14335
The PLGA and PLGA / Ag nanocomposite surfaces were treated with oxygen plasma .
 Chemical: PLGA; Chemical: PLGA; Chemical: Ag; Chemical: oxygen
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: PLGA, PLGA, Ag, oxygen 
Answer:
 Chemical: PLGA; Chemical: PLGA; Chemical: Ag; Chemical: oxygen