ZnO-Salen NPs employed as chemosensor for detection of Al 3+ and K + in aqueous medium, developing human cell images

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 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+) = 6.61x103 and β2(K+) = 3.71x103 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.