Abstract
A novel amphiphilic graft copolymer composed of poly(γ-glutamic acid) (γ-PGA) as a hydrophilic backbone and dodecylamine (DOA) as a hydrophobic side chain (γ-PGA-DOA) was successfully synthesized by employing 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) as the coupling reagent. The grafting degree was stoichiometrically controlled by adjusting the feeding amounts of DOA and EDC in the reaction system. γ-PGA-DOA, with a grafting degree of 55%, self-assembled via hydrophobic interactions and formed microparticles (MPs; diameter of 13±3 μm) in an aqueous solution. These MPs possessed functional carboxylic groups and could be further modified with compounds such as drugs, proteins and peptides, and thus have great potential as vaccine carriers.
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Acknowledgements
This work was supported by the Japan Society for the Promotion of Science (JSPS), Japanese-German Graduate Externship, and Deutsche Forschungsmeinschaft within the project ‘Selectivity in Bio- and Chemoselectivity’. This work was partially supported by a Grant-in-Aid for Scientific Research (S) from the Ministry of Education, Culture, Sports, Science and Technology (23225004).
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Shima, F., Schulte, B., Keul, H. et al. Preparation of microparticles composed of amphiphilic poly(γ-glutamic acid) through hydrophobic interactions. Polym J 46, 184–188 (2014). https://doi.org/10.1038/pj.2013.74
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DOI: https://doi.org/10.1038/pj.2013.74
