title: Electrosprayed nanoparticle delivery system for controlled release.
abstract: This study utilises an electrohydrodynamic technique to prepare core-shell lipid nanoparticles with a tunable size and high active ingredient loading capacity, encapsulation efficiency and controlled release. Using stearic acid and ethylvanillin as model shell and active ingredients respectively, we identify the processing conditions and ratios of lipid:ethylvanillin required to form nanoparticles. Nanoparticles with a mean size ranging from 60 to 70nm at the rate of 1.37×10(9) nanoparticles per minute were prepared with different lipid:ethylvanillin ratios. The polydispersity index was ≈21% and the encapsulation efficiency ≈70%. It was found that the rate of ethylvanillin release was a function of the nanoparticle size, and lipid:ethylvanillin ratio. The internal structure of the lipid nanoparticles was studied by transmission electron microscopy which confirmed that the ethylvanillin was encapsulated within a stearic acid shell. Fourier transform infrared spectroscopy analysis indicated that the ethylvanillin had not been affected. Extensive analysis of the release of ethylvanillin was performed using several existing models and a new diffusive release model incorporating a tanh function. The results were consistent with a core-shell structure.
authors.affiliation: Department of Biomedical Engineering, Sudan University of Science and Technology, PO Box 407, Khartoum, Sudan. Electronic address: megdi.eltayeb@sustech.edu.
authors.forename: Megdi
authors.initials: M
authors.lastname: Eltayeb
authors.affiliation: Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Old Road Campus Research Building, Headington OX3 7DQ, UK. Electronic address: eleanor.stride@eng.ox.ac.uk.
authors.forename: Eleanor
authors.initials: E
authors.lastname: Stride
authors.affiliation: Department of Mechanical Engineering, University College London, Torrington Place, London WC1E 7JE, UK. Electronic address: m.edirisinghe@ucl.ac.uk.
authors.forename: Mohan
authors.initials: M
authors.lastname: Edirisinghe
authors.affiliation: London Centre for Nanotechnology, Gordon Street, London WC1H 0AH, UK; Department of Physics & Astronomy, University College London, Gower Street, London WC1E 6BT, UK. Electronic address: a.harker@ucl.ac.uk.
authors.forename: Anthony
authors.initials: A
authors.lastname: Harker
mesh_terms: D001547:Benzaldehydes / Q000737:chemistry; D046529:Microscopy, Electron, Transmission; D008958:Models, Molecular; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D017550:Spectroscopy, Fourier Transform Infrared; D013229:Stearic Acids / Q000737:chemistry; D013500:Surface Tension; D014783:Viscosity; D014961:X-Ray Diffraction
chemical_list: D001547:Benzaldehydes; D013229:Stearic Acids; C031183:stearic acid; C045941:ethyl vanillin
keywords: Controlled release; Electrohydrodynamic processing; Lipid nanoparticles