A microfluidic Western blot method and system including a microfluidic western blot method for immunoassay of proteins, the method including introducing a sample including the proteins onto a chip; electrophoretically separating the proteins; binding the separated proteins to beads to form protein-attached beads, the beads being magnetic; flowing the protein-attached beads into a magnetic holding region; applying a magnetic field to the magnetic holding region to fix the protein-attached beads in place within the magnetic holding region; binding primary antibodies to target proteins on the protein-attached beads; binding secondary antibodies to the bound primary antibodies; and detecting the bound secondary antibodies.

A microfluidic Western blot method and system including a microfluidic western blot method for immunoassay of proteins, the method including introducing a sample including the proteins onto a chip; electrophoretically separating the proteins; binding the separated proteins to beads to form protein-attached beads, the beads being magnetic; flowing the protein-attached beads into a magnetic holding region; applying a magnetic field to the magnetic holding region to fix the protein-attached beads in place within the magnetic holding region; binding primary antibodies to target proteins on the protein-attached beads; binding secondary antibodies to the bound primary antibodies; and detecting the bound secondary antibodies.

An electrophoresis apparatus is generally disclosed for sequentially analyzing a single sample or multiple samples having one or more analytes in high or low concentrations. The apparatus comprises a relatively large-bore transport capillary which intersects with a plurality of small-bore separation capillaries and includes a valve system. Analyte concentrators, having antibody-specific (or related affinity) chemistries, are stationed at the respective intersections of the transport capillary and separation capillaries to bind one or more analytes of interest. The apparatus allows the performance of two or more dimensions for the optimal separation of analytes. The apparatus may also include a plurality of valves surrounding each of the analyte concentrators to localize each of the concentrators to improve the binding of one or more analytes of interest.

An electrophoresis apparatus is generally disclosed for sequentially analyzing a single sample or multiple samples having one or more analytes in high or low concentrations. The apparatus comprises a relatively large-bore transport capillary which intersects with a plurality of small-bore separation capillaries and includes a valve system. Analyte concentrators, having antibody-specific (or related affinity) chemistries, are stationed at the respective intersections of the transport capillary and separation capillaries to bind one or more analytes of interest. The apparatus allows the performance of two or more dimensions for the optimal separation of analytes. The apparatus may also include a plurality of valves surrounding each of the analyte concentrators to localize each of the concentrators to improve the binding of one or more analytes of interest.

An immunofixation electrophoresis method including separation of proteins (antigens) by electrophoresis, subjecting the separated proteins to various antisera to cause an antibody-antigen reaction and visualizing the results of the antibody-antigen reaction by staining, including a series of blotting and rehydrating steps with an elevated temperature rehydrating solution to remove unbound proteins (antigens), unreacted antisera, and excess stain.

An immunofixation electrophoresis method including separation of proteins (antigens) by electrophoresis, subjecting the separated proteins to various antisera to cause an antibody-antigen reaction and visualizing the results of the antibody-antigen reaction by staining, including a series of blotting and rehydrating steps with an elevated temperature rehydrating solution to remove unbound proteins (antigens), unreacted antisera, and excess stain.

Electrophoretic separation methods and systems for performing the same are provided. The methods and systems find use in a variety of different electrophoretic separation applications, such as sub-cellular Western blotting of single cells.

Electrophoretic separation methods and systems for performing the same are provided. The methods and systems find use in a variety of different electrophoretic separation applications, such as sub-cellular Western blotting of single cells.

A method is disclosed for fabricating free-standing polymeric nanopillars or nanotubes with remarkably high aspect ratios. The nanopillars and nanotubes may be used, for example, in integrated microfluidic systems for rapid, automated, high-capacity analysis or separation of complex protein mixtures or their enzyme digest products. One embodiment, preferably fabricated entirely from polymer substrates, comprises a cell lysis unit; a solid-phase extraction unit with free-standing, polymeric nanostructures; a multi-dimensional electrophoretic separation unit with high peak capacity; a solid-phase nanoreactor for the proteolytic digestion of isolated proteins; and a chromatographic unit for the separation of peptide fragments from the digestion of proteins. The nanopillars and nanotubes may also be used to increase surface area for reaction with a solid phase, for example, with immobilized enzymes or other catalysts within a microchannel, or as a solid support for capillary electrochromatography-based separations of proteins or peptides.

This invention provides methods and compositions, e.g., to reduce interference from non-specific binding sample constituents in a migration shift assay. Interference due to non-specific binding of sample constituents to an affinity substance (e.g., an affinity molecule or a conjugate of an affinity molecule and a charged carrier molecule) is prevented by, e.g., binding the constituents to charged polymers such as heparin sulfate. The present invention also provides methods to concentrate an analyte of interest with high concentration and to detect the analyte with high sensitivity, and further to optimize the reaction conditions for easily concentrating the analyte. Such objects of the present invention are attained, for example, by concentrating a complex of the analyte and a conjugate which is formed by contacting the analyte in a sample with an affinity molecule bound to a charged carrier molecule such as DNA.