Dityrosine (DY), which is fluorescent and biocompatible, has multiple functional groups, including two amine and two carboxylic acid groups. By conjugating PEG arms to DY, we successfully synthesized a star-shaped 4-arm PEG with two carboxylic acid and two amine groups at its four ends. Two different kinds of molecules could be further linked to this 4-arm PEG.The chemical structures and molecular weights of the intermediate 2-arm PEG and 4-arm PEG were determined by 1H NMR spectroscopy and matrix assisted laser desorption ionization-time of flight-mass spectrometry (MALDI-TOF-MS).
Bibliographical noteFunding Information:
This study was supported by the Advanced Biomass R&D Center (ABC) of Korea (Grant No. 2010-0029734 ) funded by the Ministry of Education, Science and Technology .
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)