6906
Single - walled carbon nanotubes ( SWNTs ) wrapped with different types of lipids and polyethylene glycol ( PEG ) - grafted lipids were simulated with lipid bilayers .
 Chemical: carbon; Chemical: polyethylene glycol; Chemical: PEG
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: carbon; Chemical: polyethylene glycol; Chemical: PEG