Liquid Chromatography

This technical article addresses why formic acid would be specified as an additive for the mobile phase in an HPLC method. Formic or trifluoroacetic acid at 0.1% concentrations are common, especially for LC-MS work. There are a number of reasons for...

PEEK (poly-ether-ether-ketone) tubing and fittings have become a standard part of most HPLC systems today. The flexibility and ease of cutting the tubing, coupled with the convenience of finger-tightened fittings make a combination that is hard to...

This article considers the dilemma that occurs with any discussion regarding method alteration in that it can be open to interpretation.

This technical article discusses the possible effect caused from interactions between changes from different variables.

This technical article discusses the injection volume, column temperature and detector wavelength adjustments.

In this article we’ll look at flow-rate and particle-size adjustments.

In this article, we’ll take a closer look at some of the potential adjustments related to the column.

The second part of this series focuses on the allowable adjustment in the ratio of aqueous (A) to organic (B) components of a reversed-phase mobile phase.

In the first part of this series, an overview of the concept of method adjustment vs method change in reversed-phase HPLC is presented.

PEEK (poly-ether-ether-ketone) fittings and tubing are in widespread use for HPLC applications. The convenience of using your fingers instead of a wrench to tighten the fittings and the flexibility of the tubing make PEEK the material of choice for...

As part of the HPLC Master Classes that I teach, I start each class by gathering questions or topics that the attendees would like to know more about. In a recent class in London, one of the topics was the causes of excessive retention – a method in...

This technical article takes a closer look at the influence of temperature on the separation.

In the previous three instalments of this series ('#7: Fundamental Resolution Equation, Part 1', '#8: Fundamental Resolution Equation, N', '#9: Fundamental Resolution Equation – Alpha'), we’ve looked at the fundamental resolution equation

In the previous two articles ('#7 Fundamental Resolution Equation, Part 1' and '#8 Fundamental Resolution Equation, N'), we’ve looked at the fundamental resolution equation

In the previous article we began our study of the fundamental resolution equation