• Bacterial extracellular vesicles: towards realistic models for bacterial membranes in molecular interaction studies by surface plasmon resonance 

      Brilkov, Maxim; Stenbakk, Victoria; Jakubec, Martin; Vasskog, Terje; Kristoffersen, Tone; Cavanagh, Jorunn Pauline; Ericson, Johanna Ulrica; Isaksson, Johan Mattias; Flaten, Gøril Eide (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-12-13)
      One way to mitigate the ongoing antimicrobial resistance crisis is to discover and develop new classes of antibiotics. As all antibiotics at some point need to either cross or just interact with the bacterial membrane, there is a need for representative models of bacterial membranes and efficient methods to characterize the interactions with novel molecules -both to generate new knowledge and to ...
    • Biomimetic PVPA in vitro model for estimation of the intestinal drug permeability using fasted and fed state simulated intestinal fluids 

      Naderkhani, Elenaz; Vasskog, Terje; Flaten, Gøril Eide (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-06-20)
      A prerequisite for successful oral drug therapy is the drug’s ability to cross the gastrointestinal barrier. Considering the increasing number of new chemical entities in modern drug discovery, reliable and fast in vitro models are required for early and efficient prediction of intestinal permeability. To mimic the intestinal environment, use of biorelevant media may provide valuable information ...
    • Chitosan in Mucoadhesive Drug Delivery: Focus on Local Vaginal Therapy 

      Andersen, Toril; Bleher, Stefan; Flaten, Gøril Eide; Tho, Ingunn; Mattsson, Sofia; Skalko-Basnet, Natasa (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-01-07)
      Mucoadhesive drug therapy destined for localized drug treatment is gaining increasing importance in today’s drug development. Chitosan, due to its known biodegradability, bioadhesiveness and excellent safety profile offers means to improve mucosal drug therapy. We have used chitosan as mucoadhesive polymer to develop liposomes able to ensure prolonged residence time at vaginal site. Two types of ...
    • Chitosan-Based Nanomedicine to Fight Genital Candida Infections: Chitosomes 

      Andersen, Toril; Mishchenko, Ekaterina; Flaten, Gøril Eide; Sollid, Johanna U Ericson; Mattsson, Sofia; Tho, Ingunn; Skalko-Basnet, Natasa (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-03-04)
      Vaginal infections are associated with high recurrence, which is often due to a lack of efficient treatment of complex vaginal infections comprised of several types of pathogens, especially fungi and bacteria. Chitosan, a mucoadhesive polymer with known antifungal effect, could offer a great improvement in vaginal therapy; the chitosan-based nanosystem could both provide antifungal effects and ...
    • Current challenges and future perspectives in oral absorption research: An opinion of the UNGAP network 

      Vinarov, Zahari; Abrahamsson, Bertil; Artursson, Per; Batchelor, Hannah; Berben, Philippe; Bernkop-Schnürch, Andreas; Butler, James; Ceulemans, Jens; Davies, Nigel; Dupont, Didier; Flaten, Gøril Eide; Fotaki, Nikoletta; Griffin, Brendan T.; Jannin, Vincent; Keemink, Janneke; Kesisoglou, Filippos; Koziolek, Mirko; Kuentz, Martin; Mackie, Alan R.; Meléndez-Martínez, Antonio J.; McAllister, Mark; Müllertz, Anette; O'Driscoll, Caitriona M.; Parrott, Neil; Paszkowska, Jadwiga; Pavek, Petr; Porter, Christopher J.H.; Reppas, Christos; Stillhart, Cordula; Sugano, Kiyohiko; Toader, Elena; Valentová, Kateřina; Vertzoni, Maria; De Wildt, Saskia N.; Wilson, Clive G.; Augustijns, Patrick (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-02-18)
      Although oral drug delivery is the preferred administration route and has been used for centuries, modern drug discovery and development pipelines challenge conventional formulation approaches and highlight the insufficient mechanistic understanding of processes critical to oral drug absorption. This review presents the opinion of UNGAP scientists on four key themes across the oral absorption ...
    • Deformable liposomes for skin therapy with human epidermal growth factor: The effect of liposomal surface charge 

      Ternullo, Selenia; Basnet, Purusotam; Holsæter, Ann Mari; Flaten, Gøril Eide; de Weerd, Louis; Skalko-Basnet, Natasa (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-10-07)
      The topical administration of exogenous human epidermal growth factor (hEGF) is a promising approach for improved chronic wound therapy. To develop therapeutically superior hEGF formulation, we prepared hEGF-containing neutral (NDLs), cationic (CDLs) and anionic (ADLs) deformable liposomes (DLs), respectively, since it is expected that the liposomal surface charge can affect both the liposomal ...
    • Development of a biomimetic phospholipid vesicle-based permeation assay for the estimation of intestinal drug permeability 

      Naderkhani, Elenaz; Isaksson, Johan; Ryzhakov, Alexey; Flaten, Gøril Eide (Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
    • Drug loading to mesoporous silica carriers by solvent evaporation: A comparative study of amorphization capacity and release kinetics 

      Soltys, Marek; Zuza, David; Boleslavska, Tereza; Akhlasova, Sarah Machac; Balouch, Martin; Kovacik, Pavel; Beranek, Josef; Skalko-Basnet, Natasa; Flaten, Gøril Eide; Stefanec, Frantisek (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-08-08)
      The sorption of poorly aqueous soluble active pharmaceutical ingredients (API) to mesoporous silica carriers is an increasingly common formulation strategy for dissolution rate enhancement for this challenging group of substances. However, the success of this approach for a particular API depends on an array of factors including the properties of the porous carrier, the loading method, or the attempted ...
    • Drug permeability across a phospholipid vesicle based barrier: 3. Characterization of drug-membrane interactions and the effect of agitation on the barrier integrity and on the permeability 

      Flaten, Gøril Eide; Skar, Merete L.; Luthman, Kristina; Brandl, Martin (Journal article; Tidsskriftartikkel; Peer reviewed, 2007)
      Recently, we reported on the development and structural characterization of a phospholipid vesicle based barrier useful for medium throughput screening of passive drug permeability. Here, we investigate the physical and functional integrity of the phospholipid vesicle based barriers to agitation by stirring or shaking, and whether agitation affects drug permeability of sulpiride, metoprolol and ...
    • Drug permeability across a phospholipid vesicle based barrier: A novel approach for studying passive diffusion 

      Flaten, Gøril Eide; Dhanikula, Anand Babu; Luthman, Kristina; Brandl, Martin (Journal article; Tidsskriftartikkel; Peer reviewed, 2005-10)
      The aim of this study was to develop a novel predictive medium-throughput screening method for drug permeability, with use of a tight barrier of liposomes on a filter support. To our knowledge no one has succeeded in depositing membrane barriers without the use of inert solvent such as hexadecane. The first part of the study involved development of a protocol for preparation of these barriers, which ...
    • Drug permeability across a phospholipid vesicle-based barrier - 2. Characterization of barrier structure, storage stability and stability towards pH changes 

      Flaten, Gøril Eide; Bunjes, Heike; Luthman, Kristina; Brandl, Martin (Journal article; Tidsskriftartikkel; Peer reviewed, 2006-04-18)
      Recently we reported on the development of a phospholipid vesicle-based barrier as a medium throughput method for screening of drug permeability. The aim of this present study is to characterize the barrier structure, including an estimation of the amount of phospholipid within it, its storage stability and its stability over various pH ranges found in different parts of the gastrointestinal tract. ...
    • Drug permeability across a phospholipid vesicle-based barrier: 4. The effect of tensides, co-solvent and pH changes on barrier integrity and on drug permeability 

      Flaten, Gøril Eide; Luthman, Kristina; Vasskog, Terje; Brandl, Martin (Journal article; Tidsskriftartikkel; Peer reviewed, 2008-07-03)
      In this study the integrity of the recently developed phospholipid vesicle-based permeability barrier in the presence of a variety of co-solvents and tensides has been investigated. Also included are studies of the influence of these additives on drug permeation and the effect of pH changes on the permeability of ionogenic drug compounds. Permeability experiments using the hydrophilic model ...
    • Drug permeability profiling using cell-free permeation tools: Overview and applications 

      Berben, Philippe; Bauer-Brandl, Annette; Brandl, Martin; Faller, Bernard; Flaten, Gøril Eide; Jacobsen, Ann-Cathrine; Brouwers, Joachim; Augustijns, Patrick (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-04-13)
      Cell-free permeation systems are gaining interest in drug discovery and development as tools to obtain a reliable prediction of passive intestinal absorption without the disadvantages associated with cell- or tissue-based permeability profiling. Depending on the composition of the barrier, cell-free permeation systems are classified into two classes including (i) biomimetic barriers which are ...
    • Gene transfer potential of outer membrane vesicles of Acinetobacter baylyi and effects of stress on vesiculation 

      Fulsundar, Shweta; Harms, Klaus; Flaten, Gøril Eide; Johnsen, Pål Jarle; Chopade, Balu Ananda; Nielsen, Kaare Magne (Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
    • Going skin deep: a direct comparison of penetration potential of lipid-based nanovesicles on the isolated perfused human skin flap model 

      Ternullo, Selenia; de Weerd, Louis; Holsæter, Ann Mari; Flaten, Gøril Eide; Skalko-Basnet, Natasa (Journal article; Tidsskriftartikkel, 2017-09-12)
      Phospholipid-based nanocarriers are attractive drug carriers for improved local skin therapy. In the present study, the recently developed isolated perfused human skin flap (IPHSF) model was used to directly compare the skin penetration enhancing potential of the three commonly used nanocarriers, namely conventional liposomes (CLs), deformable liposomes (DLs) and solid lipid nanoparticles (SLNs). ...
    • Impact of mucin on drug diffusion: Development of a straightforward in vitro method for the determination of drug diffusivity in the presence of mucin 

      Falavigna, Margherita; Stein, Paul C.; Flaten, Gøril Eide; Di Cagno, Massimiliano Pio (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-02-17)
      Mucosal drug delivery accounts for various administration routes (i.e., oral, vaginal, ocular, pulmonary, etc.) and offers a vast surface for the permeation of drugs. However, the mucus layer which shields and lubricates all mucosal tissues can compromise drugs from reaching the epithelial site, thus affecting their absorption and therapeutic effect. Therefore, the effect of the mucus layer on drug ...
    • Improved Permeability of Acyclovir: Optimization of Mucoadhesive Liposomes Using the Phospholipid Vesicle-Based Permeation Assay 

      Naderkhani, Elenaz; Erber, Astrid; Skalko-Basnet, Natasa; Flaten, Gøril Eide (Journal article; Tidsskriftartikkel; Peer reviewed, 2014-01-06)
    • In vitro skin models as a tool in optimization of drug formulation 

      Flaten, Gøril Eide; Palac, Zora; Engesland, André; Filipović-Grčić, Jelena; Vanić, Željka; Skalko-Basnet, Natasa (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-07-30)
      (Trans)dermal drug therapy is gaining increasing importance in the modern drug development. To fully utilize the potential of this route, it is important to optimize the delivery of active ingredient/drug into/through the skin. The optimal carrier/vehicle can enhance the desired outcome of the therapy therefore the optimization of skin formulations is often included in the early stages of the ...
    • The isolated perfused human skin flap model: A missing link in skin penetration studies? 

      Ternullo, Selenia; de Weerd, Louis; Flaten, Gøril Eide; Holsæter, Ann Mari; Skalko-Basnet, Natasa (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-10-05)
      Development of effective (trans)dermal drug delivery systems requires reliable skinmodels to evaluate skin drug penetration. The isolated perfused human skin flap remainsmetabolically active tissue for up to 6 h during in vitro perfusion. We introduce the isolated perfused human skin flap as a close-to-in vivo skin penetration model. To validate the model's ability to evaluate skin drug penetration ...
    • Liposomal formulations of poorly soluble camptothecin: drug retention and biodistribution 

      Flaten, Gøril Eide; Chang, Ting-Tung; Phillips, William T.; Brandl, Martin; Bao, Ande; Goins, Beth (Journal article; Tidsskriftartikkel; Peer reviewed, 2012-12-05)
      Context: Camptothecin (CPT) represents a potent anticancer drug. Its therapeutic use however is impaired by both drug solubility, hydrolysis and protein interactions in vivo. Use of liposomes as drug formulation approach could overcome some of these challenges. <p>Objective: The objective of this study was to perform a mechanistic study of the incorporation and retention of the lipophilic parent ...