Comparing Cytotoxicity of ZnO Nanoparticles in Exposure to Serum/Serum-free Cell Culture Medium

摘要

The aim of this study is to evaluate the influence of serum [fetal bovine serum (FBS)] in cell culture medium on the nano and micro-sized ZnO toxicity to human lung epithelial cells (A549). Particles agglomeration and sedimentation state in medium were respectively measured by Zetasizer and UV-vis spectrometer. Methyl thiazolyl tetrazolium (MTT) and interleukin 8 (IL-8) analysis were selected for cytotoxicity assays. We found ZnO particles with a smaller primary size increased to a relative smaller secondary size in both serum/serum-free Dulbecco's modified Eagle's medium (DMEM), and caused the size-dependent cytotoxicity effect on ZnO nanoparticles. However, negative charges of serum caused the zeta potential of ZnO slightly decreased to -8 ～ -10 mV in DMEM, which resulted in smaller hydrodynamic size and much slower sedimentation than in serum free medium, leading to similarly lower toxicity.