran, who contributed equally. "Conventional wearable patches often struggle to balance skin comfort with reliable sweat collection. By using breathable mulberry paper, we aimed to develop a platform that supports moisture transport while accommodating both microneedles and printed sensing electrodes," says Lim of Jeonbuk National University. Porous paper supports drug-delivery microneedles Unlike impermeable substrates, mulberry paper has a porous network of plant fibers that promotes moisture transport. In experiments, the porous paper sample showed rapid wetting, with its water contact angle decreasing from 72.19° to 7.96° within six seconds. This property could help manage sweat accumulation while supporting its transport toward sensing electrodes. The researchers fabricated microneedles directly on the mulberry paper substrate using light-based 3D printing, without requiring an additional adhesive layer. By modifying the microneedle geometry, they improved drug-loading capacity. The optimized microneedles achieved a drug loading of 25.36%, compared with 12.6% for unmodified microneedles, and released 56.41% of the loaded model dye over 80 hours. They also penetrated approximately 954 micrometers into excised rat skin without structural deformation. These findings highlight the patch's potential for future drug-delivery applications. Wireless uric acid sensing in sweat The printed electrochemical sensor detected uric acid across concentrations ranging from 0.01 to 8 micromolar, with a detection limit of 9.3 nanomolar. Tests using buffer and sweat samples yielded recoveries of 98.1%–101.3% that agreed with laboratory LC-MS analysis, demonstrating the sensor's analytical performance. Additionally, the sensor dried within 13 seconds after use and gave consistent readings over three consecutive uses. A low-power wireless system also enabled transmission of sensing data, with the wireless board drawing only about 15 mW at peak—lower than earlier wearable IoT biosensors (60 to 120 mW). Uric acid is a key marker for gout and hyperuricemia. A sweat-based patch could let people check their uric acid at home without repeated blood draws and could help track how uric acid responds to medicines, since some drugs raise uric acid while others lower it. On-body testing and drug trials ahead "Our findings demonstrate the potential of combining microneedle-based delivery and wireless sweat sensing on a single breathable substrate. Although we evaluated these functions separately, the results provide a foundation for future devices that could integrate treatment and real-time health monitoring," explains Lim. Next, the team plans to test the patch with clinically relevant uric acid–lowering drugs, together with skin-safety studies and real-time testing on the body. By bringing microneedle fabrication and wireless sweat sensing onto a breathable paper substrate, the research establishes a foundation for future wearable technologies that could make treatment and health monitoring more convenient, comfortable and personalized. Publication details Aqila Che Ab Rahman et al., Breathable mulberry paper-based theranostic patch integrating 3D-printed microneedles for drug delivery and wireless sweat-wicking uric acid sensing, Chemical Engineering Journal (2026). DOI: 10.1016/j.cej.2026.178008 Journal information: Chemical Engineering Journal Provided by Jeonbuk National University