Process for preparing medical 3D chitosan material

Abstract

A process for preparing medical 3-D chitosan material with certain shape used for setting up bone includes such steps as dissolving chitosan in 2% solution of acetic acid, filtering, laying aside forremoving bubbles, coating it on the inner surface of a mould, putting the mould in 3-8% coagulating luqid of sodium hydroxide to obtain a white gel layer used as template for chitosan in site assembling, filling the solution of chitosan in acetic acid into the said template, gradient neutralizing in the coagulating liquid to obtain longitudinal height ordered 3-D chitosan material, immersing in distilled water until it shows neutral, and vacuum drying. It can be used to make bone-setting nail or rod, or splint.

Description

technical field [0001] The invention relates to a preparation method of a three-dimensional chitosan medical material. Background technique [0002] At present, the clinical treatment of fracture surgery mostly uses metal materials such as iron, titanium and cobalt nails, bolts or splints as devices for implanting bones in the body, and patients need to suffer from a second operation. Therefore, an ideal Temporary implantation of controllable biodegradable fracture internal fixation materials is an urgent problem in medical materials. [0003] The biodegradable three-dimensional materials temporarily implanted in the body studied at home and abroad are mainly L-lactic acid (PLLA), polyglycolic acid (PGA) and polydioxanone (PDS). So far, there are only two "temporary stent" products approved for routine clinical use in the United States. One is a self-reinforcing polyglycolic acid stick under the trade name Biofix, and the other is a polydioxanone ...

AI Technical Summary

Problems solved by technology

However, these two products still have many shortcomings in clinical use: 1) These materials are mainly degraded by hydrolysis, and their acidic degradation products can act as autocatalysis, resulting in a rapid decline in the mechanical properties of the material. The degradation rate is difficult to control and cannot be guaranteed. 2) When these materials degrade, they release acidic substances (PGA releases glycolic acid, PLLA releases lactic acid, and PDS releases glyoxylic acid). These acidic substances can easily lead to non-infectious inflammation. 7.9% of the patients treated with the Biofix device had late stage non-infectious inflammatory reactions, which could only be drained by surgery. Therefore, several trauma treatment centers in the United States no longer use the current form of degradable fixation devices; 3) These materials are used in Poor visibility on conventional radiographs and difficult to detect

Therefore, chitosan can meet the basic requirements of biodegradable materials temporarily implanted in the body, but due to the strong hydrogen bonding between chitosan molecules, it is in a tight aggregation structure, which is neither soluble in common solvents nor heated Melting, it is a non-plastic polymer, and it is very difficult to process and shape

Therefore, before the present invention was made, there were no reports of using chitosan to prepare three-dimensional materials at home and abroad so far.