Abstract: System, including methods, apparatus, and kits, for forming emulsions. The system may include an instrument and a microfluidic chip received by the instrument. The instrument may apply pressure to prospective emulsion phases held by the chip, to drive formation and collection of emulsions in the chip. In some embodiments, the instrument may stop applying pressure to the chip when a change in pressure meeting a predefined condition is detected by the instrument. The change may indicate that an endpoint of droplet generation has been reached.

Abstract: System, including methods, apparatus, compositions, and kits, for making and using compound droplets of a multiple emulsion to supply an amplification reagent, such as a heat-stable DNA polymerase or DNA ligase, to an aqueous phase in which the compound droplets are disposed. The compound droplets may be induced to supply the amplification reagent by heating the multiple emulsion, to achieve hot-start amplification.

Abstract: System, including methods, apparatus, compositions, and kits, for making and using a stabilized emulsion. A method of generating a stabilized emulsion is provided. In the method, an aqueous phase may be provided. The aqueous phase may include an effective concentration of one or more skin-forming proteins. An emulsion may be formed. The emulsion may include droplets of a dispersed phase disposed in a continuous phase, with the aqueous phase being the continuous phase or the dispersed phase. The emulsion may be heated to create an interfacial skin between each droplet and the continuous phase, to transform the droplets into capsules.

Abstract: System, including methods, apparatus, compositions, and kits, for assays with an emulsion including capsules. A method of performing an assay is provided. In the method, an aqueous phase may be provided. The aqueous phase may include a sample and an effective concentration of one or more skin-forming proteins. An emulsion may be formed. The emulsion may include droplets of the aqueous phase disposed in a nonaqueous continuous phase. The emulsion may be heated to create an interfacial skin between each droplet and the continuous phase, to transform the droplets into capsules. Assay data related to the sample may be collected from the capsules.

Abstract: Thermocycling system, including methods and apparatus, for performing a flow-based reaction on a sample in fluid. The system may include a plurality of segments defining at least two temperature regions, and also may include a plurality of heating elements configured to maintain each temperature region at a different desired temperature. At least one of the heating elements may be a thermoelectric cooler operatively disposed to transfer heat to and/or from a temperature region The system further may include a fluid channel extending along a helical path that passes through the temperature regions multiple times such that fluid flowing in the channel is heated and cooled cyclically.

Abstract: System, including methods, apparatus, compositions, and kits, for the mixing of small volumes of fluid by coalescence of multiple emulsions.

Abstract: Methods to improve the performance of an array assay are described. A correlation between fluorescence intensity-related parameters and negative control values of the assay is determined. The parameters are then adjusted as a function of the correlation. As a result, sensitivity of the assay is improved without changes in its specificity.

Abstract: Methods for determination of threshold values of signatures comprised in an assay are described. Each signature enables detection of a target. The methods determine a probability density function of negative samples and a corresponding false positive rate curve. A false positive criterion is established and a threshold for that signature is determined as a point at which the false positive rate curve intersects the false positive criterion. A method for quantitative analysis and interpretation of assay results together with a method for determination of a desired limit of detection of a signature in an assay are also described.

Abstract: A method of rapid, genome and proteome based identification of unknown pathogenic or non-pathogenic organisms in a complex sample. The entire sample is analyzed by creating millions of emulsion encapsulated microdroplets, each containing a single pathogenic or non-pathogenic organism sized particle and appropriate reagents for amplification. Following amplification, the amplified product is analyzed.

Abstract: A system for identifying all of the known and unknown pathogenic or non-pathogenic organisms in a sample. A droplet generator creates droplets from the sample. The droplets constitute sub-nanoliter volume reactors containing the organism sized particles. A lysis device performs lysis of the organisms to release the nucleic acids. An amplifier amplifies the nucleic acids. A fractionater releases the nucleic acids from the droplets. A parallel analyzer identifies all of the known and unknown pathogenic or non-pathogenic organisms in the sample.

Abstract: A system for maintaining a liquid slurry of microbeads for use in biological or chemical analysis comprising providing a flexible bag and filling the flexible bag with a slurry of a liquid and microbeads. One embodiment is an apparatus for maintaining liquid slurries of particles for use in biological or chemical analysis comprising a bag, a liquid contained within the bag, and particles contained within the liquid in the bag.