CLND... any thoughts?

[Rob Burgess]

Has anyone out there used the chemiluminescent nitrogen specific HPLC detector in anger. I'd be interested to hear any thoughts / experiences about it whatsoever, be it good or bad.

Further, I'd be partcularly interested in hearing from other users who are using the CLND to calculate relative response factors (or correction factors) in impurity analyses. Has it been successful?

[Yury Zelechonok]

My experience is negative. We use this detector occasionally, but every time I need it, it was out of order and requires technician and few parts to be replaced. This may mean that we did not follow storage procedure which in a manual some where, but who RTFM.
Response factor is a problem too. We had a series of compounds with way low response factor that it suppose to be if compare with non related standard. In the end you can not use MeCN and ammonia buffers as the mobile phase which limits you choices in method development.

[Kostas Petritis]

Rob,

My experience is relatively good. I worked with this detector for about 6 months. My suggestions would be to use a dedicated HPLC system that has never seen nitrogen containing solvents or additives before (for maximum sensitivity). There are also some limitations at the flow rates that you can use. Also, my experience in terms of response factors is quite good. There are some well documented cases where the response is not equimolar (for certain chemical structures).

You may look at: K. Petritis et al. LC-GC Europe 14 (2001) 389-395

It is my understanding that this detector has been improved lately (the last 5 years) but it used to be quite tricky to use. When I worked with it, I noticed that the detector can further be improved (i.e. spray, pyrolysis tube, etc...).

Anyway, I would recommend that detector. Not as easy to use as a UV but much easier to use than a MS.