1
|
Cisternas MA, Palacios-Coddou F, Molina S, Retamal MJ, Gomez-Vierling N, Moraga N, Zelada H, Soto-Arriaza MA, Corrales TP, Volkmann UG. Dry Two-Step Self-Assembly of Stable Supported Lipid Bilayers on Silicon Substrates. Int J Mol Sci 2020; 21:E6819. [PMID: 32957654 PMCID: PMC7555443 DOI: 10.3390/ijms21186819] [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: 08/31/2020] [Revised: 09/13/2020] [Accepted: 09/16/2020] [Indexed: 11/17/2022] Open
Abstract
Artificial membranes are models for biological systems and are important for applications. We introduce a dry two-step self-assembly method consisting of the high-vacuum evaporation of phospholipid molecules over silicon, followed by a subsequent annealing step in air. We evaporate dipalmitoylphosphatidylcholine (DPPC) molecules over bare silicon without the use of polymer cushions or solvents. High-resolution ellipsometry and AFM temperature-dependent measurements are performed in air to detect the characteristic phase transitions of DPPC bilayers. Complementary AFM force-spectroscopy breakthrough events are induced to detect single- and multi-bilayer formation. These combined experimental methods confirm the formation of stable non-hydrated supported lipid bilayers with phase transitions gel to ripple at 311.5 ± 0.9 K, ripple to liquid crystalline at 323.8 ± 2.5 K and liquid crystalline to fluid disordered at 330.4 ± 0.9 K, consistent with such structures reported in wet environments. We find that the AFM tip induces a restructuring or intercalation of the bilayer that is strongly related to the applied tip-force. These dry supported lipid bilayers show long-term stability. These findings are relevant for the development of functional biointerfaces, specifically for fabrication of biosensors and membrane protein platforms. The observed stability is relevant in the context of lifetimes of systems protected by bilayers in dry environments.
Collapse
Affiliation(s)
- Marcelo A. Cisternas
- Instituto de Fisica, Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.A.C.); (F.P.-C.); (S.M.); (N.G.-V.); (N.M.); (H.Z.)
- Centro de Investigacion en Nanotecnologia y Materiales Avanzados (CIEN-UC), Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.J.R.); (M.A.S.-A.)
| | - Francisca Palacios-Coddou
- Instituto de Fisica, Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.A.C.); (F.P.-C.); (S.M.); (N.G.-V.); (N.M.); (H.Z.)
- Centro de Investigacion en Nanotecnologia y Materiales Avanzados (CIEN-UC), Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.J.R.); (M.A.S.-A.)
| | - Sebastian Molina
- Instituto de Fisica, Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.A.C.); (F.P.-C.); (S.M.); (N.G.-V.); (N.M.); (H.Z.)
- Centro de Investigacion en Nanotecnologia y Materiales Avanzados (CIEN-UC), Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.J.R.); (M.A.S.-A.)
| | - Maria Jose Retamal
- Centro de Investigacion en Nanotecnologia y Materiales Avanzados (CIEN-UC), Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.J.R.); (M.A.S.-A.)
- Departamento de Química-Física, Facultad de Quimica y de Farmacia, Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile
| | - Nancy Gomez-Vierling
- Instituto de Fisica, Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.A.C.); (F.P.-C.); (S.M.); (N.G.-V.); (N.M.); (H.Z.)
- Centro de Investigacion en Nanotecnologia y Materiales Avanzados (CIEN-UC), Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.J.R.); (M.A.S.-A.)
| | - Nicolas Moraga
- Instituto de Fisica, Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.A.C.); (F.P.-C.); (S.M.); (N.G.-V.); (N.M.); (H.Z.)
- Centro de Investigacion en Nanotecnologia y Materiales Avanzados (CIEN-UC), Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.J.R.); (M.A.S.-A.)
| | - Hugo Zelada
- Instituto de Fisica, Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.A.C.); (F.P.-C.); (S.M.); (N.G.-V.); (N.M.); (H.Z.)
- Centro de Investigacion en Nanotecnologia y Materiales Avanzados (CIEN-UC), Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.J.R.); (M.A.S.-A.)
| | - Marco A. Soto-Arriaza
- Centro de Investigacion en Nanotecnologia y Materiales Avanzados (CIEN-UC), Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.J.R.); (M.A.S.-A.)
- Departamento de Química-Física, Facultad de Quimica y de Farmacia, Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile
| | - Tomas P. Corrales
- Departamento de Fisica, Universidad Técnica Federico Santa María, Valparaíso 2390123, Chile;
| | - Ulrich G. Volkmann
- Instituto de Fisica, Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.A.C.); (F.P.-C.); (S.M.); (N.G.-V.); (N.M.); (H.Z.)
- Centro de Investigacion en Nanotecnologia y Materiales Avanzados (CIEN-UC), Pontificia Universidad Catolica de Chile, Santiago 7820436, Chile; (M.J.R.); (M.A.S.-A.)
| |
Collapse
|