18884
A wide range of materials , including liposomes , microspheres , polymers and recently , carbon nanotubes ( CNTs ) , have been investigated for delivering anticancer drugs on the purpose of reducing the number of necessary administrations , providing more localized and better use of the active agents , and increasing patient compliance .
 Chemical: carbon
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