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

Area of Science:

• Electrochemistry
• Materials Science
• Analytical Chemistry

Background:

• Molecularly imprinted polymers (MIPs) are crucial for creating selective recognition sites.
• Electrochemical sensors offer sensitive and rapid detection methods.
• Accurate theophylline monitoring is vital in clinical settings.

Purpose of the Study:

• To develop a disposable electrochemical sensor for theophylline detection.
• To utilize a carbon-based molecularly imprinted polymer composite as the sensing interface.
• To evaluate the sensor's analytical performance and applicability in biological matrices.

Main Methods:

• Fabrication of a carbon-paste electrode modified with a MIP composite.
• Synthesis of the MIP using methacrylic acid, crosslinking monomers, and theophylline as a template.
• Electrochemical characterization using differential pulse voltammetry and chronoamperometry.
• Validation in whole bovine blood samples.

Main Results:

• The imprinted electrode exhibited enhanced differential pulse voltammetric current compared to the non-imprinted electrode.
• The sensor demonstrated high sensitivity, selectivity, a low detection limit (2.5 µg/mL), and good stability.
• The sensor showed no matrix effects or cross-reactivity when tested in whole bovine blood.
• Chronoamperometry enabled rapid theophylline determination with a 3-second response time.

Conclusions:

• The developed carbon-based MIP sensor is highly specific and sensitive for theophylline detection.
• The disposable electrochemical sensor is suitable for rapid and accurate theophylline determination in whole blood.
• This sensor holds potential for clinical drug monitoring applications.