Surface characterization of collagen/elastin based biomaterials for tissue regeneration J. Skopinska-Wisniewska a, *, A. Sionkowska a , A. Kaminska a , A. Kaznica b , R. Jachimiak b , T. Drewa b a Faculty of Chemistry, Nicolaus Copernicus University, Gagarin 7, 87-100 Torun, Poland b Collegium Medicum, Nicolaus Copernicus University, Karlowicz 24, 85-092 Bydgoszcz, Poland 1. Introduction Connective tissue is one of the most important tissues of vertebrate’s. It ensures a support of most organs. It is also responsible for connection and protection of different tissues. There are many different types of connective tissue, which have diverse properties and play different roles in bodies. However, they always consist of different types of cells and extracellular matrix (ECM). The main components of ECM are ﬁbrous proteins — collagen and elastin [1,2]. Their mechanical properties are complementary and give the tissues strength and elasticity. The proteins undergo changes and ageing during the life. These processes affect the functionality and properties of tissues and organs. Sometimes it is necessary to replace the tissue that has been destroyed. The perfect material for this purpose is imitation of tissue, with similar mechanical, chemical and biological properties. For this reason it is very important to ﬁnd a method of using parts of ECM, e.g. collagen and elastin, as components of biomaterials. Nowadays collagen is considered as one of the most useful biomaterial. It is hydrophilic, exhibits low antigenicity, low inﬂammatory and cytotoxic responses, good hemostatic properties and controllable biodegradability. It could be shaped in various forms, e.g. ﬁlms, discs, sponges, hydrogels and powder [3]. This multitude of easily available collagen materials makes possible its use as a drug and gene delivery systems [4–6], wound dressings Applied Surface Science 255 (2009) 8286–8292 ARTICLE INFO Article history: Received 21 November 2008 Received in revised form 28 May 2009 Accepted 28 May 2009 Available online 6 June 2009 Keywords: Collagen Elastin Surface modiﬁcation UV-irradiation ABSTRACT Collagen and elastin are the main proteins of extracellular matrix. Collagen plays a crucial role in tensile strength of tissues, whereas elastin provides resilience to many organs. Both biopolymers are readily available and biocompatible. These properties point out that collagen and elastin are good components of materials for many potential medical applications. The surface properties of biomaterials play an important role in biomedicine as the majority of biological reactions occur on the surface of implanted materials. One of the methods of surface modiﬁcation is UV-irradiation. The exposition of the biomaterial on ultraviolet light can alterate surface properties of the materials, their chemical stability, swelling properties and mechanical properties as well. The aim of our work was to study the surface properties and biocompatibility of new collagen/elastin based biomaterials and consideration of the inﬂuence of ultraviolet light on these properties. The surface properties of collagen/elastin based biomaterials modiﬁed by UV-irradiation were studied using the technique of atomic force microscopy (AFM) and contact angle measurements. On the basis of the results the surface free energy and its polar component was calculated using Owens–Wendt method. To assess the biological performance of ﬁlms based on collagen, elastin and their blends, the response of 3T3 cell was investigated. It was found that the surface of collagen/elastin ﬁlm is enriched in less polar component — collagen. Exposition on UV light increases polarity of collagen/elastin based ﬁlms, due to photooxidation process. The AFM images have shown that topography and roughness of the materials had been also affected by UV-irradiation. The changes in surface properties inﬂuence on interaction between the material’s surface and cells. The investigation of 3T3 cells grown on ﬁlms based on collagen, elastin and their blends, leads to the conclusion that higher content of elastin in biomaterial promotes the cell adhesion and their viability on the surface. Also the suitable dose of UV light (1, 2 h) improves the biocompatibility of the materials. ß 2009 Elsevier B.V. All rights reserved. * Corresponding author. Tel.: +48 056 611 49 38; fax: +48 056 654 24 77. E-mail address: joanna@chem.uni.torun.pl (J. Skopinska-Wisniewska). Contents lists available at ScienceDirect Applied Surface Science journal homepage: www.elsevier.com/locate/apsusc 0169-4332/$ – see front matter ß 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.apsusc.2009.05.127