| Background: The cure of bone defect is a difficult problem in surgery. The ultimate obstruct is that the ideal bone surrenal has not been found. The demands are : 1. good compatibility without immunity reaction. 2. the same mechanics strength as human bone. 3. the activity of inducing bone-formation. 4. easy-manufactured 5. being absorbed by host. Until now, we have not found it.Objective: To develop a new degradable hyper-porosity Ca3(PO4)2 bone cells scaffold/NM ZrO2 reinforced.By cooperation with Material academy of Tianjin university and Institute of solid physics of China academy science, we develop a new bone surrenal with advantage of hyper-porosity and compression resistance enhanced by nanometer ZrO2. We call it hyper-porosity Ca3(PO4)2 bone cells scaffold/NM ZrOi reinforced.1. To acquire degradable hyper-porosity Ca3(PO4)2 bone cells scaffold/NM ZrO2 reinforced Method:Medical-grade CaCO3 and CaHPO4-2H2O were used as material to acquire acicular hydroxyapatile ( length /diameter =10) by hot reaction. Then we made namo ZrO2 grain (grain diameter 20-50nm). Next we made thick material liquid with acicular hydroxyapatile and namo ZrO2 grain, immerged polyurethane sponge (porosity 92%, bore diameter 300um) into thick material liquid, wiped off redundant liquid by crushing, then acquired degradable hyper-porosity Ca3(PO4)2 bone cells scaffold/NM ZrO2 reinforce by fritting.Result: Porosity is 75-93%. Pore diameter is 200-450um. Pore distribution is well distributed and linked up. Compressive strength is 2.0Mpa.2. Bone Cells Scaffold/NM ZrO2 biology evaluation Method :1. Cytotoxicity test: This experiment was adopted leach liquid of Bone Cells Scaffold/NM ZrO2 , according to following two plans:(1) Cell shape observational method: put material need to be measure, negativeand positive contrast material into 35mm culture dish, add L-929 cell suspension 3 ml(cell concentration 6 X 104/ml), observe sample border cell shape and growth state through inversion microscope.(2) MTT: Relative Growth Rate (RGR)=( mean of test team A / mean of negative contrast A) X 100%, carry out cytotoxicity grading according to calculated value.2. Acute whole body toxicity test: This experiment was adopted leach liquor of Bone Cells Scaffold/NM ZrO2 being injected through rat tail intravenous. Negative contrast is physiological saline of same lot number, positive contrast is 6.4% carbolic acid. We weighed and observed common state common state, toxicity behave and death at 24h, 48h, 72h after injection.3. Hemolysis test: This experiment adopted leach liquor of Bone Cells Scaffold/NM ZrO2 to measure the degree of rabbit erythrocatalysis and nomadic haemoglobin and to evaluate the hemolysis degree in vitro.Result:1. Cytotoxicity of Bone Cells Scaffold/NM ZrO2 is 0-1 grade.2. The common state of Bone Cells Scaffold/NM ZrO2 team rats was good. There was not observable toxicity behave, body weight increase and death.3. Hemolysis rate of Bone Cells Scaffold/NM ZrO2 is 2.40%. The test did not cause hemolysis in vitro.3. Union culture of MC-3T3E1 with Scaffold/NM ZrO2 Method :The MC-3T3E1 cells were cultured on the scaffold. The growing state and combination ability of cells with scaffold were observed by optical microscope , scaning electron microscope and cells counting respectively.Result: The MC3T3-E1 grew well on the scaffold in either scaffold leaching liquor team or DMEM team. Difference of growth curve was not obvious in the two teams. The condition of attaching and creeping of MC3T3-E1 to the scaffold was well.4. Rabbit primary osteoblast culture Method:1. Rabbit marrow stem cells were cultured in nutrient fluid containing 10mmol/L - glycerine natrium phosphoricum, 10nmol/Ldexamethasone, 50mg/ml vitamin C.2. Osteoblast identificationalkaline phosphatase staining:After cells creeping on cover glass and fixation, alkaline phosphatase staining (Gomori) was performed. Thick brown grain could be seen in the cytoplasm and cell membranes and shade nucleolus even.activity...
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