# ZnO-Salen NPs Employed as Chemosensor for Detection of Al3+ and K+ in Aqueous Medium, Developing Human Cell Images

## TL;DR

Researchers developed a chemosensor using ZnO-salen nanoparticles to detect Al3+ and K+ ions in water and human cells, with high selectivity and low toxicity.

## Contribution

A novel ZnO-salen nanoparticle system is introduced for selective detection of Al3+ and K+ ions in aqueous and cellular environments.

## Key findings

- ZnO-salen selectively detects Al3+ with a fluorescence enhancement in aqueous medium.
- The presence of K+ further intensifies fluorescence in the [ZnO-salen-Al3+] system.
- The system achieved detection limits of 36.51 µM for Al3+ and 17.39 µM for K+ with high cell viability.

## Abstract

ZnO nanoparticles (NPs) were prepared and characterized by different analytical methods and then they were used to decorate with N, N´-bis(salicylidene)ethylenediamine (salen) in order to perform as receptor for the metal ions in an aqueous medium. The results show that ZnO-salen selectively detects Al3+ ions in aqueous medium since the intensity of fluorescence has been enhanced significantly. However, the presence of K+ in the medium further intensified the fluorescence emission for the [ZnO-salen-Al3+] system. The above system has been applied to recognize Al3+ and K+ in cells by developing the cell images, for which, the fluorescence image is brightened if a human glioblastoma U251 cell contains [ZnO-salen-Al3+] + K+ ions, consisting of the fluorescence titration. The binding global constant for Al3+ and the subsequent recognition of K+ by ZnO-salen resulted in β2(Al3+) = 6.61 × 103 and β2(K+) = 3.71 × 103 with a detection limit of 36.51 µM for Al3+ and 17.39 µM for K+. In the cell toxicity analysis, the cell viability was over 85% for the ZnO-salen even in the concentration as high as 100 mM.

The online version contains supplementary material available at 10.1007/s10895-024-03913-4.