| 초록 |
A fluorescent and star-shaped 4-arm PEG was synthesized by the conjugation of 4 PEG molecules to dityrosine. When the PEG with M.W. 550 was conjugated to dityrosine as the first 2 arms, the 4-arm PEG was readily prepared with all the tested PEG molecules. When the PEG with M.W. 1000 was used as the first 2 PEG arms, the 4-arm PEG could be prepared with the PEG molecule with M.W. 550 only. When the PEG with M.W. 2000 or 5000 was conjugated to dityrosine as the first 2 arms, the 4-arm PEG could not be prepared with any of the tested PEG molecules. |
