9999
Because of colloidal stability concerns and toxicity issues the potential in vivo application of these so - called non - viral systems , in particular cationic lipids , was met with considerable skepticism .
 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