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Clonidine by electrochemical detection?

Posted: Mon Jan 24, 2005 3:20 pm
by Ann
Dear All

Has anybody successfully quantified clonidine using electrochemical detection? The compound is electrically active (according to the ESA website) but I can't find any further info on the optimum conditions (after a general web search and PubMed). Grateful for any info or opinions (while I attempt to work it out myself in the lab!)

With thanks and best wishes

Ann

Posted: Mon Jan 24, 2005 7:25 pm
by Steve
Ann

Macherey-Nagel has been in the chromatography business for over 90 years. We have an extensive database of over 2300 products. Enclosed is the web address were the determination of clonidine hydrochloride in pharmaceutical preparations by HPLC can be found.

https://www.macherey-nagel.com/web/MN-W ... =HPLC00952

Hopes this helps you out.

Posted: Mon Jan 24, 2005 10:51 pm
by Ann
Hi Steve

Many thanks for your post, much appreciated. However, I do already have an assay for clonidine using UV detection. Unfortunately, it seems unlikely that I will achieve the required assay sensitivity using UV, hence my interest in electrochemical detection.

Best wishes

Ann

Posted: Tue Jan 25, 2005 3:49 am
by AA
Near as I can tell, any method that would work for catecholamines should work for this compound. After having said that, there is little doubt that you would need to optimize the separation and the ECD conditions. I did find this paper (although they do not show a chromatogram), http://www.druglibrary.org/crl/behavior/jentsch-01.pdf

Posted: Tue Jan 25, 2005 10:19 pm
by Ann
Hi AA

Thank you for your reply and for taking the time to post the link for that manuscript, much appreciated. However, having read the paper I think that the authors were quantifying dopamine concentrations produced in the presence (or absence) of clonidine, rather than quantifying clonidine itself.

All the best

Ann

Posted: Sun Feb 06, 2005 3:22 pm
by Ann
Hello all

An update on the clonidine electrochemical detection situation. After failing to detect the compound in either oxidation or reduction mode, I contacted ESA for further info and it seems that they cannot trace any information on clonidine and cannot explain why it is listed as an electroactive compound on their website. They will be removing it from their list. So it seems I have to go with UV after all!

Ann

Posted: Mon Feb 07, 2005 4:27 pm
by AA
I do have a reference that states it can be done on Glassy Carbon at 1.2V.

J. Chrom. 323 191 1985

Posted: Tue Feb 08, 2005 9:48 am
by Ann
Hi AA

Thanks for this, I'm very interested (have previously only tried up to +/- 1V). Any chance you could give me further details (authors etc) on that reference as I can't find it using the usual sources (PubMed etc)?

With thanks and best wishes

Ann