A valve includes a stator that has fluidic ports in a seal surface, and a rotor that has a seal surface contacting the stator's seal surface. The rotor has through-holes that extend from the seal surface to a back surface, providing fluidic communication with a conduit disposed adjacent to the back surface of the rotor. A chromatography apparatus includes a sample source, a solvent source having a higher operating pressure than the sample source, and an injector valve. A method of performing chromatography includes loading a sample with a valve in a load-state configuration that disposes a sample source in fluidic communication with a conduit disposed adjacent to a back surface of the rotor, and injecting the loaded sample with the valve in an inject-state configuration that disposes a solvent source in fluidic communication with a column via at grooves adjacent to a front seal surface of the rotor.