Abstract: This invention generally relates to methods and systems for dispensing a droplet, in particular a picolitre volume droplet containing one or more entities.

Abstract: The present invention provides a surfactant having a formula selected from the group consisting of: B—((X)x—(CH2)a-A)n(VI), (A-(CH2)a—(X)x—B—(X)x—(CH2)a-A)n (IV), (A-(CH2)a—(X)x—B)n (V), and (B)n—(X)x—(CH2)a-A (VII), wherein A is a perfluoropolyether; a is a positive integer; X is either a covalent bond or a linking group; x is a positive integer; B is a polyalkylene oxide unit; n is a positive integer greater than 1 and, in compounds comprising more than one A, B, X, a and x, each may be the same or different. The present invention also relates to methods of making such surfactants, uses of such surfactants and emulsions comprising such surfactants.

Abstract: A method for aligning sequences of droplets in streams of an emulsion comprising target droplets and tag droplets, a tag droplet comprising first and second tags. A target droplet is split into first and second target droplets and a tag droplet is split into first and second tag droplets. Each of the first and second tag droplets comprise the first and second tags. The first target droplet and first tag droplet are in a first stream of droplets, and the second target droplet and second tag droplet are in a second stream of droplets. The method detects the first tag droplets and first target droplets in the first stream and the second tag droplets and second target droplets in the second stream, determines a first sequence of droplets in the first stream and a second sequence of droplets in the second stream, and compares these to align the sequences.

Abstract: A method for aligning sequences of droplets in streams of an emulsion comprising target droplets and tag droplets, a tag droplet comprising first and second tags. A target droplet is split into first and second target droplets and a tag droplet is split into first and second tag droplets. Each of the first and second tag droplets comprise the first and second tags. The first target droplet and first tag droplet are in a first stream of droplets, and the second target droplet and second tag droplet are in a second stream of droplets. The method detects the first tag droplets and first target droplets in the first stream and the second tag droplets and second target droplets in the second stream, determines a first sequence of droplets in the first stream and a second sequence of droplets in the second stream, and compares these to align the sequences.

Abstract: Instruments and cartridges for processing droplets in emulsions containing biological entities such as cells. A method of such processing comprises providing a plurality of the entities in a fluid; preparing a droplet from the fluid; determining whether the droplet contains one or more entities of said plurality of entities, or whether said droplet does not contain a said entity; sorting said droplet dependent on an outcome of the determination; and dispensing the sorted droplet into a reservoir. The dispensing may comprise identifying and extracting the sorted droplet from a first fluidic flow path of said fluid by transferring the sorted droplet from into a second fluidic flow path and then ejecting the sorted droplet into a reservoir by applying pressure to the second fluidic flow path. The droplet contents may be tracked so that the contents of an individual droplet can be sorted, selectively dispensed, and retrieved.

Abstract: A microfluidic structure for spacing out and aligning entities in an aqueous suspension is provided. The structure comprises: a channel for guiding entities in an aqueous suspension; a first comb of first inlets arranged on a first side of the channel for introducing a spacing medium into the channel; and a second comb of second inlets arranged on a second side of the channel for introducing the spacing medium into the channel; wherein the first side is opposite the second side, and wherein one of the first inlets has a corresponding, respective one of the second inlets at a substantially similar longitudinal position along the channel.

Abstract: A method for aligning sequences of droplets in streams of an emulsion comprising target droplets and tag droplets, a tag droplet comprising first and second tags. A target droplet is split into first and second target droplets and a tag droplet is split into first and second tag droplets. Each of the first and second tag droplets comprise the first and second tags. The first target droplet and first tag droplet are in a first stream of droplets, and the second target droplet and second tag droplet are in a second stream of droplets. The method detects the first tag droplets and first target droplets in the first stream and the second tag droplets and second target droplets in the second stream, determines a first sequence of droplets in the first stream and a second sequence of droplets in the second stream, and compares these to align the sequences.

Abstract: We describe a method comprising: providing a droplet comprising a plurality of constituents, splitting said droplet into a first droplet and a second droplet, wherein said first droplet comprises a first fraction of said plurality of constituents and said second droplet comprises a second fraction of said plurality of constituents, analysing said constituents of said first fraction of said plurality of constituents in said first droplet, and sorting said second droplet dependent on an outcome of said analysis.

Abstract: A method of label-free cell or particle sorting in a microfluidic device includes providing a stream of aqueous droplets in oil in a channel of the microfluidic device, wherein at least some of the droplets include cells or particles and illuminating the stream from a first direction. Then, one detects scattered light from cells or particles within said aqueous droplets in a second direction. Next, one determines a number of the cells or particles in each droplet from the scattered light and sorts the aqueous droplets into differentiated streams. Notably, the refractive index of said oil is modified to closely match a refractive index of the aqueous droplets to reduce light scattered from boundaries of the droplets. A volume of the droplets can also controlled.

Abstract: We describe a method comprising: providing a droplet comprising a plurality of constituents, splitting said droplet into a first droplet and a second droplet, wherein said first droplet comprises a first fraction of said plurality of constituents and said second droplet comprises a second fraction of said plurality of constituents, analysing said constituents of said first fraction of said plurality of constituents in said first droplet, and sorting said second droplet dependent on an outcome of said analysis.

Abstract: The present invention provides an emulsion for sorting droplets in a microfluidic device, the emulsion comprising: a discontinuous aqueous phase; and a continuous oil phase; wherein said aqueous phase comprises at least one analyte, said oil phase comprises a fluorous oil and a refractive index modifying compound comprising at least one aromatic ring, and the refractive index of said aqueous phase and the refractive index of said oil phase are substantially matched.

Abstract: This invention relates to methods and systems for providing chemical and/or biological materials. Thus we describe a method of providing a chemical or biological material in a quantized form, the method comprising: preparing an emulsion comprising a plurality of microdroplets each holding a controlled amount of said material; storing said chemical or biological material in said microdroplets in said emulsion; transferring a portion of said emulsion microdroplets to a container for transportation; transporting said container to a user of said material, wherein said user receives said material in a quantized form in said microdroplets of said emulsion; and de-emulsifying said received microdroplets containing said material in quantized form to extract said material for subsequent use.

Abstract: A flow cell for a microfluidic device can include a chamber, first microfluidic entry and exit channels, second microfluidic entry and exit channels, a first electrode, and a second electrode. A microfluidic device can include a microfluidic channel, a laser to excite fluorescent material, and a detector to detect fluorescence emission. Methods of merging a droplet from an emulsion in to a second stream of fluid and of detecting a content of a droplet in a stream are further disclosed.

Abstract: This invention relates to methods and systems for providing chemical and/or biological materials. Thus we describe a method of providing a chemical or biological material in a quantised form, the method comprising: preparing an emulsion comprising a plurality of microdroplets each holding a controlled amount of said material; storing said chemical or biological material in said microdroplets in said emulsion; transferring a portion of said emulsion microdroplets to a container for transportation; transporting said container to a user of said material, wherein said user receives said material in a quantised form in said microdroplets of said emulsion; and de-emulsifying said received microdroplets containing said material in quantised form to extract said material for subsequent use.