The effect of aluminium citrate on electrokinetic potential on the surface of quartz and titanium dioxide particles.
Cao-CJ; Liu-SJ; Lin-KC
NIOSH 1990 Sep; :742-746
A study was made of the aluminum content, charge density and electrokinetic potential on the surface of quartz (14808607) and titanium-dioxide (13463677) particles and of the effects of aluminum- citrate (AlC) and aluminum-chloride (AlCl3) on such properties. Quartz particle diameter was less than 5 microns, most particles being less than 2 microns. The specific surface was 4.59 square meters per gram. Titanium-dioxide particles had similar dimensions. Suspensions of 1mg/ml were made in deionized water. Analyses included fluorescence spectrometry, viscosimetry and microelectrophoresis. Little inherent aluminum was detected on either particle type. Surface bound aluminum increased with increasing added aluminum to some extent for quartz particles, while there was no detectable binding of aluminum to titanium-dioxide particles. Similar amounts of aluminum bound to quartz pretreated with AlC or AlCl3. Both particle types had negatively charged surfaces, but the charge density was significantly higher for quartz particles. Surface electrophoretic potential of quartz was 34.5% higher than that of titanium-dioxide. Treatment of quartz particles with AlC or AlCl3 decreased electrophoretic mobility and surface electrokinetic potential; this was not noted with treated titanium- dioxide particles. The authors conclude that these data provide further evidence for the mechanisms of quartz induced membrane damage and its antagonism by AlC, and they suggest the use of aluminum as a preventive measure for silicosis in the workplace.
Mineral-dusts; In-vitro-studies; Quartz-dust; Metallic-dusts; Surface-properties; Dust-particles; Electrical-properties; Drug-interaction; Aluminum-compounds
DHHS (NIOSH) Publication No. 90-108
Proceedings of the VIIth International Pneumoconioses Conference