Effects of Bacteriophage on the Surface Properties of Chalcopyrite (CuFeS2), and Phage-Induced Flocculation of Chalcopyrite, Glacial Till, and Oil Sands Tailings

The binding of mineral-specific phage to the surface of chalcopyrite (CuFeS2) was investigated by using X-ray photoelectron spectroscopy and scanning Auger microscopy. These studies confirmed the elemental composition of the minerals and confirmed that bacteriophage were bound to the mineral surface. These techniques also revealed that the phage were not forming a continuous film over the entire surface of the CuFeS2 particles, but selectively bound to the slimes coating the particles. In addition, the effect of mineral-specific phage binding to the surface of CuFeS2 was investigated using induction time and zeta potential measurements. Bacteriophage (10(12)/mL) increased the induction time (contact time resulting in 50% particle attachment to a bubble) from similar to 7.5 to similar to 17 ms and reversed the zeta potential from negative to positive. In the course of performing the zeta potential measurements on particles < 45 mu m in diameter, phage-induced aggregation was observed. The mechanism of aggregation was explored using a range of pH (3-11) and cation concentrations. Aggregation was observed across the tested pH range and with all cations. Phage also mediated aggregation of glacial till and oil sands tailings in a dose-dependent and particle size-dependent manner. We conclude that binding of bacteriophage to the surface of CuFeS2 does alter its surface properties. Biotechnol. Bioeng. 2011; 108: 1579-1590. (C) 2011 Wiley Periodicals, Inc.