title: Predicting the release profile of small molecules from within the ordered nanostructured lipidic bicontinuous cubic phase using translational diffusion coefficients determined by PFG-NMR.
abstract: The ordered nanostructured lipidic bicontinuous cubic phase has demonstrated potential as a drug release material, due to its ability to encapsulate a wide variety of compounds, which may undergo sustained, diffusion controlled release over time. Control of drug release has been shown to depend on the nanostructural parameters of the lipid mesophase. Herein, the diffusion and release of two amino acids, encapsulated within a range of different lipidic cubic mesophases are investigated. Pulsed-field gradient NMR was used to determine the diffusion coefficient of the encapsulated amino acid, which was found to be correlated with the nanoscale diameter of the water channels within the cubic mesophase. This information was used to predict the release profiles of encapsulated compounds from within the cubic mesophase, which was verified by directly measuring the release of each amino acid in vitro. Predicted release profiles tracked reasonably close to the measured release profiles, indicating that NMR determined diffusion measurements can be used to predict release profiles.
authors.affiliation: School of Chemistry, University of Melbourne, VIC 3010, Australia and Bio21 Institute, University of Melbourne, VIC 3010, Australia.
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Meikle
authors.affiliation: Bio21 Institute, University of Melbourne, VIC 3010, Australia.
authors.forename: Shenggen
authors.initials: S
authors.lastname: Yao
authors.affiliation: School of Science, College of Science, Engineering and Health, RMIT University, 124 La Trobe Street, Melbourne, VIC 3000, Australia. calum.drummond@rmit.edu.au.
authors.forename: Alexandru
authors.initials: A
authors.lastname: Zabara
authors.affiliation: School of Science, College of Science, Engineering and Health, RMIT University, 124 La Trobe Street, Melbourne, VIC 3000, Australia. calum.drummond@rmit.edu.au.
authors.forename: Charlotte E
authors.initials: CE
authors.lastname: Conn
authors.affiliation: School of Science, College of Science, Engineering and Health, RMIT University, 124 La Trobe Street, Melbourne, VIC 3000, Australia. calum.drummond@rmit.edu.au.
authors.forename: Calum J
authors.identifier: http://orcid.org/0000-0001-7340-8611
authors.initials: CJ
authors.lastname: Drummond
authors.affiliation: School of Chemistry, University of Melbourne, VIC 3010, Australia and Bio21 Institute, University of Melbourne, VIC 3010, Australia.
authors.forename: Frances
authors.identifier: http://orcid.org/0000-0002-6484-2763
authors.initials: F
authors.lastname: Separovic