The application of microspheres from the copolymers of lactide and epsilon-caprolactone to the controlled release of steroids.
The microspheres made of the copolymers of lactide and epsilon-caprolactone were used for the controlled release of progesterone and beta-estradiol. The copolymers contained 83-94% of l or d,l-lactide. The influence of the microstructure of lactidyl blocks in the copolymer chains on the drug release rate was studied. More uniform release rate was observed in the case of the copolymer derived from d,l-lactide as composed to l-lactide. For the copolymer containing 83-94% of d,l-lactide units the progesterone and beta-estradiol release rate in vitro was found to be practically constant within over 40 days. The in vivo studies performed on rats revealed that the period of constant release rate of beta-estradiol can be prolonged to about 70 days. The microspheres made of the applied poly-(d,l-lactide-co-epsilon-caprolactone) are the convenient system for long time release of steroids.
Buntner
B
B
Department of Pathophysiology, Silesian University, School of Medicine, 41-800, Zabrze, Poland.
Nowak
M
M
Kasperczyk
J
J
Ryba
M
M
Grieb
P
P
Walski
M
M
Dobrzyñski
P
P
Bero
M
M
D000818:Animals; D002626:Chemistry, Pharmaceutical; D003692:Delayed-Action Preparations; D004958:Estradiol / Q000008:administration & dosage* / Q000737:chemistry* / Q000493:pharmacokinetics; D008297:Male; D008863:Microspheres; D011091:Polyesters / Q000008:administration & dosage / Q000737:chemistry* / Q000493:pharmacokinetics; D011374:Progesterone / Q000008:administration & dosage* / Q000737:chemistry* / Q000493:pharmacokinetics; D051381:Rats; D017208:Rats, Wistar; D013237:Stereoisomerism
D003692:Delayed-Action Preparations; D011091:Polyesters; D011374:Progesterone; D004958:Estradiol; C062968:lactide-caprolactone copolymer