Study Of Biodegradable AZ31B Magnesium Alloy By Ames Test

As a degradable biomaterial for osteosynthesis, magnesium alloys provide potential advantages for patients with bone fractures or defects due to a good biocompatibility and a high primary stability. Cautery will occurrence when the alloys are put into the humor, the cautery will lead to cytotoxicity, hypersensitiveness, and even canceration. So the international Organization for Standardization make out the standardization that a serial of study and research must be finished before the alloys were used in the human body, which can give the judgement of their biocompatibility. On the basis of ISO correlated standardization, leaching liquor of biodegradable AZ31B magnesium alloy was made out to progress Salmonella typhimurium reverse mutation assay(Ames test) in this study. And the purpose of this study was to answer the question whether the biodegradable AZ31B magnesium alloy had potential mutagenicity and carcinogenicity.Methods1. Appreciation of stain genetic determinantSix stain genetic determinant experiments include: the requirement of histidine, discrepancy of lipopolysaccharides barrier, repair-deficiency of DUV, test of anti-AMP, test of anti-TCN and spontaneous reverse assay were carried out. After the appreciationof stain genetic determinant, incubation at 37℃, make bacterium fluid density to l-3×10~9/ml.2. Nutrient medium Four kinds of nutrient mediums were made reference to Salmonella typhimunum reverse mutation assay.3. Activation systemS-9 and S-9mix were made reference to Salmonella typhimurium reverse mutation assay.4. Design of dosageClean the sample alloy plate with alcohol and supersonic, sterilizing, use normal sodium as diffusion medium, in accordance with GB/T16886.12-2000, establish standard leaching (liquorstock suspension) by means of diprosopia surface area/ diffusion medium is 3cm~2 /ml. 1/2, 2 and 4 times of liquorstock suspension were prepared. 121℃, 1h diffused.5. Salmonella typhimurium reverse mutation assayIn the flat-plate incorporation test of Salmonella typhimurium, the average number of spontaneous revertants of TA97, TA98, TA100, TA102 under 4 concentrations was calculated after incubation at 37℃for 48 hours.ResultsThe number of induced revertants when compared to that of spontaneous revertants was not reproducibly higher in a dose-related manner. The result of Ames test for biodegradable AZ31B magnesium alloy was negative.ConclusionIt implies biodegradable AZ31B magnesium alloy has no potential mutagenicity.