14821
Binding studies could not be conducted with Au ( III ) , Al ( III ) , Zn ( II ) , Cu ( II ) , and Ni ( II ) , as these precipitated both proteins .
 Au ( III ), Al ( III ), Zn ( II ), Cu ( II ), Ni ( II )
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 Au ( III ), Al ( III ), Zn ( II ), Cu ( II ), Ni ( II )