A microfluidic detection device provides reduced dispersion of axial concentration
gradients in a flowing sample. The microfluidic detection device includes a cell
body and a flow path through the cell body. The flow path has an inlet segment,
an outlet segment, and a central segment, which forms a detection cell. The central
segment is located between and at an angle with both the inlet segment and the
outlet segment. The central segment has a first junction with the inlet segment
and a second junction with the outlet segment. The cell body contains two arms
that can transmit light to and from the detection cell. At least a portion of a
first arm is located in the first junction and at least a portion of a second arm
is located in the second junction. The portions of the arms located in the junctions
are situated so that fluid entering or exiting the central segment of the flow
path flows around the outer surface of one of the portions. By ensuring that the
flow velocity is high near the walls both at the beginning and at the end of the
conduit, the configuration serves to counteract dispersion caused by the normal
parabolic velocity profile of flow through a cylindrical conduit, where the fluid
velocity is highest at the center. In addition, the configuration promotes efficient
sweeping of the entire volume between the two arms. A method for manufacturing
the microfluidic detection device is also provided.