Patent ID: 8257586

Claim:
A valve arrangement for providing a switchable fluid connection between a fluid delivery system for driving a mobile phase and a stationary phase adapted for separating compounds of a sample fluid comprised in the mobile phase, comprising: a first valve comprising a first port adapted to be coupled to the fluid delivery system, a second port, and a third port, wherein the first valve is adapted to switch, in a first switch transition, from a first state wherein the first port is coupled with the second port, over a second state wherein the first port, the second port and the third port are coupled altogether, to a third state wherein the first port is coupled with the third port, a second valve comprising a fifth port adapted to be coupled to the stationary phase, a sixth port, and a seventh port, wherein the second valve is adapted to switch, in a second switch transition, from a fourth state wherein the fifth port is coupled with the sixth port, to a fifth state wherein the fifth port is coupled with the seventh port, a first fluid path connecting the second port and the sixth port, and a second fluid path connecting the third port and the seventh port, wherein the second fluid path comprises a sample introduction path adapted for introducing the sample fluid into the mobile phase.