PEG-PLA purification

01 January 1970 1 4K Report

I am working on the PEG-PLA copolymer. Before purification, I have a certain size (about 15 000 Da of PLA). But after purification of this polymer in water (to then lyophilize and obtain a white powder), I obtain in NMR a PLA of 7000 Da. Do you think that it is possible that during the precipitation in water there is hydrolysis of PLA? How to avoid it ?

Abdelkader BOUAZIZ

Dear Louise Van Gheluwe, PLA hydrolytic degradation is the first cause assumed for its degradation. I suggest to precipitate in solution containing carbodiimide stabilizer. My Regards

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