25553
Bioreducible alginate - poly ( ethylenimine ) nanogels as an antigen - delivery system robustly enhance vaccine - elicited humoral and cellular immune responses .
 Chemical: poly ( ethylenimine )
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 ( ethylenimine )