Abstract: The present disclosure provides a method for detection of an analyte in a sample, where the sample is introduced into an analytic chamber along with droplets of an emulsion or gel beads. In another aspect, the present disclosure provides designs for formulations of emulsion drops or gel beads such that they are useful for detection of analytes in a massively parallel manner. Formulations that contain specific combinations of fluorescent particles allow optical determination of the identity of each fluorescent particle. The combinations are based on particle fluorescence emission wavelength, fluorescence excitation wavelength, and particle count.

Abstract: The present disclosure in some aspects provides methods for the controlled merging of emulsion droplets, which can be used to assemble useful compositions such as droplets (e.g., stabilized micelles) containing a precise combination of analytes and/or analytical reagents. In some embodiments, disclosed herein is a method, e.g., for detecting the presence/absence, a level or amount, and/or an activity of an analyte in a sample, comprising merging two or more emulsion droplets such that an interaction between an analyte and an analyte-interacting reagent occurs in the merged droplet. The two or more emulsion droplets may be merged using a method for the controlled merging of emulsion droplets disclosed herein.