R&R Ultra-Competent Cells Transformation Kit™

US$59.00
Number of reactions
About the Ultra-Competent Cells Transformation Kit™

The R&R Kit is designed for researchers that want a low-cost, on-demand,  rapid, long-shelf-life, and robust transformation tool that is stable in the fridge. It's time to spend less and get more!

  • Cost: Traditional ultra-competent cells that you store in the -80 C freezer cost about $13 per transformation reaction. The R&R Kit costs less than half per reaction:  10 rxns kit costs US$6 per reaction, 20 rxns kit costs  US$5.50 per reaction, 30 rxns kit costs  US$5 per reaction
  • On-demand: R&R Kit is stored in the fridge for extended periods of time and can be used at any time. There is no extensive preparation of buffers, measuring pH, or scouring the department for metal salts. Just grab the kit from the fridge and use the contents inside to do the transformation.
  • Rapid: The R&R Kit requires 2.5 hours of total time to transform cells, including a 2 hour incubation period where you can go for lunch, actually write your thesis, or set up and run a quick ligation. Actual bench time with the R&R Kit is less than 30 minutes.
  • Long shelf-life: The R&R Kit lasts in a fridge for at least 9 months. Traditional ultra-competent cells that you make in-house or buy commercially have an optimal shelf life of days, and if your cells are stored at a temperature above -70 C for even a short period of time the competency drops substantially (does your lab mate leave the -80 door open for extended periods of time?).
  • Robust: The transformation efficiency of the R&R Kit is comparable to or even better than traditional ultra-competent cells. For clean plasmid preps, it works phenomenally. For ligation reactions, you’ll typically get several colonies (so long as your ligation was successful!).

Type of DNA

Expected result (20 min recovery)

Expected result (overnight recovery)

Mini-prepped plasmid DNA (1-10 ng/uL)

100+ CFU

250 CFU to lawn

Ligation mix (~10 ng/uL)*

Up to 50 CFU

up to 100 CFU

PCR cleanup Ligation mix (1-10 ng/uL)*

10+ CFU

25+ CFU

*Transformation efficiency is primarily dependent on the restriction sites used, the quality of pre-ligation DNA parts, and the success of the ligation reaction.

Common Lab problems (its not you, its the competent cells!)


• Have you tried to transform cells many times with not success? There is a possibility that your ligation worked great, but those expensive cells have lost their competency because they are very temperature sensitive!

• Have you tried to make your own ultra competent cells and they kinda work? The time commitment to find a recipe, make your own cells, and store your own cells is huge. An entire day can be spent spooling up a batch of competent cells and the performance may not be there.

• Ordering expensive cells again! Ordering expensive cells cause friction with your PI. Explain to them you found an option that cost less than half the price and have a longer shelf life than the expensive ones - you may get the thumbs up!

• Want to try transforming in a different strain? If you have other E. coli strains on hand in petri dishes or glycerol stocks, you can easily make them ultra competent and run a transformation with them using the R&R Kit. You have flexibility, you’re not tied to the one type of cells.

What's included?

This kit includes:
• Ready-to-use, single-use R&R Elevate Buffer
• Master tube of Transformation Buffer
• Ready-to-use, single-use Recovery Media
• Inoculation loops
• Multi-use* DH5alpha E. coli stabs

*opening of stabs should be done in a laminar flow hood or biosafety cabinet. If you do not have one, then the stabs should be considered single-use
Need help? Reach out!

What else is needed?

• centrifuge (10,000 x g)
• crushed ice*
• 42 C block/water bath*
• 37 C incubator*

*These three items and the associated mess can be eliminated with the help of a DNA Playground

Storage & Shipping

This kit(s) must be refrigerated upon arrival for best shelf life. If your experiment kits stay at room temperature before you collect it from your mailbox/mailroom/etc, that's ok! As long as kits do not freeze, and they are stored in a refrigerator if you are not using it right away, there's no need to worry. If you do not have access to a refrigerator to store your kit, use it within 3 weeks.