Carmen T. Santasania

Fluorinated stationary phases, especially those including a pentafluorophenyl (PFP) moiety, have become popular alternatives to the more traditional alkyl (C8 and C18) phases. Many modern column lines have, in fact, been initially introduced with the standard C18 and a PFP phase because of their orthogonality. In this instalment, the differences between alkyl phases and PFP phases are discussed in terms of fundamental interactions. The origin of the interactions is also interpreted to better understand how analysts can use and control them to develop effective and rugged analytical methods.

Ascentis Express 5 micron columns provide a new choice for improving the performance of traditional HPLC systems. Based on Fused-Core particle technology, Ascentis Express provides the benefits of high speed and high efficiencies without the concerns of smaller particle columns. Due to the high efficiencies at low backpressures, Ascentis Express 5 micron can benefit conventional HPLC users with no drawbacks.