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bioRxiv · 10.1101/386060

Two-step concentration of complex water samples for the detection of viruses

Farkas, K.·McDonald, J. E.·Malham, S. K.·Jones, D. L.
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Abstract

The accurate detection and quantification of pathogenic viruses in water is essential to understand and reduce the risk of human infection. In this paper, we validated a two-step method for the concentration of enteric viruses in water and wastewater samples. The method involves a tangential flow ultrafiltration step that reduces the sample volume of 1 - 10 L to approx. 50 mL, followed by secondary precipitation using polyethylene glycol 6000 that reduces the volume to 1 - 4 mL. For method validation, surface water samples were spiked with different concentrations of enteric viruses and viral recoveries in the concentrates exceeded 10% in all experiments. The method is suitable for water samples with high and low salinity and turbidity, allowing the accurate comparison of viral titers in a diverse range of water types. Furthermore, the method has the potential to concentrate other pathogens, e.g. bacteria or protozoa. Hence, the use of this method can improve the holistic assessment of risks associated with wastewater contaminated environments.\n\nO_LIModified tangential flow ultrafiltration method that reduces membrane clogging.\nC_LIO_LISecondary concentration with a beef extract-elution step to remove solid matter.\nC_LIO_LIThe two-step concentration method enables at least 10% recovery for different enteric viruses in difficult matrices.\nC_LIO_LIUsing the two-step concentration method 10,000x concentration can be achieved.\nC_LI\n\nSpecifications Table:\n\n\n\nO_TBL View this table:\norg.highwire.dtl.DTLVardef@12d4fceorg.highwire.dtl.DTLVardef@1d2880borg.highwire.dtl.DTLVardef@e1acf6org.highwire.dtl.DTLVardef@226492org.highwire.dtl.DTLVardef@1f8edf0_HPS_FORMAT_FIGEXP M_TBL C_TBL

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Farkas, K., McDonald, J. E., Malham, S. K., Jones, D. L.. 2018-08-07. Two-step concentration of complex water samples for the detection of viruses. https://doi.org/10.1101/386060

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