WPI or Femtojet for Viral Injections?


Anyone have any preferences on injectors for viral injections into the spinal cord and brain? I used the popular WPI UMP4 micropump this summer. It worked, but it requires one to fill a Hamilton syringe and glass pipette with mineral oil all the way through in order to maintain pressure throughout the whole setup.

I’ve seen some papers using a pressure injection system, namely the Femtojet (Eppendorf). This looks attractive because it doesn’t require the filling of oil or other liquid. But I don’t see it used as much. Anyone have any experience?

http://www.ncbi.nlm.nih.gov/pubmed/26387932 (femtojet)

@cedric.peirs @RPSeal @SamineniV @liz


We use the WPI UMP3 in our lab, which I’m assuming is just an older version of the UMP4, with a Hamilton syringe. Instead of using the glass pipette + Hamilton syringe combo, we simply use a small-volume (2.5ul) Hamilton syringe with a removable 28 or 33 gauge needle (also from Hamilton). I’m not sure the removable needle would work in the spinal cord, since 33 ga might still be too large, and you may want the precise tip shape that you would be able to achieve by pulling your own glass pipettes. But for brain injections we routinely use the removable needle with injection volumes of 100-1000nl.


Thanks @liz. Yes for the brain, I’d just use one of those removable needles that come with the Hamilton syringe. But I think they are too big for the cord. I see brain people use those all the time and they don’t mess with the glass pipettes.