MRI investigation of hydration and heterogeneous degradation of aliphatic polyesters derived from lactic and glycolic acids: a controlled drug delivery device.
Magnetic Resonance Imaging experiments have been used to investigate the degradation of drug-loaded poly(glycolic lactic acid) (PGLA) 50:50 cylinders. Spatial variation in the rate of degradation throughout the polymer cross-section has been observed non-invasively using quantitative imaging of penetrant concentration, T(2) and self-diffusion coefficient. This spatial variation in the rate of degradation was attributed to the quicker degradation in the inner region of the sample due to autocatalysis by carboxyl end groups generated upon ester bond cleavage.
Djemai
A
A
Department of Chemical Engineering, University of Cambridge, Pembroke Street, CB2 3RA, Cambridge, UK.
Gladden
L F
LF
Booth
J
J
Kittlety
R S
RS
Gellert
P R
PR
D002384:Catalysis; D004337:Drug Carriers / Q000737:chemistry; D016503:Drug Delivery Systems; D004355:Drug Stability; D006016:Glycolates / Q000737:chemistry; D019344:Lactic Acid / Q000737:chemistry; D008279:Magnetic Resonance Imaging / Q000379:methods*; D011091:Polyesters / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
D004337:Drug Carriers; D006016:Glycolates; D011091:Polyesters; D014867:Water; C031149:glycolic acid; D019344:Lactic Acid