A sample separation device for separating a fluidic sample includes a fluid drive for driving a mobile phase and the fluidic sample when injected in the mobile phase, a sample separation unit for separating the fluidic sample in the mobile phase, and a control unit configured for bracketing the fluidic sample between two mobile phase portions of the mobile phase. At least one of the mobile phase portions is arranged directly next to the fluidic sample and has a higher solvent strength compared to a solvent of the fluidic sample.