Abstract
The structural characteristics of liposomes have been widely investigated and there is certainly a strong understanding of their morphological characteristics. Imaging of these systems, using techniques such as freeze-fracturing methods, transmission electron microscopy, and cryo-electron imaging, has allowed us to appreciate their bilayer structures and factors which can influence this. However, there are few methods which all us to study these systems in their natural hydrated state; commonly the liposomes are visualized after drying, staining, and/or fixation of the vesicles. Environmental Scanning Electron Microscopy (ESEM) offers the ability to image a liposome in its hydrated state without the need for prior sample preparation. Within our studies we were the first to use ESEM to study liposomes and niosomes and we have been able to dynamically follow the hydration of lipid films and changes in liposome suspensions as water condenses on to, or evaporates from, the sample in real time. This provides insight into the resistance of liposomes to coalescence during dehydration, thereby providing an alternative assay of liposome formulation and stability.
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Acknowledgements
The authors gratefully acknowledge the financial support for the following researchers: during the time of this work Afzal Mohammed’s was supported by Pfizer Global Research and The School of Life and Health Sciences, Aston University; Anil Vangala was awarded an Aston Scholarship; Daniel Kirby was funded by the European Commission (contract no. LSHP-CT-2003-503367), Habib Ali and Sarah McNeil were both funded through EPSRC Case awards, with additional support from Lipoxen Technologies Ltd for Sarah McNeil.
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Perrie, Y., Ali, H., Kirby, D.J., Mohammed, A.U.R., McNeil, S.E., Vangala, A. (2017). Environmental Scanning Electron Microscope Imaging of Vesicle Systems. In: D'Souza, G. (eds) Liposomes. Methods in Molecular Biology, vol 1522. Humana Press, New York, NY. https://doi.org/10.1007/978-1-4939-6591-5_11
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DOI: https://doi.org/10.1007/978-1-4939-6591-5_11
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