| BCP bioactive ceramic (BCP) have excellent biocompactivity and unique controllable degradation property. It becomes the hotspot of the researchers in biomaterial area. But, BCP has instinct drawbacks that it has high elastic modulus, low toughness and it is brittle. And its compressive strength decreases rapidly when it is prepared to high porous scaffolds. These limit its application in clinical applications of orthopaedics. Many researches predict that the use of composite can give full play to advantages of each component, and offset the disadvantages. This method can make an ideal tissue engineering material.In this paper, d-HA was prepared by chemical precipitation method. Green body was obtained by die-press in own made figuring machine after mixed the powder with porogen. Porous BCP scaffolds obtained by sintering at 1050℃for 2h. Composite scaffolds were made by immersing the BCP scaffolds in PLA solution at low vacuum. After dried, a porous nano d-HA/PLA/BCP composite was prepared, which's structure had the characteristic of the artificial bone. Composite scaffolds were soaked in PBS and SBF to study the changes of pH value, mass, porosity and compressive strength. The bone-like apatite precipitation was also studied.Effect of pH on d-HA and its Ca/P mole ratio was studied in the paper. d-HA powder was gained when pH between 7.2 and 8.2. Ca/P varied with pH, it increased with the increasing of pH. Porogen proportion had effect on porosity, water absorption and compressive strength of scaffolds. When porogen reached 66.7% (mass fractions) in green body, scaffolds had high porosity about 78%, water absorption about 50%, and compressive strength about 1.95 MPa. SEM indicated that pores in scaffolds were integrated and interconnective, proe distribution was homogeneous, and diameter of big hole was 400-600μm.Compressive strength improved after compositing with PLA, and porosity decreased littlie. PLA coating on pore surface is homogeneous, and pore structure and diameter of pore had little change. Interconnective structure remained. Nano d-HA/PLA/BCP composite had higher water absorption then PLA/BCP, closed to BCP scaffolds. And its pore morphology and pore diameter was same to PLA/BCP. But the pore surface was rougher than that of PLA/BCP. This tough surface had something to do with the adhesion of cell. SBF soaking experiment showed nano d-HA/PLA/BCP porous composite scaffolds had more bone-like apatite precipitation. It was found in PBS degradation experiment that nano d-HA could efficiently neutralize acid resulting from PLA degradation.After degradation, porosity had little change and strength decreased slowly. After 4 month, the scaffold's strength was 3MPa, decreased about 24.1%.In general, the method that composite PLA with as-sintered BCP porous scaffolds is a rapid, practical method and satisfied with the tissue engineering need. PLA can improve toughness and strength of scaffolds effectively, and remain the strength of scaffold in degradation. In this paper, nano d-HA is first induced in the porous PLA/BCP composite to have good water absorption and bone-like apatite forming ability. Nano d-HA/PLA/BCP porous composite scaffolds can match the need of tissue engineering. And it will have the widely application value.
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