# Sensitive voltammetric detection of bosentan using gold nanoparticles-decorated pencil graphite electrode in pharmaceutical formulations and plasma samples

## TL;DR

A new eco-friendly electrochemical sensor using gold nanoparticles on a pencil graphite electrode was developed to detect bosentan in pharmaceuticals and plasma with high accuracy.

## Contribution

The study introduces a sensitive and green electrochemical method for bosentan detection using gold nanoparticle-modified electrodes.

## Key findings

- The sensor achieved a dynamic range of 2.5 × 10−7 to 2.5 × 10−5 M with a detection limit of 7.92 × 10−8 M.
- The method was validated for accuracy and precision in pharmaceutical dosage forms and human plasma.
- The analytical method received a high greenness score of 78.0 and an AGREE score of 0.65.

## Abstract

In this study, a new eco-friendly electrochemical sensor was effectively designed and utilized to analyze bosentan (BOS); an endothelin receptor antagonist (ERA) that helps in the management of pulmonary artery hypertension (PAH), in its pharmaceutical dosage forms and in human plasma samples. Our approach involves BOS electro-oxidation on a gold nanoparticles- modified pencil graphite electrode (PGE) surface in order to improve electrode sensitivity and increase peak current. Gold nanoparticles (Au-NPs) were electrochemically deposited onto the electrode surface using cyclic voltammetry (CV). With the aid of differential pulse voltammetry, a quantitative determination of BOS was obtained in 0.1 M KCl across a potential range of 0.00 to 1.8 V. The method’s validation was performed in compliance with International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines, and the dynamic range of the proposed sensor was found to be (2.5 × 10− 7–2.5 × 10− 5) M with a limit of detection (LOD) of (7.92 × 10− 8) M. The sensor has been effectively utilized to determine BOS in its dosage form and human plasma with good accuracy and precision, and without any interference from the plasma matrix or tablet excipients. In addition, the method was assessed from a green perspective and was found to be of excellent greenness with an analytical eco-scale of 78.0. While AGREE software gave a score of 0.65 which indicates acceptable greenness.

The online version contains supplementary material available at 10.1038/s41598-026-42667-w.