16189
We have prepared and characterized a new set of highly fluorescent gold nanoclusters ( AuNCs ) using one - step aqueous reduction of a gold precursor in the presence of bidentate ligands made of lipoic acid anchoring groups , appended with either a poly ( ethylene glycol ) short chain or a zwitterion group .
 Chemical: lipoic acid; Chemical: poly ( ethylene glycol )
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: lipoic acid; Chemical: poly ( ethylene glycol )