There are many issues associated with the development of assays within a HILIC mode. This has often been an activation energy that is seen as too high for some chromatographers and as a result the technique has struggled to become established in some laboratories. This is exasperated by a view from some that HILIC chromatography is generic and that all HILIC columns will behave in a similar fashion. As in reversed phased chromatography this is clearly not the case and different columns will have different selectivities towards different compounds. As well as understanding the effect that column chemistry can have on the separation, there is a whole array of other variables that need to be considered including:

• Organic solvent content
• Buffer concentration
• Mobile phase pH
• Column temperature

This presentation will look at column selection and how to ensure that the correct stationary phase is chosen for a particular separation. A range of columns will be evaluated including bare silica, anionic, cationic and zwitterionic phases to determine their favoured retention and separation mechanism for different types of analytes. Data will also be presented which will look at some common issues associated with HILIC chromatography, and hopefully this will address some of the high activation energies associated with this technology.