A wearable lab-on-a-patch platform with stretchable nanostructured biosensor for non-invasive immunodetection of biomarker in sweat

Conformable, wearable biosensor-integrated systems are a promising approach to non-invasive and quantitative on-body detection of biomarkers in body fluids. However, realizing such a system has been slowed by the difficulty of fabricating a soft affinity-based biosensor patch capable of precise on-body fluid handling with minimal wearer intervention and a simple measurement protocol. Herein, we demonstrate a conformable, wearable lab-on-a-patch (LOP) platform composed of a stretchable, label-free, impedimetric biosensor and a stretchable microfluidic device for on-body detection of the hormone biomarker, cortisol. The all-in-one, stretchable microfluidic device can precisely collect and deliver sweat for cortisol quantitation and offers one-touch operation of reagent delivery for simultaneous electrochemical signal generation and washing. Three-dimensional nanostructuring of the Au working electrode enables the high sensitivity required to detect the pM-levels of cortisol in sweat. Our integrated LOP detected sweat cortisol quantitatively and accurately during exercise. This LOP will open a new horizon for non-invasive, highly sensitive, and quantitative on-body immunodetection for wearable personal diagnostics. Stretchable 3D nanostructured biosensor was integrated with microfluidics in lab-on-a-patch platform. The patch has the capability of autonomous sweat sampling and reagent delivery by one-touch finger operation for impedimetric signal reading and can measure human sweat cortisol non-invasively and quantitatively. The patch shows great promise for wearable immunosensor. [Display omitted] •Stretchable microfluidic system for sweat sampling to measurement.•3D nanostructured gold working electrode for highly sensitive and stretchable impedimetric biosensor.•Lab-on-a-patch platform integrated with stretchable impedimetric biosensor and microfluidic system.•Demonstration of on-body immunodetection of sweat cortisol.