Abstract:
A microfluidic element for analysis of a fluid sample having a substrate and a microfluidic transport system having a channel structure enclosed by the substrate and a covering layer. The channel structure comprises a channel with two side walls as well as a chamber that is in fluid communication with the channel. The chamber has a chamber wall with an inlet orifice. The channel comprises a channel section and a valve section adjoining the channel section, wherein the valve section is in fluid communication with the inlet orifice in the chamber wall in such a way that a fluid can flow from the channel through the valve section and into the chamber. The valve section has a fluid transport cross-section, which enlarges in flow direction. The fluid transport cross-section in the valve section is greater than the fluid transport cross-section in the preceding channel section.
Abstract:
A microfluidic test carrier having a substrate, covering layer, and capillary structure formed in the substrate is provided. The capillary structure is enclosed by the substrate and covering layer and comprises a receiving chamber, sample chamber and connection channel between the receiving and sample chambers. The receiving chamber has two boundary surfaces and a side wall, wherein one boundary surface forms the bottom and the other forms the cover. The receiving chamber has a surrounding venting channel and dam between the receiving chamber and venting channel. The dam and venting channel form a capillary stop configured as a geometric valve, through which air from the receiving chamber can escape into the venting channel. The connecting channel between the venting channel outflow and sample chamber inflow controls fluid transport from the receiving chamber into the sample chamber. The capillary stop is configured to prevent autonomous fluid transport from the receiving chamber.