Microfluidic detection device having reduced dispersion and method for making same

Abstract

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.