15748
Two ligands , a 4 - pyridyl and a bis ( 2 - hydroxyethyl ) derivative of lipoic acid , were selected to investigate the feasibility for producing molecularly imprinted self - assembled layers on gold for T4 .
 Chemical: 4 - pyridyl; Chemical: bis ( 2 - hydroxyethyl ); Chemical: lipoic acid
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: 4 - pyridyl, bis ( 2 - hydroxyethyl ), lipoic acid 
Answer:
 Chemical: 4 - pyridyl; Chemical: bis ( 2 - hydroxyethyl ); Chemical: lipoic acid