A PLGA 15:85 polymer made of 15% PLA and 85 % PGA degrades very fast. One...

A PLGA 15:85 polymer made of 15% PLA and 85 % PGA degrades very fast. One of your colleagues suggests tripling the amount of the more hydrophobic PLA in the copolymer to slow down the degradation. Do you agree with him? Why?

Expert Solution

The composition of polymer plays a very important role in its degradation kinetics. It can either accelerate or decline the pace of degradation.The research studies have reported that the increase in glycolic acid concentration in PLGA(PLA/PGA) exhibits faster degradation due to elevated hydrophilicity.The order of degradation rate depending upon the glycolic acid content can be depicted as :PLGA 65:35> 75:25> 85:15. The amount of glycolic acid is thus a critical parameter helpful in tuning of the polymer system related to drug release and polymer degradation.

The monomeric ratio of lactic : glycolic acid plays an important role in degradation mechanism of PLGA.For instance PLGA 50:50 degrades at a faster rate as compared with PLGA 85:15 due to the higher hydrophobic lactide content of the latter

queen_honey_blossom answered 2 years ago

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