20985
The correlations ( r ( 2 ) ) between membrane and diffusion cell data from saturated and unsaturated concentrations were 0 . 38 , 0 . 47 and 0 . 56 for the Strat - M (TM) , certramide and IPM membranes , respectively .
 certramide, IPM
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 certramide, IPM