Experimental investigation of magneisum based metallic biomaterials

Abstract

Biomaterials are naturally occurring or man-made materials that can be used as an implant inside the human body to support a particular organ or help in the healing of any organ or tissue. Accurate design of any implant is necessary for its proper functioning and improved life. Interaction of implant with human body involves contact with blood, tissues and other body fluids. Under such extreme conditions, understanding the corrosion and biological behaviour of an implant is mandatory. Cardiovascular implants like endovascular stents are used to treat atherosclerosis, where the blood carrying arteries are blocked due to deposition of fat. Deposition puts extra load on the heart, and in extreme cases, it may lead to heart attack and eventual fatality. Balloon angioplasty was the earlier procedure adopted to cure atherosclerosis, but it had its own disadvantages. Stents are very successful in overcoming the problems of restenosis faced by balloon angioplasty by providing suitable support to the arteries. Stents are permanent implants which once placed cannot be removed from the arteries. Therefore, the presence of foreign material in the blood carrying arteries produced problems like thrombus formation and inflammation. Further, restenosis was a significant issue with stents. Hence, biodegradable metals were selected as suitable materials for biodegradable stents. Continuous research in the field of biomaterials has confirmed magnesium and iron as two of the best biodegradable metallic materials. These materials are non-toxic to the body, and the degradation products do not cause any adverse effect on the body. However, magnesium degrade at avery high rate inside the body and iron degrades very slowly. Therefore, controlling the degradation rate of these two materials is a major challenge before the scientific community. Magnesium (Mg) was selected for study in this research experiment. The degradation rate of Mg is controlled with the help of surface modification technique, and Iron (Fe) and Hydroxyapatite (HaP) were selected as the coating material. Physical Vapor Deposition technique was chosen to coat the two materials on Mg substrate newline