5560
To the best of our knowledge , this is the first report on paper - based devices for automating the sequential multistep procedures of a sandwich - type enzyme - linked immunosorbent assay ( ELISA ) that require only a single - step application of the sample solution .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
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