9616
The probe responds rapidly to pH fluctuations and has such absorption characteristics that the color changes from the colorless or a nearly colorless state to a colored state with increasing acidity , so PEI - capped Ag nanoclusters could be used as a color indicator for colorimetric pH detection .
 Chemical: PEI; Chemical: Ag
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: PEI; Chemical: Ag