Key Findings
A breakthrough study published in ACS Omega reports the successful development of a highly stable wearable DNA aptamer sensor for the non-invasive, continuous monitoring of cortisol in artificial sweat. This innovative sensor is based on a screen-printed electrode modified with a gold nanoparticle–carboxymethyl cellulose–methylene blue interface. The sensor demonstrated exceptional reproducibility, with relative standard deviations (RSDs) of 4.8% for oxidation peak current and 4.3% for reduction peak current. It achieved an ultra-sensitive limit of detection (LOD) of 0.09 pg/mL and a wide linear range from 0.0001 to 1000 ng/mL. Furthermore, the sensor exhibited remarkable long-term stability, retaining 93.4% of its initial response after 56 days of storage, a critical factor for practical wearable applications.
Technical & Clinical Details
The high performance of this sensor is attributed to the specific binding capability of DNA aptamers immobilized on the electrode surface to cortisol, combined with an optimized electrochemical signal amplification mechanism mediated by the gold nanoparticles, carboxymethyl cellulose, and methylene blue. Methylene blue acts as a redox probe, detecting electrochemical signal changes resulting from structural alterations when cortisol binds to the aptamer. The use of screen-printed electrodes enables low-cost, mass production, facilitating easy integration into wearable devices. Its extremely low detection limit allows for precise capture of minute cortisol concentration changes in sweat, providing crucial information for stress level monitoring and early diagnosis of conditions like adrenal dysfunction. The 56-day long-term stability significantly reduces the need for frequent sensor replacement, greatly enhancing its practicality and user convenience.
Background & Context
Cortisol, known as the ‘stress hormone,’ is intimately linked to stress levels, sleep patterns, and various disease states. Non-invasive cortisol monitoring has been a key target for wearable biosensors due to its potential to reduce patient burden and enable real-time health assessment. However, the very low concentration of cortisol in sweat and its susceptibility to interference from other components have made the development of highly sensitive and long-term stable wearable sensors challenging. This research successfully overcomes these hurdles, poised to significantly impact the personal health monitoring market.
Strategic Significance & Outlook
The success of this wearable electrochemical aptamer sensor opens new avenues for non-invasive diagnostics. Future developments are expected to build upon this technology to create multi-functional wearable sensors capable of simultaneously detecting other biomarkers, such as glucose, lactate, and electrolytes. Furthermore, integrating collected biometric data with AI for analysis could lead to personalized healthcare systems that comprehensively understand individual health status and predict early signs of disease. This technology holds immense promise for diverse applications, including sports medicine, astronaut health management, and remote monitoring of chronic diseases, offering global impact for continuous health surveillance.
Source: https://pubs.acs.org/doi/10.1021/acsomega.6c05341
Get our weekly technology intelligence — free
Receive an infographic that lets you judge at a glance whether each field’s analysis report is worth reading.
Subscribe Free — Weekly Tech Intelligence
By subscribing, you’ll receive Troy-Technical’s weekly technology intelligence newsletter.
- Your email and selected fields are used only to deliver the newsletter.
- We never share your information with third parties.
- You can unsubscribe anytime via the link in each email.
See our Privacy Policy for details.
Takes about a minute · Unsubscribe anytime
Comments