Particle size and chemically-induced variability in the membrolytic activity of quartz: preliminary observations.
Nolan-RP; Langer-AM; Foster-KW
In Vitro Effects of Mineral Dusts. Third International Workshop. Beck EG, Bignon J, eds., New York: Springer-Verlag, 1985 Jan; :39-50
Quartz (14808607) surface was modified by reproducible techniques, such as acid, base, and heat treatment, and the effect on the membrolytic activity was studied. Chemically modified quartz was sized by light microscopy. Quartz particles were irregular in shape, and both particle shape and size distribution were approximated. As a useful quantitative assay, lysis of a standard suspension of washed human erythrocytes, at a final concentration of 1.8 x 10(8) cells/milliliter, was studied after incubation with various concentrations of quartz at 37 degrees-C for 120 minutes. Membrolytic activity of surface modified quartz was studied after potassium-hydroxide modification, hydrofluoric-acid modification, and dimethylchlorosilane modification. Binding of poly(2- vinylpyridine-N-oxide) (PVPO) to surface modified quartz was studied to assess physicochemical characteristics. The range of membrolytic activities of single quartz specimens depended on the particle size distribution and surface properties. Surface modification by different treatments altered the hemolytic index markedly. PVPO studies suggested that an increased hydrogen bonding ability may actually reduce activity.
NIOSH-Grant; Quartz-dust; In-vitro-studies; Membrane-dysfunction; Particulates; Microscopic-analysis; Acids; Heat-treatment; Red-blood-cells; Mineral-dusts; Humans
In Vitro Effects of Mineral Dusts. Third International Workshop
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