Page 54 - ILL Annual Report 2019

SOFT CONDENSED MATTER
Tommy Nylander. Swedish
Department of Chemistry, Lund University, Sweden
‘I work with various types of biomolecules, such as lipids, proteins and carbohydrates. I use neutron scattering and reflectometry because I want to know the relation between their function and structure at bulk and interfaces.’
Interfacial properties of lipid, sponge-like nanoparticles and the role of a stabiliser on particle structure and surface interactions
Reflectometer for the analysis of materials SuperADAM
The formulation of drugs, e.g. for cancer treatment, genetherapy, metabolic disorders, opioid dependence, is a question not only of solubilising the therapeutic compound but also of making sure that it stays dispersed for a long time. Non-lamellar lipid liquid crystalline nanoparticles (LCNPs) are now widely considered in many applications as they have good solubilising capability and tuneable properties and can be prepared from natural lipids. Our study is directed at understanding their structure and properties so that in the future we can produce long- lasting, stable formulations. We use neutron surface and bulk scattering as well as reflectometry techniques for this purpose, as we want the formulation to be deposited at a targeted interface and not get to stuck at the walls of a container or delivery system.
AUTHORS
M. Valldeperas and T. Nylander (NanoLund and Lund University, Sweden) G.K. Pálsson and A. Vorfobiev (ILL and Uppsala University, Sweden)
A. Dabkowska (IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden) and J. Barauskas (Camurus AB, Lund, Sweden)
ARTICLE FROM
Soft Matter (2019)—doi: 10.1039/c8sm02634c
REFERENCES
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[2] K. Larsson, Curr. Opin. Colloid Interface Sci. 5 (2000) 64
[3] L. Sagalowicz and M.E. Leser, Curr. Opin. Colloid Interface Sci.
15 (2010) 61
[4] J. Barauskas and T. Nylander, in Delivery and Controlled Release
of Bioactives in Foods and Nutraceuticals, Woodhead Publishing
Limited, Abington, England (2008) 107
[5] C.E. Conn and C.J. Drummond, Soft Matter 9 (2013) 3449 [6] V. Razumas, J. Kanapieniené, T. Nylander, S. Engström and
K. Larsson, Anal. Chim. Acta 289 (1994) 155
[7] J. Gilbert, M. Valldeperas, S.K. Dhayal, J. Barauskas, C. Dicko
and T. Nylander, Nanoscale 11 (2019) 21291
[8] B. Angelov, A. Angelova, R. Mutafchieva, S. Lesieur, U. Vainio,
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[9] D.P. Chang, J. Barauskas, A.P. Dabkowska, M. Wadsäter, F. Tiberg
and T. Nylander, Adv. Colloid Interface Sci. 222 (2015) 135 [10] P. Vandoolaeghe, R.A. Campbell, A.R. Rennie and T. Nylander,
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[11] A. Vorobiev, A. Devishvilli, G. Palsson, H. Rundlöf, N. Johansson,
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It is by now well-established that lipid-forming liquid crystalline phases can be dispersed into nanoparticles, where the lipid composition can be used to tune the internal structure to an inverse cubic, sponge-phase or hexagonal structure (cubosomes, spongosomes and hexosomes, respectively) [1–3]. They have a larger surface area per volume ratio and a larger capability to solubilise both hydrophilic and hydrophobic molecules compared with their lamellar analogues (vesicles) [2–3]. Due to their well-defined internal structure, colloidal stability and tuneable internal structure, they have found applications in drug delivery and in protein encapsulation or crystallisation [2–6].
This study focuses on the lipid sponge phase (L3), which is more flexible, has a greater capacity to form larger aqueous pores compared with the structurally similar bicontinuous cubic phase and is therefore capable of encapsulating larger bioactive molecules such as enzymes [7–8]. We have previously examined the interfacial properties of cubosomes and hexosomes in order to understand the nature of the interactions between these LCNPs and various interfaces that mimic storage or administration vessels, such as glass vials, catheters and syringes [9–10].
The current study also provided the means to determine the colloidal stability of these particles and give insight into their surface properties. Colloidally stable LCNPs
with a narrow size distribution are ensured by using a stabiliser that reduces the LCNP aqueous phase interfacial tension. Common stabilisers are Pluronic F127 and Polysorbate 80; they are not only stabilisers but have also been found to affect the internal particle structure [10].
ANNUAL REPORT 2019