Devices, systems, and methods for conducting sandwich assays using sedimentation

摘要

Embodiments of the present invention are directed toward devices, systems, and method for conducting sandwich assays using sedimentation. In one example, a method includes generating complexes on a plurality of beads in a fluid sample, individual ones of the complexes comprising a capture agent, a target analyte, and a labeling agent. The plurality of beads including the complexes may be transported through a density media, wherein the density media has a density lower than a density of the beads and higher than a density of the fluid sample, and wherein the transporting occurs, at least in part, by sedimentation. Signal may be detected from the labeling agents of the complexes.

主权项

1. A method of conducting a sandwich assay, the method comprising:
providing a fluid sample in a channel on a microfluidic disk, the fluid sample comprising a plurality of beads having complexes formed thereon, individual ones of the complexes comprising a capture agent, a target analyte, and a labeling agent, the fluid sample further comprising free labeling agent; providing a density media from a media reservoir to a detection region of the microfluidic disk by applying a first centrifugal force, the media reservoir on the microfluidic disk and in fluid communication with the detection region, the detection region fluidly coupled to the channel, wherein the density media has a density within a range, an upper bound of the range being lower than a density of the plurality of beads and a lower bound of the range being higher than a density of the fluid sample; spinning the microfluidic disk to apply a second centrifugal force on the plurality of beads, the first and second centrifugal forces being different; transporting the plurality of beads including the complexes through the density media, wherein the free labeling agent is restricted from transport through the density media, and wherein a first plurality of beads having a first property is transported to a first distinct detection location and a second plurality of beads having a second property different than the first property is transported to a second distinct detection location; detecting a signal from the labeling agents of the complexes; and generating an electronic detection signal based, at least in part, on the signal detected from the labeling agents.