Haemolysis Test For Evaluating The Biocompatibiliby Of Austenitic Nickel-free Stainless Steel

ObjectivesAt present,the medical stainless steel used in clinical is 316L including10%-15%.As the nickel ion is a potential allergen factor that may induce toxicity, cell damage and inflammation occurs.It can induce the dangers ofcancer. In view of stainless steel containing nickel could cause harm to human body,in recent years a high nitrogen was developed,content of nickel-free stainless steel,ready for biomedical. Austenitic nickel-free stainless steel has good strength and toughness,good corrosion resistance.But the biological safety must be tested.In this experiment,we make the new medical nickel-free stainless steel(BIOSSN4) into the wafer of 5mmdiameter and lmm thickness.To preliminarily evaluate the biocompatibility of austenitic nickel-free stainless steel with in haemolysis test by measuring haemolysis rate. So this experiment can provide a biological basis for the clinical application.MethodsThe experiment materials:First austenitic nickel-free stainless steel was made into wafers of 5mm diameter and 1mm thickness (1088cm2).Then the mater was put into superclean bench and autoclaved after disinfected and sterilized.The experiment methods:Adult volunteers were clinical randomly selected for blood analysis.Selsct normal red blood cell results 3,signed informed consent.Then the material was put separately in the cuvette with 10ml physiological saline solution as the test group,while those in the cuvette with 10ml distilled water or 10ml physiological solution were taken as the positive control group and the negative control group.The human blood(0.2ml) was added into each cuvette. Haemolysis rate was measured according to the formula of (the absorbance value of austenitic nickel-free stainless steel-the absorbance value of negative control group)/(the absorbance value of positive control group- the absorbance value of austenitic nickel-free stainless steel).ResultsIn this experiment, BIOSSN4 and the negative control group did not appear haemolysis phonomena and the positive control group induced haemolysis phonomena. Haemolysis rate of the austenitic nickel-free stainless steel was 3.831%,which was lower than 5%.ConclusionThe austenitic nickel-free stainless steel will not induce acute haemolysis. And The austenitic nickel-free stainless steel possesses satisfactory biocompatibility.These results provide a biological basis for clinical application...