4.3.1.1.2 Electrokinetic Injection

In electrokinetic injection, a voltage 3-5 times lower than that required for separation is applied between the input and output reservoirs for approximately 10-30 seconds. Sample is loaded according to the difference in voltage across the capillary and the amount of each individual analyte that is loaded is dependent on the analyte's electrophoretic mobility. As such, electrokinetic injection cannot be used quantitatively. This technique is useful in situations where the media in capillary is very viscous making hydrodynamic injection difficult. Additionally, it requires no extra instrumentation.

Figure 4.6 Electrokinetic injection setup