RESUMO
Membrane permeation-controlled transdermal delivery devices for the controlled delivery of nifedipine were developed using collagen (which was extracted from calf fetus skin) and chitosan membranes as rate-controlling membrane. To increase the stability of nifedipine in the systems, alginate gel was used as drug reservoir. Transdermal devices were fabricated by adhesive sealing techniques. In vitro drug release studies were carried out using modified Franz diffusion cells. Drug release was found to depend on the type of membrane used to control the drug delivery, suggesting that drug delivery is efficiently controlled by the rate-controlling membranes.
Assuntos
Materiais Biocompatíveis , Biopolímeros , Sistemas de Liberação de Medicamentos , Nifedipino/administração & dosagem , Adesivos , Animais , Bovinos , Quitina/análogos & derivados , Quitosana , Colágeno , Técnicas In Vitro , Teste de Materiais , Membranas Artificiais , Nifedipino/farmacocinética , Permeabilidade , Coelhos , Pele/metabolismoRESUMO
Membrane permeation-controlled transdermal drug delivery systems were prepared using the natural polymer, chitosan. An adhesive sealing technique was used to construct the devices. Propranolol hydrochloride was selected as the model drug for the present study. Chitosan membranes with different permeability to propranolol hydrochloride obtained by controlled cross-linking with glutaraldehyde were used to regulate the drug release in the devices. Chitosan gel was used as the drug reservoir. The ability of these devices to deliver the drug while supported on rabbit pinna skin was tested by conducting in vitro studies in modified Franz diffusion cells. The drug release profiles showed that the drug delivery is completely controlled by the devices. The rate of drug release was found to be dependent on the type of membrane used.
Assuntos
Administração Cutânea , Quitina/análogos & derivados , Sistemas de Liberação de Medicamentos/normas , Propranolol/administração & dosagem , Animais , Anticolesterolemiantes , Quitina/química , Quitosana , Difusão , Sistemas de Liberação de Medicamentos/métodos , Epiderme , Estudos de Avaliação como Assunto , Hemostáticos , Membranas Artificiais , Permeabilidade , Coelhos , Pele/efeitos dos fármacos , Pele/ultraestruturaRESUMO
Chitosan membranes of 20 microns thickness were prepared by a solvent evaporation technique and crosslinked with different concentrations of glutaraldehyde to obtain membranes of various degrees of crosslinking. These membranes were characterized by thermogravimetric (TG) analysis, differential scanning calorimetry (DSC) and tensile strength studies. The effect of crosslinking on the permeability of membranes to propranolol hydrochloride was evaluated by permeation studies conducted in static glass diffusion cells. A decrease in the thermal stability of chitosan membranes due to crosslinking was observed. The tensile strength of the membranes was improved by crosslinking. The introduction of crosslink points within the membrane reduced its permeability to propranolol hydrochloride as evidenced by decreased permeability and diffusion coefficients. Permeability studies revealed the operation of a pore mechanism in the transport of hydrophilic agents such as propranolol hydrochloride through chitosan and crosslinked chitosan membranes.