1975
From concentration - dependent studies , we found that 5 mu M of this compound induced a drastic decrease in viable cells with a concomitant accumulation in intracellular copper resulted from complexation with DEDTC , measured by atomic absorption spectroscopy .
 Chemical: copper; Chemical: DEDTC
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: copper; Chemical: DEDTC