By Yixin Ren
The biodegradable and biocompatible co-polymer poly(lactide-co-glycolide) (PLGA) comprises various ratios of its monomers: lactide and glycolide (L&G), and used extensively in biomedical applications such as drug delivery and tissue engineering applications. Microscopic properties of the PLGA materials, such as L/G ratio, molecular weight, and end-capping have known to have great impact on their physical properties. However, accurately determine the L/G ratio, molecular weight and end group analysis are still a challenge. Nuclear magnetic resonance (NMR) spectroscopy has historically been employed for structure elucidation; however recent advances in instrumentation and in data processing have prompted renewed interest in its quantitative applications. Quantitative NMR (qNMR) possesses numerous advantages, not least of them being its universality, and molar proportionality of response. Herein, we assess the qNMR analysis for number average molecular weight and L/G ratio determination, and end group analysis, which afforded the results in accordance with the size exclusion chromatography (SEC) and matrix-assisted laser desorption-ionization time of flight spectroscopy (MALDI-ToF).