Effect of Zinc Oxide and Titanium Dioxide Nanoparticles on Supported Lipid Bilayers

Abstract

Nanoparticles (NP) are broadly exploited in biomedical sciences in order to develop various methods of targeted drug delivery, novel biosensors and new therapeutic pathways. However, relatively little is known in the negotiation of NPs with complex biological environments. NP interaction with cell membranes can damage the cell membrane and cause toxicity; therefore, examining interactions between NPs and cell membranes is crucial to understanding NP toxicity mechanisms and the development of safe and non-toxic NP-based commercial and therapeutic applications. To gain a physical understanding of NP-membrane interactions, we used a simplified system built of well-defined synthetic lipid bilayers and NP. The interaction of nanoparticles (NPs) with supported lipid bilayers (SLB) can lead to structural modification of the SLB and affect the structure and dynamic of lipids. In this work TiO 2 and ZnO nanoparticles were chosen because of wide applications and usage in industry of papers, inks, medicines, food products, cosmetics, toothpastes and skin care products and among others. Therefore, a better understanding of the interactions between NP and lipid membrane may help to better clarify the potential risk of NPs. The interaction between ZnO and TiO 2 NPs and lipid membranes was studied by using scanning supercritical angle fluorescence microscopy. The biological response to elucidated changes in lipid membrane structure/characteristics under ZnO or TiO 2 NP influence was tested by fluorescence correlation spectroscopy. It was found the significant reduction of lipids diffusion mobility, which can be explained as a result of lipid-ZnO aggregates binding, depending on ZnO concentration. The TiO 2 has a little effect on lipids diffusion mobility.