Device and Method for Isolation and Detection of Soluble or Particulate Analytes from Complex Background Matrices

Analyte detection systems and related methods are generally described. In some embodiments, an analyte testing system may rapidly and sensitively sense analyte (e.g., any biological and/or chemical analyte) from a testing sample in a fluid container, which may also include one or more populations of particles coated with/including binding ligands, moieties, and/or coatings for binding to analyte, if present. An external force may be applied to the container to urge the particles to move through the fluid faster than a rate determined by diffusion. The particles may subsequently settle on a target surface. The particles disposed on the surface may be characterized to determine the presence of the analyte. In some embodiments, a sequence of images of particles bound specifically and nonspecifically to the surface may be analyzed to determine a relative displacement of the particles, and subsequently, analyte concentration of the testing sample.