12645
The optimal nanoparticle formulation using 0 . 25 % ( w / v ) of emulsifying agent ( Polyvinyl - alcohol , PVA ) and 5 min of sonication was then characterized .
 Chemical: Polyvinyl - alcohol; Chemical: PVA
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: Polyvinyl - alcohol; Chemical: PVA