Experimental Protocols

Protocols I use in my research, shared in the spirit of open science. They are living documents and get updated as I learn more. Questions or suggestions? Email me.

Phage fluorescent labeling

Pass filtered phage lysate (phages removed from bacteria ater growth) once through 100 kDa amicon filter (in a benchtop centrifuge, not ultracentrifuge) to exchange media to PBS (pH 7.4). This helps get rid of molecules … (click to expand)

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Pass filtered phage lysate (phages removed from bacteria ater growth) once through 100 kDa amicon filter (in a benchtop centrifuge, not ultracentrifuge) to exchange media to PBS (pH 7.4). This helps get rid of molecules in the lysate that the dye might bind to. See below my protocol: 

Dye prep (only done when receiving new dye, not each time labeling occurs):
- Fresh 1 mg AZdye TFP ester 488 (or 568 or ... you can choose your own based on your filter set) is dissolved into 200 uL water.
- 10 uL aliquots are made into centrifuge tubes.
- dye is desiccated by running these samples through a speedvac, and the tubes are stored at -20 C in airtight container with desiccant until further use.

Labeling:
- a dye aliquot is taken out of the freezer and incubated at room temperature in airtight container (e.g., a 50 mL centrifuge tube) with desiccant.
- phage lysate (100-500 uL) is dissolved in PBS to a final volume of 4 mL filtered using 100 kDa Amicon filters and resuspended in 100 uL PBS.
- 100 uL of the phage lysate is transferred to the tube with dye aliquot and pipette-mixed.
- the tube is incubated with gentle shaking at room temperature for 2-3 hours. optional: overnight incubation at 4 C. Excess dye is washed (through amicon filters) 4X with PBS.

Phage growth (for beginners)

This protocol is written for folks who are starting out phage work and don’t super care about getting the maximum yield (highest titer or concentration of phages). Once you carry out literature review, you might find …

Last updated on Oct 1, 2026