ERI: In-Situ Fabrication of Dual-Template Imprinted Nanocomposites for Simultaneous Detection of Glucose and Cortisol

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2).

People with diabetes are 2-3 times more likely to have depression than people without diabetes. Meanwhile, depressive or anxiety symptoms, often associated with elevated cortisol (the “stress hormone”), can lead to the onset of type 2 diabetes (T2D). Monitoring both glucose and cortisol levels regularly in a cost-effective and effortless way is highly desired to manage diabetes and stress, and prevent prediabetes from progressing to full-blown T2D.

Enzyme-based glucose sensors monopolize the current glucose monitor industry, and the traditional detection of cortisol is carried out in centralized laboratory settings based on immunoassays using antibodies and enzymes. Natural receptors such as enzymes and antibodies often suffer from high cost, poor stability, and complexity. This project aims to develop an enzyme-free and antibody-free electrochemical sensor to simultaneously detect glucose and cortisol coupled with machine learning techniques.

The knowledge gained from this research will lead to low-cost biosensing devices and manufacturing processes that will not only increase access to decentralized, personalized, and preventive healthcare but may also be applied to other chemicals, biomarkers, and pathogens detection. This project will contribute significantly to workforce training by promoting the interdisciplinary research of sensing, computing, and machine learning-based data analytics.

The investigator’s long-term research goal is to develop a low-cost, easy-to-manufacture and high-performance biosensing technology based on electropolymerized MIPs (e-MIPs) as the platform to detect biomarkers in human biofluids for decentralized diagnostics and personal health monitoring. Towards this goal, the aim of this ERI project is to pilot an in-situ fabrication procedure to construct an enzyme-free and e-MIPs-based electrochemical sensor to simultaneously detect glucose and cortisol with high sensitivity and selectivity.

The proposed sensor consists of metal/metal oxide (M/MO) nanostructures to mimic enzymes’ catalytic activity for glucose oxidation and a molecularly imprinted polymer (MIP) to mimic antibodies’ selective biomolecular recognition for glucose and cortisol. The project will explore a fully in-situ fabrication procedure to synthesize and integrate functional nanomaterials with MIPs directly on the electrode’s surface.

This process is fast, facile, and highly reproducible, and the sensor is immediately ready for use without further processing. The proposed sensor is designed to provide distinct dual signals correlated with cortisol and glucose concentrations, which can be quantified simultaneously by a well-configured machine learning model. The novel dual-sensing mechanism will establish a new path to enable multiplex detection leveraging upon the powerful inference capability of machine learning.

This project will also deliver an in-depth understanding of the critical factors that impact the sensing performance, which will provide valuable guidelines for future MIPs design for biosensors. Low cost and high performance of MIPs, facile fabrication process, microfluidic-integration readiness, and multiplex detection capability all together will lead to cost-effective biosensors and biodevices not only for Point-of-Care (POC) diagnosis and personal health monitoring but also for other applications such as smart agriculture, water quality, and food safety monitoring.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.