28617
A well - defined amphiphilic polypeptide , poly ( glutamic acid ) 22 - block - poly ( alanine ) 8 ( PGlu22 - b - PAla8 ) , which plays the roles of both soluble ( functional ) additive and insoluble ( structural ) matrix , is employed to mediate the mineralization of CaCO3 at the air / water interface .
 Chemical: poly ( glutamic acid ) 22 - block - poly ( alanine ) 8; Chemical: PGlu22 - b - PAla8; Chemical: CaCO3
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: poly ( glutamic acid ) 22 - block - poly ( alanine ) 8; Chemical: PGlu22 - b - PAla8; Chemical: CaCO3