title: Hydrophobin-nanofibrillated cellulose stabilized emulsions for encapsulation and release of BCS class II drugs.
abstract: The purpose of this study was to construct biopolymer-based oil-in-water emulsion formulations for encapsulation and release of poorly water soluble model compounds naproxen and ibuprofen. Class II hydrophobin protein HFBII from Trichoderma reesei was used as a surfactant to stabilize the oil/water interfaces of the emulsion droplets in the continuous aqueous phase. Nanofibrillated cellulose (NFC) was used as a viscosity modifier to further stabilize the emulsions and encapsulate protein coated oil droplets in NFC fiber network. The potential of both native and oxidized NFC were studied for this purpose. Various emulsion formulations were prepared and the abilities of different formulations to control the drug release rate of naproxen and ibuprofen, used as model compounds, were evaluated. The optimal formulation for sustained drug release consisted of 0.01% of drug, 0.1% HFBII, 0.15% oxidized NFC, 10% soybean oil and 90% water phase. By comparison, the use of native NFC in combination with HFBII resulted in an immediate drug release for both of the compounds. The results indicate that these NFC originated biopolymers are suitable for pharmaceutical emulsion formulations. The native and oxidized NFC grades can be used as emulsion stabilizers in sustained and immediate drug release applications. Furthermore, stabilization of the emulsions was achieved with low concentrations of both HFBII and NFC, which may be an advantage when compared to surfactant concentrations of conventional excipients traditionally used in pharmaceutical emulsion formulations.
authors.affiliation: Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 Helsinki, Finland. Electronic address: heli.paukkonen@helsinki.fi.
authors.forename: Heli
authors.initials: H
authors.lastname: Paukkonen
authors.affiliation: Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 Helsinki, Finland.
authors.forename: Anni
authors.initials: A
authors.lastname: Ukkonen
authors.affiliation: VTT Technical Research Centre of Finland, P.O. Box 1000, FI-02044 VTT Espoo, Finland.
authors.forename: Geza
authors.initials: G
authors.lastname: Szilvay
authors.affiliation: Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 Helsinki, Finland; Department of Pharmaceutical and Pharmacological Sciences, via Marzalo 5, University of Padova, Padova, Italy.
authors.forename: Marjo
authors.initials: M
authors.lastname: Yliperttula
authors.affiliation: Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 Helsinki, Finland; Department of Chemistry and Bioengineering, Tampere University of Technology, P.O. Box 541, FI-33101 Tampere, Finland.
authors.forename: Timo
authors.initials: T
authors.lastname: Laaksonen
mesh_terms: D002482:Cellulose / Q000737:chemistry*; D003692:Delayed-Action Preparations / Q000737:chemistry; D065546:Drug Liberation; D004655:Emulsions; D005656:Fungal Proteins / Q000737:chemistry*; D007052:Ibuprofen / Q000737:chemistry*; D057139:Nanofibers / Q000737:chemistry*; D009288:Naproxen / Q000737:chemistry*; D009829:Oleic Acids / Q000737:chemistry; D013024:Soybean Oil / Q000737:chemistry; D014242:Trichoderma; D014783:Viscosity
chemical_list: D003692:Delayed-Action Preparations; D004655:Emulsions; D005656:Fungal Proteins; D009829:Oleic Acids; D009288:Naproxen; D013024:Soybean Oil; D002482:Cellulose; D007052:Ibuprofen; C033180:ethyl oleate
keywords: Drug release; Emulsions; Hydrophobin; Ibuprofen; Nanofibrillated cellulose; Naproxen