11361
In addition , the cellular association of liposome / PEI was examined by flow cytometry and confocal microscopy .
 Chemical: PEI
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: PEI 
Answer:
 Chemical: PEI