Sorption of Cryptosporidium parvum Oocysts in Aqueous Solution to Metal Oxide and Hydrophobic Substrates
The parasite Cryptosporidium parvum (C. parvum) may be introduced into water supplies by a number of processes, including runoff and infiltration from areas where wastes from infected hosts are dispersed on soils. Soil particles may attenuate or, when suspended in flow with sufficient kinetic energy, act as transport sites for oocysts. Sorption may also be reversed by the frictional force of flowing water. As a first step toward understanding oocyst attentuation and transport, we examined partitioning in a two-phase, laminar flow microduct. This exposed aqueous suspensions of C. parvum oocysts to metal oxide and hydrophobic substrates (Al2O3, Fe2O3, SiO2, and octadecyltrichlorosilane ((OTS) CH3(CH2)17SiCl3, a hydrophobic monolayer)) on transparent glass slides. Sorption under laminar flow conditions was observed for unexposed oocysts and oocysts subjected to freeze−thaw cycling and desiccation. The results indicate differences in sorption between substrates and oocyst exposure to stresses. Regardless of e...