29678
The resultant hollow nanogels , though slightly swollen , satisfactorily retain the structural integrity while the medium pH being adjusted to 7 . 4 .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities:  
Answer:
 None