纳米羟基磷灰石的表面改性及其细胞毒性的研究

Surface Modification of Nano-Hydroxyapatites and Their Cell Cytotoxicity

利用聚乙烯亚胺(PEI)和聚丙烯酸钠(PAA)对纳米羟基磷灰石(nHA)进行表面改性,并从影响细胞增殖和凋亡的角度出发,采用四唑盐比色法(MTT法)和荧光染色法对改性后的纳米羟基磷灰石颗粒进行了体外细胞毒性评价。结果表明:利用PEI和PAA可以显著地改变nHA的表面电性;而细胞的毒性与其共培养的颗粒表面电性、浓度和共培养时间有关,在较低浓度下,没有经过表面改性的纳米羟基磷灰石颗粒具有最好的细胞相容性,其细胞毒性为0级,PEI改性的纳米颗粒的细胞相容性最差,而PAA改性的纳米颗粒的细胞相容性介于二者之间。初步证明了表面电性对材料细胞毒性的影响,即正电性纳米颗粒的细胞毒性较大。

Nano-hydroxyapatite（nHA） is modified using PEI and PAA.The cell cytotoxicity of modified nHA is evaluated from a view-point of cell proliferation by MTT and fluorescence method.The result shows that the zeta potential of nHA particles can be changed remarkably with the surface modification by PEI and PAA.The cytotoxicity of nHA particles is related to the zeta potential,particle concentration in the cell culture medium and culture time.The nHA particles with almost neutral and negative potentials have good cell biocompatibility at a low particle concentration and long culture time,which probably can be used as a replacer of bone and carrier of DNA and drug.