Patent ID: 7295320

Claim:
A detector arrangement comprising: a) a rotary member having an axis of rotation, said member comprises: (i) one or more microfluidic discs, each disc comprises a plurality of essentially equal and enclosed microchannel structures which are designed for permitting liquid transport by centrifugal force created by spinning the disc around the axis of rotation, and a first plurality of surface plasmon resonance measuring cells (SPR-MCs), each SPR-MCs comprises a detection microcavity (DMC), wherein an SPR surface in an inner wall of the DMC and at least a part (P 1 ) of a detection window (DW) that stretches from the SPR surface to an outer surface of the disc, and said outer surface of P 1 for all SPR-MCs are at the same radial distances (ii) a rotatable disc holder comprising the remaining part (P 2 ) of each of the DWs, b) a non-rotatable SPR detector comprising (i) a light source (LS), and (ii) a light detecting subunit (LDS), c) a beam path comprising (i) an incident beam path (ibp) going from LS to one of the SPR surfaces via the DW associated with this SPR surface, and (ii) a reflected beam path (rpb) going from the same SPR surface to LDS via said DW, the SPR-MCs being interchangeable by rotating said rotatory member.