Surface and bulk infrared modes of crystalline and amorphous silica particles: a study of the relation of surface structure to cytotoxicity of respirable silica.
Pandurangi RS; Seehra MS; Razzaboni BL; Bolsaitis P
Environ Health Perspectives 1990 Jun; 86:327-336
Surface ir (infrared) modes of crystalline and fumed (amorphous) silica particles, calcined at temperatures up to 1,095 deg. C, have been studied by fourier transform infrared spectroscopy. The ability of these same particles to lyse cells has been measured by a hemolysis protocol. The untreated cystalline and amorphous materials differ by a factor of 40 in specific surface area, and the intensity per unit mass of the sharp surface silanol band near 3,745 cm-1 in the amorphous material is an order of magnitude larger than in the crystalline material. A similar difference is observed in the lysing potential of the two materials. The intensity of the silanol band increases after calcination for both materials, reaching peak values near 500 deg. C, followed by a dramatic drop at higher calcination temperatures, and reaching negligible values for materials calcined near 1,100 deg. C. The lysing potential data follow essentially the same pattern for both crystalline and fumed silica. These results are consistent with the hypothesis that the surface silanol groups are involved in cell lysis. Further experiments are suggested to evaluate the relationship between the surface structure of silica particles and their potential cytotoxicity.
Silica-dusts; Infrared-spectroscopy; Spectrographic-analysis; Hemolysis; Dust-analysis; Dust-particles; Particulate-dust; Airborne-particles; Respirable-dust
IH; Final Contract Report; Journal Article
Environmental Health Perspectives
West Virginia University