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.