[Mocook]

Hello all,

How can i calibrate what solvent system is efficient for my mixture, is TLC solvent system practical to use (not the same column tho)? Im attempting to isolate a halogenated porphyrin.

[Arkcon]

I suppose you could try it, if you've used ordinary TLC plates, and your HPLC column is definitely a normal phase column, and you stick to an isocratic run (one eluent, not mixing a gradient over time,) then yes you might get a good starting point for a separation.  You won't have to change too many things, and it will be a start.  But if things are very different, say you're using a reverse phase column, then no, you can't use TLC developing solvent to run the HPLC.  In that case, you can start with a quick literature, or even a Google search for the analyte, to see what sort of conditions you can start at.  In fact, probably best to work with the second option in any case.  I only mentioned the first option in case you were really stubborn.   What column do you have?  And are you certain your HPLC detector can see your analyte?

[Arkcon]

And do try a search on this forum -- the topic of HPLC of dervitized porphyrins did come up once or twice recently.

[Arkcon]

For example, look at this Google result I found for an extremely perflorinated porphyrin.  http://www.researchgate.net/publication/230817114_Synthesis_of_highly_functionalized_fluorinated_porphyrins/file/504635147ec6db2e03.pdf  Its mostly about the synthesis, but they do mention the HPLC analysis.  They used a very short normal phase HPLC column, and they're eluent is simply dichloromethane. (Actually, a variety of non-polar eluents were used, based around dichloromethane, using fairly long columns)

[Arkcon]

And here's a typical reverse-phase method: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1154376/?page=1