11936
Filtration centrifugation experiments demonstrated much higher aqueous PHMB concentrations than did the assays for biologically effective PHMB .
 Chemical: PHMB; Chemical: PHMB
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: PHMB, PHMB 
Answer:
 Chemical: PHMB; Chemical: PHMB