MOLECULARLY IMPRINTED WEARABLE SENSOR WITH PAPER MICROFLUIDICS FOR REAL TIME SWEAT BIOMARKER ANALYSIS

Smart overview of the Invention

The patent application describes a wearable biosensor designed for real-time analysis of biomarkers in sweat. The device integrates several functional modules, including an iontophoresis induction module, a microfluidic layer, multiple multimodal biosensors, and a paperfluidic layer. This innovative approach allows for effective and non-invasive monitoring of various health parameters by analyzing sweat, which reflects biochemical changes in the body.

Technical Background

Wearable sensors are crucial for personalized health monitoring, particularly for detecting low concentrations of biomarkers like cortisol, a stress hormone. Traditional methods using antibodies or aptamers face challenges such as reliance on redox probes and potential toxicity. Sweat is an ideal biofluid for continuous monitoring due to its ability to reflect physiological changes. However, the low volume of sweat secretion demands sensitive microfluidic devices for collection and analysis.

Device Components

The wearable biosensor comprises several key components. The iontophoresis induction module includes two laser-induced graphene (LIG) electrodes coated with hydrogels to stimulate sweat production. These electrodes are fabricated on a polyimide sheet and function as anode and cathode to form an electrical circuit. The microfluidic layer features an inlet layer made of skin adhesive material with openings for direct contact with the skin, enabling efficient biofluid collection and analysis.

Functional Mechanism

The device employs a paper wicking layer to remove accumulated biofluid post-analysis, preventing contamination of subsequent samples. This layer comprises chromatography paper and connects to the paperfluidic module. The biosensor is encapsulated with skin adhesive to minimize evaporation and environmental contamination. The device's electrodes are configured for specific tasks; one detects cortisol using a Molecularly Imprinted Polymer (MIP) coating, while another quantifies sodium ion concentration using an ion-selective membrane.

Applications and Advantages

This flexible wearable device can measure multiple parameters such as sweat volume, secretion rate, sodium ion concentration, and cortisol levels without requiring user intervention to reset the sensing chamber. By employing electrochemical impedance spectroscopy (EIS), the MIP-based sensor offers high sensitivity without needing labels or redox probes. This approach simplifies the sensor design while maintaining accuracy, making it suitable for continuous health monitoring in real-world applications.