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.

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.

A molecular detection chip including a metal oxide silicon-field effect transistor (MOSFET) on sidewalls of a micro-fluid channel and a molecular detection device including the molecular detection chip are provided. A molecular detection method, particularly, qualification methods for the immobilization of molecular probes and the binding of a target sample to the molecular probes, using the molecular detection device, and a nucleic acid mutation assay device and method are also provided. The formation of the MOSFET on the sidewalls of the micro-fluid channel makes easier to highly integrate a molecular detection chip. In addition, immobilization of probes directly on the surface of a gate electrode ensures the molecular detection chip to check for the immobilization of probes and coupling of a target molecule to the probes in situ.

A method for covering a set of open microchannel structures which are fabricated on a planar surface made of plastics and which comprise two or more part areas that have different surface characteristics. The method comprises the steps of: a) providing the surface comprising the set of microchannel structures; b) providing a lid-forming sheet having on one side an even layer of a thermoglue; c) applying the side of the sheet having the thermoglue against the surface carrying the microchannel structure; d) heating the assembly created in step (c) to selectively liquefy the hot-melt adhesive while at the same time pressing the sheet material and the planar surface of the substrate together; e) permitting the resulting laminate-covered microchannel structure to cool. An assembly comprising (a) a planar substrate, the surface of which has a set of one or more open microchannel structures each of which comprises part areas representing different functionalities, and (b) a lid-forming material covering said set of microchannel structures and having one or more openings going from a microchannel structure to ambient atmosphere. The assembly is characterized in that the joint between said surface and said sheet material is a thermoglue that possibly has been cured.

A microfluidic disc having one or more enclosed microchannel structures, and the microchannel structures are intended to be used for transport of transporting liquids. The device is characterized in that at least a part of the inner walls of each of one or more microchannel structures are treated with a gas plasma having one or more organic precursor compounds.