25939
Due to their physical properties , superparamagnetic iron oxide nanoparticles ( SPIONs ) and plasmonic gold nanoparticles ( Au - NPs ) are extensively studied as a part of diagnostic and therapeutic strategies in cancer treatments .
 Chemical: iron oxide; Chemical: Au
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: iron oxide, Au 
Answer:
 Chemical: iron oxide; Chemical: Au