CN1792779A - 一种可生物降解的磷酸三钙纳米粉体的制备方法 - Google Patents
一种可生物降解的磷酸三钙纳米粉体的制备方法 Download PDFInfo
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- QORWJWZARLRLPR-UHFFFAOYSA-H tricalcium bis(phosphate) Chemical compound [Ca+2].[Ca+2].[Ca+2].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O QORWJWZARLRLPR-UHFFFAOYSA-H 0.000 title claims abstract description 40
- 239000001506 calcium phosphate Substances 0.000 title claims abstract description 23
- 239000011858 nanopowder Substances 0.000 title claims abstract description 17
- 229910000391 tricalcium phosphate Inorganic materials 0.000 title claims abstract description 14
- 235000019731 tricalcium phosphate Nutrition 0.000 title claims abstract description 14
- 229940078499 tricalcium phosphate Drugs 0.000 title claims abstract description 14
- 238000004519 manufacturing process Methods 0.000 title abstract description 3
- 239000011575 calcium Substances 0.000 claims abstract description 19
- DLYUQMMRRRQYAE-UHFFFAOYSA-N tetraphosphorus decaoxide Chemical compound O1P(O2)(=O)OP3(=O)OP1(=O)OP2(=O)O3 DLYUQMMRRRQYAE-UHFFFAOYSA-N 0.000 claims abstract description 16
- 238000000034 method Methods 0.000 claims abstract description 15
- ZCCIPPOKBCJFDN-UHFFFAOYSA-N calcium nitrate Chemical compound [Ca+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O ZCCIPPOKBCJFDN-UHFFFAOYSA-N 0.000 claims abstract description 12
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 9
- 238000002360 preparation method Methods 0.000 claims abstract description 9
- 239000002270 dispersing agent Substances 0.000 claims abstract description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 5
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 claims abstract description 4
- 235000011114 ammonium hydroxide Nutrition 0.000 claims abstract description 4
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 claims description 9
- 229910052791 calcium Inorganic materials 0.000 claims description 4
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- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 claims description 3
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- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims 3
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- 239000012670 alkaline solution Substances 0.000 claims 2
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 claims 1
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- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 claims 1
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- XYJRXVWERLGGKC-UHFFFAOYSA-D pentacalcium;hydroxide;triphosphate Chemical compound [OH-].[Ca+2].[Ca+2].[Ca+2].[Ca+2].[Ca+2].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O XYJRXVWERLGGKC-UHFFFAOYSA-D 0.000 description 2
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Abstract
一种可生物降解磷酸三钙纳米粉体的制造方法，属精细化工领域。其制备方法为：选用廉价易得的硝酸钙Ca(NO3) 2·4H2O和五氧化二磷P2O5为原料，按Ca/P摩尔比为1.5用乙醇溶解，加入适量分散剂，氨水调节pH值为3～11，搅拌均匀，形成稳定的溶胶；将所得溶胶在50～80℃水浴或油浴中陈化1－48小时得到湿凝胶；然后在80－190℃下干燥2－48小时形成干凝胶；将干凝胶研磨成粉末后在800～1250℃之间选择一确定的温度煅烧，分别可制得单分散，纳米级，颗粒均匀，生物活性高的β－磷酸三钙粉体、α－磷酸三钙粉体或二者的复合粉体。
Description
技术领域
本发明涉及一种纳米磷酸三钙粉体的制造方法，属精细化工领域。
背景技术
磷酸三钙生物材料具有良好的生物活性、生物相容性和生物可降解性，已被广泛用于医药和硬组织替代材料，例如，α-磷酸三钙可用来制备骨水泥，多孔的β-磷酸三钙材料已被用于骨感染处抗生素治疗的可控药物缓释载体，β-磷酸三钙牙粘合剂与抗菌剂复合可治疗各类龋齿；Ito等(A.ITO，K.OJIMA，H.NAITO，N.ICHINOSE and T.TATEISHI，J.Biomed.Mater.Res.50(2000)178.)研究发现掺入少量锌的β-磷酸三钙具有很高的细胞活性，而且有利于成骨细胞MC3T3-E1的增殖。目前全世界众多科研机构都在研究用β-磷酸三钙陶瓷作硬组织工程三维支架材料，纯的β-磷酸三钙粉末或β-磷酸三钙与羟基磷灰石的复合粉末制备的三维多孔支架具有降解性，为骨组织的生长提供丰富的Ca和P元素，同时为新生组织的进一步生长提供空间。但目前制备的多孔支架的主要问题在于其初始机械强度不够，只能用于非承重骨的骨组织替换或修复，为使磷酸钙系的生物陶瓷更广泛地用于骨组织修复，必须制备机械强度更高的磷酸钙系生物陶瓷。而要制备机械强度更高的磷酸钙系生物陶瓷的先决条件是要制备比表面积更高、粒径小、粒径分布窄、低团聚的磷酸钙系粉体。宋云京等(无机材料学报，2002，17(5)；985-991)报道了用化学纯的五氧化二磷P2O5和硝酸钙Ca(NO3)2·4H2O为原料，用溶胶凝胶法合成了颗粒均匀，无团聚，纳米级的羟基磷灰石粉体。
中国专利号CN1557774A“磷酸钙系生物陶瓷纳米粉体的制备方法”公开了一种以硝酸钙Ca(NO3)2·4H2O和磷酸三甲酯为原料，合成了包括羟基磷灰石和β-磷酸三钙在内的磷酸钙系生物陶瓷纳米粉体，但所用原料磷酸三甲酯与五氧化二磷相比价格昂贵，且含磷率低。
中国专利号CN1488680A“磷酸钙复合粉末及其制备方法”公开了一种以CaCl2和Na3PO4为原料合成的不同晶相的磷酸钙复合粉体，得到的颗粒两相分布均匀，颗粒尺寸分布均匀，颗粒尺寸在50nm～500nm之间，易于分散。
发明内容
本发明的目的在于提供一种利用廉价原料制备单分散，纳米级，颗粒尺寸分布均匀，生物活性高的磷酸三钙纳米粉体。该方法工艺简单，成本较低，质量稳定。
本发明提供的制备方法是以无机钙盐和五氧化二磷为原料，通过溶胶-凝胶过程，得到晶粒小，团聚少，活性大的磷酸三钙纳米粉体。
现将各有关过程详述如下：
1.无机原料的选择：选用廉价易得的硝酸钙Ca(NO3)2·4H2O和五氧化二磷P2O5为原料，无水乙醇为溶剂。
2.溶胶pH值的选择：pH值过低或过高都会产生沉淀，为得到稳定的溶胶，需控制pH值在3-11之间，伴以搅拌。
3.分散剂的选择：可以选择柠檬酸、聚丙烯酸、聚乙二醇等有机物，也可不加入分散剂。
4.陈化温度及时间：将所得溶胶置于50～80℃的水浴或油浴中陈化1～48小时可得湿凝胶。
5.湿凝胶的干燥可采用非真空干燥或真空干燥，干燥温度为80～180℃，也可采用超临界流体干燥技术。
6.将干凝胶研磨成粉末后在800～1250℃之间选择一确定的温度煅烧，分别可制得单分散，纳米级，颗粒均匀，生物活性高的β-磷酸三钙粉体、α-磷酸三钙粉体或二者的复合粉体。
由上所述，本发明的突出优点为：
1.原料便宜易得，制备工艺简单，工艺参数易于控制，易于大规模工业化生产。
2.本工艺是一种高集成的材料制备技术，制备的磷酸钙纳米粉体可用于生物陶瓷、生物骨水泥及组织工程复合支架材料制备，从而使该工艺具有高度的灵活性和广泛的实用性，彰显产业化的技术风范。
3.本发明所得粉体不经煅烧可直接成型，然后再烧成制备磷酸钙系生物陶瓷。
附图所明：
图一是用本发明制备的粉体经930℃煅烧两小时的XRD谱和标准谱图，从图一可以看到，本发明可制备β-磷酸三钙粉体。
图二是用本发明提供的方法制备的磷酸三钙粉体的透射电镜照片，放大倍数为72000倍。从图二可以看到，本发明制备的粉体分散性好，团聚少，颗粒尺寸分布均匀，颗粒尺寸在50～70nm之间。
具体实施方式
下面通过实例进一步说明本发明的突出特点，仅在于说明本发明而决不限制本发明，亦即，本发明的突出特点和显著进步，决不限于下述实例。
实例1：
按照Ca/P摩尔比为1. 50称取计算量的硝酸钙Ca(NO3)2·4H2O49.4g和五氧化二磷P2O510g，用100ml无水乙醇溶解后，再在上述混合醇溶液中加入分散剂柠檬酸5g；经充分溶解和混合均匀后，用氨水调节pH值为6，再将混合均匀的溶胶在70℃水浴中陈化24小时得到湿凝胶，然后在80℃真空烘箱中干燥24小时得到干凝胶；将干凝胶磨细后，经930℃煅烧2h获得β-磷酸三钙纳米粉体。衍射结果如图一所示。
实例2：
按照Ca/P摩尔比为1.50称取计算量的硝酸钙Ca(NO3)2·4H2O247g和五氧化二磷P2O550g用800ml无水乙醇溶解，经充分溶解和混合均匀后，用氨水调节pH值为6，再将混合均匀的溶胶在70℃水浴中陈化48小时得到湿凝胶，然后在80℃真空烘箱中干燥24小时得到干凝胶；将干凝胶磨细后，经850℃煅烧获得所需的纳米粉体。透射结果如图二所示。
Claims (6)
1，本发明为一种可生物降解磷酸三钙纳米粉体的制备方法，其特征在于；按照Ca/P摩尔比为1.5称取计算量的钙源和磷源用乙醇溶解，再在上述混合醇溶液中加入适量分散剂；经充分溶解和混合均匀后，用碱性溶液调节pH值为3-11，将形成的溶胶在50～80℃水浴或油浴中陈化1-48小时得到凝胶，然后在80-190℃下干燥2-48小时形成干凝胶；将干凝胶磨细后，最后经400-1250℃煅烧获得所需的纳米粉体。
2，按权利要求1所述的可生物降解磷酸三钙纳米粉体的制备方法，其特征在于，通过控制Ca/P摩尔比为1.5，合成可生物降解磷酸三钙纳米粉体，如β-磷酸三钙β-Ca3(PO4)2，Ca/P＝1.50；α-磷酸三钙α-Ca3(PO4)2，Ca/P＝1.50。
3，按权利要求1所述的可生物降解磷酸三钙纳米粉体的制备方法，其特征在于，所说的分散剂为柠檬酸(C6H8O7)，聚乙二醇等有机物。
4，按权利要求1所述的可生物降解磷酸三钙纳米粉体的制备方法，其特征在于，所说的钙源为硝酸钙Ca(NO3)2·4H2O，氯化钙CaCl2或氢氧化钙。
5，按权利要求1所述的可生物降解磷酸三钙纳米粉体的制备方法，其特征在于，所说的磷源为五氧化二磷P2O5。
6，按权利要求1所述的可生物降解磷酸三钙纳米粉体的制备方法，其特征在于，所说的碱性溶液为氨水、氢氧化钠或氢氧化钾。
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105883742A (zh) * | 2016-04-08 | 2016-08-24 | 武汉理工大学 | 一种纳米β-磷酸三钙的制备方法 |
| CN108836441A (zh) * | 2018-04-25 | 2018-11-20 | 郑州大学第附属医院 | 一种介入穿刺装置 |
| CN110092362A (zh) * | 2019-05-08 | 2019-08-06 | 武汉理工大学 | 一种介孔纳米β-磷酸三钙的制备方法 |
| CN111003698A (zh) * | 2019-11-21 | 2020-04-14 | 江阴市星宇化工有限公司 | 一种高活性纳米级磷酸三钙生产反应釜及其使用方法 |
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2005
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105883742A (zh) * | 2016-04-08 | 2016-08-24 | 武汉理工大学 | 一种纳米β-磷酸三钙的制备方法 |
| CN108836441A (zh) * | 2018-04-25 | 2018-11-20 | 郑州大学第附属医院 | 一种介入穿刺装置 |
| CN110092362A (zh) * | 2019-05-08 | 2019-08-06 | 武汉理工大学 | 一种介孔纳米β-磷酸三钙的制备方法 |
| CN111003698A (zh) * | 2019-11-21 | 2020-04-14 | 江阴市星宇化工有限公司 | 一种高活性纳米级磷酸三钙生产反应釜及其使用方法 |
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