Wearable modular microfluidic sensing system inspired by traditional Chinese mortise-tenon joints for sweat sensing applications

Wearable microfluidic sweat biosensors have drawn great attention for their noninvasive ability to detect various biomarkers in human sweat. However, traditional microfluidic biosensors are always complicated and inflexible, limiting modification after production. This work proposed a cost-effective and easy-to-fabricate method inspired by traditional Chinese mortise-tenon structure joints to develop a wearable modular sweat sensing system without glue, nails, or any other materials. Both electrochemical sensors and colorimetric sensors can be integrated into the wearable modular microfluidic sensing system to meet different requirements. The proposed microfluidic sensing system can avoid flow-through mixing effects using capillary bursting valves and detect pH, together with Na⁺ and Cl⁻ in collected sweat. The detected biomarkers can be added or changed in this microfluidic sensing system according to distinct applications. Therefore, this work provides a novel way to fabricate multifunctional wearable sensing systems and sheds light on the future of point-of-care testing and personalized healthcare.