点击放大环状聚乙二醇-聚乙二醇臂-NHS活性酯（n=64）388-crown-129-PEG64-CH2COONHS Ester; N-hydroxysuccinimide ester-terminated PEG arm on a cyclic poly(ethylene glycol) scaffold (arm n=64)
点击放大四臂-聚乙二醇-NHS活性酯（n=64）4-Arm-PEG64-CH2CH2COONHS Ester; 4-Arm N-hydroxysuccinimide ester-functionalized discrete poly(ethylene glycol) (PEG arm n=64)
