December 22, 2024, 04:52:26 PM
Forum Rules: Read This Before Posting


Topic: HPLC - normal and reversed  (Read 6200 times)

0 Members and 1 Guest are viewing this topic.

ciel

  • Guest
HPLC - normal and reversed
« on: December 19, 2005, 12:47:33 PM »
Hello,


could anyone explain why the reversed-phase HPLC is more common used nowadays compared to the normal phase?

Aren't they the same? From what I read, the difference is only that, in the normal phase, the compound that will come out first from the column is the most non-polar one, while in the reversed phase, the first eluted compound is the most polar compound. Is this correct?

Thanks

Offline Albert

  • Lonely Wanderer
  • Retired Staff
  • Sr. Member
  • *
  • Posts: 1050
  • Mole Snacks: +112/-22
  • Gender: Male
  • Half Decent Pharmaceutical Chemist
Re:HPLC - normal and reversed
« Reply #1 on: December 20, 2005, 06:07:21 AM »
Reversed-phase HPLC is widely used beacause it has less problems for what concerns the pollution of the column, compared to normal-phase HPLC.

Moreover, it can be used to analyse drugs (I did it), amino acids and peptides.
In non-aqueous form, it gives you the opportunity to separate fats.

Offline jwesterway

  • Regular Member
  • ***
  • Posts: 20
  • Mole Snacks: +4/-4
  • Gender: Male
Re:HPLC - normal and reversed
« Reply #2 on: January 19, 2006, 09:10:17 PM »
"Normal phase" refers to a np solvent mobile phase is put through a polar stationary phase.
"Reverse phase" is the opposite, a polar solvent mobile with a np stationary.

-Josh

Sponsored Links