Abstract: Devices, systems, methods, and compositions of matter can track and/or identify a library of elements, particularly for use with fluids, particulates, cells, and the like. Signals from one or more semiconductor nanocrystals may be combined to define spectral codes. Separation of signal wavelengths within dedicated wavelength ranges or windows facilitates differentiation of spectral codes, while calibration signals within the spectral codes can avoid ambiguity. Modeling based on prior testing can help derive libraries of acceptable codes.

Abstract: Devices, systems, kits, and methods for detecting and/or identifying a plurality of spectrally labeled bodies well-suited for performing multiplexed assays. By spectrally labeling the beads with materials which generate identifiable spectra, a plurality of beads may be identified within the fluid. Reading of the beads is facilitated by restraining the beads in arrays, and/or using a focused laser.

Abstract: Immunochromatographic test strip assays which employ semiconductor nanocrystals as detectable labels are disclosed, as are methods for detecting and quantifying one or more analytes of interest in a test sample using those assays. The test strips of the present invention permit detection and quantitation of one or more analytes of interest present in a test sample suspected of containing them, by using more than one semiconductor nanocrystal as a detectable label, each of which emits exhibits a unique emission peak.