Lipid bilayers cushioned with polyelectrolyte-based films on doped silicon surfaces

Lipid bilayers cushioned with polyelectrolyte-based films on doped silicon surfaces

Poltorak, L. (TU Delft OLD ChemE/Organic Materials and Interfaces)
Verheijden, Mark L. (University of Twente)
Bosma, D. (TU Delft ChemE/O&O groep)
Jonkheijm, Pascal (University of Twente)
de Smet, L.C.P.M. (TU Delft OLD ChemE/Organic Materials and Interfaces; Wageningen University & Research)
Sudhölter, Ernst J. R. (TU Delft OLD ChemE/Organic Materials and Interfaces)

2018

Silicon semiconductors with a thin surface layer of silica were first modified with polyelectrolytes (polyethyleneimine, polystyrene sulfonate and poly(allylamine)) via a facile layer-by-layer deposition approach. Subsequently, lipid vesicles were added to the preformed polymeric cushion, resulting in the adsorption of intact vesicles or fusion and lipid bilayer formation. To study involved interactions we employed optical reflectometry, electrochemical impedance spectroscopy and fluorescent recovery after photobleaching. Three phospholipids with different charge of polar head groups, i.e. 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), 1,2-dioleoyl-sn-glycero-3-phospho-L-serine (DOPS) and 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) were used to prepare vesicles with varying surface charge. We observed that only lipid vesicles composed from 1:1 (mole:mole) mixture of DOPC/DOPS have the ability to fuse onto an oppositely charged terminal layer of polyelectrolyte giving a lipid bilayer with a resistance of >100 kΩ. With optical reflectometry we found that the vesicle surface charge is directly related to the amount of mass adsorbed onto the surface. An interesting observation was that zwitterionic polar head groups of DOPC allow the adsorption on both positively and negatively charged surfaces. As found with fluorescent recovery after photobleaching, positively charged surface governed by the presence of poly(allylamine) as the terminal layer resulted in intact DOPC lipid vesicles adsorption whereas in the case of a negatively charged silica surface formation of lipid bilayers was observed, as expected from literature.

Electrochemical impedance spectroscopy
Layer-by-layer deposition
Silicon semiconductor
Supported lipid bilayer
Thin polymeric cushion

http://resolver.tudelft.nl/uuid:63db2409-99d0-4471-b968-2305485dadb5

https://doi.org/10.1016/j.bbamem.2018.09.018

2019-10-16

0005-2736

Biochimica et Biophysica Acta - Biomembranes, 1860 (12), 2669-2680

Accepted Author Manuscript

Institutional Repository

journal article

© 2018 L. Poltorak, Mark L. Verheijden, D. Bosma, Pascal Jonkheijm, L.C.P.M. de Smet, Ernst J. R. Sudhölter