FLVP assays
Perform preparation of FLVPs as described in Viral and bacterial isolates , propagation and preparation of stocks .
Prepare a 10 - fold dilution series of the culture or natural sample to be enumerated so that ~ 105 cells mL–1 of the target ( FLVP - specific species ) will be obtained .
Perform all subsequent steps under subdued light , since the stain will fade if exposed .
Add 0.1 mL FLVP working stock to 0.9 mL sample in a microcentrifuge tube for each slide to be prepared and vortex to mix .
Allow up to 30 min for adsorption of FLVPs to target cells .
Filter each 1 mL sample onto a 0.2 - µm Anodisc filter using a 0.45 - µm HA filter for backing .
Pipette 10 µL mounting medium onto the surface of a slide .
Place the filter over the drop .
Pipette 10 µL mounting medium onto the surface of the filter .
Place a 25 × 25 mm coverslip over the filter .
Observe the slides under blue - light excitation and count the cells with a fluorescent halo .
