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Novel Method for Visualizing Water Transport Through Phase-Separated Polymer Films

Published online by Cambridge University Press:  25 February 2014

Anna Jansson*
Affiliation:
Department of Applied Physics, Chalmers University of Technology, SE-41296 Gothenburg, Sweden
Catherine Boissier
Affiliation:
AstraZeneca R&D Mölndal, SE-43183 Mölndal, Sweden
Mariagrazia Marucci
Affiliation:
AstraZeneca R&D Mölndal, SE-43183 Mölndal, Sweden
Mark Nicholas
Affiliation:
AstraZeneca R&D Mölndal, SE-43183 Mölndal, Sweden
Stefan Gustafsson
Affiliation:
Department of Applied Physics, Chalmers University of Technology, SE-41296 Gothenburg, Sweden
Anne-Marie Hermansson
Affiliation:
Department of Chemical and Biological Engineering, Chalmers University of Technology, SE-41296 Gothenburg, Sweden
Eva Olsson
Affiliation:
Department of Applied Physics, Chalmers University of Technology, SE-41296 Gothenburg, Sweden
*
*Corresponding author. [email protected]
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Abstract

Drug release from oral pharmaceutical formulations can be modified by applying a polymeric coating film with controlled mass transport properties. Interaction of the coating film with water may crucially influence its composition and permeability to both water and drug. Understanding this interaction between film microstructure, wetting, and mass transport is important for the development of new coatings. We present a novel method for controlled wetting of polymer coating films in an environmental scanning electron microscope, providing direct visual information about the processes occurring as the film goes from dry to wet. Free films made of phase-separated blends of water-insoluble ethyl cellulose (EC) and water-soluble hydroxypropyl cellulose (HPC) were used as a model system, and the blend ratio was varied to study the effect on the water transport properties. Local variations in water transport through the EC/HPC films were directly observed, enabling the immediate analysis of the structure–mass transport relationships. The leaching of HPC could be studied by evaporating water from the films in situ. Significant differences were observed between films of varying composition. The method provides a valuable complement to the current approach of making distinct diffusion and microscopy experiments for studying the dynamic interaction of polymer films with water.

Type
In Situ Special Section
Copyright
© Microscopy Society of America 2014 

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References

Alink, R., Gerteisen, D. & Mérida, W. (2011). Investigating the water transport in porous media for PEMFCs by liquid water visualization in ESEM. Fuel Cells 11(4), 481488.Google Scholar
Andersson, H., Hjärtstam, J., Stading, M., von Corswant, C. & Larsson, A. (2013). Effects of molecular weight on permeability and microstructure of mixed ethyl-hydroxypropyl-cellulose films. Eur J Pharm Sci 48, 240248.Google Scholar
Boissier, C., Feidt, F. & Nordstierna, L. (2012). Study of pharmaceutical coatings by means of NMR cryoporometry and SEM image analysis. J Pharm Sci 101(7), 25122522.Google Scholar
Brown, G. & Chakrabarti, A. (1993). Phase separation dynamics in off-critical polymer blends. J Chem Phys 98, 24512458.CrossRefGoogle Scholar
Chinnan, M.S. & Park, H.J. (1995). Effect of plasticizer level and temperature on water vapor transmission of cellulose-based edible films. J Food Process Eng 18(4), 417429.Google Scholar
Donbrow, M. & Samuelov, Y. (1980). Zero order drug delivery from double-layered porous film: Release rate profiles from ethyl cellulose, hydroxypropyl cellulose and polyethylene glycol. J Pharm Pharmacol 32, 463470.Google Scholar
Egerton, R.F., Li, P. & Malac, M. (2004). Radiation damage in the TEM and SEM. Micron 35, 399409.Google Scholar
Frohoff-Hülsmann, M.A., Lippold, B.C. & McGinity, J.W. (1999). Aqueous ethyl cellulose dispersion containing plasticizers of different water solubility and hydroxypropyl methyl-cellulose as coating material for diffusion pellets II: Properties of sprayed films. Eur J Pharm Biopharm 48(1), 6775.Google Scholar
Gunder, W., Lippold, B.H. & Lippold, B.C. (1995). Release of drugs from ethyl cellulose microcapsules (diffusion pellets) with pore formers and pore fusion. Eur J Pharm Sci 3(4), 203214.Google Scholar
Hjärtstam, J. & Hjertberg, T. (1999). Studies of the water permeability and mechanical properties of a film made of an ethyl cellulose–ethanol–water ternary mixture. J Appl Polym Sci 74(8), 20562062.Google Scholar
Jansson, A., Nafari, A., Sanz-Velasco, A., Svensson, K., Gustafsson, S., Hermansson, A.-M. & Olsson, E. (2013). Novel method for controlled wetting of materials in the environmental scanning electron microscope. Microsc Microanal 19(1), 3037.Google Scholar
Kaul, A. (2000). The phase diagram. In Aqueous Two-Phase Systems: Methods and Protocols, Hatti-Kaul, R. (Ed.), pp. 1121. Totowa, NJ: Humana Press.Google Scholar
Larez-V, C., Crescenzi, V. & Ciferri, A. (1995). Phase separation of rigid polymers in poor solvents. 1. (Hydroxypropyl)cellulose in water. Macromolecules 28(15), 52805284.Google Scholar
Lesne, A. & Laguës, M. (2012). Scale Invariance: From Phase Transitions to Turbulence. Berlin and Heidelberg: Springer-Verlag.Google Scholar
Levine, H. & Slade, L. (1988). Water as a plasticizer: Physico-chemical aspects of low-moisture polymeric systems. In Water Science Reviews 3: Water Dynamics, Franks, F. (Ed.), pp. 79185. Cambridge, UK: Cambridge University Press.Google Scholar
Lindstedt, B., Ragnarsson, G. & Hjärtstam, J. (1989). Osmotic pumping as a release mechanism for membrane-coated drug formulations. Int J Pharm 56, 261268.Google Scholar
Liukkonen, A. (1997). Contact angle of water on paper components: Sessile drops versus environmental scanning electron microscope measurements. Scanning 19(6), 411415.Google Scholar
Lua, Y., Cao, X., Rohrs, B.R. & Aldrich, D.S. (2007). Surface characterizations of spin-coated films of ethylcellulose and hydroxypropyl methylcellulose blends. Langmuir 23, 42864292.Google Scholar
Marucci, M., Arnehed, J., Jarke, A., Matic, H., Nicholas, M., Boissier, C. & von Corswant, C. (2013). Effect of the manufacturing conditions on the structure and permeability of polymer films intended for coating undergoing phase separation. Eur J Pharm Biopharm 83, 301306.Google Scholar
Marucci, M., Hjärtstam, J., Ragnarsson, G., Iselau, F. & Axelsson, A. (2009). Coated formulations: New insights into the release mechanism and changes in the film properties with a novel release cell. J Control Release 136, 206212.Google Scholar
Mills, R. (1973). Self-diffusion in normal and heavy water in the range 1-45.deg. J Phys Chem 77(5), 685688.Google Scholar
Montes-H, G., Geraud, Y., Duplay, J. & Reuschle, T. (2005). ESEM observations of compacted bentonite submitted to hydration/dehydration conditions. Colloids Surf A 262, 1422.Google Scholar
Monteux, C., Elmaallem, Y., Narita, T. & Lequeux, F. (2008). Advancing-drying droplets of polymer solutions: Local increase of the viscosity at the contact line. Euro Phys Lett 83(3), 34005.Google Scholar
Nobel, P.S. (2005). Physicochemical and Environmental Plant Physiology. Burlington, USA: Academic Press.Google Scholar
Perfetti, G., Alphazan, T., van Hee, P., Wildeboer, W.J. & Meesters, G.M.H. (2011). Relation between surface roughness of free films and process parameters in spray coating. Eur J Pharm Sci 42, 262272.Google Scholar
Reich, S. (1986). Percolation characteristics of spinodal phase separation in polymer blends. Phys Lett A 114(2), 9094.Google Scholar
Reingruber, H., Zankel, A., Mayrhofer, C. & Poelt, P. (2012). A new in situ method for the characterization of membranes in a wet state in the environmental scanning electron microscope. J Membr Sci 399–400, 8694.Google Scholar
Sakellariou, P. & Rowe, R.C. (1995). Interactions in cellulose derivative films for oral drug delivery. Prog Polym Sci 20(5), 889942.Google Scholar
Sakellariou, P., Rowe, R.C. & White, E.F.T. (1986). Polymer/polymer interaction in blends of ethyl cellulose with both cellulose derivatives and polyethylene glycol6000. Int J Pharm 34, 93103.Google Scholar
Siepmann, F., Siepmann, J., Walther, M., MacRae, R.J. & Bodmeier, R. (2008). Polymer blends for controlled release coatings. J Control Release 125(1), 115.Google Scholar
Siggia, E.D. (1979). Late stages of spinodal decomposition in binary mixtures. Phys Rev A 20(2), 595605.Google Scholar
Stokes, D.J. (2008). Principles and Practice of Variable Pressure/Environmental Scanning Electron Microscopy (VP-ESEM). West Sussex, UK: John Wiley & Sons Ltd.Google Scholar
Svensson, K., Jompol, Y., Olin, H. & Olsson, E. (2003). Compact design of a transmission electron microscope-scanning tunneling microscope holder with three-dimensional coarse motion. Rev Sci Instrum 74(11), 49454947.Google Scholar
Sudo, S. (2011). Dielectric properties of the free water in hydroxypropyl cellulose. J Phys Chem B 115, 26.Google Scholar
Umprayn, K., Chitropas, P. & Amarekajorn, S. (1999). Development of terbutaline sulfate sustained-release coated pellets. Drug Dev Ind Pharm 25, 477491.Google Scholar