CN107050524A - 一种新型抗菌复合生物材料的制备方法 - Google Patents

一种新型抗菌复合生物材料的制备方法 Download PDF

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CN107050524A
CN107050524A CN201611204168.XA CN201611204168A CN107050524A CN 107050524 A CN107050524 A CN 107050524A CN 201611204168 A CN201611204168 A CN 201611204168A CN 107050524 A CN107050524 A CN 107050524A
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Abstract

本发明涉及一种新型抗菌复合生物材料的制备方法。所描述的抗菌复合生物材料为羟基磷灰石/壳聚糖/银复合仿生水凝胶材料。首先将壳聚糖用稀醋酸溶液溶解,将β‑甘油磷酸钠(β‑GP,β‑glycerophosphate)溶于三蒸水中,将以上两份溶液置于4℃的冰箱中过夜保存使其稳定,然后在持续搅拌下将羟基磷灰石粉末加入上述壳聚糖溶液中,冰浴,加入β‑GP溶液,pH中性环境下,逐滴加入少量乙二醛(Gl,glyoxal),加入适量纳米银颗粒,搅拌使其混合均匀后,将以上混合溶液在37℃下过夜放置,形成水凝胶,将制备好的水凝胶保存于4℃的冰箱中,即得羟基磷灰石/壳聚糖/银复合仿生水凝胶材料。本发明所提供的新型羟基磷灰石/壳聚糖/银复合仿生水凝胶材料克服了现有的骨修复材料在需要快速进行骨骼填充、骨组织修复部位环境复杂,或需要进行微创骨修复治疗时的应用局限性,其制备方法工艺简单、成本低廉、合成安全,对于生物医学工程领域具有重要应用价值。

Description

一种新型抗菌复合生物材料的制备方法
技术领域
本发明涉及一种新型抗菌复合生物材料的制备方法,特别是一种羟基磷灰石/壳聚糖/银复合仿生水凝胶材料的制备方法。
背景技术
应用于生物医学工程的抗菌材料,要求其组成要能够与生物组织的组成尽可能接近,羟基磷灰石(HA,Ca10(PO4)6(OH)2)是生物体内硬组织的主要成分,具有良好的生物相容性和生物活性,目前在临床医学上,已被广泛应用于骨组织的修复与替代。如能将羟基磷灰石与抗菌剂结合制成复合材料,将会有效地减少在骨移植以及骨修复过程中所容易伴随发生的感染现象。在抗菌剂方面,有着良好抗菌性能的金属银及银离子广受关注,金属银及银离子的相关化合物一般是通过阻碍微生物的相关酶的合成、干扰其DNA的结合以及破坏微生物的蛋白质组成或细胞膜成分、破坏微生物的呼吸以及电子迁移等方式来起到杀菌作用的。壳聚糖是由甲壳素经N-脱乙酰化处理后得到,是目前发现的惟一天然碱性多糖,具有良好的生物降解性和生物相容性,而且还具有选择性促进表皮细胞生长、促进骨组织修复的独特的生物活性。目前,针对磷酸钙/壳聚糖复合生物陶瓷材料以及三维支架材料的研究较多,但当临床中遇到需要快速进行骨骼填充、骨组织修复部位环境复杂,或需要进行微创骨修复治疗时,以上材料就有了应用局限性,如能将羟基磷灰石、壳聚糖和银结合起来制备成复合仿生水凝胶,则可以克服以上缺点,得到可适应复杂骨修复环境的、适宜微创手术应用的新型抗菌复合生物医学材料。
发明内容
本发明的目的是为了克服现有的磷酸钙/壳聚糖型复合生物医学材料的应用局限性,提供一种简单有效的新型羟基磷灰石/壳聚糖/银复合仿生水凝胶材料的制备方法。
按照本发明提供的技术方案,首先将壳聚糖用一定浓度的稀醋酸溶液溶解,将β-甘油磷酸钠(β-GP,β-glycerophosphate)溶于适当的三蒸水中,将以上两份溶液置于4℃的冰箱中过夜保存使其稳定,然后在持续搅拌下将适当量的羟基磷灰石粉末加入上述壳聚糖溶液中,冰浴,加入适当浓度的β-GP溶液,pH中性环境下,逐滴加入少量乙二醛(Gl,glyoxal),加入适量纳米银颗粒,搅拌并使其混合均匀,将以上混合溶液在37℃下过夜放置,形成水凝胶,将制备好的水凝胶保存于4℃的冰箱中。
本发明涉及一种新型羟基磷灰石/壳聚糖/银复合仿生水凝胶的制备方法,采用了以下技术方案:
1、配制壳聚糖溶液:将壳聚糖按照一定比例溶于一定浓度的稀醋酸溶液中,混合均匀,将所得溶液置于4℃的冰箱中过夜保存使其稳定;
2、配制β-甘油磷酸钠溶液:将β-甘油磷酸钠(β-GP,β-glycerophosphate)溶于适当的三蒸水中混合均匀,将所得溶液置于4℃的冰箱中过夜保存使其稳定;
3、制备羟基磷灰石/壳聚糖混合溶液:在持续搅拌下将适当量的羟基磷灰石粉末加入上述第一步中的壳聚糖溶液中,充分搅拌一定时间,使其混合均匀;
4、羟基磷灰石/壳聚糖/银复合仿生水凝胶的制备:冰浴的情况下,向上述第三步的β-磷酸三钙/壳聚糖混合溶液中加入上述第二步中的适当浓度的β-GP溶液,pH中性环境下,逐滴加入少量乙二醛(Gl,glyoxal),加入适当量纳米银颗粒,搅拌使其混合均匀后,将以上混合溶液在37℃下过夜放置,形成水凝胶;
5、将上述第四步中所得到的水凝胶贮存于4℃的冰箱中,即可得到新型羟基磷灰石/壳聚糖/银复合仿生水凝胶材料。
本发明所提供的新型羟基磷灰石/壳聚糖/银复合仿生水凝胶材料的制备方法克服了现有的骨修复材料在需要快速进行骨骼填充、骨组织修复部位环境复杂,或需要进行微创骨修复治疗时的应用局限性,本制备方法工艺简单、成本低廉、合成安全,对于生物医学工程领域具有重要应用价值。
具体实施方式
下面结合具体实施例对本发明作进一步说明。
一种新型羟基磷灰石/壳聚糖复合仿生水凝胶材料的制备方法,采用以下工艺步骤:
1、配制壳聚糖溶液:将壳聚糖按照1.0~2.0%(w/v)的比例溶于1.0~1.5%(v/v)的稀醋酸溶液中,混合均匀,将所得溶液置于4℃的冰箱中过夜保存使其稳定;
2、配制β-甘油磷酸钠溶液:将β-甘油磷酸钠(β-GP,β-glycerophosphate)0.5~0.7mol溶于4~7mL三蒸水中混合均匀,将所得溶液置于4℃的冰箱中过夜保存使其稳定;
3、制备羟基磷灰石/壳聚糖混合溶液:在持续搅拌下将1.0~2.0%(w/w)的羟基磷灰石粉末加入上述第一步中的壳聚糖溶液中,充分搅拌一定时间,使其混合均匀;
4、羟基磷灰石/壳聚糖/银复合仿生水凝胶的制备:冰浴的情况下,向上述第三步的羟基磷灰石/壳聚糖混合溶液中加入上述第二步中的β-GP溶液,pH中性环境下,逐滴加入0.7~1.0mL乙二醛(Gl,glyoxal),加入4.0~5.0%(w/w)纳米银颗粒,搅拌使其混合均匀后,将以上混合溶液在37℃下过夜放置,形成水凝胶;
5、将上述第四步中所得到的水凝胶贮存于4℃的冰箱中,即可得到新型羟基磷灰石/壳聚糖/银复合仿生水凝胶材料。

Claims (2)

1.一种新型抗菌复合生物材料的制备方法,特别是一种羟基磷灰石/壳聚糖/银复合仿生水凝胶材料的制备方法,其特征是:所述材料为羟基磷灰石/壳聚糖/银复合仿生水凝胶材料。先将壳聚糖用一定浓度的稀醋酸溶液溶解,将β-甘油磷酸钠(β-GP,β-glycerophosphate)溶于适当的三蒸水中,将以上两份溶液置于4℃的冰箱中过夜保存使其稳定,然后在持续搅拌下将适当量的羟基磷灰石粉末加入上述壳聚糖溶液中,冰浴,加入适当浓度的β-GP溶液,pH中性环境下,逐滴加入少量乙二醛(Gl,glyoxal),加入适量纳米银颗粒,搅拌使其混合均匀后,将以上混合溶液在37℃下过夜放置,形成水凝胶,将制备好的水凝胶保存于4℃的冰箱中,即可得到新型羟基磷灰石/壳聚糖/银复合仿生水凝胶材料。
2.如权利要求1所述的新型羟基磷灰石/壳聚糖/银复合仿生水凝胶材料的制备方法,采用以下工艺步骤:
(1)、配制壳聚糖溶液:将壳聚糖按照1.0~2.0%(w/v)的比例溶于1.0~1.5%(v/v)的稀醋酸溶液中,混合均匀,将所得溶液置于4℃的冰箱中过夜保存使其稳定;
(2)、配制β-甘油磷酸钠溶液:将β-甘油磷酸钠(β-GP,β-glycerophosphate)0.5~0.7mol溶于4~7mL三蒸水中混合均匀,将所得溶液置于4℃的冰箱中过夜保存使其稳定;
(3)、制备羟基磷灰石/壳聚糖混合溶液:在持续搅拌下将1.0~2.0%(w/w)的羟基磷灰石粉末加入上述第一步中的壳聚糖溶液中,充分搅拌一定时间,使其混合均匀;
(4)、羟基磷灰石/壳聚糖/银复合仿生水凝胶的制备:冰浴的情况下,向上述第三步的羟基磷灰石/壳聚糖混合溶液中加入上述第二步中的β-GP溶液,pH中性环境下,逐滴加入0.7~1.0mL乙二醛(Gl,glyoxal),加入4.0~5.0%(w/w)纳米银颗粒,搅拌使其混合均匀后,将以上混合溶液在37℃下过夜放置,形成水凝胶;
(5)、将上述第四步中所得到的水凝胶贮存于4℃的冰箱中,即可得到新型羟基磷灰石/壳聚糖/银复合仿生水凝胶材料。
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