Most important

Polymer composites for medical application

Полимерные композиционные материалы медицинского назначения
Total joint replacement is one of the most common areas of implantology. The materials of joint prosthesis must operate under variable loads for a long time. The proposed composite material based on ultrahigh molecular weight polyethylene (UHMWPE) and the aluminum oxide nanoparticles can significantly improve the tribological characteristics of the material without the traditional radiation crosslinking, leading to oxidative degradation of the polymer, thereby reducing the wear of the friction of endoprosthesis made of such material, which leads to an increase in “life” of the prosthesis. The developed method for processing of the polymer reduces the amount of fusion defects, and thereby increase the durability of the implant material. The resulting composite material has a Young's modulus in compression of 1.5 GPa, and high impact strength, high durability (wear is reduced in 3 times), low friction (coefficient of friction 0.06 in water ) and high biocompatibility. This material has a high resistance to degradation by radiation sterilization up to 55 Mrad and in an oxidizing environment. There are no signs of inflammation, abscesses, as well as the degradation of the material during implantation into the knee joint of laboratory animals. UHMWPE / hydroxyapatite system was chosen to solve the problem of bone defects replacement. Hydroxyapatite (HA) is a bioactive ceramic, which actively contacts with healthy bone tissue, stimulates cell growth and restoration of bone, and acts as a source of calcium and phosphorus. Enhanced biocompatibility of the filler at a high concentration in the matrix will increase the biocompatibility of the composite. Currently biocompatible composite materials based on UHMWPE with concentration of HA in 50 wt. % are produced. At such high concentrations of bioactive ceramics the compressive yield strength increases of 37 %, modulus of 100 %, coefficient of dry friction of 0.14, and wear resistance increases in 2 times. UHMWPE is a promising material for tissue engineering to repair bone defects. Such materials have high requirements to the structure. Implants must have an open-through pores. The number and size of pores depends on the reparative properties of the implant. At the moment, the technology of producing UHMWPE-composite materials with wide range of quantity and size of pores is developed in the in the Center of composite materials. Laboratory samples of a two-layer implants were obtained. The first layer is a porous UHMWPE. The second layer is made of UHMWPE/HAP with a continuous structure to provide the necessary strength of implant. Regenerative medicine also requires the creation and use of new classes of bioresorbable materials with high mechanical characteristics, with a biological activity and promote the restoration of bone defects with complete resorption in non-toxic components. Bioresorbable polymeric material for bone implants were obtained. Polyhydroxybutyrate (PHB) with increased adaptation to bone was used as the polymer matrix to create a composite material. High porosity of the material (50-60 % vol.) and pore size (200-350 microns) allow cells to penetrate into the implant and remain on the surface. This material has the required mechanical properties for the implant. Material can be replaced with bone tissue. In this case, an implantable composite originally played the role of supporting and guiding element that promotes the growth of bone tissu , and later gradually resolved. The material shows a high rate of resorption: surface area of the implant is reduced by 49% after 29 days. The developed material has increased regenerative properties and is non-toxic to the body. If implanted into the bone defect material showing signs neoosteogeneza throughout the area of implantation , the germination of the connective tissue fibers , the injected blood vessels. Biomedical research is performed in N.N. Blokhin Russian Cancer Research Center of RAMS.


Industry Solutions

MEDICINE

Publications

Our contacts

Research group

Doctor of Science, professor
Ph.D., associated professor
Ph.D., engineer
Ph.D., engineer


Back to list




Our projects
Last comments



Яндекс.Метрика