Molecular dynamics of poly(lactide-co-glycolide) controlled pharmaceuticalrelease polymers: Preliminary solid state NMR

Variable temperature C-13 cross polarization magic angle spinning (CP-MAS) and H-1 T-1 and T-1 rho studies have been initiated on microspheres of the poly(lactide-co-glycolide) (PLGA) materials widely studied as controlled re lease pharmaceutical formulation excipients. Temperature dependence of line shape and T-1 rho suggest that around the broad glass transition at about 5 0 degrees C slow polymer backbone motions (on the 10 to 100 mu s time scale ) become significant; modelling of these is in progress.