1486
The results confirmed that surface coating of TiO ( 2 ) nanoparticles could reduce such toxicity after photoactivation , by hindering adsorption of biomolecules and generation of hydroxyl radical ( . OH ) during photoactivation .
 Chemical: TiO ( 2 ); Chemical: hydroxyl; Chemical: . OH
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: TiO ( 2 ); Chemical: hydroxyl; Chemical: . OH