Provided herein are microfluidic devices for analyzing samples. In one aspect, the microfluidic device includes a body structure having a droplet compression chamber, a sieve structure in fluid communication with the droplet compression chamber, which sieve structure comprises an array of protrusions that extend from at least one surface of the body structure and define at least a portion of one or more fluidic circuits, and a port at least partially disposed in the body structure. Other aspects include kits, methods, systems, computer readable media, and related aspects for analyzing samples.

The invention relates to a cellular microcompartment comprising successively, organized around a lumen, at least one layer of pluripotent cells, an extracellular matrix layer and an outer hydrogel layer. The invention also relates to processes for preparing such cellular microcompartments.

Method and apparatuses for forming gel droplets including biological tissue (e.g., cells), and in particular, methods and apparatuses for removing oil from the gel droplets comprising dissociated cells (including micro-organospheres) are described herein. Although it is beneficial to use oil in the formation of these gel droplets, and particularly micro-organospheres, oil may inhibit growth and survival of the cells within the gel droplets. The methods and apparatuses described herein may permit the removal of oil and may enhance survival and quality of the resulting gel droplets.

Provided herein are devices and methods that enable co-incubation of microorganisms. Also provided are methods of making such devices for co-incubation of microorganisms, and various applications of such devices.

Methods for forming arrays of droplets, and associated arrays of droplets, are generally provided.

The invention relates to an apparatus for producing a droplet assembly, which apparatus comprises: at least one droplet generator suitable for generating droplets of a viscous droplet medium; a droplet receiving region which is moveable relative to the at least one droplet generator; a temperature controller; and a control unit, which control unit is adapted to control the dispensing of droplets from the at least one droplet generator and the movement of the droplet receiving region relative to the at least one droplet generator, wherein the apparatus is adapted to produce a droplet assembly in the droplet receiving region, wherein the droplet assembly comprises a plurality of droplets, wherein each of said droplets comprises (i) a droplet medium, and (ii) an outer layer of amphipathic molecules around the surface of the droplet medium.

Describe is a method for screening mutant prokaryotic cells to identify producers of a cytotoxic agent active against a target cell, the method comprising the steps of: (a) providing cells of a producer prokaryotic species; (b) generating a pool of mutant producer cells by transposon mutagenesis of the cells of step (a) with an activating transposon (TnA), wherein the TnA comprises an outward-facing promoter (TnAP) capable of increasing transcription of a gene at or near its insertion site in the DNA of said producer cells; (c) co-encapsulating individual members of the pool of step (b) with one or more target cells in microdroplets, the microdroplets comprising a volume of aqueous growth media suspended in an immiscible carrier liquid, thereby generating a library of microdroplets each comprising a single mutant producer cell and one or more target cell(s); (d) incubating the microdroplet library of step (c) under conditions suitable for co-culture of the single mutant producer cell and target cell(s) to produce a library of microcultures, whereby mutant producer cells producing a cytotoxic agent active against the target cell(s) outgrow target cells in each microculture; and (e) screening the library of microcultures of step (d) for microcultures in which target cells have been outgrown or overgrown to extinction by mutant producer cells.

Described is a method for identifying a gene which mediates antibiotic sensitivity or resistance in a target bacterium, the method comprising the steps of: (a) generating a pool of mutant target bacteria by transposon mutagenesis with an activating transposon (TnA), wherein the TnA comprises an outward-facing promoter (TnAP) capable of increasing transcription of a gene at or near its insertion site in the DNA of said target cells; (b) generating a control microdroplet library by encapsulating individual members of the pool of step (a) in microdroplets, the microdroplets comprising a volume of aqueous growth media suspended in an immiscible carrier liquid, each microdroplet comprising a single mutant target cell; (c)generating a test microdroplet library by encapsulating individual members of the pool of step (a) in microdroplets, the microdroplets comprising a volume of aqueous growth media containing the antibiotic and suspended in an immiscible carrier liquid, each microdroplet comprising a single mutant target cell; (d) incubating the control and test microdroplet libraries to produce control and test microcultures; and (e) comparing the distribution of TnA insertions between control and test microcultures to identify a gene which mediates antibiotic sensitivity or resistance in said target bacterium.

A low-cost method is provided for fabricating a nano-droplet plate with surface features having re-entrant (anvil-like) geometries capable of holding droplets of a precise, predetermined volume. Such structures are useful for a variety of applications, including cull culturing, high-throughput screening of therapeutics and as microwells.

Systems are provided that provide an extended measuring range for biological assays, such as immunoassays. In one embodiment a plurality of discrete test sites is used. Data for the proportion of test sites that indicate the presence of the analyte of interest and data that provides a statistical value for a signal generated by the population of discrete test sites is gathered. The results of these digital and statistical approaches are aggregated to provide an extended dynamic range.