Polypyrrole-coated carbon fibre electrodes for paracetamol and clozapine drug sensing

Advancements in Flexible Sensors for Monitoring Body Movements during Sleep: A Review

Sleep plays a role in maintaining our physical well-being. However, sleep-related issues impact millions of people globally. Accurate monitoring of sleep is vital for identifying and addressing these problems. While traditional methods like polysomnography (PSG) are commonly used in settings, they may not fully capture natural sleep patterns at home. Moreover, PSG equipment can disrupt sleep quality. In recent years, there has been growing interest in the use of sensors for sleep monitoring. These lightweight sensors can be easily integrated into textiles or wearable devices using technology. The flexible sensors can be designed for skin contact to offer continuous monitoring without being obtrusive in a home environment. This review presents an overview of the advancements made in flexible sensors for tracking body movements during sleep, which focus on their principles, mechanisms, and strategies for improved flexibility, practical applications, and future trends.

An inexpensive paracetamol sensor based on an acid-activated carbon fiber microelectrode

Paracetamol, a contaminant of emerging concern, has been detected in different bodies of water, where it can impact ecological and human health. To quantify this paracetamol, electroanalytical methods have gained support. Thus, the present study developed a simple, inexpensive, and environmentally friendly method for paracetamol quantification using a carbon fiber microelectrode based on commercial carbon fiber. To improve the carbon fiber microelectrode's paracetamol sensitivity and selectivity, it was subjected to an activation process via electrochemical oxidation in an acid medium (H2SO4 or HNO3), using 20 consecutive cycles of cyclic voltammetry. The treated (activated) carbon fiber microelectrode was characterized using scanning electron microscopy and electrochemical techniques, including chronoamperometry and electrochemical impedance spectroscopy. The H2SO4-activated carbon fiber microelectrode exhibited enhanced figures of merit, with a linear dynamic range of paracetamol detection from 0.5 to 11 μmol L-1 and a limit of detection of 0.21 μmol L-1 under optimized conditions. The method was optimized by quantifying paracetamol in commercial pharmaceutical tablets, spiked running tap water, and river water (Pita River, Quito, Ecuador, latitude -0.364955°, longitude -78.404538°); the respective recovery values were 102.89, 103.93, and 112.40%. The results demonstrated an acceptable level of accuracy and the promising applicability of this carbon fiber microelectrode as a sensor to detect paracetamol.

Electrochemistry Test Strip as Platform for In Situ Detection of Blood Levels of Antipsychotic Clozapine in Finger-Pricked Sample Volume

With the increasing number of patients suffering from Parkinson's disease, the importance of measuring drug levels in patient body fluids has increased exponentially, particularly for the drug clozapine. There is a growing demand for real-time analysis of biofluids on a single low-cost platform in ultra-low fluid volumes with robustness. This study aims to measure the level of clozapine (Clz) with a portable potentiostat using a practical approach. For this purpose, we developed an inexpensive, portable platform via electrochemistry on a commercial glucose test strip (CTS). CTSs were first modified by removing the enzyme mixture from the surface of the sensing zone, which was followed by modification with Multi walled carbon nanotube (MWCNT) and Nafion. The electrochemical characteristics of CTS electrodes were investigated using cyclic voltammetry (CV) and differential voltammetry (DPV) techniques. The designed sensor displayed decent linear range, detection limit, reproducibility, and reusability results. A linear dynamic range of 0.1-5 μM clozapine was observed under optimized conditions with a good sensitivity (1.295 μA/μM) and detection limit (83 nM). Furthermore, the designed sensing electrode was used to measure the amount of Clz in real samples.