关键词: sub>, 团聚体, 无细胞体系, 自由基

Abstract: Abstract:Objective To detect the characterization and non cellular ROS activities of nano silica particle and provide references for predicting its toxicity in vivo and in vitro.Methods Transmission electron microscope(TEM) was used to observe particle size,shape and dispersibility of the two silica particles;the size and agglomeration state of particles in water,saline,10% Tween 80,RPMI 1640 and RPMI1640 containing 1% FBS were measured in 0,24,48 and 72 h after 30 s-sonication by Zeta Potential Analyzer;non cellular ROS activity was detected using DCFH-DA regents.Results TEM image showed nano silica particles were round and dispersed evenly;the average sizes of the two silica particles were (43.0±4.2) and (68.0±5.7) nm.Silica particles had different sizes in water,saline,10% Tween 80,RPMI 1640 and RPMI1 640 containing 1% FBS,among them,two particles had smallest sizes in saline,which were 74.0 and 96.7 nm,respectively.And at 0,24,48 and 72 h after 30 s-sonication,Si-43 nm and Si-68 nm did not form agglomeration in water but formed similar agglomeration in RPMI 1640 cell culture medium containing 1% FBS.The two nanoparticles hardly caused any increasing of ROS between 30-100 μg mass range in cell free system,just equivalent 2.5 μmol•L^-1 H₂O₂. Conclusion Nano silica particles could form agglomerations in cell culture medium and almost have no ROS activities in non cellular system.

Key words: agglomeration, non cellular, free radicals