Abstract: A detector arrangement, which comprises a rotatable microfluidic disc and a spectrophotometric detector unit. The arrangement is characterized in that the detector unit is based on surface plasmon resonanc (SPR) and is capable of measuring an analyte within the detection microcavities, each of which is part of a microchannel structure. A microfluidic disc having an axis of symmetry and comprising microchannel structures, each of which has an upstream functional part that is at a shorter radial position than a downstream functional part. The disc is characterized in that there are detection microcavities (DMCs) in at least a part of said microchannel structures, and that each of said DMCs has an SPR surface on an inner wall and a detection detection window extending from the SPR surface to the surface of the disc.

Abstract: The invention relates to a rotary drive adapted for creating liquid flow in rotatable microfluidic discs. A rotary drive for spinning a disc shaped substrate having microfluidic structures formed therein for the flow control of microliter and/or nanoliter volumes of liquid by centrifugal force is suggested, comprising a motor with a spindle having an axis of rotation. A rotary member is connected for rotation with the spindle and driven for rotation relative to a stationary member, the rotary member being formed with a top plane having a centering guide for receiving the disc so as to force a symmetry axis of the disc into alignment with said axis of rotation. A vacuum source is connected with the stationary member and communicating with the rotary member or a part thereof rotating with the rotary member for applying sub-pressure to the disc when spinning the disc about its symmetry axis. Preferably, the rotary member is journalled for contact-free rotation relative to the stationary member.