Dear all,
I have developed an analytical method on a 55*2 mm HPLC column with 3 µm silica particle. I use a flow rate of 500 µl/min to make fast analysis (ca. 1 min).
Somebody told me that this is not real chromatography because the reduced h value (H/dp) is approximatly 6 instead of being around 2.
What do you think about that?

Chromatography is seperation, did you seperate your compounds? If you did, then you have performed "real" chromatography.

As others have said on sci.chem.analytical and they whole point is "Can you reproducibly, accurately, and transferably (i.e. different operators, different instruments) detect and quantitate the compound of interest?" If the answer is yes, then you can confidently tell your colleague to pound sand.

Thank you

Your colleague had a point regarding the efficiency of the chromatogarphy. You'll see optimum column efficiency at reduced H of 2-3. You have sacrificed efficiency for speed using 0.5mL/min flow on 3um and 2mm ID column.

Nevertheless, you seems to have sufficient efficiency for your separation. You are indeed doing a GOOD chromatography for your application, maybe not the best possible chromatography in terms of optimum column length, flow rate.