Incubators - Direct heat vs water jacketed (Mar/23/2007 )
Hi everybody!
Is there a good reason not to buy a direct heat incubator over a water jacketed one? The main argument seems to be the capacity of the latter to keep temperature longer than the other in case of electrical failure. But I wonder if someone could give me other reasons. Direct heat incubators cost a little bit less than the WJ's.
Thanks a lot!
The water jacket not only protects in case of power failure, but also maintains a more consistent temperature than an open-convection incubator. For example, when you open the door to get your culture, the ambient temp inside either drops 3-4 degrees. A water-jacketed incubator however re-equilibrates more quickly(~10 min), and does not over correct like a convection incubator is prone to. On the non-technical side, a Water jacket is HEAVY (even without the water), so if you ever expect to have to move it around, that may be a consideration too.
That said, I think it depends most importantly on the temperature sensitivity/resiliency the cells you're growing. If mammalian cells, I would highly advocate a water jacket model if the $$$ is available. Other taxa - prokaryotes, fungi, insect, plant, etc - may be more resilient to such fluctuation. For example my E.coli grow just fine in a very old convection incubator even though it takes quite a while (~1-2hr, depending on how long the door is open) to return to set temp, and usually goes slightly above the set temp before equilibrating. Good Luck Shopping
(P.S. You can find a lot of lightly used but perfectly functional equipment on E-bay, super cheap. I just bought a practically new lypohilizer for only $200US. I saw some incuators there too!).
Hi JAH, I appretiate your helpful insight. Since I am going to grow mammalian cells I will follow your advice. I also appretiate your info about E-bay, unfortunately I am not in the USA, therefore I wont be able to take advantage of such bargains.
Read you around
semcells
That said, I think it depends most importantly on the temperature sensitivity/resiliency the cells you're growing. If mammalian cells, I would highly advocate a water jacket model if the $$$ is available. Other taxa - prokaryotes, fungi, insect, plant, etc - may be more resilient to such fluctuation. For example my E.coli grow just fine in a very old convection incubator even though it takes quite a while (~1-2hr, depending on how long the door is open) to return to set temp, and usually goes slightly above the set temp before equilibrating. Good Luck Shopping
(P.S. You can find a lot of lightly used but perfectly functional equipment on E-bay, super cheap. I just bought a practically new lypohilizer for only $200US. I saw some incuators there too!).
Read you around
semcells
That said, I think it depends most importantly on the temperature sensitivity/resiliency the cells you're growing. If mammalian cells, I would highly advocate a water jacket model if the $$$ is available. Other taxa - prokaryotes, fungi, insect, plant, etc - may be more resilient to such fluctuation. For example my E.coli grow just fine in a very old convection incubator even though it takes quite a while (~1-2hr, depending on how long the door is open) to return to set temp, and usually goes slightly above the set temp before equilibrating. Good Luck Shopping
(P.S. You can find a lot of lightly used but perfectly functional equipment on E-bay, super cheap. I just bought a practically new lypohilizer for only $200US. I saw some incuators there too!).
Dear Semcells,
Water Jacketed incubators are a beast from the past. We used to use these years ago to help with high ambient temperatures that affected the running of 37oC incubators. If you have good air conditioning/controlled temperatures DO NOT BUY THEM. As JAH said these beast are really heavy and are difficult to manual handle. Again JAH is right when commenting on water jacketing reducing the drop in temperature when opening the door.
Question: Does this drop really matter.............i.e. when trypsinising cells in the class II cabinet, what is the drop in temperature the cells go through? and for how long ? Ambient temperature in our place is 21oC.
The PBS, Media and Trypsin are all warmed in the waterbath prior to subculture.....what is their drop in temperature.
Dear Rhombus, very interesting your point! As a matter of fact, for WJ incubators, aside from the weight issue, I worry the most about water level unexpectedly dropping.
Regarding DH incubators, I want to believe that today's incubators control temperature very tightly, since I would be more concerned about raises of temp rather than droppings.
Thanks for your comments!
Semcells
Dear Semcells,
Water Jacketed incubators are a beast from the past. We used to use these years ago to help with high ambient temperatures that affected the running of 37oC incubators. If you have good air conditioning/controlled temperatures DO NOT BUY THEM. As JAH said these beast are really heavy and are difficult to manual handle. Again JAH is right when commenting on water jacketing reducing the drop in temperature when opening the door.
Question: Does this drop really matter.............i.e. when trypsinising cells in the class II cabinet, what is the drop in temperature the cells go through? and for how long ? Ambient temperature in our place is 21oC.
The PBS, Media and Trypsin are all warmed in the waterbath prior to subculture.....what is their drop in temperature.
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