29802
Among the formulations investigated , poly ( lactic - co - glycolic acid ) - poly ( ethylene glycol ) - poly ( lactic - co - glycolic acid ) triblock copolymer systems provided the longest sustained drug delivery , probably due to their rigid gel structures and / or polymer - to - cidofovir interactions .
 Chemical: poly ( lactic - co - glycolic acid ); Chemical: poly ( ethylene glycol ); Chemical: poly ( lactic - co - glycolic acid ); Chemical: cidofovir
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: poly ( lactic - co - glycolic acid ); Chemical: poly ( ethylene glycol ); Chemical: poly ( lactic - co - glycolic acid ); Chemical: cidofovir