Spectroelectrochemical and computational studies of tetrahydrocannabinol (THC) and carboxy-tetrahydrocannabinol (THC-COOH).

Rapid and accurate detection of tetrahydrocannabinol (THC) and its main secondary metabolite carboxy-tetrahydrocannabinol (THC-COOH) is important to ensure safe roadways and workplaces, particularly in regions of the world where cannabis use is legal. In this work, we seek to demonstrate the usefulness of electrochemical SERS (EC-SERS) for the rapid detection of both THC and THC-COOH, complemented by thorough ab initio calculations for both molecules. These results indicate that application of a voltage is essential for efficient SERS detection of cannabinoids at low concentrations in bodily fluids, allowing for the eventual development of sensitive and quantitative screening tools. To the best of our knowledge, this work represents the first EC-SERS study of both THC and THC-COOH.

Development of an electrochemical surface-enhanced Raman spectroscopy (EC-SERS) fabric-based plasmonic sensor for point-of-care diagnostics.

Early disease diagnosis is crucial for timely and effective healthcare monitoring and treatment. Demand for modern point-of-care (POC) technologies has increased during the past decade. Continuous monitoring of patient health status can be achieved through wearable sensors which can be incorporated into clothing and other wearables. While electronic textiles that monitor physical parameters (heart rate, blood pressure, etc.) are increasingly commonplace, smart textiles capable of monitoring chemical biomarkers are much less common. In this work, a conductive plasmonic electrochemical sensor was developed from a cotton blend fabric modified with silver nanoparticles and conductive inks. para-Aminothiophenol (pATP) was used as an initial probe molecule to evaluate the performance of the fabric-based electrode for electrochemical surface-enhanced Raman spectroscopic (EC-SERS) measurements. Further investigation was then carried out to detect levofloxacin, a commonly prescribed antibiotic, in both 0.1 M NaF and synthetic urine as supporting electrolyte. It was found that the fabric-based electrode provided excellent EC-SERS signals, comparable to commercial screen-printed electrodes, allowing for rapid detection of levofloxacin at clinically relevant concentrations. To the best of our knowledge, this is the first time a fabric-based electrode has been reported for EC-SERS investigations, highlighting a promising platform for wearable point-of-care sensors.