We are setting up clinical lab. in a large hospital. The lab has an isocratic HPLC system with an electrochemical detector and UV.

We are already doing regular analyses of plasma catecholamines using the ECD.

We are very keen to extend our repertoire into our other clinical analyses. We'd welcome any suggestions from clinical chromatographers.

Thanks.

If you can get hold of them you may want to try HPLC kits from Bio-Rad, Waters, Chromsystems, Recipe, Biometra, Merck.(Darmstadt). There are others, but the market changes constantly making it difficult to be definitive.
I am trying to stay clear of routine uses of HPLC in the clinic, the problems encountered are much more than chromatographic. The engagement of chromatography, here, is more in the direction of research, purification of radio-labelling products, etc.

Dear Dr. Mueller:

Thanks for your reply. We are aware of HPLC kits from Biorad, etc and are already in touch with them. But what we need is some pointers on which molecules we can analyse using HPLC in a clinical setting.

If you could help us here, we'd greatly appreciate it.

Thanks again.

The determination of cortisol is a typical example of HPLC in the clinic, see J Chromatogr B, 678, 137 (1996). By the time I had this multistep (some call it multidimensional) method at an acceptable stage, the interest for cortisol had evaporated. To use it in the clinical routine it would have to be fully automated. Even though, you could not nearly meet a common reqirement to have up to some 60 samples analyzed in 2h, which an ELISA will do easily. Now, it was shown in the article above, that ELISA, etc., can yield completely wrong values in blood of patients. It appears that physicians take their chances on that.
In short, I can practically relate only negative experience with ascorbic acid, leucotrienes, baclofen, ouabain, oxalic acid, glutathione.
Homocysteine with S-derivatization was reasonable in a near clinidcal setting. However, homocysteine as an indicator for arteriosclerosis is controversial.
Sorry not to be able to do better.

Dear Dr. Mueller:

Thanks for your reply. this is exactly the same problem we are facing in our lab. in our hospital we have a very good transplantation team and hence we are now thinking of assaying cyclosporin in plasma. cortisol is already being assayed in our lab using ELISA.
anyway thank you so much for your advice.
Dr G. Justin

I am not a clinical chromatographer but this may be of some use regarding your electrochemical detector if you do any method development work. The functional groups to look for are aromatic hydroxy compounds, heterocyclic unsaturated nitrogen compounds, keto-enol groups and hydroxy groups adjacent to double bonds in oxidation and nitro groups in reduction. I have included some compounds below which may be of help.
Theophylline LLoQ 10ng
Uric acid LLoQ 1ng
Nicotinic Acid
Paracetamol 200pg
Warfarin LLoQ 2.5ng
Vitamins C (10pg) and E (4ng)
Oestrogens