# Integration of Carbon Nanotubes into Manganese Dioxide Nanorods for Enhanced Enzymeless Electrochemical Glucose Sensing with High Sensitivity and Selectivity

## TL;DR

This study creates a new glucose sensor using carbon nanotubes and manganese dioxide to improve sensitivity and durability for real-time monitoring.

## Contribution

A freestanding CNTs/MnO2 electrode is developed for enzymeless glucose sensing with high sensitivity and selectivity.

## Key findings

- The electrode achieves a sensitivity of 309.73 µA cm−2 mM−1 with a wide linear range of 0.5 to 10 mM.
- It shows excellent selectivity and antifouling properties in complex biological samples.
- The design offers durability and scalability for real-time glucose monitoring.

## Abstract

Freestanding electrode designs, cost-effective catalysts, and enhanced electrical conductivity are crucial for improving the performance of fourth-generation non-enzymatic glucose electrochemical sensors. These factors enable more efficient, scalable, and durable sensors with better sensitivity, stability, and affordability for real-time glucose monitoring. In this study, we explore a freestanding electrode design combining carbon nanotubes (CNTs) with MnO2 nanorods to enhance charge transfer, increase surface area, and optimize catalytic activity. This CNTs/MnO2 electrode demonstrates exceptional catalytic activity for glucose oxidation, achieving a high sensitivity of 309.73 µA cm−2 mM−1 within a linear range of 0.5 to 10 mM—well above typical physiological glucose levels (3–8 mM), with a detection limit of 0.19 mM at a signal-to-noise ratio of 3. The electrode also shows excellent durability and remarkable selectivity for glucose over common interferents like ascorbic acid and uric acid, as well as antifouling properties in the presence of KCl. These attributes are essential for accurate glucose detection in complex biological samples. The integration of MnO2 nanorods with CNTs in freestanding nanostructures opens up exciting opportunities for developing high-performance, robust electrochemical sensors for diverse applications.