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Bock F, Hu A, Cicale V, Larsen SW, Lu X, Østergaard J. Development of UV-Vis Imaging Compatible Chromatographic Matrix with Application for Injectable Formulation Characterization. Anal Chem 2023; 95:15861-15866. [PMID: 37857348 DOI: 10.1021/acs.analchem.3c03648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2023]
Abstract
Transport within human tissue matrices, e.g., the subcutaneous tissue, exhibits some resemblance to chromatographic processes. Here, a porous matrix comprising agarose beads compatible with UV-vis imaging was developed for a parallel piped rectangular flow cell (4 mm light path). Introduction of high-molecular weight dextrans (Mr ∼ 200000 and ∼500000) at 10% (w/v) rendered imaging possible by providing optical clearing of the turbid porous matrix, resulting in improved transmittance as well as resolution (from 400 to 180 μm) at 280 nm, as well as 520 nm. The interplay between diffusive and convective transport at 0 < Pe ≤ 28 was visualized at 280 nm upon injection of dexamethasone suspensions. Real-time UV-vis imaging showed in-flow cell the effect of incorporating ion-exchange resins on the retention of infliximab, lysozyme, and α-lactalbumin. The ion-exchange matrix may serve as a surrogate for polyelectrolytes in the subcutaneous tissue, assessing the potential role of electrostatic interactions of biotherapeutics upon injection. UV-vis imaging of size-exclusion chromatographic matrixes may be of interest in its own right and potentially develop into a characterization tool for injectables.
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Affiliation(s)
- Frederik Bock
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Angela Hu
- Bristol Myers Squibb Company, Drug Product Development, 1 Squibb Drive, New Brunswick, New Jersey 08901, United States
| | - Vincent Cicale
- Bristol Myers Squibb Company, Drug Product Development, 1 Squibb Drive, New Brunswick, New Jersey 08901, United States
| | - Susan Weng Larsen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Xujin Lu
- Bristol Myers Squibb Company, Drug Product Development, 1 Squibb Drive, New Brunswick, New Jersey 08901, United States
| | - Jesper Østergaard
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
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2
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Hedengran A, Freiberg JC, Hansen PM, Jacobsen J, Larsen SW, Harloff‐Helleberg S, Freude K, Boix‐Lemonche G, Petrovski G, Heegaard S, Kolko M. Generic benzalkonium chloride-preserved travoprost eye drops are not identical to the branded polyquarternium-1-preserved travoprost eye drop: Effect on cultured human conjunctival goblet cells and their physicochemical properties. Acta Ophthalmol 2022; 100:819-827. [PMID: 35527390 PMCID: PMC9790398 DOI: 10.1111/aos.15163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 03/07/2022] [Accepted: 04/18/2022] [Indexed: 12/30/2022]
Abstract
PURPOSE To investigate the effect of polyquaternium-1 (PQ)-preserved and benzalkonium chloride (BAK)-preserved travoprost eye drops on viability of primary human conjunctival goblet cell (GC) cultures and on secretion of mucin and cytokines. Furthermore, to evaluate the physicochemical properties of the branded travoprost eye drop Travatan® and available generics. METHODS The effect of travoprost eye drops was evaluated on GC cultures. Cell viability was assessed through lactate dehydrogenase (LDH) and tetrazolium dye (MTT) colorimetric assays. Mucin secretion was evaluated by immunohistochemical staining. Secretion of interleukin (IL)-6 and IL-8 was measured using BD Cytometric Bead Arrays. pH, viscosity, droplet mass, osmolality and surface tension were measured for all included eye drops. RESULTS In the LDH assay, BAK travoprost caused significant GC loss after 2 hrs of incubation compared to the control. PQ travoprost caused no GC loss at any time point. Both PQ- and BAK travoprost caused secretion of mucin to the cytoplasma. No difference in IL-6 and IL-8 secretion was identified compared to controls. The pH values for the generics were lower (pH 6.0) than the pH value for Travatan (pH 6.7; p < 0.0001). The viscosity was lowest for Travatan, while the mean droplet mass was higher for Travatan (35 mg) than the generics (28-30 mg; p ≤ 0.0318). The osmolality and surface tension did not differ between the eye drops investigated. CONCLUSION BAK travoprost caused GC loss, indicating that PQ preservation may be preferable in treatment of glaucoma. Furthermore, physicochemical properties of branded and generic travoprost eye drops can not be assumed to be identical.
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Affiliation(s)
- Anne Hedengran
- Department of Drug Design and PharmacologyUniversity of CopenhagenCopenhagenDenmark,Department of OphthalmologyCopenhagen University Hospital, RigshospitaletGlostrupDenmark
| | | | - Pernille May Hansen
- Department of Drug Design and PharmacologyUniversity of CopenhagenCopenhagenDenmark,Department of OphthalmologyCopenhagen University Hospital, RigshospitaletGlostrupDenmark
| | - Jette Jacobsen
- Department of PharmacyUniversity of CopenhagenCopenhagenDenmark
| | | | | | - Kristine Freude
- Pathobiological Sciences, Department of Veterinary and Animal SciencesUniversity of CopenhagenFrederiksberg CDenmark
| | - Gerard Boix‐Lemonche
- Center for Eye Research, Department of OphthalmologyOslo University Hospital and Institute for Clinical Medicine, Faculty of Medicine, University of OsloOsloNorway
| | - Goran Petrovski
- Center for Eye Research, Department of OphthalmologyOslo University Hospital and Institute for Clinical Medicine, Faculty of Medicine, University of OsloOsloNorway
| | - Steffen Heegaard
- Department of OphthalmologyCopenhagen University Hospital, RigshospitaletGlostrupDenmark,Department of PathologyUniversity Hospital RigshospitaletCopenhagenDenmark
| | - Miriam Kolko
- Department of Drug Design and PharmacologyUniversity of CopenhagenCopenhagenDenmark,Department of OphthalmologyCopenhagen University Hospital, RigshospitaletGlostrupDenmark
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Mertz N, Bock F, Østergaard J, Yaghmur A, Weng Larsen S. Investigation of diclofenac release and dynamic structural behavior of non-lamellar liquid crystal formulations during in situ formation by UV-Vis imaging and SAXS. Int J Pharm 2022; 623:121880. [PMID: 35661744 DOI: 10.1016/j.ijpharm.2022.121880] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 05/25/2022] [Accepted: 05/26/2022] [Indexed: 10/18/2022]
Abstract
In situ formation of high viscous inverse lyotropic non-lamellar liquid crystalline phases is a promising approach for sustained drug delivery in the joint. The in situ forming process on exposure of two diclofenac-loaded preformulations to aqueous media was characterized with respect to depot size and shape, initial release and structural transitions using UV-Vis imaging and spatially and time-resolved synchrotron small-angle X-ray scattering (SAXS). The preformulations consisted of 10 % (w/w) ethanol, 10 % (w/w) water and a binary lipid mixture of glycerol monooleate (GMO):1,2-dioleoyl-sn-glycero-3-phospho-rac-(1-glycerol) (DOPG) or GMO:medium chain triglycerides (MCT). Upon injection of preformulations into an employed injection-cell containing excess of bio-relevant medium, rapid generation of liquid crystalline depots was observed. UV-Vis images and constructed 2D SAXS maps of the injection-cell showed depots with different shapes and sizes, and features with high nanostructural heterogeneity. More extensive swelling of the GMO:DOPG-based preformulation was observed compared to the GMO:MCT-based preformulation. The UV image analysis found that a higher amount of diclofenac was released in the image area after 20 h from the GMO:MCT-depot compared to the GMO:DOPG-depot. The injection-cell setup employing UV-Vis imaging and synchrotron SAXS constitutes an attractive approach for evaluating the in situ forming processes of liquid crystalline depots.
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Affiliation(s)
- Nina Mertz
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
| | - Frederik Bock
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
| | - Jesper Østergaard
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
| | - Anan Yaghmur
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
| | - Susan Weng Larsen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
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Huang J, Jacobsen J, Genina N, Larsen SW, Nielsen HM, Müllertz A, Mu H. Investigating the effect of graphene oxide in chitosan/alginate-based foams on the release and antifungal activity of clotrimazole in vitro. Eur J Pharm Sci 2022; 174:106204. [PMID: 35550171 DOI: 10.1016/j.ejps.2022.106204] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 05/03/2022] [Accepted: 05/08/2022] [Indexed: 12/14/2022]
Abstract
Polyelectrolyte complexes (PECs) have been used as the matrix of solid foams for drug delivery. This study aimed at investigating the effect of graphene oxide (GO) and the composition of excipients in chitosan/alginate-based buccal foams on the clotrimazole release and antifungal activities. The investigation has been focused on the interactions of the drug with excipients in the foams, and the changes of ionization degree upon exposure to various media are discussed. The solid foams were prepared by mixing the excipients and clotrimazole via probe sonication, followed by a freeze-drying method. The pH values of the formulations were measured during the foam preparation process to estimate the ionization degree of clotrimazole and the other excipients. The foam matrix was the PECs between the cationic chitosan and anionic alginate. The mechanical strength of clotrimazole-loaded foams was lower than that of drug-free foams due to the positively charged clotrimazole interacting with the anionic alginate and interfering the PECs between chitosan and alginate. Addition of GO in the clotrimazole-loaded matrix made the foams mechanically stronger and contributed to a faster release of clotrimazole from the buccal foams by disrupting the electrostatic interactions between alginate and clotrimazole. However, addition of 1 wt% GO in the formulations didn't affect the antifungal activity of clotrimazole-loaded foams significantly. A lower amount GO in the formulation may be required for enhancing the antifungal effect, which should be further investigated in future.
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Affiliation(s)
- J Huang
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2100, Denmark
| | - J Jacobsen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2100, Denmark
| | - N Genina
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2100, Denmark
| | - S W Larsen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2100, Denmark
| | - H M Nielsen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2100, Denmark
| | - A Müllertz
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2100, Denmark
| | - H Mu
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2100, Denmark.
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5
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Bock F, Bøtker JP, Larsen SW, Lu X, Østergaard J. Methodological Considerations in Development of UV Imaging for Characterization of Intra-Tumoral Injectables Using cAMP as a Model Substance. Int J Mol Sci 2022; 23:ijms23073599. [PMID: 35408971 PMCID: PMC8998202 DOI: 10.3390/ijms23073599] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 03/17/2022] [Accepted: 03/23/2022] [Indexed: 12/19/2022] Open
Abstract
A UV imaging release-testing setup comprising an agarose gel as a model for tumorous tissue was developed. The setup was optimized with respect to agarose concentration (0.5% (w/v)), injection procedure, and temperature control. A repeatable injection protocol was established allowing injection into cavities with well-defined geometries. The effective resolution of the SDi2 UV imaging system is 30-80 µm. The linear range of the imaging system is less than that of typical spectrophotometers. Consequently, non-linear cAMP calibration curves were applied for quantification at 280 nm. The degree of deviation from Beer's law was affected by the background absorbance of the gel matrix. MATLAB scripts provided hitherto missing flexibility with respect to definition and utilization of quantification zones, contour lines facilitating visualization, and automated, continuous data analysis. Various release patterns were observed for an aqueous solution and in situ forming Pluronic F127 hydrogel and PLGA implants containing cAMP as a model for STING ligands. The UV imaging and MATLAB data analysis setup constituted a significant technical development in terms of visualizing behavior for injectable formulations intended for intra-tumoral delivery, and, thereby, a step toward establishment of a bio-predictive in vitro release-testing method.
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Affiliation(s)
- Frederik Bock
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark; (F.B.); (J.P.B.); (S.W.L.)
| | - Johan Peter Bøtker
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark; (F.B.); (J.P.B.); (S.W.L.)
| | - Susan Weng Larsen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark; (F.B.); (J.P.B.); (S.W.L.)
| | - Xujin Lu
- Bristol Myers Squibb Company, Drug Product Development, 1 Squibb Drive, New Brunswick, NJ 08901, USA;
| | - Jesper Østergaard
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark; (F.B.); (J.P.B.); (S.W.L.)
- Correspondence: ; Tel.: +45-35336138
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Müllertz O, Hedengran A, Mouhammad ZA, Freiberg J, Nagymihály R, Jacobsen J, Larsen SW, Bair J, Utheim T, Dartt DA, Heegaard S, Petrovski G, Kolko M. Impact of benzalkonium chloride-preserved and preservative-free latanoprost eye drops on cultured human conjunctival goblet cells upon acute exposure and differences in physicochemical properties of the eye drops. BMJ Open Ophthalmol 2022; 6:e000892. [PMID: 34993350 PMCID: PMC8689192 DOI: 10.1136/bmjophth-2021-000892] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 11/30/2021] [Indexed: 01/09/2023] Open
Abstract
Objective To investigate the short-term impact on human conjunctival goblet cell (GC) survival and mucin release of acute exposure to benzalkonium chloride (BAK) preserved and preservative-free (PF) 0.005% (w/v) latanoprost (LT) eye drops, and to compare the eye drops’ physicochemical properties. Methods and analysis Primary GC cultures were established from human conjunctival donor tissue. The impact of eye drops on GC survival was assessed using a lactate dehydrogenase assay. Mucin release was evaluated through mucin-specific immunostaining. pH value, osmolality, drop mass and surface tension for all LT eye drops were measured. Results After application with PF-LT for 30 min (min), the GC survival was maintained compared with control (p=0.9941), while all BAK-LT eye drops reduced survival with approximately 30% (p<0.02). Following application with PF-LT for 30 min, mucin was found around the GC nucleus, as seen in the vehicle control, indicating no secretion. In contrast, BAK-LT caused diffuse staining of mucin, similar to the secretagogue histamine, indicating stimulation of secretion. The pH value of the BAK-LT and PF-LT eye drops were 6.0–6.9 and 6.8, respectively. The osmolality was 258–288 mOsm/kg for the BAK-LT eye drops and 276 for PF-LT eye drops. The mean drop mass was 26–31 mg for the BAK-LT eye drops and 30 mg for PF-LT. The surface tension was lower for all BAK-LT eye drops (31.1–32.1 mN/m) compared with PF-LT (42 mN/m). Conclusion PF-LT compared with various branded and generic LT preparations containing BAK are less cytotoxic when applied to cultured GCs.
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Affiliation(s)
- Olivia Müllertz
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Anne Hedengran
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark.,Department of Ophthalmology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Zaynab Ahmad Mouhammad
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Josefine Freiberg
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Richárd Nagymihály
- Center for Eye Research, Department of Ophthalmology, Oslo University Hospital and Institute for Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Jette Jacobsen
- Department of Pharmacy, University of Copenhagen, Copenhagen, Denmark
| | - Susan Weng Larsen
- Department of Pharmacy, University of Copenhagen, Copenhagen, Denmark
| | - Jeffrey Bair
- Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Schepens Eye Research Institute, Boston, Massachusetts, USA
| | - Tor Utheim
- Department of Medical Biochemistry, Oslo Universitetssykehus, Oslo, Norway.,Department of Ophthalmology, Sørlandet Hospital Arendal, Arendal, Norway
| | - Darlene A Dartt
- Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Schepens Eye Research Institute, Boston, Massachusetts, USA
| | - Steffen Heegaard
- Department of Ophthalmology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.,Department of Pathology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Goran Petrovski
- Center for Eye Research, Department of Ophthalmology, Oslo University Hospital and Institute for Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Miriam Kolko
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark.,Department of Ophthalmology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
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Mertz N, Yaghmur A, Østergaard J, Amenitsch H, Larsen SW. Spatially and time-resolved SAXS for monitoring dynamic structural transitions during in situ generation of non-lamellar liquid crystalline phases in biologically relevant media. J Colloid Interface Sci 2021; 602:415-425. [PMID: 34144300 DOI: 10.1016/j.jcis.2021.06.031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 05/28/2021] [Accepted: 06/06/2021] [Indexed: 10/21/2022]
Abstract
Formation of high viscous inverse lyotropic liquid crystalline phases in situ upon exposure of low viscous drug-loaded lipid preformulations to synovial fluid provides a promising approach for design of depot formulations for intra-articular drug delivery. Rational formulation design relies on a fundamental understanding of the synovial fluid-mediated dynamic structural transitions occurring at the administration site. At conditions mimicking the in vivo situation, we investigated in real-time such transitions at multiple positions by synchrotron small-angle X-ray scattering (SAXS) combined with an injection-cell. An injectable diclofenac-loaded quaternary preformulation consisting of 72/8/10/10% (w/w) glycerol monooleate/1,2-dioleoyl-glycero-3-phospho-rac-(1-glycerol)/ethanol/water was injected into hyaluronic acid solution or synovial fluid. A fast generation of a coherent drug depot of inverse bicontinuous Im3m and Pn3m cubic phases was observed. Through construction of 2D spatial maps from measurements performed 60 min after injection of the preformulation, it was possible to differentiate liquid crystalline rich- and excess hyaluronic acid solution- or synovial fluid-rich regimes. Synchrotron SAXS findings confirmed that the exposure of the preformulation to the media leads to alterations in structural features in position- and time-dependent manners. Effects of biologically relevant medium composition on the structural features, and implications for development of formulations with sustained drug release properties are highlighted.
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Affiliation(s)
- Nina Mertz
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Anan Yaghmur
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Jesper Østergaard
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Heinz Amenitsch
- Institute of Inorganic Chemistry, Graz University of Technology, Graz, Austria.
| | - Susan Weng Larsen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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Puggaard RS, Ingelsrud LH, Jacobsen S, Kjellberg J, Bandholm T, Hölmich P, Boesen M, Bliddal H, Skou ST, Schrøder HM, Larsen SW, Møller A, Ziegler C, Troelsen A. Establishing research priorities related to osteoarthritis care via stakeholder input from patients. Dan Med J 2021; 68:A09200683. [PMID: 33543702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
INTRODUCTION Stakeholder involvement in research is emphasised to improve relevance. We aimed to identify, define and prioritise important research topics seen from the point of view of people with osteoarthritis (OA). METHODS We invited 1,315 members of the user panel of the Danish Rheumatism Association to answer an electronic survey that included; 1) an open-ended question about important research topics (free-text response option), 2) 15 predefined research topics to be rated for importance and 3) predefined topics grouped into four categories in which the most important was prioritised. Free-text responses were analysed using content analysis. RESULTS Out of 850 (65%) respondents, 483 had OA (mean ± standard deviation age 60.3 ± 10.2 years, 91% female). From the free-text responses, we identified seven research topics; 1) diagnostics, 2) prevention, 3) side effects, 4) treatment, 5) aetiology, 6) being young with OA and 7) quality of life. For "treatment", we identified seven subtopics. Out of all topics and subtopics, "pain management" was the most frequently highlighted. All predefined topics were rated as "very important" or "somewhat important" by more than 75% of the respondents. The top prioritised topics within each category were 1) improving the diagnosis, 2) individualised treatment, 3) shared decision-making and 4) cross-sector collaboration and collaboration between professionals. CONCLUSIONS We identified research topics that were important in the eyes of people with OA and found that "pain management" was particularly emphasised. FUNDING none. TRIAL REGISTRATION not relevant.
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Li Z, Sun Y, Bar-Shalom D, Mu H, Larsen SW, Jensen H, Østergaard J. Towards functional characterization of excipients for oral solid dosage forms using UV-vis imaging. Liberation, release and dissolution. J Pharm Biomed Anal 2020; 194:113789. [PMID: 33298380 DOI: 10.1016/j.jpba.2020.113789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 11/18/2020] [Accepted: 11/19/2020] [Indexed: 12/13/2022]
Abstract
The purpose of this study was to investigate whole-dosage form UV-vis imaging as a potential tool for functional characterization of excipients used in solid oral dosage forms. To this end, tablets (average mass 260.0 mg, 224.5 mg and 222.1 mg) containing theophylline anhydrate (20 % w/w), 1% (w/w) magnesium stearate, and 79 % (w/w) of either microcrystalline cellulose (MCC, Avicel PH 101) or hydroxypropyl methylcellulose (HPMC, Methocel K15 M or K100 M) were prepared as model systems. Drug liberation from tablets was studied in 0.01 M HCl at 37 °C using a Sirius SDi2 equipped with a USP IV type flow cell comprising a UV-vis imaging detector operating at 255 nm and 520 nm. The effluent from the flow cell was passed through a downstream spectrophotometer, and UV-vis spectra in the wavelength range 200-800 nm were recorded every 2 min. The erosion and swelling behavior of the MCC tablets and HPMC K15 M and K100 M tablets were visualized in real time. The swelling of HPMC K15 M and K100 M containing tablets was assessed quantitatively as changes in tablet diameter measured at 520 nm, and was clearly distinguished from the swelling of the MCC tablets. Namely, an increment of 2.5 mm in diameter was determined for the HPMC tablets while the MCC tablets increased by 0.5-1 mm in diameter. Gel layers of variable thickness were observed only for the HPMC K15 M and K100 M tablets. In addition, a relatively high initial liberation rate of theophylline was found for the MCC tablets as compared to the HPMC tablets. UV-vis imaging revealed features of liberation not revealed by simply measuring drug concentration in the dissolution media or by visual assessment. It may be sufficiently sensitive to be further developed for functional characterization of excipients and provide insights into drug-excipient interactions likely to be useful in formulation development.
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Affiliation(s)
- Zhuoxuan Li
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100, Copenhagen, Denmark.
| | - Yu Sun
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100, Copenhagen, Denmark.
| | - Daniel Bar-Shalom
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100, Copenhagen, Denmark; Bioneer: Farma, Universitetsparken 2, DK-2100, Copenhagen, Denmark.
| | - Huiling Mu
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100, Copenhagen, Denmark.
| | - Susan Weng Larsen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100, Copenhagen, Denmark.
| | - Henrik Jensen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100, Copenhagen, Denmark.
| | - Jesper Østergaard
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100, Copenhagen, Denmark.
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Li Z, Mu H, Larsen SW, Jensen H, Østergaard J. Initial Leuprolide Acetate Release from Poly(d,l-lactide-co-glycolide) in Situ Forming Implants as Studied by Ultraviolet–Visible Imaging. Mol Pharm 2020; 17:4522-4532. [DOI: 10.1021/acs.molpharmaceut.0c00625] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Zhuoxuan Li
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 København Ø, Denmark
| | - Huiling Mu
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 København Ø, Denmark
| | - Susan Weng Larsen
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 København Ø, Denmark
| | - Henrik Jensen
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 København Ø, Denmark
| | - Jesper Østergaard
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 København Ø, Denmark
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11
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Storgaard IH, Kristensen J, Larsen C, Mertz N, Østergaard J, Larsen SW. Diclofenac Prodrugs for Intra-articular Depot Injectables: In Vitro Hydrolysis and Species Variation. J Pharm Sci 2020; 109:1529-1536. [DOI: 10.1016/j.xphs.2020.01.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 11/26/2019] [Accepted: 01/03/2020] [Indexed: 01/18/2023]
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Bock F, Lin E, Larsen C, Jensen H, Huus K, Larsen SW, Østergaard J. Towards in vitro in vivo correlation for modified release subcutaneously administered insulins. Eur J Pharm Sci 2020; 145:105239. [PMID: 31987985 DOI: 10.1016/j.ejps.2020.105239] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 01/03/2020] [Accepted: 01/23/2020] [Indexed: 11/29/2022]
Abstract
Therapeutic proteins and peptides are mainly administrated by subcutaneous injection. In vitro release testing of subcutaneous injectables performed using methods that take the structure and environment of the subcutaneous tissue into account may improve predictability of the in vivo behavior and thereby facilitate establishment of in vitro in vivo correlations. The aim of the study was to develop a biopredictive flow-through in vitro release method with a gel-type matrix for subcutaneously administered formulations and to explore the possibility of establishing a level A in vitro in vivo correlation for selected insulin products. A novel gel-based flow-through method with the incorporation of an injection step was used to assess selected commercial insulin formulations with different duration of action (Actrapid®, Mixtard® 30, Insulatard®, Lantus®). The in vitro release method provided the correct rank ordering in relation to the in vivo performance. For the modified release insulins Insulatard® and Lantus®, an in vitro in vivo correlation using non-linear time scaling was established based on the in vitro release data and in vivo subcutaneous absorption data of the 125I-labeled insulins taken from literature. Predicted absorption profiles were constructed using the in vitro in vivo correlation and subsequently converted into simulated plasma profiles. The approach taken may be of wider utility in characterizing injectables for subcutaneous administration.
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Affiliation(s)
- Frederik Bock
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, Copenhagen DK-2100, Denmark
| | - Eva Lin
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, Copenhagen DK-2100, Denmark; Global Research Technologies, Novo Nordisk A/S, Novo Nordisk Park, Måløv DK-2760, Denmark
| | - Claus Larsen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, Copenhagen DK-2100, Denmark
| | - Henrik Jensen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, Copenhagen DK-2100, Denmark
| | - Kasper Huus
- Global Research Technologies, Novo Nordisk A/S, Novo Nordisk Park, Måløv DK-2760, Denmark
| | - Susan Weng Larsen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, Copenhagen DK-2100, Denmark
| | - Jesper Østergaard
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, Copenhagen DK-2100, Denmark.
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Mertz N, Østergaard J, Yaghmur A, Larsen SW. Transport characteristics in a novel in vitro release model for testing the performance of intra-articular injectables. Int J Pharm 2019; 566:445-453. [DOI: 10.1016/j.ijpharm.2019.04.083] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 04/12/2019] [Accepted: 04/13/2019] [Indexed: 12/25/2022]
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Prajapati R, Larsen SW, Yaghmur A. Citrem–phosphatidylcholine nano-self-assemblies: solubilization of bupivacaine and its role in triggering a colloidal transition from vesicles to cubosomes and hexosomes. Phys Chem Chem Phys 2019; 21:15142-15150. [DOI: 10.1039/c9cp01878f] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
In concentration- and lipid composition-dependent manners, bupivacaine triggers lamellar–nonlamellar phase transitions in citrem/soy phosphatidylcholine nanodispersions.
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Affiliation(s)
- Rama Prajapati
- Department of Pharmacy, Faculty of Health and Medical Sciences
- University of Copenhagen
- DK-2100 Copenhagen Ø
- Denmark
| | - Susan Weng Larsen
- Department of Pharmacy, Faculty of Health and Medical Sciences
- University of Copenhagen
- DK-2100 Copenhagen Ø
- Denmark
| | - Anan Yaghmur
- Department of Pharmacy, Faculty of Health and Medical Sciences
- University of Copenhagen
- DK-2100 Copenhagen Ø
- Denmark
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Mertz N, Larsen SW, Kristensen J, Østergaard J, Larsen C. Long-Acting Diclofenac Ester Prodrugs for Joint Injection: Kinetics, Mechanism of Degradation, and In Vitro Release From Prodrug Suspension. J Pharm Sci 2016; 105:3079-3087. [PMID: 27475785 DOI: 10.1016/j.xphs.2016.06.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 05/26/2016] [Accepted: 06/10/2016] [Indexed: 11/16/2022]
Abstract
A prodrug approach for local and sustained diclofenac action after injection into joints based on ester prodrugs having a pH-dependent solubility is presented. Inherent ester prodrug properties influencing the duration of action include their pH-dependent solubility and charge state, as well as susceptibility to undergo esterase facilitated hydrolysis. In this study, physicochemical properties and pH rate profiles of 3 diclofenac ester prodrugs differing with respect to the spacer carbon chain length between the drug and the imidazole-based promoiety were determined and a rate equation for prodrug degradation in aqueous solution in the pH range 1-10 was derived. In the pH range 6-10, the prodrugs were subject to parallel degradation to yield diclofenac and an indolinone derivative. The prodrug degradation was found to be about 6-fold faster in 80% (vol/vol) human plasma as compared to 80% (vol/vol) human synovial fluid with 2-(1-methyl-1H-imidazol-2-yl)ethyl 2-(2-(2,6 dichlorophenyl)amino)phenylacetate being the poorest substrate toward enzymatic cleavage. The conversion and release of parent diclofenac from prodrug suspensions in vitro were studied using the rotating dialysis model. The results suggest that it is possible to alter and control dissolution and reconversion behavior of the diclofenac prodrugs, thus making the prodrug approach feasible for local and sustained diclofenac action after joint injection.
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Affiliation(s)
- Nina Mertz
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Susan Weng Larsen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jesper Kristensen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jesper Østergaard
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Claus Larsen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Dep-Xplora ApS, Gammelbyvej 17, Lejre DK-4320, Denmark.
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Nilsson C, Østergaard J, Larsen SW, Larsen C, Urtti A, Yaghmur A. PEGylation of phytantriol-based lyotropic liquid crystalline particles--the effect of lipid composition, PEG chain length, and temperature on the internal nanostructure. Langmuir 2014; 30:6398-6407. [PMID: 24833115 DOI: 10.1021/la501411w] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Poly(ethylene glycol)-grafted 1,2-distearoyl-sn-glycero-3-phosphoethanolamines (DSPE-mPEGs) are a family of amphiphilic lipopolymers attractive in formulating injectable long-circulating nanoparticulate drug formulations. In addition to long circulating liposomes, there is an interest in developing injectable long-circulating drug nanocarriers based on cubosomes and hexosomes by shielding and coating the dispersed particles enveloping well-defined internal nonlamellar liquid crystalline nanostructures with hydrophilic PEG segments. The present study attempts to shed light on the possible PEGylation of these lipidic nonlamellar liquid crystalline particles by using DSPE-mPEGs with three different block lengths of the hydrophilic PEG segment. The effects of lipid composition, PEG chain length, and temperature on the morphology and internal nanostructure of these self-assembled lipidic aqueous dispersions based on phytantriol (PHYT) were investigated by means of synchrotron small-angle X-ray scattering and Transmission Electron Cryo-Microscopy. The results suggest that the used lipopolymers are incorporated into the water-PHYT interfacial area and induce a significant effect on the internal nanostructures of the dispersed submicrometer-sized particles. The hydrophilic domains of the internal liquid crystalline nanostructures of these aqueous dispersions are functionalized, i.e., the hydrophilic nanochannels of the internal cubic Pn3m and Im3m phases are significantly enlarged in the presence of relatively small amounts of the used DSPE-mPEGs. It is evident that the partial replacement of PHYT by these PEGylated lipids could be an attractive approach for the surface modification of cubosomal and hexosomal particles. These PEGylated nanocarriers are particularly attractive in designing injectable cubosomal and hexosomal nanocarriers for loading drugs and/or imaging probes.
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Affiliation(s)
- Christa Nilsson
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen , Universitetsparken 2, DK-2100 Copenhagen, Denmark
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Nilsson C, Barrios-Lopez B, Kallinen A, Laurinmäki P, Butcher SJ, Raki M, Weisell J, Bergström K, Larsen SW, Østergaard J, Larsen C, Urtti A, Airaksinen AJ, Yaghmur A. SPECT/CT imaging of radiolabeled cubosomes and hexosomes for potential theranostic applications. Biomaterials 2013; 34:8491-503. [PMID: 23932247 DOI: 10.1016/j.biomaterials.2013.07.055] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 07/18/2013] [Indexed: 01/11/2023]
Abstract
We have developed a highly efficient method for the radiolabeling of phytantriol (PHYT)/oleic acid (OA)-based hexosomes based on the surface chelation of technetium-99m ((99m)Tc) to preformed hexosomes using the polyamine 1, 12-diamino-3, 6, 9-triazododecane (SpmTrien) as chelating agent. We also report on the unsuccessful labeling of cubosomes using the well-known chelating agent hexamethylpropyleneamine oxime (HMPAO). The (99m)Tc-labeled SpmTrien-hexosomes ((99m)Tc-SpmTrien-hexosomes) were synthesized with good radiolabeling (84%) and high radiochemical purity (>90%). The effect of radiolabeling on the internal nanostructure and the overall size of these aqueous dispersions was investigated by using synchrotron small angle X-ray scattering (SAXS), dynamic light scattering (DLS), and transmission electron cryo microscopy (cryo-TEM). Further, we show the utility of (99m)Tc-SpmTrien-hexosomes for the in vivo imaging of healthy mice using single photon emission computed tomography (SPECT) in combination with computed tomography (CT), i.e. SPECT/CT. SPECT/CT experiments of subcutaneously administered (99m)Tc-SpmTrien-hexosomes to the flank of mice showed a high stability in vivo allowing imaging of the distribution of the radiolabeled hexosomes for up to 24 h. These injected (99m)Tc-SpmTrien-hexosomes formed a deposit within the subcutaneous adipose tissue, displaying a high biodistribution of ≈ 343% injected dose/g tissue (%ID/g), with negligible uptake in other organs and tissues. The developed (99m)Tc labeling method for PHYT/OA-based hexosomes could further serve as a useful tool for investigating and imaging the in vivo performance of cubosomal and hexosomal drug nanocarriers.
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Affiliation(s)
- Christa Nilsson
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
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Thing M, Lu Y, Ågårdh L, Larsen C, Østergaard J, He W, Wu W, Larsen F, Larsen SW. Prolonged naproxen joint residence time after intra-articular injection of lipophilic solutions comprising a naproxen glycolamide ester prodrug in the rat. Int J Pharm 2013; 451:34-40. [DOI: 10.1016/j.ijpharm.2013.04.056] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Revised: 04/16/2013] [Accepted: 04/17/2013] [Indexed: 10/26/2022]
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Ye F, Xie Y, Jensen H, Larsen SW, Yaghmur A, Larsen C, Østergaard J. Interaction of Amino Acid and Dipeptide β-Naphthylamide Derivatives with Hyaluronic Acid and Human Serum Albumin Studied by Capillary Electrophoresis Frontal Analysis. Chromatographia 2012. [DOI: 10.1007/s10337-012-2369-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Ye F, Larsen SW, Yaghmur A, Jensen H, Larsen C, Østergaard J. Drug release into hydrogel-based subcutaneous surrogates studied by UV imaging. J Pharm Biomed Anal 2012; 71:27-34. [DOI: 10.1016/j.jpba.2012.07.024] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Accepted: 07/23/2012] [Indexed: 01/21/2023]
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21
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Nilsson C, Edwards K, Eriksson J, Larsen SW, Østergaard J, Larsen C, Urtti A, Yaghmur A. Characterization of oil-free and oil-loaded liquid-crystalline particles stabilized by negatively charged stabilizer citrem. Langmuir 2012; 28:11755-11766. [PMID: 22831645 DOI: 10.1021/la3021244] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The present study was designed to evaluate the effect of the negatively charged food-grade emulsifier citrem on the internal nanostructures of oil-free and oil-loaded aqueous dispersions of phytantriol (PHYT) and glyceryl monooleate (GMO). To our knowledge, this is the first report in the literature on the utilization of this charged stabilizing agent in the formation of aqueous dispersions consisting of well-ordered interiors (either inverted-type hexagonal (H(2)) phases or inverted-type microemulsion systems). Synchrotron small-angle X-ray scattering (SAXS) and cryogenic transmission electron microscopy (cryo-TEM) were used to characterize the dispersed and the corresponding nondispersed phases of inverted-type nonlamellar liquid-crystalline phases and microemulsions. The results suggest a transition between different internal nanostructures of the aqueous dispersions after the addition of the stabilizer. In addition to the main function of citrem as a stabilizer that adheres to the surface of the dispersed particles, it has a significant impact on the internal nanostructures, which is governed by the following factors: (1) its penetration between the hydrophobic tails of the lipid molecules and (2) its degree of incorporation into the lipid-water interfacial area. In the presence of citrem, the formation of aqueous dispersions with functionalized hydrophilic domains by the enlargement of the hydrophilic nanochannels of the internal H(2) phase in hexosomes and the hydrophilic core of the L(2) phase in emulsified microemulsions (EMEs) could be particularly attractive for solubilizing and controlling the release of positively charged drugs.
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Affiliation(s)
- Christa Nilsson
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
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Ye F, Larsen SW, Yaghmur A, Jensen H, Larsen C, Østergaard J. Real-time UV imaging of piroxicam diffusion and distribution from oil solutions into gels mimicking the subcutaneous matrix. Eur J Pharm Sci 2012; 46:72-8. [DOI: 10.1016/j.ejps.2012.02.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2011] [Revised: 01/27/2012] [Accepted: 02/16/2012] [Indexed: 12/23/2022]
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Yaghmur A, Rappolt M, Østergaard J, Larsen C, Larsen SW. Characterization of bupivacaine-loaded formulations based on liquid crystalline phases and microemulsions: the effect of lipid composition. Langmuir 2012; 28:2881-9. [PMID: 22247936 DOI: 10.1021/la203577v] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
This report details the structural characterization and the in vitro drug-release properties of different local anesthetic bupivacaine (BUP)-loaded inverted-type liquid crystalline phases and microemulsions. The effects of variations in the lipid composition and/or BUP concentration on the self-assembled nanostructures were investigated in the presence of the commercial distilled glycerol monooleate Myverol 18-99K (GMO) and medium-chain triglycerides (MCT). Synchrotron small-angle X-ray scattering (SAXS) and rotating dialysis cell model were used to characterize the BUP formulations and to investigate the in vitro BUP release profiles, respectively. The evaluation of SAXS data for the BUP-loaded GMO/MCT formulations indicates the structural transition of inverted-type bicontinuous cubic phase of the symmetry Pn3m → inverted-type hexagonal (H(2)) phase → inverted-type microemulsion (L(2)) with increasing MCT content (0-40 wt %). In the absence of MCT, the solubilization of BUP induces the transition of Pn3m → H(2) at pH 7.4; whereas a transition of Pn3m → (Pn3m + H(2)) is detected as the hydration is achieved at pH 6.0. To mimic the drug release and transport from in situ formed self-assembled systems after subcutaneous administration, the release experiments were performed by injecting low viscous stimulus-responsive precursors to a buffer in the dialysis cell leaving the surface area between the self-assembled system and the release medium variable. Our results suggest that the pH-dependent variations in the lipidic partition coefficient, K(l/w), between the liquid crystalline nanostructures and the surrounding buffer solution are significantly affecting BUP release rates. Thus, a first step toward understanding of the drug-release mechanism of this drug-delivery class has been undertaken tackling the influence of drug ionization as well as the type of the self-assembled nanostructure and its release kinetics under pharmaceutically relevant conditions.
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Affiliation(s)
- Anan Yaghmur
- Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark.
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Larsen SW, Frost AB, Østergaard J, Thomsen MH, Jacobsen S, Skonberg C, Hansen SH, Jensen HE, Larsen C. In vitro and in vivo characteristics of celecoxib in situ formed suspensions for intra-articular administration. J Pharm Sci 2011; 100:4330-7. [DOI: 10.1002/jps.22630] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2010] [Revised: 07/02/2010] [Accepted: 04/27/2011] [Indexed: 11/08/2022]
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Frost AB, Lindegaard C, Larsen F, Østergaard J, Larsen SW, Larsen C. Intra-articular injection of morphine to the horse: establishment of anin vitro–in vivorelationship. Drug Dev Ind Pharm 2011; 37:1043-8. [DOI: 10.3109/03639045.2011.559245] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Østergaard J, Ye F, Rantanen J, Yaghmur A, Larsen SW, Larsen C, Jensen H. Monitoring lidocaine single-crystal dissolution by ultraviolet imaging. J Pharm Sci 2011; 100:3405-3410. [PMID: 21387316 DOI: 10.1002/jps.22532] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2010] [Revised: 01/13/2011] [Accepted: 02/09/2011] [Indexed: 11/06/2022]
Abstract
Dissolution critically affects the bioavailability of Biopharmaceutics Classification System class 2 compounds. When unexpected dissolution behaviour occurs, detailed studies using high information content technologies are warranted. In the present study, an evaluation of real-time ultraviolet (UV) imaging for conducting single-crystal dissolution studies was performed. Using lidocaine as a model compound, the aim was to develop a setup capable of monitoring and quantifying the dissolution of lidocaine into a phosphate buffer, pH 7.4, under stagnant conditions. A single crystal of lidocaine was placed in the quartz dissolution cell and UV imaging was performed at 254 nm. Spatially and temporally resolved mapping of lidocaine concentration during the dissolution process was achieved from the recorded images. UV imaging facilitated the monitoring of lidocaine concentrations in the dissolution media adjacent to the single crystals. The concentration maps revealed the effects of natural convection due to density gradients on the dissolution process of lidocaine. UV imaging has great potential for in vitro drug dissolution testing.
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Affiliation(s)
- Jesper Østergaard
- Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark.
| | - Fengbin Ye
- Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Jukka Rantanen
- Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Anan Yaghmur
- Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Susan Weng Larsen
- Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Claus Larsen
- Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Henrik Jensen
- Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
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Østergaard J, Meng-Lund E, Larsen SW, Larsen C, Petersson K, Lenke J, Jensen H. Real-Time UV Imaging of Nicotine Release from Transdermal Patch. Pharm Res 2010; 27:2614-23. [DOI: 10.1007/s11095-010-0257-9] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Accepted: 08/19/2010] [Indexed: 11/25/2022]
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Pedersen BT, Ostergaard J, Larsen SW, Cornett C, Ankersen M, Larsen C. Physicochemical characteristics and in vitro release from oil-based vehicles of peptidomimetics: parenteral depots for intra-articular administration. Drug Dev Ind Pharm 2010; 37:62-71. [PMID: 20545510 DOI: 10.3109/03639045.2010.491831] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
RESULTS Basic physicochemical properties including their apparent solubility in aqueous buffer and vegetable oils of a series of 11 peptidomimetics varying with respect to chain length and degree of N-methylation were estimated. It was observed that the compounds in contact with water transformed into sticky, slowly dissolving semisolid materials. Based on these observations, the in vitro release behavior of selected peptide derivatives from oil solutions and in situ formed precipitates was investigated using a validated in vitro release model. CONCLUSION The results of this investigation suggest that both types of oil-based drug delivery systems might constitute alternative sustained release formulation principles of such amorphous peptide derivatives for the intra-articular route of administration.
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Affiliation(s)
- Brian Thoning Pedersen
- Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
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Frost AB, Larsen F, Ostergaard J, Larsen SW, Lindegaard C, Hansen HR, Larsen C. On the search for in vitro in vivo correlations in the field of intra-articular drug delivery: administration of sodium diatrizoate to the horse. Eur J Pharm Sci 2010; 41:10-5. [PMID: 20580670 DOI: 10.1016/j.ejps.2010.05.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Revised: 04/30/2010] [Accepted: 05/10/2010] [Indexed: 01/14/2023]
Abstract
Development of suitable in vitro release models for formulation development as well as quality control purposes has to be initiated in the early design phase of injectable depots. Optimally, construction of an in vitro release model may lead to the establishment of in vitro in vivo correlations. By using a model compound (sodium diatrizoate, DTZ), the purpose of this study was to investigate the possibility of establishing in vitro in vivo relations between the DTZ disappearance profile obtained from the donor compartment of the rotating dialysis cell model and the joint disappearance profile following intra-articular administration. In vitro experiments were conducted by applying solutions of DTZ to the donor compartment. In the in vivo experiments, five horses were subjected to both intravenous and intra-articular administration of an aqueous solution of 3.9 mg DTZ/kg. A strong relation (R(2)=0.99) was obtained between the disappearance data from the donor compartment of the in vitro model and the disappearance data from the synovial fluid after intra-articular administration of DTZ. Furthermore, a relation (R(2)=0.91) between the appearance data obtained from the acceptor compartment and the deconvolved appearance serum data upon intra-articular administration of DTZ was obtained. The correlations obtained in this study hold promise that the rotating dialysis cell model has a role in the prediction of the intra-articular fate of drugs injected as solutions.
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Affiliation(s)
- Anna Buus Frost
- Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark
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Larsen C, Larsen SW, Jensen H, Yaghmur A, Ostergaard J. Role of in vitro release models in formulation development and quality control of parenteral depots. Expert Opin Drug Deliv 2010; 6:1283-95. [PMID: 19941410 DOI: 10.1517/17425240903307431] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
This review article provides an assessment of advantages/limitations of the use of current in vitro release models to predict in vivo performance of parenteral sustained release products (injectable depots). As highlighted, key characteristics influencing the in vivo drug fate may vary with the route of administration and the type of sustained release formulation. To this end, an account is given on three representative injection sites (intramuscular, subcutaneous and intra-articular) as well as on in vitro release mechanism(s) of drugs from five commonly investigated depot principles (suspensions, microspheres, hydrogels, lipophilic solutions, and liposomes/other nano-size formulations). Current in vitro release models are, to a different extent, able to mimic the rate, transport and equilibrium processes that the drug substance may experience in the environment of the administration site. Their utility for the purpose of quality control including in vitro-in vivo correlations and formulation design is discussed.
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Affiliation(s)
- Claus Larsen
- University of Copenhagen, Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, Universitetsparken 2, DK-2100 Copenhagen, Denmark.
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Weng Larsen S, Larsen C. Critical factors influencing the in vivo performance of long-acting lipophilic solutions--impact on in vitro release method design. AAPS J 2009; 11:762-70. [PMID: 19894123 DOI: 10.1208/s12248-009-9153-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2009] [Accepted: 10/18/2009] [Indexed: 02/03/2023]
Abstract
Parenteral long-acting lipophilic solutions have been used for decades and might in the future be used in the design of depots with tailored delivery characteristics. The present review highlights major factors influencing the in vivo performance of lipophilic solutions. Furthermore, an account is given of the characteristics of employed in vitro release methods with a focus on the "state" of sink condition, the stirring conditions, and the oil-water interfacial area. Finally, the capability of in vitro release data to predict the in vivo performance of drug substances administrated in the form of lipophilic solutions is discussed. It is suggested that as long as the major rate-limiting in vivo release mechanism is governed by the drug partitioning between the oil vehicle and the tissue fluid, the use of in vitro release testing in quality control appears to be realistic. With increasing lipophilicity of the drug substances and longer duration of action, the in vivo drug release process may become more complex. As discussed, practical analytical problems together with the inability of release methods to mimic two or more concomitant in vivo events may constitute severe impediments for establishment of in vitro in vivo correlations.
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Affiliation(s)
- Susan Weng Larsen
- Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100, Copenhagen, Denmark.
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Pedersen BT, Larsen SW, Østergaard J, Larsen C. In Vitro Assessment of Lidocaine Release from Aqueous and Oil Solutions and from Preformed and in Situ Formed Aqueous and Oil Suspensions. Parenteral Depots for Intra-Articular Administration. Drug Deliv 2008; 15:23-30. [DOI: 10.1080/10717540701828657] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Larsen SW, Jessen MNB, Østergaard J, Larsen C. Assessment of Drug Release from Oil Depot Formulations Using an In Vitro Model—Potential Applicability in Accelerated Release Testing. Drug Dev Ind Pharm 2008; 34:297-304. [DOI: 10.1080/03639040701655994] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Østergaard J, Jorgensen L, Engelbrecht Thomsen A, Weng Larsen S, Larsen C, Jensen H. Drug-liposome distribution phenomena studied by capillary electrophoresis-frontal analysis. Electrophoresis 2008; 29:3320-4. [DOI: 10.1002/elps.200700757] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Larsen SW, Frost AB, Østergaard J, Marcher H, Larsen C. On the mechanism of drug release from oil suspensions in vitro using local anesthetics as model drug compounds. Eur J Pharm Sci 2008; 34:37-44. [DOI: 10.1016/j.ejps.2008.02.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2007] [Revised: 01/24/2008] [Accepted: 02/13/2008] [Indexed: 10/22/2022]
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Larsen SW, Østergaard J, Friberg-Johansen H, Jessen MNB, Larsen C. In vitro assessment of drug release rates from oil depot formulations intended for intra-articular administration. Eur J Pharm Sci 2006; 29:348-54. [PMID: 16920337 DOI: 10.1016/j.ejps.2006.07.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2006] [Revised: 06/26/2006] [Accepted: 07/08/2006] [Indexed: 11/16/2022]
Abstract
In vitro drug release rates from oil depot formulations intended for intra-articular injection have been investigated by using the rotating dialysis cell. The rate of drug appearance in the acceptor phase after instillation of sesame oil solutions of naproxen and lidocaine into the small aqueous donor compartment applied to first-order kinetics. In the present three-compartment model oil-aqueous phase distribution equilibrium was maintained at all times in the donor phase and thus drug efflux from the donor compartment was dictated by the distribution coefficient. A mathematical description of the rate of drug release into the acceptor phase and the interdependence of the observed apparent first-order rate constants and the drug oil-water distribution coefficients is provided. The in vitro model may constitute a valuable tool in formulation design and development allowing comparison of drug release rates originating from alteration of the oil vehicle composition, the drug compound or the composition of the release media to be performed.
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Affiliation(s)
- Susan Weng Larsen
- Department of Pharmaceutics and Analytical Chemistry, The Danish University of Pharmaceutical Sciences, Universitetsparken 2, DK-2100 Copenhagen, Denmark.
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Pedersen BT, Ostergaard J, Larsen SW, Larsen C. Characterization of the rotating dialysis cell as an in vitro model potentially useful for simulation of the pharmacokinetic fate of intra-articularly administered drugs. Eur J Pharm Sci 2005; 25:73-9. [PMID: 15854803 DOI: 10.1016/j.ejps.2005.01.019] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2004] [Revised: 01/20/2005] [Accepted: 01/28/2005] [Indexed: 11/26/2022]
Abstract
The rotating dialysis cell consisting of a donor and an acceptor compartment with volumes of 10 and 1000 ml, respectively, separated by a dialysis membrane is proposed as an in vitro model potentially useful for simulation of the events influencing drug residence time in the knee joint cavity after intra-articular instillation. The purpose of this study was to characterize the rotating dialysis cell model with respect to basic model and drug related factors affecting the rate of drug appearance in the acceptor phase after initial instillation of the solutes into the donor cell. A total of 15 model compounds were included in the study and it was revealed that the transport processes were governed by (i) the volume of the donor solution and (ii) the molecular weight of the diffusants. A relationship between the donor volume-independent permeability coefficient and the molecular weight of the diffusants has been established. Additionally, the model was robust with release kinetics being insensitive to changes in pH, ionic strength, viscosity of the release medium, and revolution speed of the donor cell. The characteristics of the rotating dialysis cell model suggest that it may be a useful tool in the design of innovative depot injectables in the area of local joint delivery.
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Affiliation(s)
- Brian Thoning Pedersen
- Department of Pharmaceutics, The Danish University of Pharmaceutical Sciences, Universitetsparken 2, DK-2100 Copenhagen, Denmark
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Larsen SW, Ankersen M, Larsen C. Kinetics of degradation and oil solubility of ester prodrugs of a model dipeptide (Gly-Phe). Eur J Pharm Sci 2005; 22:399-408. [PMID: 15265509 DOI: 10.1016/j.ejps.2004.04.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2003] [Revised: 04/06/2004] [Accepted: 04/21/2004] [Indexed: 10/26/2022]
Abstract
Oil-based depot formulations may constitute a future delivery method for small peptides. Thus, a requirement is attainment of sufficient oil solubility for such active compounds. A model dipeptide (Gly-Phe) has been converted into lipophilic prodrugs by esterification at the C-terminal carboxylic acid group. The decomposition kinetics of octyl ester of Gly-Phe (IV) has been investigated at pH 7.4 (37 degrees C) and IV was shown to degrade by first-order kinetics via two parallel pathways (1) intramolecular aminolysis resulting in formation of a 2,5-diketopiperazine and (2) hydrolysis of the ester bond producing the dipeptide. The cyclisation reaction was dominating in the decomposition of methyl (II) butyl (III) octyl (IV) decyl (V) and dodecyl (VI) esters of Gly-Phe at pH 7.4. However, this degradation pathway was almost negligible for pH below 6. During degradation of the dipeptide esters in 80% human plasma pH 7.4 (37 degrees C) a minimal amount of cyclo(-Gly-Phe) was formed. A faster degradation of the esters in 80% human plasma pH 7.4 compared to those in aqueous solution pH 7.4 was suggested to be due to fast cleavage of the peptide bond. Low oil solubilities for Gly-Phe and the hydrochlorides of the dipeptide esters III and VI were observed. Although the solubility of Gly-Phe in oil solutions was enhanced by hydrophobic ion pairing with sodium decyl sulfonate the oil solubility was still less than 1 mg Gly-Phe/ml. By addition of a solubiliser, 10% N,N-dimethylacetamide (DMA), to Viscoleo the solubility of the HIP complexes increased significantly. The present study indicates that sufficient oil solubility might only be obtained for relatively small peptides by using the prodrug approach in combination with solubility enhancing organic solvents like DMA.
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Affiliation(s)
- Susan Weng Larsen
- Department of Pharmaceutics, The Danish University of Pharmaceutical Sciences, Universitetsparken 2, DK-2100 Copenhagen, Denmark.
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Larsen SW, Sidenius M, Ankersen M, Larsen C. Kinetics of degradation of 4-imidazolidinone prodrug types obtained from reacting prilocaine with formaldehyde and acetaldehyde. Eur J Pharm Sci 2004; 20:233-40. [PMID: 14550890 DOI: 10.1016/s0928-0987(03)00198-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The kinetics of decomposition of 4-imidazolidinone prodrug types obtained by reacting prilocaine (I) with formaldehyde and acetaldehyde has been studied in aqueous solution in the pH range 1-7.4 at 60 and 37 degrees C, respectively. At pH<5 the hydrolysis of the derivative derived from formaldehyde (II) to yield I obeyed apparent first-order kinetics. At higher pH, the decomposition reactions proceeded to an equilibrium and the reactions could be described by first- and second-order reversible kinetics. A plot of the logarithm of the apparent first-order rate constants for hydrolysis of II against pH resulted in a sigmoidal-shaped pH-rate profile characteristic for the hydrolysis of many N-Mannich bases. A half-life at pH 7.4 (60 degrees C) of 6.9h for compound II was calculated. Compared to II the 4-imidazolidinone derived from acetaldehyde (III) exhibited enhanced instability in aqueous buffer solutions. The decomposition was followed at 37 degrees C monitoring the decrease in concentration of intact (III). At acidic pH the reactions displayed strict first-order kinetics and the disappearance of III was accompanied by a concomitant formation of I. At pH 7.4, the rate data also applied reasonably well to first-order kinetics despite the observation that small amounts of III was formed at pH 7.4 from a solution containing equimolar concentrations of acetaldehyde and prilocaine (10(-4)M). In case of III, a bell-shaped pH-rate profile was obtained by plotting the logarithm of the pseudo-first-order rate constants against pH indicating the involvement of a kinetically significant intermediate in the reaction pathway and a change of the rate-limiting step in the overall reaction with pH. For the stability studies performed at pH 6.9 and 7.4 product analysis revealed that parallel to formation of (I) an unknown compound (X) emerged. Compared to III, compound X is hydrolysed to give I at a slower rate (t(50%)=30 h at 37 degrees C). Based on LC-MS data it is suggested that (X) is an isomeric form of III, which may exist in four diastereomeric forms. Thus, at physiological pH an initial relatively fast regeneration of I from III is to be expected followed by a slower drug activation resulting from hydrolysis of the isomeric form of III.
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Affiliation(s)
- Susan Weng Larsen
- Department of Pharmaceutics, The Danish University of Pharmaceutical Sciences, Universitetsparken 2, DK-2100 Copenhagen, Denmark
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Larsen SW, Rinvar E, Svendsen O, Lykkesfeldt J, Friis GJ, Larsen C. Determination of the disappearance rate of iodine-125 labelled oils from the injection site after intramuscular and subcutaneous administration to pigs. Int J Pharm 2001; 230:67-75. [PMID: 11672957 DOI: 10.1016/s0378-5173(01)00860-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The rate of disappearance of clinically used vegetable oils, Viscoleo, sesame oil, castor oil and isopropyl myristate, from the injection site after intramuscular (i.m.) or subcutaneous (s.c.) administration to pigs were determined by using a non-invasive gamma-scintigraphy method. All the oil vehicles were spiked with 2.5% (v/v) (125)I-triolein and six injections of 1.9 ml were given to each of 12 pigs. No significant difference (ANOVA) in disappearance rate of each individual oil vehicle from the different injection sites was observed after administration of the oils: i.m. in the lower back, s.c. in the neck and s.c. in the mid-back. Likewise, no inter-individual difference between the pigs was observed. The half-life of 14 days for Viscoleo was significantly smaller than those of the other oil vehicles (P<0.0001), i.e. 23,20,20 days for sesame oil, castor oil and isopropyl myristate, respectively. Due to the spreading effect of the oils and reflux of the oils through the injection canal, the half-lives were calculated omitting the data for the first sampling day.
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Affiliation(s)
- S W Larsen
- Department of Analytical and Pharmaceutical Chemistry, The Royal Danish School of Pharmacy, Universitetsparken 2, DK-2100, Copenhagen, Denmark.
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