Preparation method of medical grade α-calcium sulfate hemihydrate

Abstract

The invention relates to a preparation method of medical grade alpha-calcium sulfate hemihydrate, the preparation method includes the following steps: a solution preparation step, to be more specific, pouring a calcium salt solution and a sulfate solution into a reaction vessel for mixing evenly, then adding a complex crystal modifier prepared from sodium citrate, aluminum sulfate and succinic acid to obtain a mixed solution; a hydrothermal reaction step, to be more specific, adjusting the mixed solution pH to 3-7, thermostatically heating with stirring for a hydrothermal reaction to produce the alpha-calcium sulfate hemihydrate; a washing and suction filtration step, to be more specific, washing the alpha-calcium sulfate hemihydrate with hot water for 2 ~ 3 times, then using absolute ethanol for termination of the alpha-calcium sulfate hemihydrate hydration process, and immersing for 1 ~ 10min for rapid suction filtration; a drying step; and a gradation optimization step, to be more specific, screening the ground and dried alpha-calcium sulfate hemihydrates into three kinds of powder with different particle size ranges, fully mixing the screened powder, and sealing for packing. According to the preparation method, under normal pressure hydrothermal conditions, the alpha-calcium sulfate hemihydrates is obtained by direct reaction in a water solution, the method is simple, high in production efficiency and low in cost, and the obtained powder has good biocompatibility.

Description

technical field [0001] The invention relates to the technical field of medical implant materials, in particular to a method for preparing medical grade α-calcium sulfate hemihydrate. Background technique [0002] Fractures, bone defects, and bone tumors are one of the most common clinical diseases, and they are on the rise with the increase in traffic accidents, bone degenerative diseases in the elderly population, and plastic surgery. The traditional method uses autologous bone or allogeneic bone for graft repair, but the source is limited and it is difficult to meet the needs of use. This also promotes the extensive research and application of artificial bone repair materials such as calcium phosphate, calcium sulfate, and acrylic. [0003] Calcium Sulfate (Calcium Sulfate) has been used in the field of clinical bone filling repair for more than 100 years. A large number of basic research and clinical applications have confirmed that calcium sulfate has good biocompatibil...

AI Technical Summary

Problems solved by technology

Chinese Invention Patent Application No. 200610029067.3 discloses that chemically pure calcium sulfate dihydrate is used as raw material to prepare alpha calcium sulfate hemihydrate powder by autoclaving, but the equipment required by this method is relatively complicated and the production cost is high

China Invention Patent Application No. 201110123932.1 discloses that amorphous calcium sulfate is used as a raw material, and a high-pressure hydrothermal reaction method is adopted. The reaction temperature is 110~140°C, the reaction time is 6-18h, and after filtration, it is blown and dried at 105~125°C for 6~8h. Produce α-calcium sulfate hemihydrate, however, this method takes too long to react, and the obtained α-calcium sulfate hemihydrate crystal has a relatively large length and diameter, which is not suitable for medical bone repair implant materials

Atmospheric pressure salt solution method is a relatively novel method for preparing α-calcium sulfate hemihydrate at present. The Chinese invention patent application No. 03142607.7 discloses a process for producing α-hemihydrate desulfurized gypsum by atmospheric pressure salt solution method. However, there is no See the report that adopts normal pressure saline solution method to prepare medical grade α-calcium sulfate hemihydrate

The above several methods also all have complex reaction equipment, need to use calcium sulfate dihydrate as raw material, and the purity and crystal size of the obtained α-calcium sulfate hemihydrate are not suitable for use as medical implant bone repair materials.

[0005] Guan Baohong et al. used microemulsion method to prepare medical grade α-calcium sulfate hemihydrate, which synthesized α-calcium sulfate hemihydrate with sulfuric acid and calcium chloride as raw materials , however, the operation process of this method is relatively cumbersome (Colloids and Surfaces A(2012) 88–93)

Xiang Lan et al. used sodium sulfate and calcium chloride as raw materials to prepare α-calcium sulfate hemihydrate whiskers by a pressurized hydrothermal method. This method is simple and practical, and the cost is low, but the obtained α-calcium sulfate hemihydrate has a long diameter The ratio is too large, and the purity is not high, and there is still a gap between the requirements for medical implant bone repair materials (Particuology 8(2010) 240–244)