A Disposable Sensor Chip Using a Paste Electrode with Surface-Imprinted Graphite Particles for Rapid and Reagentless Monitoring of Theophylline

Abstract

This work focuses on a carbon-based imprinted polymer composite, employed as a molecular recognition and sensing interface in fabricating a disposable electrochemical sensor. The carbon-paste electrode was made of a molecularly imprinted polymer comprising a copolymer of methacrylic acid as the functional monomer and blended crosslinking monomers of N,N′-methylenebisacrylamide, and ethylene glycol dimethacrylate, with theophylline as the template. The analytical properties of the proposed theophylline sensor were investigated, and the findings revealed an increase in differential pulse voltammetric current compared to the non-imprinted electrode. Under optimized conditions, the sensor has shown high sensitivity, high selectivity, lower detection limit (2.5 µg/mL), and satisfactory long-term stability. Further, the sensor was tested in whole bovine blood and validated without any matrix effect and cross-reactivity. Additionally, chronoamperometry of the sensor chip supported a rapid determination of THO with a short response time of 3 s. This carbon-paste electrode is highly specific for theophylline and may be applied as a drug sensor for clinical use.

Disposable Sensor Chips with Molecularly Imprinted Carbon Paste Electrodes for Monitoring Anti-Epileptic Drugs

“…Thus, the MIP sensor for LEV can be implemented for further analysis. Additionally, we observed that the same DPV parameters may only work for some types of MIP sensors [ 21 ]. Therefore, parameter optimization may also be a crucial step in finding the sensitivity of the sensor.…”

“…Carbon paste electrodes are a mixture of graphite powder and a conducting binder. The high surface area for electron transfer and porous structure of the carbon paste electrode makes it particularly well-suited for the electrochemical analysis [ 18 , 19 , 20 , 21 , 22 ]. Carbon-based electrodes are modified by adding chemical or biological components to their surfaces to improve electrochemical performance.…”