11519
As compared with loose PEG conformation , dense PEG conformation is more efficient to maintain the bioactivity , increase the plasma half - life , and decrease the proteolytic sensitivity and immunogenicity of the PEGylated SAK .
 Chemical: PEG; Chemical: PEG
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: PEG; Chemical: PEG