Published: March 29th, 2019 Last Modified: April 21st, 2019
Make a lot of media? Don’t want to drag out your 2 kilo jars of tryptone, yeast extract and salt every time? Make some pre-mix quickly, cheaply and easily!
Also, learn the dark art of microwaving agar plates. Just a trick to keep in the back of your pocket for when things don’t go according to plan.
Using mini-blenders like the magic bullet is very convenient as it allows you to make up to 10-20 liters worth of powdered media ahead of time. Nothing much to add on top of the video. It’s an easy upgrade to your lab and should cost you less than 70$ for the initial setup.
If you’d like to directly support me and the blog, you can purchase the blender and accessories you see from Amazon with the links below. You don’t pay an extra cent and I get a small cut from Amazon, win win!
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Nice, but I missed the point of pre-blending… I made thousands of LB and LB-Agar from the components in my PhD days and never bothered to pre-mix. As everything (beside the agar) is water-soluble you can simply weigh all components (beside agar), add water, and mix. If no magnetic stirrer stir, don’t shake.
In an ideal world with unlimited funding you would buy pre-made mixes from commercial suppliers and save time (and mess) weighing individual ingredients. Do you save THAT much time with a pre-made mix? Eh…I think it depends on scale and frequency, and for most labs it’s a luxury to buy pre-made mixes. With the mini-blender method you can get a taste of that luxury, input some of your time making the pre-mix and reap it later, especially for more complex medias. I’ve been making my own pre-mixes for a while now and I do appreciate it’s increased efficiency. However I would not argue that assembling LB media from scratch is as wholesome of a lab activity as you can get, just like my daddy before me and his daddy before him.
I make my ampicillin/kanamycin agar using the microwave method all the time. There is no real problem when you just use the plates for routine E.coli maintenance and quick cloning/subcloning procedures.
FYI, you can even do this with liquid broths, just microwave it till it boils a little. I guess since we are adding antibiotics anyway, contamination concerns are minimized. Better than the historical Pasteur swan neck experiment, which did not get contaminated for a long period of time.