26936
No significant penetration enhancing effect for ibuprofen has been observed , but with increasing spilanthol concentration ( from 0 up to 1w / V % ) , the permeability of caffeine increased , resulting in an enhancing ratio ( ER ) of 4 . 60 .
 Chemical: ibuprofen; Chemical: spilanthol; Chemical: caffeine
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: ibuprofen; Chemical: spilanthol; Chemical: caffeine