title: Development and Characterization of a Microemulsion System Containing Amphotericin B with Potential Ocular Applications.
abstract: BACKGROUND
  Amphotericin B eye drops are widely used in the treatment of ocular infections. However, amphotericin's toxicity leads to low patient compliance and aggravation of symptoms. This work describes the development of a microemulsion system containing amphotericin B, aiming for its use in ocular applications.
  
  
  METHODS
  The microemulsion was developed by the titration technique. The physicochemical characteristics were determined with both loaded and unloaded amphotericin B-microemulsion. The nanostructures were analyzed by polarized light microscopy. The microdilution method was used to establish the minimum inhibitory concentration against fungal strains, and, therefore, evaluate the microemulsion activity. Additionally, in order to evaluate the microemulsion toxicity an in vitro toxicity assay against red blood cells was performed.
  
  
  RESULTS
  The performed studies showed that the presence of amphotericin B loaded into the system did not induce serious changes in the physicochemical properties of the microemulsion when compared to the unloaded system. The spectrophotometric studies depicted amphotericin B-self-associated species, which allow predicting its behavior in vitro. The high pressure liquid chromatography results revealed high drug content entrapment in the microemulsion droplet. Finally, the amphotericin B-microemulsion in vitro susceptibility test showed high activity against Candida strains and a low toxicity profile against red blood cells when compared to Fungizone®.
  
  
  CONCLUSIONS
  The physicochemical characterization of the microemulsion demonstrated that its characteristics are compatible with the topical ocular route, making it eligible for consideration as a new and interesting amphotericin B-deliverydosage form to be used as eye drop formulation.
authors.forename: Walteçá Louis Lima
authors.initials: WL
authors.lastname: da Silveira
authors.forename: Bolivar P G L
authors.initials: BP
authors.lastname: Damasceno
authors.forename: Laura F
authors.initials: LF
authors.lastname: Ferreira
authors.forename: Izabel L S
authors.initials: IL
authors.lastname: Ribeiro
authors.forename: Karolyne S
authors.initials: KS
authors.lastname: Silva
authors.forename: André Leandro
authors.initials: AL
authors.lastname: Silva
authors.forename: Maria José Mendes
authors.initials: MJ
authors.lastname: Giannini
authors.forename: Arnóbio Antônio
authors.initials: AA
authors.lastname: da Silva-Júnior
authors.forename: Anselmo Gomes
authors.initials: AG
authors.lastname: de Oliveira
authors.affiliation: Department of Pharmacy, Universidade Federal do Rio Grande do Norte, Rua Praia de Areia Branca, 8948, CEP 59094-450, Natal, RN, Brazil. socrates@ufrnet.br.
authors.forename: E Sócrates Tabosa
authors.initials: ES
authors.lastname: do Egito
mesh_terms: D000666:Amphotericin B / Q000008:administration & dosage* / Q000494:pharmacology*; D000935:Antifungal Agents / Q000008:administration & dosage* / Q000494:pharmacology; D004337:Drug Carriers / Q000008:administration & dosage* / Q000009:adverse effects / Q000737:chemistry; D004655:Emulsions / Q000008:administration & dosage* / Q000009:adverse effects / Q000737:chemistry*; D004912:Erythrocytes / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D049329:Nanostructures / Q000008:administration & dosage / Q000009:adverse effects / Q000737:chemistry; D009883:Ophthalmic Solutions / Q000008:administration & dosage* / Q000009:adverse effects / Q000737:chemistry; D010316:Particle Size
chemical_list: D000935:Antifungal Agents; D004337:Drug Carriers; D004655:Emulsions; D009883:Ophthalmic Solutions; D000666:Amphotericin B