info:eu-repo/semantics/article
Evaluation of pH-sensitive poly(2-hydroxyethyl methacrylate-co-2- (diisopropylamino)ethyl methacrylate) copolymers as drug delivery systems for potential applications in ophthalmic therapies ocular delivery of drugs
Registro en:
eXPRESS Polymer Letters
10.3144/expresspolymlett.2015.52
Autor
Faccia, Paula
Pardini, Francisco
Amalvy, Javier
Institución
Resumen
Smart polymers like pH sensitive systems can improve different pharmacological treatment. In this work the behavior of copolymers containing 2-hydroxyethyl methacrylate (HEMA) with different proportions of 2-(diisopropylamino)ethyl methacrylate (DPA) and different amounts of cross-linker agent, ethylene glycol dimethacrylate (EGDMA) are evaluated as pH- sensitive drug delivery system for potential application in ophthalmic therapies. A detailed characterization of the pH-responsive behavior was performed by swelling studies and scanning electron microscopy (SEM) analysis. Drug loading and release studies at different pH values were evaluated using Rhodamine 6G (Rh6G) as a model drug. The interaction between Rh6G and hydrogels was studied by FTIR spectroscopy and SEM. The results show that the presence of DPA in the copolymers confers pH-responsive properties to the polymer, as noted in swelling and SEM studies, when the pH decreases below 7.40 the swelling degree increases and a porous morphology is observed. The apparent pKa of copolymers was estimated between 6.80 and 7.17 depending on the composition. The amount of Rh6G loaded depends mainly on the medium pH and the interaction between the drug and the copolymers, observed by SEM and FTIR spectrum. The release of Rh6G of copolymers p(HEMA/DPA) show a normal Fickian or anomalous diffusion behavior at different pH values, depending on the HEMA/DPA ratio. Fil: Paula A. Faccia, Paula. UNLP (Universidad Nacional de La Plata). INIFTA (Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas). CONICET; Argentina Fil: Pardini, Francisco. CIDEPINT (Centro de Investigación y Desarrollo en Tecnología de Pinturas) CONICET/CICPBA; Argentina Fil: Amalvy, Javier. UNLP (Universidad Nacional de La Plata). INIFTA (Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas). CONICET. CIDEPINT (Centro de Investigación y Desarrollo en Tecnología de Pinturas) CONICET/CICPBA. UTN (Universidad Tecnológica Nacional). CITEMA (Centro de Investigación y Desarrollo en Ciencia y Tecnología de Materiales); Argentina Peer Reviewed