Chromatography Forum

Our Agilent LC/MS Iontrap has problem of needle blockage. It can accept flows below 0.2ml/min. The CE told us it's because of a blockage in the needle. He just want us to replace it. I do not know if somehow we can unblock it. Any ideas are highly appreciated.
Thanks.

I'm not sure if it works with your Agilent. We have a Shimadzu LCMS, where the ESI-needle tends to clog. I connect it in reverse direction to a pump and flush it with something like IPA/ACN.
The construction of the Shimadzu-ESI is such, that the neddle is inside a small tube, to which standard SS-fittings are attached. So its easy to connect it to a pump.


I have never done something like this to our Agilent though, since it never clogged.

Thanks Thomas,
We have made it unclogged. We just put it in a beaker full of MeOH and put in a ultrasonic bath for ~10 minutes. It works.