An rGO-modified all-solid-state tetracaine-selective microsensor with enhanced interfacial stability for rapid
Ayman H Kamel1,2, Huda M Al-Radhi1, Hisham S M Abd-Rabboh3
1Department of Chemistry, College of Science, University of Bahrain Sakhir 32038 Kingdom of Bahrain ahkamel76@sci.asu.edu.eg.
RSC Advances
|August 1, 2026
Summary
A new all-solid-state microsensor using reduced graphene oxide (rGO) enhances tetracaine detection in eye drops. This graphene-based sensor offers improved stability and accuracy for pharmaceutical analysis.
Area of Science:
- Electroanalytical Chemistry
- Materials Science
Background:
- Accurate determination of tetracaine in ophthalmic formulations is crucial for quality control.
- Existing potentiometric sensors often face challenges with interfacial stability and reproducibility.
Purpose of the Study:
- To develop an all-solid-state tetracaine-selective microsensor with enhanced interfacial stability.
- To investigate the role of reduced graphene oxide (rGO) as an ion-to-electron transducer.
Main Methods:
- Fabrication of a microsensor using a glassy carbon substrate coated with rGO and a tetracaine-selective membrane.
- Potentiometric measurements to evaluate sensor performance, including linearity, detection limit, and selectivity.
- Chronopotentiometric studies to assess interfacial properties and water-layer formation.
Main Results:
- The rGO-modified microsensor achieved a near-Nernstian slope (59.1 mV/decade) and a low detection limit (5.49 × 10⁻⁷ mol L⁻¹).
- Enhanced interfacial stability, improved reproducibility, and superior charge-transfer behavior compared to unmodified sensors.
- Successful application in commercial ophthalmic formulations with high recovery rates (98.6-101.6%).
Conclusions:
- Reduced graphene oxide significantly improves the performance of potentiometric microsensors for pharmaceutical analysis.
- The developed microsensor is a simple, rapid, and cost-effective platform for tetracaine determination.
- Graphene-based solid-contact transducers offer a promising approach for enhancing pharmaceutical sensor technology.
