Deposition of Cryptosporidium parvum oocysts on natural organic matter surfaces: microscopic evidence for secondary minimum deposition in a radial stagnation point flow cell.
A radial stagnation point flow (RSPF) system combined with a microscope was used to determine the deposition kinetics of Cryptosporidium parvum oocysts on quartz surfaces and silica surfaces coated with Suwannee River natural organic matter (SRNOM) in solutions with different ionic strengths. Microscopic evidence of C. parvum oocysts entrapped in the secondary minimum energy well was presented to show that among the entrapped C. parvum oocysts some were washed away by the radial flow and some were able to transfer to deep primary minima and become irreversibly deposited. Experimental data were compared with simulation results obtained by the convective-diffusion equation and Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. The experimental results suggested that surface charge heterogeneity led to a higher attachment efficiency at low ionic strength. In addition, the maximum attachment efficiency was less than 1 at high ionic strength due to steric interaction.
Liu
Yuanyuan
Y
Department of Civil and Environmental Engineering, The Center of Advanced Materials for the Purification of Water with System and Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
Janjaroen
Dao
D
Kuhlenschmidt
Mark S
MS
Kuhlenschmidt
Theresa B
TB
Nguyen
Thanh H
TH
D000818:Animals; D001688:Biological Products / Q000737:chemistry*; D048430:Cell Shape; D016785:Cryptosporidium parvum / Q000737:chemistry* / Q000166:cytology*; D005260:Female; D007700:Kinetics; D033661:Oocysts / Q000737:chemistry* / Q000166:cytology*; D009930:Organic Chemicals / Q000737:chemistry*; D013499:Surface Properties
D001688:Biological Products; D009930:Organic Chemicals