Your browser doesn't support javascript.
loading
Drug release mechanisms of chemically cross-linked albumin microparticles: effect of the matrix erosion.
Sitta, Danielly L A; Guilherme, Marcos R; da Silva, Elisangela P; Valente, Artur J M; Muniz, Edvani C; Rubira, Adley F.
Afiliação
  • Sitta DLA; Department of Chemistry, State University of Maringá, Av. Colombo, 5790, CEP 87020-900, Maringá, Paraná, Brazil.
  • Guilherme MR; Department of Chemistry, State University of Maringá, Av. Colombo, 5790, CEP 87020-900, Maringá, Paraná, Brazil.
  • da Silva EP; Department of Chemistry, State University of Maringá, Av. Colombo, 5790, CEP 87020-900, Maringá, Paraná, Brazil.
  • Valente AJM; Department of Chemistry, University of Coimbra, Coimbra 3004 535, Portugal.
  • Muniz EC; Department of Chemistry, State University of Maringá, Av. Colombo, 5790, CEP 87020-900, Maringá, Paraná, Brazil.
  • Rubira AF; Department of Chemistry, State University of Maringá, Av. Colombo, 5790, CEP 87020-900, Maringá, Paraná, Brazil. Electronic address: afrubira@uem.br.
Colloids Surf B Biointerfaces ; 122: 404-413, 2014 Oct 01.
Article em En | MEDLINE | ID: mdl-25087021
Albumin (BSA) microparticles were developed as a biotechnological alternative for drug delivery. Vitamin B12 (Vit-B12) was used as a model drug. The microparticles were obtained from maleic anhydride-functionalized BSA and N',N'-dimethylacrylamide (DMAAm) in a W/O emulsion without and with PVA. The microparticles produced at 15min of stirring without PVA showed the best results in terms of size, homogeneity, and sphericity. In such a case, BSA played a role as a surface active agent, replacing PVA. For longer stirring times, BSA was unable to act as an emulsifier. These microparticles showed an uncommon release profile, consisting of a two-step release mechanism, at the pH range studied. Considering that a two-step release mechanism is occurring, the experimental data were adjusted by applying modified power law and Weibull equations in order to describe release mechanism n and release rate constant k, respectively. Each one of the release stages was related to a specific value of n and k. The second stage was driven by a super case II transport mechanism, as a result of diffusion, macromolecular relaxation, and erosion. A third model, described by Hixson-Crowell, confirmed the erosion mechanism. Vit-B12 diffusion kinetics in aqueous solutions (i.e., without the microparticles) follows a one-step process, being k dependent on the pH, confirming that the two-step release mechanism is a characteristic profile of the developed microparticles. The microparticles released only 2.70% of their initial drug load at pH 2, and 58.53% at pH 10.
Assuntos
Palavras-chave
Texto completo
Adicionar na Minha BVS
Imprimir
XML
PubMed Links
Buscar no Google

Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Soroalbumina Bovina / Microesferas Tipo de estudo: Prognostic_studies Idioma: En Revista: Colloids Surf B Biointerfaces Assunto da revista: QUIMICA Ano de publicação: 2014 Tipo de documento: Article País de afiliação: Brasil País de publicação: Holanda
Texto completo
Adicionar na Minha BVS
Imprimir
XML
PubMed Links
Buscar no Google

Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Soroalbumina Bovina / Microesferas Tipo de estudo: Prognostic_studies Idioma: En Revista: Colloids Surf B Biointerfaces Assunto da revista: QUIMICA Ano de publicação: 2014 Tipo de documento: Article País de afiliação: Brasil País de publicação: Holanda