硅氧聚合度对细胞毒性的影响

EFFECT OF DEGREE OF POLYMERIZATION OF SILICA ON ITS CYTOTOXICITY

本文采用家兔肺泡巨噬细胞(AM)存活率和细胞过氧化脂质(LPO)值为测定指标,研究了硅氧的聚合度对其细胞毒性的影响。结果表明:各种聚合度的硅氧都有一定的细胞毒性,聚合度愈大,细胞毒性也愈大。胶体SiO_2的粒径增大,其细胞毒性降低。十硅酸盐及粒径小于5nm的硅溶胶的细胞毒性大于α-石英。聚合度小于6的低聚硅酸及其盐、粒径18nm以上的硅溶胶以及硅胶H的毒性皆小于α-石英。本实验细胞存活率降低和过氧化脂质值升高的趋势基本一致,这表明硅氧可能主要与细胞表面膜作用,膜上磷脂等表面活性物质被氧化和变性,从而导致细胞损伤。

In this paper, the survival percents and lipid peroxide(LPO) values of alveolar macrophage(AM) in rabbit lung after incubation with some sorts of silica(polysilicic acids, synthesized polysilicates, silica gel and a-quartz) are determined. The relationship between degree of polymerization(D.P.) of silica and its toxic effect on AM has been studied. The results show that every kind of silica with different D.P. is toxic on AM. The higher the D.P., the stronger the toxicity; and the larger the particle size of silica sol, the weaker the toxic effect. Decasilicate and silica sols with particle size less than 5 nm are more toxic than a-quartz. Oligosilicates(D.P.<6), silica sols(particle size>18nm) and silica gel are all less toxic than a-quartz. The reduction of survival percents of AM is corresponding to the increase of its LPO value. It is showed that silica mainly reacts with the surface of cell membrane, and the surfactant of membrane such as phospholipid will be oxidized and denatured, resulting in cell damaging.