# Quantitative determination of al (III) traces in soft drink, pharmaceutical products and biological fluids of kidney failure and alzheimer disease patients using carbon sensor

## TL;DR

A new carbon sensor was developed to detect trace amounts of aluminum in drinks, medicines, and patient fluids, which could help in diagnosing and monitoring health conditions.

## Contribution

A novel carbon paste sensor using p-chlorophenyl maleanilic acid was developed for selective and sensitive Al(III) detection in various samples.

## Key findings

- The sensor has a detection limit of 3.3 × 10⁻⁷ mol L⁻¹ and a Nernstian slope of 20.32 ± 1.18 mV per decade.
- It shows high selectivity for Al(III) over other cations and can be used in pharmaceuticals, soft drinks, and biological fluids.
- The reaction mechanism was confirmed using FT-IR, SEM, and EDX analyses.

## Abstract

Carbon paste sensor based on p-chlorophenyl maleanilic acid (pCl-MA) as an ionophore was synthesized and investigated as an Al(III) ion selective sensor. The developed sensor shows Nernstian slope of 20.32 ± 1.18 mV decade− 1 over the working concentration range of 1.0 × 10− 6 − 1.0 × 10− 1 mol L− 1 of Al (III) ion with a detection limit of 3.3 × 10− 7 mol L− 1. The sensor exhibited a stable potential response in the pH range from 4.0 to 6.0 and a fast response time of 8 s. The prepared sensor indicated a very good selectivity to Al (III) over a variety of cations. The sensor could be easily employed for determination of Al (III) ions in pharmaceutical products, soft drink and biological fluids of kidney failure and Alzheimer disease patients. The reaction mechanism between pCL-MA and Al (III) was confirmed by FT-IR spectroscopic analysis, SEM and EDX.

The online version contains supplementary material available at 10.1038/s41598-025-32308-z.