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Thus not only can these materials catalyze the decomposition reaction of H ( 2 ) O ( 2 ) into water and oxygen , but they can also catalyze the oxidation of o - phenylenediamine ( OPD ) , a common substrate for peroxidases , by H ( 2 ) O ( 2 ) .
 H ( 2 ) O ( 2 ), oxygen, o - phenylenediamine, OPD, H ( 2 ) O ( 2 )
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 H ( 2 ) O ( 2 ), oxygen, o - phenylenediamine, OPD, H ( 2 ) O ( 2 )