19087
Surface - enhanced Raman scattering ( SERS ) spectra of 4 - mercaptobenzoic acid ( 4 - MBA ) have been investigated on the surface of Cu2O nanospheres .
 Chemical: 4 - mercaptobenzoic acid; Chemical: 4 - MBA; Chemical: Cu2O
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: 4 - mercaptobenzoic acid; Chemical: 4 - MBA; Chemical: Cu2O