6680
Taken together , we present , to the best of our knowledge , the first example of bioresorbable physical hydrogel based on PVA with engineered opportunities in substrate - mediated enzymatic activity and envisioned utility in surface - mediated drug delivery and tissue engineering .
 Chemical: PVA
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: PVA