F. Ibrahim, N.A. Abu Osman, J. Usman and N.A. Kadri (Eds.): Biomed 06, IFMBE Proceedings 15, pp. 680-683, 2007 www.springerlink.com © Springer-Verlag Berlin Heidelberg 2007 ---------------------------------------------------------------- IFMBE Proceedings Vol. 15 --------------------------------------------------------------- Characterization of Collagen/PEO 600K for Tissue Engineering Scaffold N.F. Mohd Nasir 1 , S.I. Sahidan 2 , M. Rampado 2 , M.G. Raha 2 , N.A. Kadri 2 , N. Mohd. Zain 2 1 Biomedical Electronics Engineering Program, School of Mechatronics, Northern Malaysia University College of Engineering, Kangar, Malaysia 2 Department of Biomedical Engineering, Faculty of Engineering, University Malaya, Kuala Lumpur, Malaysia Abstract— In this study, a new material which is collagen/ poly (ethylene oxide) (PEO) blend was developed to determine its possibility as a promising material for tissue scaffold. PEO with average molecular weight of 600,000 and collagen origi- nated from calf skin were dispersed in 0.1 M acetic acid to prepare a concentration of 1 wt% for PEO and 0.15 wt% for collagen. The collagen-PEO600K blend film was then obtained by solution casting method. The morphology and the phase structure of the blends were studied using SEM and XRD. SEM results shown that by having certain ratio of collagen and PEO, the membrane began to developed porous structures which are possible to assist tissue attachment on the scaffold. The X-ray diffractograms demonstrate PEO 600K influences on the blend thus enhancing crystallinity of collagen which explained the membrane morphological structure. Therefore, we concluded that the crystallinity of PEO in the blend is cru- cial to produce desirable morphological structure of the mem- brane which is required for a reliable tissue scaffold. Keywords— collagen, PEO, tissue scaffold, SEM, XRD I. INTRODUCTION Collagen is readily available, non-toxic and has the fibril architecture in natural tissues. Thus, collagen provides an excellent basis for biomaterials, such as arterial prostheses and artificial skin [1, 2]. The main amino acids in collagen are glycine, proline, hydroxypropline and alanine. The or- dered triple helical structure of collagen is stabilized by both interchain hydrogen bonds and by structural water molecules [3-7]. Collagen can be desorbed into the body, is non-toxic, in- duces only minimal immune response (even between differ- ent species), and is excellent for attachment and biological interaction with cells. Collagen may also be processed into a variety of formats, including porous sponges, gels, and sheets, and can be cross linked with chemicals to make it stronger or to alter its degradation rate [8]. Collagen and PEO do not exist together as blends in na- ture, but specific properties of each may be used to produce synthetic blends that make unique structure and mechanical properties. The miscibility of PEO and collagen with other synthetic polymers and the properties of the blends have been studied previously [9]. However, specific study which directed to develop a product from this material has not been carried out yet. Thus, this study is aiming to produce scaffold for tissue engineering application. An ideal scaffold should possess following characteristics for desirable biologic response [5]: (i) three-dimensional and highly porous with an intercon- nected pore network for cell/tissue growth and flow trans- port of nutrients and metabolic waste, (ii) biodegradable or bioresorbable with a controllable degradation and resorption rate to match cell/tissue growth in vitro and/or in vivo, (iii) suitable surface chemistry for cell attachment, proliferation and differentiation, (iv) mechanical properties to match those of tissues at the site of implantation, and (v) be easily processed to form a variety of shapes and sizes [10]. Therefore, we intend to correlate the membrane surface to their phase structure of collagen/PEO blend membranes which is important in developing a tissue scaffold. This objective is hoped to be achieved through the characterization of the colla- gen/PEO blend membranes using Scanning Electron Micros- copy (SEM) and X-Ray Diffraction (XRD) techniques. II. MATERIALS AND METHODS Preparation of Collagen, PEO and Collagen/PEO Blend Membranes: Collagen, PEO and collagen/PEO blend mem- branes were prepared by solution cast method. Collagen (calf skin) from Sigma Aldrich and PEO of molecular weight of 600,000 (Fluka) were dispersed in 0.1 M acetic acid aqueous solution to have a concentration of 0.15wt% for collagen and 1wt% for PEO. The solutions were con- tinuously stirred with a magnetic stirrer for about 1 hour at room temperature. Blends were prepared by mixing both polymers in 4 different ratios: 1:0, 1:1, 3:1, and 0:1. Table 1 Ratio of Samples Collagen Poly(ethylene oxide) 1 0 1 1 3 1 0 1