Multiplex Chroma Response Wearable Hydrogel Patch: Visual Monitoring of Urea in Body Fluids for Health Prognosis

Visual wearable devices can rapid intuitively monitor biomarkers in body fluids to indicate the human health status and provide valuable reference for further medical diagnosis. However, unavoidable interference factors such as skin color, natural light, and background luminescence can interfere with the visualization accuracy of flexible wearable devices, limiting their practical sensing application. Here, we designed a wearable sensing patch via an embedded upconversion optical probe in a 3D porous polyacrylamide hydrogel, exhibiting a multiplex chroma response to urea based on the inner filter effect, which overcomes the susceptibility to external conditions due to its near-infrared excited luminescence and improves the resolution and accuracy of visual sensing. Furthermore, a highly compatible portable sensing platform combined with a smartphone was designed to achieve in situ rapid quantitative analysis of urea. The limit of detection values of the upconversion optical probe and hydrogel sensor are as low as 1.4 and 30 mu M respectively, exhibiting the practicality in different scenarios. The designed sensing patch provides a convenient and accurate sensing strategy for the detection of biomarkers in body fluids and has the potential to be developed into a point-of-care device to provide disease early warning and clinical diagnosis.

Automated summary

Visual wearable devices can monitor biomarkers in body fluids intuitively and accurately, providing valuable reference for medical diagnosis. By embedding an upconversion optical probe in a 3D porous polyacrylamide hydrogel, a wearable sensing patch with multiplex chroma response to urea has been designed, which overcomes the interference factors and improves the accuracy of visual sensing. A portable sensing platform combined with a smartphone enables in situ rapid quantitative analysis of urea, highlighting the practicality of the design. This sensing patch offers a convenient and accurate strategy for biomarker detection and has the potential to be used as a point-of-care device for disease early warning and clinical diagnosis.