ABSTRACT
ABSTRACT Purpose: To determine the release profile of moxifloxacin encapsulated in liposomes in the aqueous humor as a controlled release system for intracameral application. Methods: Liposomes containing moxifloxacin were obtained using the lipid film hydration method and were characterized by particle size and encapsulation efficiency. Female rabbits were used for the in vivo profile release study. Liposomes containing moxifloxacin was injected into the anterior chamber of the right eye of each animal. The rabbits were divided into five groups, and a sample of aqueous humor was collected 2, 4, 8, 24, and 48 h after administration of liposomes containing moxifloxacin administration. Moxifloxacin concentrations in the aqueous humor were analyzed using high-performance liquid chromatography. Results: The average size of the liposomes containing moxifloxacin was 60.5 ± 0.72 nm with a particle size distribution of 0.307. The encapsulation efficiency of moxifloxacin in liposomes was 92.24 ± 0.24%. The results of an in vivo release study of liposomes containing moxifloxacin, showed that the maximum moxifloxacin concentration was achieved within the first 2 h after administration (5.27 ± 1.09 mg/mL) and was followed by a decrease in intracameral concentration (0.35 ± 0.05 mg/mL) until the 24 h mark. Conclusions: The in vivo experiments resulted in liposomes containing moxifloxacin that were homogenous in size and exhibited high drug encapsulation efficiency. The results indicate that liposomes containing moxifloxacin offers a satisfactory aqueous humor release profile after intracameral application.
RESUMO Objetivo: Determinar o perfil de liberação, no humor aquoso, de moxifloxacino encapsulado em lipossomas como um sistema de liberação controlada para aplicação intracameral. Métodos: Lipossomas contendo moxifloxacino foram obtidos através do método de hidratação do filme lipídico e caracterizados por tamanho da partícula e eficiência de encapsulação. Utilizaram-se coelhos fêmeas foram para o estudo do perfil de liberação in vivo. Lipossomas contendo moxifloxacino foram injetados na câmara anterior do olho direito de cada animal. Os coelhos foram divididos em cinco grupos, e uma amostra de humor aquoso foi coletada 2, 4, 8, 24 e 48 h após a administração de lipossomas contendo moxifloxacino. As concentrações de moxifloxacino no humor aquoso foram analisadas usando cromatografia líquida de alta eficiência. Resultados: O tamanho médio dos lipossomas contendo moxifloxacino foi de 60,5 ± 0,72 nm com uma distribuição de tamanho de partícula de 0,307. A eficiência de encapsulação de moxifloxacino nos lipossomas foi de 92,24 ± 0,24. Os resultados de um estudo de liberação in vivo de lipossomas contendo moxifloxacino, mostraram que a concentração máxima de moxifloxacino foi atingida dentro das primeiras 2 h após sua administração (5,27 ± 1,09 mg/mL) e foi seguida de um decréscimo na concentração intracameral (0,35 ± 0,05 mg/mL) até a marca de 24 h. Conclusão: Os experimentos in vivo resultaram em lipossomas contendo moxifloxacino que eram homogêneos em tamanho e exibiam alta eficiência de encapsulação do fármaco. Os resultados indicam que lipossomas contendo moxifloxacino oferecem um perfil de liberação de humor aquoso satisfatório após a aplicação intracameral.
Subject(s)
Animals , Female , Rats , Aqueous Humor , Drug Delivery Systems/methods , Moxifloxacin/administration & dosage , Anti-Bacterial Agents/administration & dosage , Biological Availability , Chromatography, High Pressure Liquid , Models, Animal , Injections, Intraocular , Moxifloxacin/analysis , Moxifloxacin/pharmacokinetics , Liposomes , Anti-Bacterial Agents/analysis , Anti-Bacterial Agents/pharmacokineticsABSTRACT
An increase in dentin roughness, associated with surface composition, contributes to bacterial adherence in recontaminations. Surface roughness is also important for micromechanical interlocking of dental materials to dentin, and understanding the characteristics of the surface is essential to obtain the adhesion of root canal sealers that have different physico-chemical characteristics. OBJECTIVES: To evaluate the effects of sodium hypochlorite (NaOCl), ethylenediaminetetraacetic (EDTA), etidronic (HEBP), and citric acid (CA) associated with different irrigation regimens on root dentin roughness. MATERIAL AND METHODS: Forty-five root halves of anterior teeth were used. The root parts were sectioned in thirds, embedded in acrylic resin and polished to a standard surface roughness. Initially, the samples of each third were randomly assigned into 3 groups and treated as follows: G1 - saline solution (control); G2 - 5% NaOCl+18% HEBP mixed in equal parts; and G3 - 2.5% NaOCl. After initial measuments, the G3 samples were distributed into subgroups G4, G5 and G6, which were subjected to 17% EDTA, 10% CA and 9% HEBP, respectively. Following the new measuments, these groups received a final flush with 2.5% NaOCl, producing G7, G8 and G9. The dentin surface roughness (Ra) was determined before and after treatments using a profilometer. The Wilcoxon test (α<0.05) was used to compare the values before and after treatments, and the Friedman test (α<0.05) to detect any differences among root thirds. RESULTS: (i) NaOCl did not affect the surface roughness; (ii) there was a significant increase in roughness after the use of chelating agents (P<0.01); and (iii) only the G3 group showed a difference in surface roughness between apical third and other thirds of the teeth (P<0.0043). CONCLUSION: Only the irrigation regimens that used chelating agents altered the roughness of root dentin. .