15815
Based on the properties of the inverted motility geometry , the total size of these nanofluidic networks was limited by MT surface density , molecular motor energy source ( ATP ) , and total amount and physical properties of lipid source material .
 ATP
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 ATP