Abstract: Objective The compound containing gadolinium and hydroxyapatite (HA) were used as raw materials,a novel nano-hydroxyapatite composite scaffold containing gadolinium compound was prepared by chemical synthesis,to provide a new engineering scaffold for cartilage repair in tissue engineering. Methods The hydroxyapatite composite scaffold containing gadolinium compounds was prepared by homogeneous precipitation method, and the cylindrical three-dimensional structure was prepared. The appearance and general morphology of the hydroxyapatite composite scaffold containing gadolinium compounds were evaluated for observation and evaluation, and the porosity and morphological structure were further observed under electron microscopy to see whether the porosity and morphological structure met the experimental requirements. Results The prepared hydroxyapatite composite scaffold containing gadolinium compounds has good appearance, large porosity and large pore structure, which is conducive to bone tissue growth. Under electron microscopy, the pores in the scaffold were honeycomb structures with good mutual connectivity. The hydroxyapatite particles were irregular polygons closely arranged with each other, but micropores were formed between individual particles. The three-dimensional structure of such large pores and micro-pores provides a good scaffold for the proliferation and differentiation of seed cells. Conclusion The hydroxyapatite composite scaffold containing gadolinium compounds prepared in the experiment has a good porosity and a three-dimensional micropore structure with large pore size under the appearance and electron microscopy, but the cytotoxicity of the scaffold and the effects of co-culture on cell proliferation still need further study.

Key words: hydroxyapatite, rare earth element, bone induction, bone repair