The initial release of cisplatin from poly(lactide-co-glycolide) microspheres.
PLGA microspheres loaded with cisplatin were produced using a single emulsion method. A semi-empirical model, with bi-exponential terms, was found to give a better fit to the drug release profiles compared to a mono-exponential model. This model suggests that there are two separate fractions of drug present in the depot. A fraction of the drug is located near/at the surface of the depot, and is readily released during immersion in buffer. A second fraction of drug is entrapped deeper within the depot and is subsequently released. It was also found that the initial release of cisplatin from PLGA microsphere is highly diffusion-controlled and the classical Higuchi model provides a good fit. From studies of water diffusion using PFG-NMR, results suggested that 50:50 PLGA microsphere was most susceptible to swelling and this might have promoted the faster initial drug release. Results from NMR cryoporometry also indicated that the developed PLGA microspheres could have "ink-bottle" pores.
Lee
Yan Sim
YS
Department of Chemical Engineering, University of Bath, Bath BA2 7AY, United Kingdom.
Lowe
John P
JP
Gilby
Ed
E
Perera
Semali
S
Rigby
Sean P
SP
D002945:Cisplatin / Q000737:chemistry / Q000378:metabolism*; D004337:Drug Carriers / Q000737:chemistry / Q000378:metabolism*; D019344:Lactic Acid / Q000737:chemistry / Q000378:metabolism*; D008863:Microspheres; D011100:Polyglycolic Acid / Q000737:chemistry / Q000378:metabolism*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer
D004337:Drug Carriers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D002945:Cisplatin