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Sabaté-Martínez C, Paulsson M, González-Suárez S, Elofsson U, Fureby AM, Wahlgren M, López-Cabezas C. How are we handling protein drugs in hospitals? A human factors and systems engineering approach to compare two hospitals and suggest a best practice. Int J Qual Health Care 2024; 36:mzae020. [PMID: 38462489 PMCID: PMC11002458 DOI: 10.1093/intqhc/mzae020] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 02/13/2024] [Accepted: 03/07/2024] [Indexed: 03/12/2024] Open
Abstract
Biopharmaceuticals are complex biological molecules that require careful storage and handling to ensure medication integrity. In this study, a work system analysis of real-world protein drug (PD) handling was performed with the following goals: identify main barriers and facilitators for successful adherence to accepted recommendations in PD handling, analyse differences in two organizations, and define a Best Current Practice in the real-life handling of PDs based on the results of the work system analysis. Observational study was held in two university hospitals in Spain and Sweden. Based on the Systems Engineering Initiative for Patient Safety (SEIPS) model, the tools chosen were: the PETT scan, in order to indicate the presence of barriers or facilitators for the PETT components (People, Environment, Tools, Tasks); the Tasks and tools matrices to construct a checklist to record direct observations during the real-life handling of biopharmaceuticals, and the Journey map to depict the work process. Observations were performed between March and November 2022. Each episode of direct observation included a single protein drug in some point of the supply chain and considered all the elements in the work system. Based on the results of the work system analysis and the literature review, the authors propose a list of items which could be assumed as Best Current Practice for PDs handling in hospitals. There were a total of 34 observations involving 19 PDs. Regarding People involved in the work process, there was a diversity of professionals with different previous training and knowledge, leading to an information gap. With respect to Environment, some structural and organizational differences between hospitals lead to risks related to the time exposure of PDs to room temperature and mechanical stress. Some differences also existed in the Tools and Tasks involved in the process, being especially relevant to the lack of compatibility information of PDs with new technologies, such as pneumatic tube system, robotic reconstitution, or closed-system transfer devices. Finally, 15 suggestions for best current practice are proposed. Main barriers found for compliance with accepted recommendations were related to the information gap detected in professionals involved in the handling of protein drugs, unmonitored temperature, and the lack of compatibility information of protein drugs with some new technologies. By applying a Human Factors and Systems Engineering Approach, the comparison of two European hospitals has led to a suggested list of Best Current Practices in the handling of protein drugs in a hospital.
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Affiliation(s)
- Clàudia Sabaté-Martínez
- Department of Women’s and Children’s Health, Uppsala University, Akademiska sjukhuset, Entrance 95/96, Uppsala 751 85, Sweden
- Faculty of Pharmacy and Food Science, University of Barcelona, c/Joan XXIII, 27-31, Barcelona 08028, Spain
| | - Mattias Paulsson
- Department of Women’s and Children’s Health, Uppsala University, Akademiska sjukhuset, Entrance 95/96, Uppsala 751 85, Sweden
| | | | - Ulla Elofsson
- RISE Research Institute of Sweden, AB, Box 857, 501 15, Borås, Stockholm 11428, Sweden
| | - Anna Millqvist Fureby
- RISE Research Institute of Sweden, AB, Box 857, 501 15, Borås, Stockholm 11428, Sweden
| | - Marie Wahlgren
- Department of Food Technology, Lund University, P.O. Box 124, Lund 22100, Sweden
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Martínez CS, Amery L, De Paoli G, Elofsson U, Fureby AM, Kwok S, López-Cabezas C, Rosenberger M, Schoenau C, Wahlgren M, Paulsson M. Examination of the Protein Drug Supply Chain in a Swedish University Hospital: Focus on Handling Risks and Mitigation Measures. J Pharm Sci 2023; 112:2799-2810. [PMID: 37160226 DOI: 10.1016/j.xphs.2023.05.003] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 05/01/2023] [Accepted: 05/01/2023] [Indexed: 05/11/2023]
Abstract
Protein drugs, such as monoclonal antibodies, have proved successful in treating cancer and immune system diseases. The structural complexity of these molecules requires careful handling to ensure integrity and stability of the drug. In this study, a failure mode and effects analysis was performed based on a Gemba Walk method in a Swedish University Hospital. The Gemba Walk is focused on pharmacists observing the actual supply process steps from distributor, pharmacy cleanroom to patient administration. Relevant protein drugs are chosen based on sales statistics within the hospital and the corresponding wards were observed. Further is the Double Diamond design method used to identify major risks and deliver mitigation strategies. The study identified potential stress factors such as temperature, shock by impact, shaking, vibration and light exposure. There were also risks associated with porters' and healthcare professionals' lack of awareness and access to information. These risk factors may cause loss of efficacy and quality of the protein drug, potentially leading to patient safety concerns. In this study, a simulation is also performed to list measures that theoretically should be in place to ensure the quality of the protein drug, for example validated and protocol-based compounding in cleanroom, training and validated transports.
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Affiliation(s)
- Clàudia Sabaté Martínez
- Department of Women's and Children's Health, Uppsala University, Akademiska sjukhuset, SE-751 85 Uppsala, Sweden; Faculty of Pharmacy and Food Science, University of Barcelona, Spain
| | - Leanne Amery
- Late Stage Formulation Sciences, BioPharmaceuticals Development, Dosage Form Design & Development, AstraZeneca, Granta Park, Cambridge, UK
| | - Giorgia De Paoli
- MEMO Research, Division of Molecular and Clinical Medicine, School of Medicine, University of Dundee, Ninewells Hospital, Dundee, UK
| | - Ulla Elofsson
- RISE Research Institute of Sweden, Stockholm, Sweden
| | | | - Stanley Kwok
- Late Stage Formulation Sciences, BioPharmaceuticals Development, Dosage Form Design & Development, AstraZeneca, One MedImmune Way, Gaithersburg, MD 20878, USA
| | | | - Marika Rosenberger
- Sanofi-Aventis Deutschland GmbH, Biologics Drug Product Development & Manufacturing, Industriepark Hoechst, K703. Brüningstr. 50, 65926 Frankfurt am Main, Germany
| | - Christian Schoenau
- Sanofi-Aventis Deutschland GmbH, Biologics Drug Product Development & Manufacturing, Industriepark Hoechst, K703. Brüningstr. 50, 65926 Frankfurt am Main, Germany
| | - Marie Wahlgren
- Department of Food Technology, Lund University, P.O. Box 124, 22100 Lund, Sweden
| | - Mattias Paulsson
- Department of Women's and Children's Health, Uppsala University, Akademiska sjukhuset, SE-751 85 Uppsala, Sweden.
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Bolinsson H, Söderberg C, Herranz-Trillo F, Wahlgren M, Nilsson L. Realizing the AF4-UV-SAXS on-line coupling on protein and antibodies using high flux synchrotron radiation at the CoSAXS beamline, MAX IV. Anal Bioanal Chem 2023; 415:6237-6246. [PMID: 37572213 PMCID: PMC10558385 DOI: 10.1007/s00216-023-04900-7] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 07/31/2023] [Accepted: 08/02/2023] [Indexed: 08/14/2023]
Abstract
In this paper, we demonstrate the coupling of synchrotron small angle X-ray scattering (SAXS) to asymmetrical flow-field flow fractionation (AF4) for protein characterization. To the best of our knowledge, this is the first time AF4 is successfully coupled to a synchrotron for on-line measurements on proteins. This coupling has potentially high impact, as it opens the possibility to characterize individual constituents of sensitive and/or complex samples, not suited for separation using other techniques, and for low electron density samples where high X-ray flux is required, e.g., biomolecules and biologics. AF4 fractionates complex samples in native or close to native environment, with low shear forces and system surface area. Many orders of magnitude in size can be fractionated in one measurement, without having to reconfigure the experimental setup. We report AF4 fractionations with correlated UV and statistically adequate SAXS data of bovine serum albumin and a monoclonal antibody and evaluate SAXS data recorded for the two protein systems.
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Affiliation(s)
- Hans Bolinsson
- Department of Food Technology, Engineering and Nutrition, Lund University, Lund, Sweden.
| | - Christopher Söderberg
- RISE Research Institutes of Sweden, Division Bioeconomy and Health, Chemical Process and Pharmaceutical Development, Lund, Sweden
| | | | - Marie Wahlgren
- Department of Food Technology, Engineering and Nutrition, Lund University, Lund, Sweden
| | - Lars Nilsson
- Department of Food Technology, Engineering and Nutrition, Lund University, Lund, Sweden
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Västberg A, Bolinsson H, Leeman M, Nilsson L, Nylander T, Sejwal K, Sintorn IM, Lidayova K, Sjögren H, Wahlgren M, Elofsson U. Investigating Thermally Induced Aggregation of Somatropin- New Insights Using Orthogonal Techniques. Int J Pharm 2023; 637:122829. [PMID: 36948472 DOI: 10.1016/j.ijpharm.2023.122829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 02/24/2023] [Accepted: 03/09/2023] [Indexed: 03/24/2023]
Abstract
Three orthogonal techniques were used to provide new insights into thermally induced aggregation of the therapeutic protein Somatropin at pH 5.8 and 7.0. The techniques were Dynamic Light Scattering (DLS), Asymmetric Flow-Field Flow-Fractionation (AF4), and the TEM-based analysis system MiniTEM™. In addition, Differential Scanning Calorimetry (DSC) was used to study the thermal unfolding and stability. DSC and DLS were used to explain the initial aggregation process and aggregation rate at the two pH values. The results suggest that electrostatic stabilization seems to be the main reason for the faster initial aggregation at pH 5.8, i.e., closer to the isoelectric point of Somatropin. AF4 and MiniTEM were used to investigate the aggregation pathway further. Combining the results allowed us to demonstrate Somatropin's thermal aggregation pathway at pH 7.0. The growth of the aggregates appears to follow two steps. Smaller elongated aggregates are formed in the first step, possibly initiated by partly unfolded species. In the second step, occurring during longer heating, the smaller aggregates assemble into larger aggregates with more complex structures.
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Affiliation(s)
- Amanda Västberg
- Research Institutes of Sweden, Drottning Kristinas väg 61B, 11428 Stockholm, Sweden; Department of Food Technology, Engineering and Nutrition, Faculty of Engineering LTH, Lund University, Lund, Sweden
| | - Hans Bolinsson
- Department of Food Technology, Engineering and Nutrition, Faculty of Engineering LTH, Lund University, Lund, Sweden
| | | | - Lars Nilsson
- Department of Food Technology, Engineering and Nutrition, Faculty of Engineering LTH, Lund University, Lund, Sweden
| | - Tommy Nylander
- Physical Chemistry, Department of Chemistry, Lund University, Lund, Sweden
| | | | | | | | | | - Marie Wahlgren
- Department of Food Technology, Engineering and Nutrition, Faculty of Engineering LTH, Lund University, Lund, Sweden
| | - Ulla Elofsson
- Research Institutes of Sweden, Drottning Kristinas väg 61B, 11428 Stockholm, Sweden
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Gidlöf Z, Pedersen BL, Nilsson L, Teleman A, Wahlgren M, Millqvist-Fureby A. Utilising phase diagram to understand barley starch microsphere preparation in an aqueous two-phase system. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.130652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Palmkron SB, Bergenståhl B, Håkansson S, Wahlgren M, Fureby AM, Larsson E. Quantification of structures in freeze-dried materials using X-ray microtomography. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.130726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
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Fuentes C, Choi J, Wahlgren M, Nilsson L. Charge and zeta-potential distribution in starch modified with octenyl succininc anhydride (OSA) determined using electrical asymmetrical flow field-flow fractionation (EAF4). Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.130570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Sanchez-Fernandez A, Larsson J, Leung AE, Holmqvist P, Czakkel O, Nylander T, Ulvenlund S, Wahlgren M. Topological Dynamics of Micelles Formed by Geometrically Varied Surfactants. Langmuir 2022; 38:10075-10080. [PMID: 35914231 PMCID: PMC9404537 DOI: 10.1021/acs.langmuir.2c00230] [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] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 07/19/2022] [Indexed: 06/15/2023]
Abstract
The molecular architecture of sugar-based surfactants strongly affects their self-assembled structure, i.e., the type of micelles they form, which in turn controls both the dynamics and rheological properties of the system. Here, we report the segmental and mesoscopic structure and dynamics of a series of C16 maltosides with differences in the anomeric configuration and degree of tail unsaturation. Neutron spin-echo measurements showed that the segmental dynamics can be modeled as a one-dimensional array of segments where the dynamics increase with inefficient monomer packing. The network dynamics as characterized by dynamic light scattering show different relaxation modes that can be associated with the micelle structure. Hindered dynamics are observed for arrested networks of worm-like micelles, connected to their shear-thinning rheology, while nonentangled diffusing rods relate to Newtonian rheological behavior. While the design of novel surfactants with controlled properties poses a challenge for synthetic chemistry, we demonstrate how simple variations in the monomer structure can significantly influence the behavior of surfactants.
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Affiliation(s)
| | - Johan Larsson
- Biofilms
Research Center for Biointerfaces and Department of Biomedical Science,
Faculty of Health and Society, Malmö
University, Per Albin
Hanssons Väg 35, 21432 Malmö, Sweden
| | - Anna E. Leung
- European
Spallation Source ERIC, P.O. Box 176, 221 00 Lund, Sweden
| | - Peter Holmqvist
- Physical
Chemistry, Department of Chemistry, Lund
University, Box 124, 221
00 Lund, Sweden
| | - Orsolya Czakkel
- Institute
Laue-Langevin, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - Tommy Nylander
- Physical
Chemistry, Department of Chemistry, Lund
University, Box 124, 221
00 Lund, Sweden
| | | | - Marie Wahlgren
- Food
Technology, Engineering and Nutrition, Lund
University, Box 124, 221 00 Lund, Sweden
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9
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Palmkron SB, Gustavsson L, Wahlgren M, Bergensthål B, Fureby AM. Temperature and Heat Transfer Control During Freeze Drying. Effect of Vial Holders and Influence of Pressure. Pharm Res 2022; 39:2597-2606. [PMID: 35925479 PMCID: PMC9556401 DOI: 10.1007/s11095-022-03353-4] [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] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 07/26/2022] [Indexed: 11/25/2022]
Abstract
Objective A common issue of freeze drying is the inhomogeneity between samples, both in regards to water content and structure. The purpose of this study is to address this issue, and try to understand the cause of inhomogeneity in the heat transfer and sample temperature. Methods The temperature and the heat transfer was measured using different setups, both with and without vial holders at various positions at different shelf temperature and chamber pressures. By comparing sublimation rate measurements (water sample) with temperature equilibrium measurements with a non-evaporating liquid (oil sample), the heat transfer contribution from radiation and conduction could be separated and investigated individually. Results The oil sample temperature increases each time the pressure is decreased; the increase is highest at lower shelf temperatures. Using vial holder reduces the deviation between the samples but have limited effect on the temperature increase. The sublimation rate for water sample is pressure dependent and samples close to the walls have a higher sublimation rate than vials in the center. The sublimation rate increases slightly when using a vial holder but the deviation between vials becomes more random. Conclusions The heat transfer consists of conduction through rectified vapor and radiation from surrounding walls, about 65–75% of the heat is transferred by conduction and 25–35% by radiation under normal operational conditions. As the vial holder is also influenced by the radiation, the vial inside the holder is indirectly affected by the surrounding radiation. Supplementary Information The online version contains supplementary material available at 10.1007/s11095-022-03353-4.
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Affiliation(s)
- Shuai Bai Palmkron
- Department of Food Technology, Engineering and Nutrition, Lunds Universitet, Institutionen För Livsmedelsteknik, Box 124, 221 00, Lund, Sweden.
| | - Linnea Gustavsson
- Department of Food Technology, Engineering and Nutrition, Lunds Universitet, Institutionen För Livsmedelsteknik, Box 124, 221 00, Lund, Sweden
- Chemical Process and Pharmaceutical Development, RISE, 114 28, Stockholm, Sweden
| | - Marie Wahlgren
- Department of Food Technology, Engineering and Nutrition, Lunds Universitet, Institutionen För Livsmedelsteknik, Box 124, 221 00, Lund, Sweden
| | - Björn Bergensthål
- Department of Food Technology, Engineering and Nutrition, Lunds Universitet, Institutionen För Livsmedelsteknik, Box 124, 221 00, Lund, Sweden
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Zhang L, Wahlgren M, Bergenståhl B. Oil-Based Delivery Control Release System Targeted to the Later Part of the Gastrointestinal Tract-A Mechanistic Study. Pharmaceutics 2022; 14:pharmaceutics14050896. [PMID: 35631482 PMCID: PMC9144740 DOI: 10.3390/pharmaceutics14050896] [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: 03/08/2022] [Revised: 04/07/2022] [Accepted: 04/18/2022] [Indexed: 02/01/2023] Open
Abstract
Oil-based drug delivery systems have been studied in different aspects. The present study proposes a new application for an oil-based delivery system, focusing on controlled release until the drug reaches the later part of the small intestine. Bulk surfactants and interfacial surfactants were added into the oil formulation to provide a better mechanistic understating of the lipolysis. Validation of the modified in vitro method shows the overall conversion from medium-chain triglyceride oil (MCT oil) to free fatty acids (FFA) of 100 ± 4% in five replicates. This fully converted level and high reproducibility are fundamental for the following investigations where any retarding effect can be distinguished from the experimental errors. The results show that viscosity and thermodynamic activity have limited retardation. Furthermore, the former may change the kinetics of lipolysis, while the latter changes the equilibrium level. The gel-forming retarder (ethylcellulose) displayed a strong effect. Whereas the lipolysis was significantly retarded (>50%) when the retarders altered the interfacial composition (poloxamer 407), degradable interfacial surfactants did not have the same effect. However, surface-active, lipolysis-resistant retarders with a high CMC did not show a retarding effect.
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Hjalte J, Hossain S, Hugerth A, Sjögren H, Wahlgren M, Larsson P, Lundberg D. Aggregation Behavior of Structurally Similar Therapeutic Peptides Investigated by 1H NMR and All-Atom Molecular Dynamics Simulations. Mol Pharm 2022; 19:904-917. [PMID: 35104408 PMCID: PMC8905580 DOI: 10.1021/acs.molpharmaceut.1c00883] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [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] [Indexed: 11/30/2022]
Abstract
Understanding of peptide aggregation propensity is an important aspect in pharmaceutical development of peptide drugs. In this work, methodologies based on all-atom molecular dynamics (AA-MD) simulations and 1H NMR (in neat H2O) were evaluated as tools for identification and investigation of peptide aggregation. A series of structurally similar, pharmaceutically relevant peptides with known differences in aggregation behavior (D-Phe6-GnRH, ozarelix, cetrorelix, and degarelix) were investigated. The 1H NMR methodology was used to systematically investigate variations in aggregation with peptide concentration and time. Results show that 1H NMR can be used to detect the presence of coexisting classes of aggregates and the inclusion or exclusion of counterions in peptide aggregates. Interestingly, results suggest that the acetate counterions are included in aggregates of ozarelix and cetrorelix but not in aggregates of degarelix. The peptides investigated in AA-MD simulations (D-Phe6-GnRH, ozarelix, and cetrorelix) showed the same rank order of aggregation propensity as in the NMR experiments. The AA-MD simulations also provided molecular-level insights into aggregation dynamics, aggregation pathways, and the influence of different structural elements on peptide aggregation propensity and intermolecular interactions within the aggregates. Taken together, the findings from this study illustrate that 1H NMR and AA-MD simulations can be useful, complementary tools in early evaluation of aggregation propensity and formulation development for peptide drugs.
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Affiliation(s)
- Johanna Hjalte
- Food Technology, Engineering and Nutrition, Lund University, Box 124, 221 00 Lund, Sweden
| | - Shakhawath Hossain
- Department of Pharmacy, Drug Delivery, Uppsala University, Box 580, 751 23 Uppsala, Sweden
| | - Andreas Hugerth
- Ferring Pharmaceuticals A/S, Amager Strandvej 405, 2770 Kastrup, Denmark
| | - Helen Sjögren
- Ferring Pharmaceuticals A/S, Amager Strandvej 405, 2770 Kastrup, Denmark
| | - Marie Wahlgren
- Food Technology, Engineering and Nutrition, Lund University, Box 124, 221 00 Lund, Sweden
| | - Per Larsson
- Department of Pharmacy, Drug Delivery, Uppsala University, Box 580, 751 23 Uppsala, Sweden
| | - Dan Lundberg
- CR Competence AB, Center for Chemistry and Chemical Engineering, Box 124, 221 00 Lund, Sweden
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Ali A, Ringstad L, Skedung L, Falkman P, Wahlgren M, Engblom J. Tactile friction of topical creams and emulsions: Friction measurements on excised skin and VitroSkin® using ForceBoard™. Int J Pharm 2022; 615:121502. [DOI: 10.1016/j.ijpharm.2022.121502] [Citation(s) in RCA: 1] [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: 08/27/2021] [Revised: 01/13/2022] [Accepted: 01/19/2022] [Indexed: 11/17/2022]
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Ali A, Skedung L, Burleigh S, Lavant E, Ringstad L, Anderson CD, Wahlgren M, Engblom J. Relationship between sensorial and physical characteristics of topical creams: A comparative study on effects of excipients. Int J Pharm 2021; 613:121370. [PMID: 34952146 DOI: 10.1016/j.ijpharm.2021.121370] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [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: 08/27/2021] [Revised: 11/27/2021] [Accepted: 12/07/2021] [Indexed: 01/27/2023]
Abstract
Rising consumer demands for safer, more natural, and sustainable topical products have led to increased interest in finding alternative excipients, while retaining functionality and cosmetic appeal. Particle-stabilized Pickering creams have emerged as possible alternatives to replace traditional surfactant-stabilized creams and are thus one of the focuses in this study. The aim of this paper was to study relationships between sensorial characteristics and physical properties to understand how different excipients affect these aspects, comparing one starch particle-stabilized and three surfactant-stabilized formulations. A human panel was used to evaluate sensorial perception, while physical properties were deduced by rheology and tactile friction, together with in vivo and ex vivo skin hydration measurements. The results show that sensorial attributes related to the application phase can be predicted with rheology, while afterfeel attributes can be predicted with tactile friction studies. Differences in rheological and sensory properties among surfactant-based creams could mainly be attributed to the type of emollients used, presence of thickeners and surfactant composition. Differences between surfactant-based creams and a Pickering cream were more evident in relation to the afterfeel perception. Presence of starch particles in the residual film on skin results in high tactile friction and low perception of residual coating, stickiness, greasiness, and slipperiness in sensorial afterfeel.
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Affiliation(s)
- A Ali
- Biomedical Sciences, Faculty of Health and Society, Malmö University, SE-205 06 Malmö, Sweden; Biofilms - Research Center for Biointerfaces, Malmö University, SE-205 06 Malmö, Sweden; Speximo AB, Medicon Village, SE-223 81 Lund, Sweden.
| | - L Skedung
- RISE Research Institutes of Sweden, Bioeconomy and Health, Perception and Design, SE-114 28 Stockholm, Sweden
| | - S Burleigh
- Food Technology, Engineering and Nutrition, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
| | - E Lavant
- Biomedical Sciences, Faculty of Health and Society, Malmö University, SE-205 06 Malmö, Sweden; Biofilms - Research Center for Biointerfaces, Malmö University, SE-205 06 Malmö, Sweden
| | - L Ringstad
- RISE Research Institutes of Sweden, Bioeconomy and Health, Perception and Design, SE-114 28 Stockholm, Sweden
| | - C D Anderson
- Department of Biomedical and Clinical Sciences, Linköping University, SE-581 83 Linköping, Sweden
| | - M Wahlgren
- Food Technology, Engineering and Nutrition, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
| | - J Engblom
- Biomedical Sciences, Faculty of Health and Society, Malmö University, SE-205 06 Malmö, Sweden; Biofilms - Research Center for Biointerfaces, Malmö University, SE-205 06 Malmö, Sweden
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14
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Larsson J, Williams AP, Wahlgren M, Porcar L, Ulvenlund S, Nylander T, Tabor RF, Sanchez-Fernandez A. Shear-induced nanostructural changes in micelles formed by sugar-based surfactants with varied anomeric configuration. J Colloid Interface Sci 2021; 606:328-336. [PMID: 34392029 DOI: 10.1016/j.jcis.2021.08.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [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: 06/26/2021] [Revised: 07/13/2021] [Accepted: 08/01/2021] [Indexed: 11/17/2022]
Abstract
HYPOTHESIS The self-assembly of long tail sugar-based surfactants into worm-like micelles has recently been demonstrated, and the rheological properties of such systems have been shown to be tuneable through subtle modifications of the molecular characteristics of the surfactant monomer. In particular, the anomeric configuration of the hexadecylmaltoside headgroup was shown to induce profound changes in the nanostructure and rheology of the system. The origin of such changes is hypothesised to arise from differences in the structure and relaxation of the micellar networks in the semi-dilute regime. EXPERIMENTS Here we explore the molecular background to the flow properties of the two anomers of hexadecylmaltoside (α- and β-C16G2) by directly connecting their rheological behaviour to the micelle morphology. For this purpose, 1-3 plane rheo-small-angle neutron scattering measurements, using a Couette cell geometry, probed the structural changes in the micellar phase under shear. The effect of surfactant anomeric configuration, surfactant concentration, temperature and mixing ratio of the two anomers were investigated. The static micelle structure in the semi-dilute regime was determined using the polymer reference interaction site model. FINDINGS The segmental alignment of the micellar phase was studied under several flow conditions, showing that the shear-thinning behaviour relates to the re-arrangement of β-C16G2 worm-like micelles, whilst shorter α-C16G2 micelles are considerably less affected by the flow. The results are rationalised in terms of micelle alignment and disruption of the entangled network, providing a detailed mechanism by which sugar-based surfactants control the rheology of the fluid. To further enable future studies, we provide the complete code for modelling micelle structure in the semi-dilute regime using the polymer reference interaction site model.
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Affiliation(s)
- Johan Larsson
- Physical Chemistry, Department Chemistry, Lund University, Box 124, Lund 221 00, Sweden
| | - Ashley P Williams
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia
| | - Marie Wahlgren
- Food Technology, Nutrition and Engineering, Lund University, Box 124, Lund 221 00, Sweden; Enza Biotech AB, Scheelevägen 22, Lund 22363, Sweden
| | - Lionel Porcar
- Institut Laue-Langevin, DS / LSS, 71 avenue des Martyrs, Grenoble 38000, France
| | - Stefan Ulvenlund
- Food Technology, Nutrition and Engineering, Lund University, Box 124, Lund 221 00, Sweden; Enza Biotech AB, Scheelevägen 22, Lund 22363, Sweden
| | - Tommy Nylander
- Physical Chemistry, Department Chemistry, Lund University, Box 124, Lund 221 00, Sweden; NanoLund, Lund University, Lund, Sweden
| | - Rico F Tabor
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia
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Larsson J, Leung AE, Lang C, Wu B, Wahlgren M, Nylander T, Ulvenlund S, Sanchez-Fernandez A. Tail unsaturation tailors the thermodynamics and rheology of a self-assembled sugar-based surfactant. J Colloid Interface Sci 2021; 585:178-183. [DOI: 10.1016/j.jcis.2020.11.063] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 11/16/2020] [Accepted: 11/17/2020] [Indexed: 10/22/2022]
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16
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Larsson J, Sanchez-Fernandez A, Leung AE, Schweins R, Wu B, Nylander T, Ulvenlund S, Wahlgren M. Molecular structure of maltoside surfactants controls micelle formation and rheological behavior. J Colloid Interface Sci 2021; 581:895-904. [DOI: 10.1016/j.jcis.2020.08.116] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 08/27/2020] [Accepted: 08/28/2020] [Indexed: 12/11/2022]
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Choi J, Wahlgren M, Ek V, Elofsson U, Fransson J, Nilsson L, Terry A, Söderberg CAG. Characterization of binding between model protein GA-Z and human serum albumin using asymmetrical flow field-flow fractionation and small angle X-ray scattering. PLoS One 2020; 15:e0242605. [PMID: 33232370 PMCID: PMC7685474 DOI: 10.1371/journal.pone.0242605] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 11/06/2020] [Indexed: 01/01/2023] Open
Abstract
Protein-based drugs often require targeted drug delivery for optimal therapy. A successful strategy to increase the circulation time of the protein in the blood is to link the therapeutic protein with an albumin-binding domain. In this work, we characterized such a protein-based drug, GA-Z. Using asymmetrical flow field-flow fractionation coupled with multi-angle light scattering (AF4-MALS) we investigated the GA-Z monomer-dimer equilibrium as well as the molar binding ratio of GA-Z to HSA. Using small angle X-ray scattering, we studied the structure of GA-Z as well as the complex between GA-Z and HSA. The results show that GA-Z is predominantly dimeric in solution at pH 7 and that it binds to monomeric as well as dimeric HSA. Furthermore, GA-Z binds to HSA both as a monomer and a dimer, and thus, it can be expected to stay bound also upon dilution following injection in the blood stream. The results from SAXS and binding studies indicate that the GA-Z dimer is formed between two target domains (Z-domains). The results also indicate that the binding of GA-Z to HSA does not affect the ratio between HSA dimers and monomers, and that no higher order oligomers of the complex are seen other than those containing dimers of GA-Z and dimers of HSA.
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Affiliation(s)
- Jaeyeong Choi
- Food Technology, Engineering and Nutrition, Faculty of Engineering LTH, Lund University, Lund, Sweden
| | - Marie Wahlgren
- Food Technology, Engineering and Nutrition, Faculty of Engineering LTH, Lund University, Lund, Sweden
| | - Vilhelm Ek
- Swedish Orphan Biovitrum AB (Sobi), Stockholm, Sweden
| | - Ulla Elofsson
- Division of Bioscience and Materials, RISE Research Institutes of Sweden, Lund, Sweden
| | | | - Lars Nilsson
- Food Technology, Engineering and Nutrition, Faculty of Engineering LTH, Lund University, Lund, Sweden
| | - Ann Terry
- MAX IV Laboratory, Lund University, Lund, Sweden
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Sanchez-Fernandez A, Diehl C, Houston JE, Leung AE, Tellam JP, Rogers SE, Prevost S, Ulvenlund S, Sjögren H, Wahlgren M. An integrative toolbox to unlock the structure and dynamics of protein-surfactant complexes. Nanoscale Adv 2020; 2:4011-4023. [PMID: 36132802 PMCID: PMC9417085 DOI: 10.1039/d0na00194e] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Accepted: 07/11/2020] [Indexed: 05/06/2023]
Abstract
The interactions between protein and surfactants play an important role in the stability and performance of formulated products. Due to the high complexity of such interactions, multi-technique approaches are required to study these systems. Here, an integrative approach is used to investigate the various interactions in a model system composed of human growth hormone and sodium dodecyl sulfate. Contrast variation small-angle neutron scattering was used to obtain information on the structure of the protein, surfactant aggregates and surfactant-protein complexes. 1H and 1H-13C HSQC nuclear magnetic resonance spectroscopy was employed to probe the local structure and dynamics of specific amino acids upon surfactant addition. Through the combination of these advanced methods with fluorescence spectroscopy, circular dichroism and isothermal titration calorimetry, it was possible to identify the interaction mechanisms between the surfactant and the protein in the pre- and post-micellar regimes, and interconnect the results from different techniques. As such, the protein was revealed to evolve from a partially unfolded conformation at low SDS concentration to a molten globule at intermediate concentrations, where the protein conformation and local dynamics of hydrophobic amino acids are partially affected compared to the native state. At higher surfactant concentrations the local structure of the protein appears disrupted, and a decorated micelle structure is observed, where the protein is wrapped around a surfactant assembly. Importantly, this integrative approach allows for the identification of the characteristic fingerprints of complex transitions as seen by each technique, and establishes a methodology for an in-detail study of surfactant-protein systems.
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Affiliation(s)
| | - Carl Diehl
- SARomics Biostructures AB Medicon Village, Scheelevägen 2 223 81 Lund Sweden
| | | | - Anna E Leung
- European Spallation Source Box 176 221 00 Lund Sweden
| | - James P Tellam
- ISIS Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory Didcot OX11 0QX UK
| | - Sarah E Rogers
- ISIS Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory Didcot OX11 0QX UK
| | - Sylvain Prevost
- Institut Laue-Langevin 71 Avenue des Martyrs 38000 Grenoble France
| | - Stefan Ulvenlund
- Food Technology, Engineering and Nutrition, Lund University Box 124 221 00 Lund Sweden
- EnzaBiotech AB Scheelevägen 22 223 63 Lund Sweden
| | - Helen Sjögren
- Ferring Pharmaceuticals A/S Kay Fiskers Plads 11 2300 Copenhagen S Denmark
| | - Marie Wahlgren
- Food Technology, Engineering and Nutrition, Lund University Box 124 221 00 Lund Sweden
- EnzaBiotech AB Scheelevägen 22 223 63 Lund Sweden
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Abstract
Formulations for nasal drug delivery often rely on water sorption to adhere to the mucosa, which also causes a higher water gradient over the tissue and subsequent dehydration. The primary aim of this study was therefore to evaluate mucosal response to dehydration and resolve the hypothesis that mucoadhesion achieved through water sorption could also be a constraint for drug absorption via the nasal route. The effect of altering water activity of the vehicle on Xylometazoline HCl and 51Cr-EDTA uptake was studied separately ex vivo using flow through diffusion cells and excised porcine mucosa. We have shown that a modest increase in the water gradient over mucosa induces a substantial decrease in drug uptake for both Xylometazoline HCl and 51Cr-EDTA. A similar result was obtained when comparing two different vehicles on the market; Nasoferm® (Nordic Drugs, Sweden) and BLOX4® (Bioglan, Sweden). Mucoadhesion based on water sorption can slow down drug uptake in the nasal cavity. However, a clinical study is required to determine whether prolonged duration of the vehicle in situ or preventing dehydration of the mucosa is the most important factor for improving bioavailability.
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Affiliation(s)
- Abdullah Ali
- a Biomedical Sciences, Faculty of Health and Society, Malmö University , Malmö , Sweden.,b Biofilms - Research Center for Biointerfaces, Malmö University , Malmö , Sweden
| | - Marie Wahlgren
- c Food Technology, Engineering and Nutrition, Lund University , Lund , Sweden
| | | | - Ameena Daftani
- a Biomedical Sciences, Faculty of Health and Society, Malmö University , Malmö , Sweden.,b Biofilms - Research Center for Biointerfaces, Malmö University , Malmö , Sweden
| | - Peter Falkman
- a Biomedical Sciences, Faculty of Health and Society, Malmö University , Malmö , Sweden.,b Biofilms - Research Center for Biointerfaces, Malmö University , Malmö , Sweden
| | - Per Wollmer
- e Department of Translational Medicine, Faculty of Medicine, Lund University , Malmö , Sweden
| | - Johan Engblom
- a Biomedical Sciences, Faculty of Health and Society, Malmö University , Malmö , Sweden.,b Biofilms - Research Center for Biointerfaces, Malmö University , Malmö , Sweden
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20
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Larsson J, Sanchez-Fernandez A, Mahmoudi N, Barnsley LC, Wahlgren M, Nylander T, Ulvenlund S. Effect of the Anomeric Configuration on the Micellization of Hexadecylmaltoside Surfactants. Langmuir 2019; 35:13904-13914. [PMID: 31566987 DOI: 10.1021/acs.langmuir.9b01960] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The self-assembly of the two anomeric forms of n-hexadecyl-d-maltopyranoside (denoted α-C16G2 and β-C16G2) has been studied in dilute aqueous solution by means of surface tension measurements, scattering methods (dynamic light scattering, static light scattering, and small-angle X-ray and neutron scattering), and cryo-transmission electron microscopy at different surfactant concentrations and temperatures. Surface tension measurements demonstrate differences in the surfactant adsorption at the air-water interface, where α-C16G2 shows a lower CMC than β-C16G2. Similarly, micelle morphology was found to profoundly depend on anomerism. β-C16G2 preferentially forms very elongated micelles with large persistence lengths, whereas α-C16G2 assembles into smaller micelles for which the structure varies with concentration and temperature. The differences between the two surfactant anomers in terms of self-assembly can be attributed to the interaction between neighboring headgroups. Specifically, β-C16G2 allows for a closer packing in the palisade layer, hence reducing the micelle curvature and promoting the formation of more elongated micelles. Strong intermolecular headgroup interactions may also account for the observed rigidity of the micelles.
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Affiliation(s)
| | | | - Najet Mahmoudi
- ISIS Neutron and Muon Source, Science & Technology Facilities Council , Rutherford Appleton Laboratory , Chilton OX11 0QX , U.K
| | - Lester C Barnsley
- Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ) , Forschungszentrum Jülich GmbH , Lichtenbergstr. 1 , 85748 Garching , Germany
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Saari H, Rayner M, Wahlgren M. Effects of starch granules differing in size and morphology from different botanical sources and their mixtures on the characteristics of Pickering emulsions. Food Hydrocoll 2019. [DOI: 10.1016/j.foodhyd.2018.11.063] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Wahlgren M, Axenstrand M, Håkansson Å, Marefati A, Lomstein Pedersen B. In Vitro Methods to Study Colon Release: State of the Art and An Outlook on New Strategies for Better In-Vitro Biorelevant Release Media. Pharmaceutics 2019; 11:E95. [PMID: 30813323 PMCID: PMC6410320 DOI: 10.3390/pharmaceutics11020095] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 02/18/2019] [Accepted: 02/21/2019] [Indexed: 12/19/2022] Open
Abstract
The primary focus of this review is a discussion regarding in vitro media for colon release, but we also give a brief overview of colon delivery and the colon microbiota as a baseline for this discussion. The large intestine is colonized by a vast number of bacteria, approximately 1012 per gram of intestinal content. The microbial community in the colon is complex and there is still much that is unknown about its composition and the activity of the microbiome. However, it is evident that this complex microbiota will affect the release from oral formulations targeting the colon. This includes the release of active drug substances, food supplements, and live microorganisms, such as probiotic bacteria and bacteria used for microbiota transplantations. Currently, there are no standardized colon release media, but researchers employ in vitro models representing the colon ranging from reasonable simple systems with adjusted pH with or without key enzymes to the use of fecal samples. In this review, we present the pros and cons for different existing in vitro models. Furthermore, we summarize the current knowledge of the colonic microbiota composition which is of importance to the fermentation capacity of carbohydrates and suggest a strategy to choose bacteria for a new more standardized in vitro dissolution medium for the colon.
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Affiliation(s)
- Marie Wahlgren
- Department of Food technology engineering and nutrition, Lund University, P.O. Box 124, 221 00 Lund, Sweden.
| | - Magdalena Axenstrand
- Department of Food technology engineering and nutrition, Lund University, P.O. Box 124, 221 00 Lund, Sweden.
| | - Åsa Håkansson
- Department of Food technology engineering and nutrition, Lund University, P.O. Box 124, 221 00 Lund, Sweden.
| | - Ali Marefati
- Department of Food technology engineering and nutrition, Lund University, P.O. Box 124, 221 00 Lund, Sweden.
| | - Betty Lomstein Pedersen
- Ferring International PharmaScience Center (IPC), Kay Fiskers Plads 11, 2300 Copenhagen, Denmark.
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Matos M, Marefati A, Gutiérrez G, Wahlgren M, Rayner M. Comparative Emulsifying Properties of Octenyl Succinic Anhydride (OSA)-Modified Starch: Granular Form vs Dissolved State. PLoS One 2016; 11:e0160140. [PMID: 27479315 PMCID: PMC4968836 DOI: 10.1371/journal.pone.0160140] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 07/14/2016] [Indexed: 11/18/2022] Open
Abstract
The emulsifying ability of OSA-modified and native starch in the granular form, in the dissolved state and a combination of both was compared. This study aims to understand mixed systems of particles and dissolved starch with respect to what species dominates at droplet interfaces and how stability is affected by addition of one of the species to already formed emulsions. It was possible to create emulsions with OSA-modified starch isolated from Quinoa as sole emulsifier. Similar droplet sizes were obtained with emulsions prepared at 7% (w/w) oil content using OSA-modified starch in the granular form or molecularly dissolved but large differences were observed regarding stability. Pickering emulsions kept their droplet size constant after one month while emulsions formulated with OSA-modified starch dissolved exhibited coalescence. All emulsions stabilized combining OSA-modified starch in granular form and in solution showed larger mean droplet sizes with no significant differences with respect to the order of addition. These emulsions were unstable due to coalescence regarding presence of free oil. Similar results were obtained when emulsions were prepared by combining OSA-modified granules with native starch in solution. The degree of surface coverage of starch granules was much lower in presence of starch in solution which indicates that OSA-starch is more surface active in the dissolved state than in granular form, although it led to unstable systems compared to starch granule stabilized Pickering emulsions, which demonstrated to be extremely stable.
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Affiliation(s)
- María Matos
- Department of Food Technology, Engineering, and Nutrition, Lund University, P.O. Box 124, SE 221 00 Lund, Sweden
- Department of Chemical and Environmental Engineering, University of Oviedo, Julián Clavería 8, 33006 Oviedo, Spain
| | - Ali Marefati
- Department of Food Technology, Engineering, and Nutrition, Lund University, P.O. Box 124, SE 221 00 Lund, Sweden
| | - Gemma Gutiérrez
- Department of Chemical and Environmental Engineering, University of Oviedo, Julián Clavería 8, 33006 Oviedo, Spain
| | - Marie Wahlgren
- Department of Food Technology, Engineering, and Nutrition, Lund University, P.O. Box 124, SE 221 00 Lund, Sweden
| | - Marilyn Rayner
- Department of Food Technology, Engineering, and Nutrition, Lund University, P.O. Box 124, SE 221 00 Lund, Sweden
- * E-mail:
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Affiliation(s)
- Hisfazilah Saari
- Department of Food Technology, Engineering and Nutrition, Lund University, Box 124, SE22100 Lund, Sweden
| | - Katayoun Heravifar
- Department of Food Technology, Engineering and Nutrition, Lund University, Box 124, SE22100 Lund, Sweden
| | - Marilyn Rayner
- Department of Food Technology, Engineering and Nutrition, Lund University, Box 124, SE22100 Lund, Sweden
| | - Marie Wahlgren
- Department of Food Technology, Engineering and Nutrition, Lund University, Box 124, SE22100 Lund, Sweden
| | - Malin Sjöö
- Department of Food Technology, Engineering and Nutrition, Lund University, Box 124, SE22100 Lund, Sweden
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26
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Egelandsdal B, Berg P, Wahlgren M, Slinde E. Glutamine and succinate stabilize shelf-life color of frozen and thawed meat by stimulation of mitochondrial respiration. Meat Sci 2016. [DOI: 10.1016/j.meatsci.2015.08.083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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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27
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Knöös P, Svensson AV, Ulvenlund S, Wahlgren M. Release of a Poorly Soluble Drug from Hydrophobically Modified Poly (Acrylic Acid) in Simulated Intestinal Fluids. PLoS One 2015; 10:e0140709. [PMID: 26473964 PMCID: PMC4608824 DOI: 10.1371/journal.pone.0140709] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 09/28/2015] [Indexed: 12/02/2022] Open
Abstract
A large part of new pharmaceutical substances are characterized by a poor solubility and high hydrophobicity, which might lead to a difference in drug adsorption between fasted and fed patients. We have previously evaluated the release of hydrophobic drugs from tablets based on Pemulen TR2 and showed that the release can be manipulated by adding surfactants. Here we further evaluate the possibility to use Pemulen TR2 in controlled release tablet formulations containing a poorly soluble substance, griseofulvin. The release is evaluated in simulated intestinal media that model the fasted state (FaSSIF medium) or fed state (FeSSIF). The rheology of polymer gels is studied in separate experiments, in order to gain more information on possible interactions. The release of griseofulvin in tablets without surfactant varied greatly and the slowest release were observed in FeSSIF. Addition of SDS to the tablets eliminated the differences and all tablets showed a slow linear release, which is of obvious relevance for robust drug delivery. Comparing the data from the release studies and the rheology experiment showed that the effects on the release from the different media could to a large extent be rationalised as a consequence of the interactions between the polymer and the surfactants in the media. The study shows that Pemulen TR2 is a candidate for controlled release formulations in which addition of surfactant provides a way to eliminate food effects on the release profile. However, the formulation used needs to be designed to give a faster release rate than the tablets currently investigated.
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Affiliation(s)
- Patrik Knöös
- Department of Chemistry, Division of Physical Chemistry, Lund University, Lund, Sweden
| | | | | | - Marie Wahlgren
- Department of food technology engineering and nutrition, Lund University, Lund, Sweden
- * E-mail:
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Sjöö M, Emek SC, Hall T, Rayner M, Wahlgren M. Barrier properties of heat treated starch Pickering emulsions. J Colloid Interface Sci 2015; 450:182-188. [DOI: 10.1016/j.jcis.2015.03.004] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 03/03/2015] [Accepted: 03/04/2015] [Indexed: 11/28/2022]
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Söderberg L, Engblom J, Lanbeck P, Wahlgren M. Do surface active parenteral formulations cause inflammation? Int J Pharm 2015; 484:246-51. [PMID: 25708007 DOI: 10.1016/j.ijpharm.2015.02.045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [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: 11/08/2014] [Accepted: 02/17/2015] [Indexed: 11/30/2022]
Abstract
Local irritation and inflammation at the site of administration are a common side effect following administration of parenteral formulations. Biological effects of surface (interfacial) activity in solutions are less well investigated than effects caused by other physico-chemical parameters such as pH and osmolality. The interfacial activity in different systems, including human plasma, typical amphiphilic substances with fundamental biological relevance such as free fatty acids, anesthetic depot formulations and six different antibiotics was measured. The relative interfacial pressure, and/or concentration of active substance, required to obtain 50% of the maximal attainable effect in terms of interfacial pressure were calculated. The aim was to test the hypothesis that these parameters would allow comparison to biological effects reported in in vivo studies on the investigated substances. The highest interfacial activity was found in a triglyceride/plasma system. Among the antibiotic tested, the highest interfacial activities were found in erythromycin and dicloxacillin, which is in accordance with previous clinical findings of a high tendency of infusion phlebitis and cell toxicity. Independently of investigated system, biological effects were minimal below a 15% relative increase of interfacial activity. Above 35-45% the effects were severe. Interfacial activity in parenteral formulations may well cause damages to tissues followed by inflammation.
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Affiliation(s)
- Lars Söderberg
- Department of Biomedical Science, Malmö University, SE-205 06 Malmö, Sweden; Biofilms - Research Center for Biointerfaces, Malmö University, Malmö, Sweden; Clinical Physiology and Nuclear Medicine Unit, Department of Clinical Sciences, Lund University, Malmö, Sweden.
| | - Johan Engblom
- Department of Biomedical Science, Malmö University, SE-205 06 Malmö, Sweden; Biofilms - Research Center for Biointerfaces, Malmö University, Malmö, Sweden.
| | - Peter Lanbeck
- Infectious Diseases Research Unit, Department of Clinical Sciences, Lund University, Malmö, Sweden.
| | - Marie Wahlgren
- Department of Food Technology, Lund University, SE-221 00 Lund, Sweden.
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Gari H, Rembiesa J, Masilionis I, Vreva N, Svensson B, Sund T, Hansson H, Morén AK, Sjöö M, Wahlgren M, Engblom J, Ruzgas T. Amperometric In Vitro Monitoring of Penetration through Skin Membrane. ELECTROANAL 2014. [DOI: 10.1002/elan.201400426] [Citation(s) in RCA: 5] [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] [Indexed: 02/02/2023]
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Rayner M, Marku D, Eriksson M, Sjöö M, Dejmek P, Wahlgren M. Biomass-based particles for the formulation of Pickering type emulsions in food and topical applications. Colloids Surf A Physicochem Eng Asp 2014. [DOI: 10.1016/j.colsurfa.2014.03.053] [Citation(s) in RCA: 208] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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32
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Knöös P, Wahlgren M, Topgaard D, Ulvenlund S, Piculell L. Effects of Added Surfactant on Swelling and Molecular Transport in Drug-Loaded Tablets Based on Hydrophobically Modified Poly(acrylic acid). J Phys Chem B 2014; 118:9757-67. [DOI: 10.1021/jp501288u] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [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)
| | | | | | - Stefan Ulvenlund
- CR Competence AB, c/o Chemical Centre,
Box 124, SE-221 00, Lund, Sweden
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Knöös P, Schulz C, Piculell L, Ludwig R, Gorton L, Wahlgren M. Quantifying the release of lactose from polymer matrix tablets with an amperometric biosensor utilizing cellobiose dehydrogenase. Int J Pharm 2014; 468:121-32. [PMID: 24726632 DOI: 10.1016/j.ijpharm.2014.03.060] [Citation(s) in RCA: 10] [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: 01/31/2014] [Revised: 03/28/2014] [Accepted: 03/30/2014] [Indexed: 10/25/2022]
Abstract
The release of lactose (hydrophilic) from polymer tablets made with hydrophobically modified poly(acrylic acid) (HMPAA) have been studied and compared to the release of ibuprofen, a hydrophobic active substance. Lactose is one of the most used excipients for tablets, but lactose release has not been widely studied. One reason could be a lack of good analytical tools. A novel biosensor with cellobiose dehydrogenase (CDH) was used to detect the lactose release, which has a polydiallyldimethylammonium chloride (PDADMAC) layer that increases the response. A sample treatment using polyethylenimine (PEI) was developed to eliminate possible denaturants. The developed methodology provided a good approach to detect and quantify the released lactose. The release was studied with or without the presence of a model amphiphilic substance, sodium dodecyl sulphate (SDS), in the release medium. Ibuprofen showed very different release rates in the different media, which was attributed to hydrophobic interactions between the drug, the HMPAA and the SDS in the release medium. The release of hydrophilic lactose, which did not associate to any of the other components, was rapid and showed only minor differences. The new methodology provides a useful tool to further evaluate tablet formulations by a relatively simple set of experiments.
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Affiliation(s)
- Patrik Knöös
- Division of Physical Chemistry, Lund University, Box 124, Lund SE-22100, Sweden.
| | - Christopher Schulz
- Department of Biochemistry and Structural Biology, Lund University, Box 124, Lund SE-22100, Sweden.
| | - Lennart Piculell
- Division of Physical Chemistry, Lund University, Box 124, Lund SE-22100, Sweden
| | - Roland Ludwig
- Food Biotechnology Laboratory, Department of Food Sciences and Technology, BOKU University of Natural Resources and Life Sciences, Vienna, Austria
| | - Lo Gorton
- Department of Biochemistry and Structural Biology, Lund University, Box 124, Lund SE-22100, Sweden
| | - Marie Wahlgren
- Division of Food Technology, Lund University, Box 124, Lund SE-22100, Sweden.
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Wahlgren M, Engblom J, Sjoo M, Rayner M. The Use of Micro- and Nanoparticles in the Stabilisation of Pickering-Type Emulsions for Topical Delivery. Curr Pharm Biotechnol 2014; 14:1222-34. [DOI: 10.2174/1389201015666140317122135] [Citation(s) in RCA: 22] [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: 09/24/2013] [Revised: 02/03/2014] [Accepted: 03/11/2014] [Indexed: 11/22/2022]
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Knöös P, Topgaard D, Wahlgren M, Ulvenlund S, Piculell L. Using NMR chemical shift imaging to monitor swelling and molecular transport in drug-loaded tablets of hydrophobically modified poly(acrylic acid): methodology and effects of polymer (in)solubility. Langmuir 2013; 29:13898-13908. [PMID: 24106807 DOI: 10.1021/la4024458] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A new technique has been developed using NMR chemical shift imaging (CSI) to monitor water penetration and molecular transport in initially dry polymer tablets that also contain small low-molecular weight compounds to be released from the tablets. Concentration profiles of components contained in the swelling tablets could be extracted via the intensities and chemical shift changes of peaks corresponding to protons of the components. The studied tablets contained hydrophobically modified poly(acrylic acid) (HMPAA) as the polymer component and griseofulvin and ethanol as hydrophobic and hydrophilic, respectively, low-molecular weight model compounds. The water solubility of HMPAA could be altered by titration with NaOH. In the pure acid form, HMPAA tablets only underwent a finite swelling until the maximum water content of the polymer-rich phase, as confirmed by independent phase studies, had been reached. By contrast, after partial neutralization with NaOH, the polyacid became fully miscible with water. The solubility of the polymer affected the water penetration, the polymer release, and the releases of both ethanol and griseofulvin. The detailed NMR CSI concentration profiles obtained highlighted the clear differences in the disintegration/dissolution/release behavior for the two types of tablet and provided insights into their molecular origin. The study illustrates the potential of the NMR CSI technique to give information of importance for the development of pharmaceutical tablets and, more broadly, for the general understanding of any operation that involves the immersion and ultimate disintegration of a dry polymer matrix in a solvent.
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Affiliation(s)
- Patrik Knöös
- Division of Physical Chemistry, Lund University , Box 124, SE-221 00 Lund, Sweden
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Ivarsson D, Wahlgren M. Comparison of in vitro methods of measuring mucoadhesion: ellipsometry, tensile strength and rheological measurements. Colloids Surf B Biointerfaces 2011; 92:353-9. [PMID: 22209653 DOI: 10.1016/j.colsurfb.2011.12.020] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Revised: 11/10/2011] [Accepted: 12/14/2011] [Indexed: 11/25/2022]
Abstract
In this work three in vitro methods for the measurement of mucoadhesion have been compared: ellipsometry, tensile strength and rheology. The conditions used for the three methods have been as similar as possible. Six different polymers were investigated: sodium carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC), chitosan, polyvinyl pyrrolidone (PVP) and two cross-linked polyacrylic acids, Noveon (hydrophobically modified) and Carbopol. The results showed that PVP did not exhibit mucoadhesion according to any of the methods used. Chitosan, Noveon, Carbopol, CMC and HEC showed good mucoadhesion in the tensile strength and the rheological measurements, but not in the ellipsometry investigation. Chitosan was the only polymer showing good mucoadhesion with the ellipsometry method. No two methods gave the same ranking of mucoadhesive strength of the polymers. The conflicting results obtained with the different methods underline the need for further improvements in existing experimental techniques and theoretical concepts for the correct assessment of mucoadhesive properties.
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Affiliation(s)
- David Ivarsson
- Department of Food Technology, Lund University, Lund, Sweden
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Fredenberg S, Jönsson M, Laakso T, Wahlgren M, Reslow M, Axelsson A. Development of mass transport resistance in poly(lactide-co-glycolide) films and particles – A mechanistic study. Int J Pharm 2011; 409:194-202. [DOI: 10.1016/j.ijpharm.2011.02.066] [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: 01/13/2011] [Revised: 02/26/2011] [Accepted: 02/28/2011] [Indexed: 11/15/2022]
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Fredenberg S, Wahlgren M, Reslow M, Axelsson A. Pore formation and pore closure in poly(D,L-lactide-co-glycolide) films. J Control Release 2011; 150:142-9. [DOI: 10.1016/j.jconrel.2010.11.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2010] [Revised: 11/05/2010] [Accepted: 11/15/2010] [Indexed: 10/18/2022]
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Ivanov AE, Solodukhina N, Wahlgren M, Nilsson L, Vikhrov AA, Nikitin MP, Orlov AV, Nikitin PI, Kuzimenkova MV, Zubov VP. Reversible conformational transitions of a polymer brush containing boronic acid and its interaction with mucin glycoprotein. Macromol Biosci 2010; 11:275-84. [PMID: 21136536 DOI: 10.1002/mabi.201000295] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Revised: 09/09/2010] [Indexed: 11/06/2022]
Abstract
Reversible changes of the height of a polymer brush containing phenylboronic acid were studied. The polymer brush thickness underwent reversible changes of 0.5-1 nm, in response to the changes in composition of the contacting aqueous phase from deionized water to bicarbonate buffer and vice versa, apparently due to the conformational transition of the weak polyelectrolyte to the more extended electrically charged state. Adsorption of mucin glycoprotein to the polymer brush took place due to boronate/sugar interactions between the glycoprotein and the graft copolymer and resulted in further increase of the brush height by ca. 1.5 nm, as observed by means of spectral correlation spectroscopy and ellipsometry.
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Balogun H, Vasconcelos NM, Lindberg R, Haeggström M, Moll K, Chen Q, Wahlgren M, Berzins K. Immunogenicity and antigenic properties of Pf332-C231, a fragment of a non-repeat region of the Plasmodium falciparum antigen Pf332. Vaccine 2009; 28:90-7. [DOI: 10.1016/j.vaccine.2009.09.110] [Citation(s) in RCA: 8] [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: 06/29/2009] [Revised: 09/18/2009] [Accepted: 09/25/2009] [Indexed: 10/20/2022]
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Elfstrand L, Eliasson AC, Wahlgren M. The Effect of Starch Material, Encapsulated Protein and Production Conditions on the Protein Release from Starch Microspheres. J Pharm Sci 2009; 98:3802-15. [DOI: 10.1002/jps.21693] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Wahlgren M, Christensen KL, Jørgensen EV, Svensson A, Ulvenlund S. Oral-based controlled release formulations using poly(acrylic acid) microgels. Drug Dev Ind Pharm 2009; 35:922-9. [DOI: 10.1080/03639040802698810] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Söderberg L, Haag L, Höglund P, Roth B, Stenberg P, Wahlgren M. The effects of lipophilic substances on the shape of erythrocytes demonstrated by a new in vitro-method. Eur J Pharm Sci 2009; 36:458-64. [DOI: 10.1016/j.ejps.2008.11.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2008] [Revised: 11/13/2008] [Accepted: 11/26/2008] [Indexed: 11/27/2022]
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Elfstrand L, Eliasson AC, Jönsson M, Reslow M, Thelin B, Wahlgren M. Recrystallization of waxy maize starch during manufacturing of starch microspheres for drug delivery: Optimization by experimental design. Carbohydr Polym 2007. [DOI: 10.1016/j.carbpol.2006.10.017] [Citation(s) in RCA: 14] [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: 11/25/2022]
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Elfstrand L, Eliasson AC, Jönsson M, Reslow M, Wahlgren M. From Starch to Starch Microspheres: Factors Controlling the Microspheres Quality. STARCH-STARKE 2006. [DOI: 10.1002/star.200600489] [Citation(s) in RCA: 22] [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: 11/08/2022]
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Rasti N, Falk KI, Donati D, Gyan BA, Goka BQ, Troye-Blomberg M, Akanmori BD, Kurtzhals JAL, Dodoo D, Consolini R, Linde A, Wahlgren M, Bejarano MT. Circulating epstein-barr virus in children living in malaria-endemic areas. Scand J Immunol 2005; 61:461-5. [PMID: 15882438 DOI: 10.1111/j.1365-3083.2005.01589.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [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: 01/29/2023]
Abstract
Children living in malaria-endemic regions have high incidence of Burkitt's lymphoma (BL), the aetiology of which involves Plasmodium falciparum malaria and Epstein-Barr virus (EBV) infections. Acute malarial infection impairs the EBV-specific immune responses with the consequent increase in the number of EBV-carrying B cells in the circulation. To further understand the potential influence of malarial infection on the EBV persistence in children living in malaria-endemic areas, we studied the occurrence and quantified cell-free EBV-DNA in plasma from 73 Ghanaian children with and without acute malarial infection. Viral DNA was detected in 40% of the samples (47% in the malaria-infected and 34% in the nonmalaria group) but was absent in plasma from Ghanaian adults and healthy Italian children. These findings provide evidence that viral reactivation is common among children living in malaria-endemic areas, and may contribute to the increased risk for endemic BL. The data also suggest that the epidemiology of EBV infection and persistence varies in different areas of the world.
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Affiliation(s)
- N Rasti
- Microbiology and Tumor Biology Center, Karolinska Institute, Stockholm, Sweden
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Wahlgren M, Carlson J, Udomsangpetch R, Perlmann P. Why do Plasmodium falciparumm-infected erythrocytes form spontaneous erythrocyte rosettes? ACTA ACUST UNITED AC 2005; 5:183-5. [PMID: 15463207 DOI: 10.1016/0169-4758(89)90141-5] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Plasmodium falciparum malaria is one o f the most widespread o f human parasitic diseases and is responsible for the deaths of several million people in subtropical and tropical regions o f the world. The interaction o f malarial merozoites with erythrocytes and the adherence o f infected erythrocytes to the endothelium are among the cellular interactions extensively studied to define candidate antigens for a blood stage vaccine. However, the exact mechanisms underlying the invasion o f erythrocytes by P. falciparum merozoites and their subsequent binding to endothelium are not yet understood. Here Mats Wahlgren, Johan Carlson, Rachonee Udomsangpetch and Peter Perlmonn discuss a novel cytoodherence phenomenon which may be o f great importance in this context, that is, the spontaneous binding o f uninfected erythrocytes to those infected with late-stage parasites (trophozoites/schizonts).
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Affiliation(s)
- M Wahlgren
- Department of Immunology, University of Stockholm, S-106 91 Stockholm, Sweden
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Elfstrand L, Frigård T, Andersson R, Eliasson AC, Jönsson M, Reslow M, Wahlgren M. Recrystallisation behaviour of native and processed waxy maize starch in relation to the molecular characteristics. Carbohydr Polym 2004. [DOI: 10.1016/j.carbpol.2004.05.018] [Citation(s) in RCA: 19] [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] [Indexed: 10/26/2022]
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Tufvesson F, Wahlgren M, Eliasson AC. Formation of Amylose-Lipid Complexes and Effects of Temperature Treatment. Part 2. Fatty Acids. STARCH-STARKE 2003. [DOI: 10.1002/star.200390028] [Citation(s) in RCA: 166] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Tufvesson F, Wahlgren M, Eliasson AC. Formation of Amylose-Lipid Complexes and Effects of Temperature Treatment. Part 1. Monoglycerides. STARCH-STARKE 2003. [DOI: 10.1002/star.200390018] [Citation(s) in RCA: 129] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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