Preparation Of Poly(Hydroxybutyrate-co-hydroxyoctanoate)Articular Integrative Tissue-engineering Scaffold

Today, Articular cartilage injury and osteoarthritis have become worldwide common and frequently occurring diseases. However, the articular cartilage is a highly specialized organization, which makes joint diseases become difficult to treat. The traditional method for the treatment of articular cartilage injury is a surgical transplant, including autologous cartilage transplantation and allogeneic cartilage transplantation.Transplant surgery has often been successful for the functional restoration of defect tissues, but there are many inadequacies, such as serious shortage of donor, likely to cause secondary damage, allograft immunogenicity. Tissue engineering makes modern medicine step out of the scope of organ transplantation, enter into a new era of organ reconstruction and open up a new way for the treatment of joint diseases. To reconstruct living tissue/organ using tissue engineering techniques, three components, such as cells, signal molecules, and scaffolds. On this basis, tissue culture and organs clone begain.In this paper, we used independent development biodegradable material-Poly(3-hydroxybutyrate-co-3-hydroxyoctanoate)(PHBHOx) as main material and P-tricalciμm phosphate (P-TCP) and acellular matrix (ACTM) as auxiliary materials to prepare.bone-cartilage integrative tissue-engineering scaffold and research its physical and chemical properties and biological characteristics.Firstly, proteoglycans and collagen in extracellular matrix retain structural integrity by improved Courtman. ACTM as an auxiliary material of cartilage layer can provide nutrients for Bone Mesenchymal Stem Cells.The bone-cartilage integrative tissue-engineering scaffolds were prepared with particle-leaching method by using NaCl particles as pore-foaming agent. The macro-structure and internal pore morphology of integrative tissue-engineering scaffold were observed by scanning electron microscopy. The porosity of scaffolds layers were determined by specific gravity method. The mechanical strength of different proportionate composite scaffolds was evaluated in terms of compressive strength by using a universal testing machine. The water absorption test of scaffolds was conducted by weighing method in vitro. The scanning electron microscopy results showed that the cartilage layer/interlayer/bone layer integrative tissue-engineering scaffolds were in a size125±10μm of cartilage layer,30±5μm of interlayer and300±35μm of bone layer and scaffolds porosity were above80%and rich in uniform pores,which was close to ideal aperture of bone-cartilage tissue engineering scaffold.Bone Mesenchymal Stem Cells (BMSCs) of rabbits were isolated and subcultured with whole blood directly separating method in vitro. The growth curve of primary and passaged cells was assaied by MTT and cells morphology observed under the microscope. BMSCs seeded on the cartilage layer/interlayer/bone layer integrative tissue-engineering scaffolds were detected by MTT and observed by scanning electron microscopy.In this paper, we firstly used independent development biodegradable material-Poly(3-hydroxybutyrate-co-3-hydroxyoctanoate)、β-tricalciμm phosphate and acellular matrix to prepare three layers integrative tissue-engineering scaffold. In the course of the study, Created a step-by-step operation and once forming particle-leaching technology and be successful to prepare bone-cartilage integration scaffold for osteochondral tissue engineering research which provide the required technical parameters for the follow-up study of bone-cartilage tissue engineering.