Biomimetic nanostructures for the silicone-biosystem interface: tuning oxygen-plasma treatments of polydimethylsiloxane

Osmani, B., Gerganova, G. and Müller, B. (2017) Biomimetic nanostructures for the silicone-biosystem interface: tuning oxygen-plasma treatments of polydimethylsiloxane. European Journal of Nanomedicine, 9(2), pp. 69-77. (doi: 10.1515/ejnm-2017-0002)

Abstract

Polydimethylsiloxanes (PDMS) have drawn attention because of their applicability in medical implants, soft robotics and microfluidic devices. This article examines the formation of dedicated nanostructures on liquid submicrometer PDMS films when exposed to oxygen-plasma treatment. We show that by using a vinyl-terminated PDMS prepolymer with a molecular weight of 800 g/mol, one can bypass the need of solvent, copolymer, or catalyst to fabricate wrinkled films. The amplitude and periodicity of the wrinkles is tuned varying the thickness of the PDMS film between 150 and 600 nm. The duration of the plasma treatment and the oxygen pressure determine the surface morphology. The amplitude was found between 30 and 300 nm with periodicities ranging from 500 to 2800 nm. Atomic force microscopy was used to measure film thickness, amplitude and wrinkle periodicity. The hydrophobic recovery of the nanostructured PDMS surface, as assessed by dynamic contact angle measurements, scales with nanostructure’s fineness, associated with an improved biocompatibility. The mechanical properties were extracted out of 10,000 nanoindentations on 50×50-μm2 spots. The mechanical mapping with sub-micrometer resolution reveals elastic properties according to the film morphology. Finally, we tailored the mechanical properties of a 590±120-nm-thin silicone film to the elastic modulus of several MPa, as required for dielectric elastomer actuators, to be used as artificial muscles for incontinence treatments.

• Item Type: Articles
• Keywords: Dielectric elastomer actuators, dynamic contact angle measurements on PDMS, local mechanical properties of thin polymer films, nanometer-thin polymer films, oxygen-plasma-tuned wrinkles.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Gerganova, Gabriela
• Authors: Osmani, B., Gerganova, G., and Müller, B.
• Subjects: Q Science > Q Science (General); Q Science > QC Physics; Q Science > QD Chemistry
• College/School: College of Medical Veterinary and Life Sciences
• Journal Name: European Journal of Nanomedicine
• Journal Abbr.: Eur. J. Nanomed.
• Publisher: De Gruyter
• ISSN: 1662-596X
• ISSN (Online): 1662-596X
• Published Online: 01 April 2017
• Copyright Holders: Copyright © 2017 Walter de Gruyter GmbH
• First Published: First published in European Journal of Nanomedicine 9(2): 69-77
• Publisher Policy: Reproduced in accordance with the publisher copyright policy