Synthesis and characterization of biocompatible ZnO nanoparticles

ZnO nanoparticles are among the most promising emerging fluorescent labels for cellular imaging. However, there are only a few reports on the successful application of ZnO nanoparticles in biolabeling so far. The major problem of ZnO nanoparticles arises from their poor stability in water. In this work, two new facile synthesis methods were developed for fabricating water-stable ZnO nanoparticles, which have blue and yellow fluorescence and are expected to be of use for labeling different cellular structures simultaneously. Transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectrometry (FT-IR), UV-vis, and fluorescence spectrophotometry (PL) were employed to investigate the structures and properties of ZnO nanoparticles. The mechanisms for the formation of the ZnO nanoparticles of both samples are analyzed. Furthermore, hemolysis assay was performed to evaluate the biocompatibility of these ZnO nanoparticlesin vitro. The biocompatibility of the ZnO nanoparticles, even at very high doses, ensures their potential in biomedical applications.