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Then , the chemical profile was determined using a C18 reversed column chromatography in a gradient solvent system with 10 - 40 % acetonitrile in 0 . 1 % formic acid , for 60 min .
 Chemical: acetonitrile; Chemical: formic acid
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: acetonitrile; Chemical: formic acid