[Preparation of chitosan-encapsulated porous calcium polyphosphate bioceramic]

To investigate the preparation of a chitosan-encapsulated porus calcium polyphosphate (CPP) bioceramic so as to provide a feasible approach to repair of the bone defect.

The chitosan microspheres were produced by chemical procedures. The CPP bioceramic was made by the following steps: annealing, ball milling, admixing, and calcinating. The chemical method was used to encapsule the calcinated bioceramic by the porus chitosan film. The physicochemical property, biomechanical property, and toxicity of the chitosan-encapsulated porus CPP bioceramic were analyzed.

The uniform holes were observed in the CPP bioceramic under a microscope. The diameter of the hole was 100-300 microm. The chitosan microballoons were amber in color. The particles were uniform with a diameter of 200-400 microm, with a poor compressive strength. They could be easily ground by hand. The maximally tolerated dose of the CPP bioceramic leaching liquor given to the Jimpy mice of both sexes was >24 g/kg on average. The compressive strength reached 200 MPa, and the interval porosity was about 60%-80%, which could completely meet with the compressive strength of the bone substitute.

The chitosan-encapsulated porous CPP bioceramic can be used as a good porous bioceramic scaffold material, which has a good biomechanical property with no acute toxicity, and so may be used as an excellent material for the bone substitute.