# Atom‐by‐Atom Multimetal CuMoP Deposition on Carbon Electrodes for Sensitive Antidiabetic Metformin Electrooxidation

## TL;DR

A new sensor made from a Cu–Mo–P nanocomposite on carbon electrodes can detect metformin with high sensitivity and selectivity for pharmaceutical use.

## Contribution

A ternary Cu–Mo–P nanocomposite is developed for sensitive metformin detection with low detection limits and high selectivity.

## Key findings

- The CuMoP/SPCE sensor achieved a linear detection range of 0.99–13.82 µM for metformin.
- The sensor had a low detection limit of 0.85 µM and showed excellent selectivity and stability.
- Recoveries of 94.32%–107.23% were achieved in pharmaceutical samples with minimal interference.

## Abstract

An atom‐by‐atom ternary Cu–Mo–P nanocomposite was electrochemically co‐deposited onto screen‐printed carbon electrodes (SPCEs) to form a highly active sensing interface for the determination of metformin (MF). The one‐step anodic fabrication yielded a porous, uniformly distributed network of mixed‐valence Cu+/Cu2+ and Mo6+ centres embedded within a phosphate‐stabilized matrix. Comprehensive microstructural and spectroscopic analyses revealed enhanced surface roughness, expanded electroactive area and favourable charge‐transfer characteristics. The CuMoP/SPCE exhibited markedly amplified redox activity and proton‐coupled electron‐transfer behaviour toward MF, enabling sensitive detection with a linear range of 0.99–13.82 µM and a low detection limit of 0.85 µM. Excellent selectivity, stability and reproducibility were achieved, with recoveries of 94.32%–107.23% in pharmaceutical samples and negligible interference from common ions or saccharides. These results demonstrate the synergistic catalytic contributions of Cu, Mo and P in enabling efficient electron mediation, positioning the CuMoP/SPCE robust, low‐cost platform for rapid pharmaceutical quality control and therapeutic monitoring.

An atom‐by‐atom ternary Cu–Mo–P nanocomposite is electrochemically co‐deposited onto screen‐printed carbon electrodes to create a highly active sensing interface for metformin detection. The porous mixed‐valence network enhances electroactive surface area and charge transfer, enabling sensitive and selective electrooxidation with a low detection limit. The platform demonstrates reliable performance in pharmaceutical samples for rapid therapeutic monitoring.