Topography characterization and initial cellular interaction of plasma-based Ar⁺ beam-treated PDMS surfaces

• Published in: Journal of applied polymer science Vol. 111; no. 5; pp. 2637 - 2646
• Main Authors: Keranov, I, Vladkova, T.G, Minchev, M, Kostadinova, A, Altankov, G, Dineff, P
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 05-03-2009; Wiley
• Subjects: AFM; Applied sciences; Biological and medical sciences; Coating, metallization, dyeing; cold plasma; Exact sciences and technology; hydrophilic polymers; Machinery and processing; Medical sciences; nanolayers; Plastics; polisiloxanes; Polymer industry, paints, wood; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Technology of polymers; Technology. Biomaterials. Equipments; Cell proliferation; Biological properties; Dimethylsiloxane polymer; Roughness; AFM; Durability; Surface topography; Experimental study; Property processing relationship; Argon ion; Surface treatment; Structure processing relationship; hydrophilic polymers; Reactive ion etching; Wettability; Cold plasma; Cell adhesion; Surface properties; Biocompatibility; Biomaterial; nanolayers; Fibroblast; polisiloxanes
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.29185

Assuming that the existence of an ion-flow in the plasma volume could strength the surface modifying effect, including its durability, a parallel plate reactor in reactive ion etching mode was employed to obtain surface modified PDMS with improved cellular interaction. The discharge power was varied at 100, 1200, and 2500 W to ensure varied ion-flow density. The changes in the surface topography were observed by SEM and AFM, and the surface roughness was characterized by both: mean roughness, Ra, and root-mean-square, Rq. Time dependent water contact angle measurements were performed to control the durability of the hydrophilizing effect. Anisotropic etching, accompanied with decrease of the PDMS surface roughness, was observed up to discharge power of 1200 W that turns in intense isotropic one, accompanied with a sharp increase of the surface roughness over 1200 W, most probably because of arise of reverse sputtered neutrals diffracting the main plasma Ar⁺ flow. Human fibroblasts were applied as an in vitro model to learn more about the initial cellular interaction of the modified surfaces and to identify the optimal treatment conditions.