1482
Our results also suggest that the generation of hydroxyl radicals and reactive oxygen species ( ROS ) - mediated damage to the surface - adsorbed biomolecules could be the two major reasons for the cytotoxicity of TiO ( 2 ) nanoparticles after photoactivation .
 Chemical: hydroxyl; Chemical: oxygen; Chemical: TiO ( 2 )
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: hydroxyl; Chemical: oxygen; Chemical: TiO ( 2 )