Real-time microgravimetric quantification of Cryptosporidium parvum in the presence of potential interferents.
The quartz crystal microbalance with dissipation monitoring (QCM-D) is used to develop a biosensor for detection of viable Cryptosporidium parvum (C. parvum) in water matrices of varying complexity. In a clean environment, a good log-log linear response is obtained for detection of C. parvum in aqueous suspensions with oocyst concentrations from 3x10(5) to 1x10(7)oocysts/mL. C. parvum detection is slightly affected by the presence of dissolved organic acids, likely due to steric stabilization and/or masking of the antibodies/antigens by adsorbed molecules. Colloidal contaminants generally have a greater influence as biosensor interferents, whereby the presence of model latex microspheres, Enterococcus faecalis, or Escherichia coli, led to decreases in biosensor response of up to 64%, 40%, and 20%, respectively.
Department of Chemical Engineering, McGill University, Montreal, Quebec, Canada H3A 2B2.
Charles
C
Poitras
Julien
J
Fatisson
Nathalie
N
Tufenkji
D000818:Animals; D015374:Biosensing Techniques; D016785:Cryptosporidium parvum / Q000302:isolation & purification* / Q000648:ultrastructure; D013293:Enterococcus faecalis; D004926:Escherichia coli; D055617:Micro-Electrical-Mechanical Systems / Q000379:methods*; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D033661:Oocysts / Q000648:ultrastructure