Establishment and evaluation of comprehensive two-dimensional liquid chromatography (IEC/RP)

A two-dimensional liquid chromatography is established with ion-exchange chromatography (IEC) followed by reversed phase liquid chromatography (RP). The interface is a ten-port two-position switching valve coupled with two parallel RP columns. After splitting the IEC effluent with a ratio of 10 : 1 (volume ratio), the IEC profile and the RP profile were obtained simultaneously. The system is evaluated with 5 standard proteins, which cannot be resolved in either of IEC or RP mode alone but can be resolved by the comprehensive two-dimensional liquid chromatography. The total peak capacity of this system is calculated to be 189.