The present invention provides microfabricated substrates and methods of conducting reactions within these substrates. The reactions occur in plugs transported in the flow of a carrier-fluid.

The invention provides methods for assessing one or more predetermined characteristics or properties of a microfluidic droplet within a microfluidic channel, and regulating one or more fluid flow rates within that channel to selectively alter the predetermined microdroplet characteristic or property using a feedback control.

Apparatuses for preparing a sample are disclosed herein. The apparatuses include a chamber, a first valve at least partially disposed in the first chamber, a second valve at least partially disposed in the first chamber, and a pump comprising an actuator and nozzle.

A fluid handling and delivery system useful in generating a fluid stream in the flow path of microfluidic device.

An assay device and method are described. The assay may involve immobilizing a binding partner (e.g., an antigen or antibody) for an analyte to be detected (e.g., an antibody or antigen) on a portion of a surface of a microfluidic chamber; passing a fluid sample over the surface and allowing the analyte to bind to the binding partner; allowing a metal colloid, e.g., a gold-conjugated antibody, to associate with the bound analyte; flowing a metal solution, e.g., a silver solution, over the surface such as to form an opaque metallic layer; and detecting the presence of said metallic layer, e.g., by visual inspection or by measuring light transmission through the layer, conductivity or resistance of the layer, or metal concentration in the metal solution after flowing the metal solution over the surface.

A fluid handling and delivery system useful in generating a fluid stream in the flow path of microfluidic device.

Cartridges for the isolation of a biological sample and downstream biological assays on the sample are provided, as are methods for using such cartridges. In one embodiment, a nucleic acid sample is isolated from a biological sample and the nucleic acid sample is amplified, for example by the polymerase chain reaction. The cartridges provided herein can also be used for the isolation of non-nucleic acid samples, for example proteins, and to perform downstream reactions on the proteins, for example, binding assays. Instruments for carrying out the downstream biological assays and for detecting the results of the assays are also provided.

The present invention provides microfabricated substrates and methods of conducting reactions within these substrates. The reactions occur in plugs transported in the flow of a carrier-fluid.

The present invention provides microfabricated substrates and methods of conducting reactions within these substrates. The reactions occur in plugs transported in the flow of a carrier-fluid.

An assay method is described, which comprises the steps of immobilizing a binding partner (e.g., an antigen or antibody) for an analyte to be detected (e.g., an antibody or antigen) on a portion of a surface of a microfluidic chamber; passing a fluid sample over the surface and allowing the analyte to bind to the binding partner; allowing a metal colloid, e.g., a gold-conjugated antibody, to associate with the bound analyte; flowing a metal solution, e.g., a silver solution, over the surface such as to form an opaque metallic layer; and detecting the presence of said metallic layer, e.g., by visual inspection or by measuring light transmission through the layer, conductivity or resistance of the layer, or metal concentration in the metal solution after flowing the metal solution over the surface.