After an initial screening of ingredients and production methods, nanoemulsions for ocular administration of timolol containing the drug as maleate (TM) or as ion-pair with AOT (TM/AOT) were prepared. The physico-chemical characterization of nanoemulsions, regarding mean diameter, pH, zeta potential, osmolarity, viscosity and surface tension, underlined their feasibility to be instilled into the eyes. Single components and emulsions were tested ex vivo on rabbit corneas to evaluate corneal irritation, that was measured according to opacity test. A marked decrease in corneal opacity was observed using the drug formulated in nanoemulsions rather than in aqueous solutions. Drug permeation and accumulation studies were performed on excised rabbit corneas. An increase in drug permeation through and accumulation into the corneas were observed using TM-AOT compared to TM due to an increase of lipophilicity of the drug as ion-pair. The introduction of chitosan (a positive charged mucoadhesive polymer) into emulsions allowed to increase TM permeation probably due to the interaction of chitosan with corneal epithelial cells.

Development of O/W nanoemulsions for ophthalmic administration of timolol

GALLARATE, Marina;CHIRIO, Daniela;BUSSANO, ROSANNA;PEIRA, Elena;BATTAGLIA, Luigi Sebastiano;BARATTA, Francesca;TROTTA, Michele
2013-01-01

Abstract

After an initial screening of ingredients and production methods, nanoemulsions for ocular administration of timolol containing the drug as maleate (TM) or as ion-pair with AOT (TM/AOT) were prepared. The physico-chemical characterization of nanoemulsions, regarding mean diameter, pH, zeta potential, osmolarity, viscosity and surface tension, underlined their feasibility to be instilled into the eyes. Single components and emulsions were tested ex vivo on rabbit corneas to evaluate corneal irritation, that was measured according to opacity test. A marked decrease in corneal opacity was observed using the drug formulated in nanoemulsions rather than in aqueous solutions. Drug permeation and accumulation studies were performed on excised rabbit corneas. An increase in drug permeation through and accumulation into the corneas were observed using TM-AOT compared to TM due to an increase of lipophilicity of the drug as ion-pair. The introduction of chitosan (a positive charged mucoadhesive polymer) into emulsions allowed to increase TM permeation probably due to the interaction of chitosan with corneal epithelial cells.
2013
440
2
126
134
http://www.elsevier.com/locate/ijpharm
Timolol; Ion pair; Nanoemulsions; Ocular administration; Corneal irritation
Marina, Gallarate; Daniela, Chirio; Rosanna, Bussano; Elena, Peira; Luigi, Sebastiano Battaglia; Francesca, Baratta; Michele, Trotta
File in questo prodotto:
File Dimensione Formato  
timololo.pdf

Open Access dal 21/01/2014

Tipo di file: POSTPRINT (VERSIONE FINALE DELL’AUTORE)
Dimensione 485.08 kB
Formato Adobe PDF
485.08 kB Adobe PDF Visualizza/Apri
ophthalmic nanoemulsions.pdf

Accesso riservato

Descrizione: Articolo principale
Tipo di file: PDF EDITORIALE
Dimensione 555.81 kB
Formato Adobe PDF
555.81 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/125674
Citazioni
  • ???jsp.display-item.citation.pmc??? 18
  • Scopus 68
  • ???jsp.display-item.citation.isi??? 59
social impact