7207
This was demonstrated with the highly cross - reactive elapid Egyptian snake venoms Naja haje ( Nh ) , Naja nigricollis ( Nn ) and Walterinnesia aegyptia ( Wa ) , and used for the differentiation among the three species in a simple ELISA - based assay .
 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