Biophysicochemical evaluation of chitosan-hydroxyapatite-marine sponge collagen composite for bone tissue engineering Ramjee Pallela, 1 Jayachandran Venkatesan, 2 Venkateswara Rao Janapala, 3 Se-Kwon Kim 1,2 1 Marine Bioprocess Research Center, Pukyong National University, Busan 608-737, Republic of Korea 2 Department of Chemistry, Pukyong National University, Busan 608-737, Republic of Korea 3 Toxicology Unit, Biology Division, Indian Institute of Chemical Technology, Hyderabad 500-607, India Received 9 April 2011; revised 13 July 2011; accepted 29 September 2011 Published online 29 November 2011 in Wiley Online Library (wileyonlinelibrary.com). DOI: 10.1002/jbm.a.33292 Abstract: Tricomponent scaffold systems prepared by natural materials especially of marine origin are gaining much attention nowadays for the application in bone tissue engineering. A novel scaffold (Chi-HAp-MSCol) containing chitosan (Chi), hy- droxyapatite (HAp) derived from Thunnus obesus bone and ma- rine sponge (Ircinia fusca) collagen (MSCol) was prepared using freeze-drying and lyophilization method. This biomimetic scaf- fold, along with the Chi and Chi-HAp scaffolds were character- ized biophysicochemically for their comparative significance in bone grafting applications. The structural composition of the chitosan, Chi-Hap, and Chi-HAp-MSCol scaffolds were charac- terized by Fourier Transform Infrared spectroscopy. The poros- ity, water uptake, and retention abilities of the composite scaffolds decreased, whereas Thermogravimetric and Differen- tial Thermal Analyses results revealed the increase in thermal stability in the scaffold because of the highly stable HAp and MSCol. Homogeneous dispersion of HAp and MSCol in chitosan matrix with interconnected porosity of 60–180 lm (Chi-HAp) and 50–170 lm (Chi-HAp-MSCol) was observed by Scanning Elec- tron Microscopy, X-ray diffraction, and optical microscopy. Cell proliferation in composite scaffolds was relatively higher than pure chitosan when observed by MTT assay and Hoechst stain- ing in vitro using MG-63 cell line. These observations suggest that the novel Chi-HAp-MSCol composite scaffolds are promis- ing biomaterials for matrix-based bone repair and bone augmentation. V C 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 100A: 486–495, 2012. Key Words: Ircinia fusca, marine sponge collagen, chitosan, hydroxyapatite, bone tissue engineering How to cite this article: Pallela R, Venkatesan J, Janapala VR, Kim S-K. 2012. Biophysicochemical evaluation of chitosan- hydroxyapatite-marine sponge collagen composite for bone tissue engineering. J Biomed Mater Res Part A 2012:100A:486–495. INTRODUCTION Tissue engineering is an ever expanding field of biomedical arena, especially, bone tissue augmentation and repair by artificial bone material, and their scaffolds are prevalent to replace the damaged or diseased bone. Osteoconductivity and osteoinductivity are the two major parameters for any bone regeneration procedure, through which the newly introduced biomaterial increases the ingrowth of osteopro- genitor cells, capillaries, and perivascular tissue from the recipient bed. 1 Although various artificial substitutes along with the auto and allograft interventions are common nowa- days, however, the limitations like donor search, additional surgery, transmission of dreadful diseases, and expenditure poses a need to develop alternatives to these procedures. 2,3 Hence, the notion of biocompatibility is evolving in conjunc- tion with the continuous development of biomaterials or biomedical devices from natural sources. Chitosan (Chi) has been considerably used as a scaffold in orthopedic and other biomedical applications due to its high biocompatibility, biodegradability, porous structure, suitability for cell ingrowth, and intrinsic antibacterial nature. 4–6 Chi based composite biomaterials of low intercon- nected porosity for cell attachment and optimum mechani- cal strength need to be improved. Hence, instead of single component system that cannot assist and mimic all the properties of natural bone, an alternative multicomponent system has to be developed for bone repair and tissue engineering. Hydroxyapatite [HAp, Ca 10 (PO 4 ) 6 (OH) 2 ] possesses signif- icant biocompatibility in bone, owing to its chemical compo- sition that is similar to bone material. 7 HAp, especially in the form of nanocrystals, has been considered to play an important role in various bone-related applications. 8–10 The composition of chitosan with synthetic HAp is more widely used as a bone grafting substitute. 11 However, natural HAp derived from pig bone combined with chitosan has been investigated by some researchers for bone regeneration. 12,13 In addition, naturally derived HAp are well studied for chi- tosan-hydroxyapatite (Chi-HAp) scaffold generation, which induced significant cell proliferation and biocompatibility. 14 Correspondence to: S-K. Kim; e-mail: sknkim@pknu.ac.kr Contract grant sponsors: Marine Bioprocess Research Centre of the Marine Bio 21 Center, the Ministry of Land, Transport and Maritime, Republic of Korea, Financial support from Department of Biotechnology, Government of India (V.R.J.) 486 V C 2011 WILEY PERIODICALS, INC.