Hybrid Functional Polymer-Enabled Multiplexed Chemosensor Patch for Wearable Adrenocortex Stress Profiling

Engineering electropolymerized molecularly imprinted polymer films for redox-integrated, reagent-free cortisol detection: The critical role of scan rate

Electropolymerized molecularly imprinted polymers (eMIPs) represent a versatile platform for electrochemical biosensing, offering tailored specificity, high stability, and cost-effectiveness through direct synthesis on electrodes. This study investigates the fabrication-property-performance relationship of eMIPs for enhanced cortisol biosensing, with a focus on the interplay between scan rate and the number of polymerization cycles during cyclic voltammetry-based electropolymerization. The thickness, density, and morphology of the eMIP films were systematically characterized using electrochemical quartz crystal microbalance (EC-QCM), field-emission scanning electron microscopy (FE-SEM), and profilometry. Lower scan rates (25 mV s-1) produced denser and smoother polymer film compared to higher scan rates (50 mV s-1), highlighting the critical influence of scan rate on polymer properties. The eMIP films fabricated with different parameters were integrated with a Prussian Blue nanoparticles layer on screen-printed carbon electrodes for reagent-free cortisol detection. Square wave voltammetry (SWV) was used to evaluate sensor performance, which demonstrates that lower scan rates (25 mV s-1) combined with increased polymerization cycle counts yielded a denser and thicker film, resulting in enhanced sensitivity and selectivity. The sensor achieved a limit of detection (LOD) of 26 pM for cortisol. These findings provide valuable insights into the critical role of electropolymerization parameters in tailoring film properties (i.e., thickness and density), enhancing eMIP sensor design, and advancing biosensor technology through precise control of electropolymerization parameters.

Cortisol and psychological responses to natural disasters

Natural disasters are an increasing global health issue. Psychological outcomes from traumatic experiences appear linked to the glucocorticoid hormone cortisol. Here we analyze relations among salivary cortisol, traumatic events, and mental health from a 37-year study of a rural community in Dominica. The community has experienced multiple natural disasters. Our investigations of physiological responses to these traumatic experiences and downstream mental health outcomes are exploratory in nature because this research area is in early stages of methodological and theoretical development, and we are applying current biomedical and psychiatric concepts in a non-western culture. Our analyses suggest that temporal profiles of cortisol response are linked to mental health conditions associated with natural disasters including grief, depression, and post-traumatic stress disorders.

Saliva-Sensing Dental Floss: An Innovative Tool for Assessing Stress via On-Demand Salivary Cortisol Measurement with Molecularly Imprinted Polymer and Thread Microfluidics Integration

On-demand dental-floss-based point-of-care platform is developed for the noninvasive and real-time quantification of salivary cortisol utilizing redox-molecule embedded molecularly imprinted polymer structures and thread microfluidics. Herein, we explore the high-surface-area graphene-based electrode substrate for electrochemically synthesizing selective cortisol MIPs and integrate it with thread microfluidics to build a highly sensitive cortisol-sensing platform for stress monitoring. This platform uses flossing to collect and transport saliva to a flexible electrochemical sensor via capillary microfluidics, where cortisol, a stress biomarker, is measured. This strategy allowed us to detect cortisol as low as 0.048 pg mL-1 in real-time with a detection range of 0.10-10,000 pg mL-1 (R2 = 0.9916). The saliva-sensing dental floss provides results within 11-12 min. The thread-based microfluidic design minimizes interference and ensures consistent repeatability when testing both artificial and actual human saliva samples, yielding 98.64-102.4% recoveries with a relative standard deviation of 5.01%, demonstrating high accuracy and precision. For the human saliva sample (as part of the stress study), the platform showed a high correlation (r = 0.9910) against conventional ELISA assays. Combined with a wireless readout, this saliva floss offers a convenient way to monitor daily stress levels. It can be extended to detect other critical salivary biomarkers with high sensitivity and selectivity in complex environments.

Smart Health Monitoring: Review of Electrochemical Biosensors for Cortisol Monitoring

Cortisol, also known as the stress hormone, is a crucial corticosteroid hormone that significantly increases secretion in the human body when facing notable stress. Monitoring cortisol levels is crucial for personal stress management and the diagnosis and treatment of certain diseases. Electrochemical biosensors combine the efficient sensitivity of electrochemical technology with the high specificity of biological recognition processes, making them widely applicable in the analysis of human body fluid components. This work outlines the working mechanism of cortisol electrochemical biosensors, focusing particularly on sensing elements such as antibodies, aptamers, and molecularly imprinted polymers. It provides detailed explanations of the operational principles of these different recognition elements. This work summarizes and evaluates the latest advancements in electrochemical biosensors for detecting cortisol in human body fluids, discussing the influence of different recognition elements on sensor design and electrochemical performance. Subsequently, through a comparative analysis of various sensor performances, the work further discusses the challenges in translating laboratory achievements into practical applications, including enhancing key metrics such as sensor reusability, reproducibility, long-term stability, continuous monitoring capability, and response time. Finally, it offers insights and recommendations for achieving real-time, continuous, and long-term monitoring with cortisol electrochemical biosensors.

Recent advances in nonenzymatic electrochemical biosensors for sports biomarkers: focusing on antibodies, aptamers and molecularly imprinted polymers

Nonenzymatic electrochemical biosensors, renowned for their high sensitivity, multi-target analysis capabilities, and miniaturized integration, align well with the requirements of non-invasive, multi-index integrated, continuous monitoring, and user-friendly wearable biosensors in sports science. In the past three years, novel strategies targeting specific responses to sports biomarkers have opened new avenues for applications in sports science. However, these advancements also pose challenges in achieving adequate sensitivity and specificity for online analysis of complex sweat bio-samples. Our article focuses on three key nonenzymatic electrochemical biosensing strategies: antigen-antibody reactions, nucleic acid aptamer recognition, and molecular imprinting capture. We delve into strategies to enhance specificity and sensitivity in the application of biosensors in sports science, including shortening signal transduction paths through built-in signal probes, increasing reaction sites through increased surface area and the introduction of nanostructures, multi-target analyses, and microfluidic techniques.

Clinical Endocrinology-Time for a Reset?

Measurement of blood levels of circulating hormones has always been the cornerstone of the biochemical diagnosis of endocrine diseases, with the objective of detecting hormone excess or insufficiency. Unfortunately, the dynamic nature of hormone secretion means single-point measurements of many hormones often lack diagnostic validity. Endocrinologists have devised complex dynamic tests as indirect assessments of the functioning of the hormone system under investigation. Recent advances in the measurement of dynamic hormone changes across the day now offer an opportunity to reconsider whether there might be better ways both to diagnose and to monitor the therapy of endocrine conditions.