11977
In vitro insulin release studies were performed in phosphate buffer pH 7 . 4 and also in HCl pH 2 with and without trypsin .
 Chemical: phosphate; Chemical: HCl
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: phosphate; Chemical: HCl