Ion exchange chromatography (IEX) and hydrophobic interaction chromatography (HIC) methods have traditionally been developed studying one variable at a time. This limits the potential power of these purification techniques because two variables, ion concentration and pH, are intertwined and these two parameters can both contribute significantly to a purification process.

IEX and HIC method development would be much more powerful is two variables are tested simultaneously. For example setting up a matrix of experiments where a 96-well plate consists of two gradients, pH on the Y-axis and a salt gradient on the X-axis would only be possible using the PhyTip column technology.