Small animal induction chambers are necessary for safe inhalation anesthesia delivery. Current commercial chambers are expensive and unnecessarily leaky, exposing researchers and veterinarians to dangerous gasses. Here is a simple design that can easily be fabricated from off the shelf components. It can be directly incorporated into current gas anesthesia nose cone stereotaxic frame systems typically used for viral injections, electrophysiology recordings, etc.
Food storage boxes create excellent seals and can be clear. The Omnia Food Storage Boxes is a excellent quality, and the 2000 ml. 10074980 is an appropriate size for a gerbil with sufficiently high walls. The seal is great, and the top is quite easy to drill through.
Fit all tubing to the size of your existing anesthesia system. The parts used here are examples for the system with which we were working. All barbed connections should make good, repeatable seals, but you may wish to secure with zip ties.
Drill two holes in the top of the container sufficiently large enough to insert two Barbed Panel Mounts (example: McMaster 5463K84). Insert an O Ring (example: McMaster 9452K24) over the threading of the Barbed Panel Mount. Place this into the top of the container such that the barb will face up. Place another O Ring over the threading and secure the assembly with the given screw. Repeat for the second hole. Connect your tubing. Good tubing should be resistant to chemicals (example: McMaster 5155T39).
You can direct the airflow through either the chamber or a nose cone system with a 3-way stopcock. Well, actually, 2 stopcocks (one for the inlet and one for the outlet). Cole-Parmer 3060002 Stopcocks with Luer Connections are excellent quality, but use a connector type called Luer Lock. In order to connect this to our barbed tubing system, you will need two McMaster 51525K276 and one McMaster 51525K286.
For these stopcocks, the inlet is the female side and the air will flow in the direction of the arrow.
(!) Make sure to always have the two stopcocks in agreement. That is, if the inlet leads to the induction chamber, the outlet should come from the induction chamber. (!)
(!) Clean only with soap and water: no alcohols that will harm the plastic. Note that Melamine Sponges (generic Magic Eraser) are cheap and SUPER handy. (!)
ONE Core acknowledgement
Please acknowledge the ONE Core facility in your publications. An appropriate wording would be:
“The Optogenetics and Neural Engineering (ONE) Core at the University of Colorado School of Medicine provided engineering support for this research. The ONE Core is part of the NeuroTechnology Center, funded in part by the School of Medicine and by the National Institute of Neurological Disorders and Stroke of the National Institutes of Health under award number P30NS048154.”