21985
After intravenous and intradermal administration , IFN alpha was rapidly cleared from the serum , t1 / 2 0 . 75h , k 0 . 9271h ( - 1 ) and t1 / 2 1 . 28h , k 0 . 5421h ( - 1 ) , respectively , whereas after topical application , IFN alpha levels remained below 100U / mL .
 None
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 None