Abstract: Techniques Nuc-seq, Div-Seq, and Dronc-Seq are allow for unbiased analysis of any complex tissue. Nuc-Seq, a scalable single nucleus RNA-Seq method, can sensitively identify closely related cell types, including within the adult hippocampus. Div-seq combines Nuc-Seq with EdU-mediated labeling of proliferating cells, allowing tracking of transcriptional dynamics of newborn neurons in an adult neurogenic region in the hippocampus. Dronc-Seq uses a microfluidic device to co-encapsulate individual nuclei in reverse emulsion aqueous droplets in an oil medium together with one uniquely barcoded mRNA-capture bead.

Abstract: Parallel uses of microfluidic methods and devices for focusing and/or forming discontinuous sections of similar or dissimilar size in a fluid are described. In some aspects, the present invention relates generally to flow-focusing-type technology, and also to microfluidics, and more particularly parallel use of microfluidic systems arranged to control a dispersed phase within a dispersant, and the size, and size distribution, of a dispersed phase in a multi-phase fluid system, and systems for delivery of fluid components to multiple such devices.

Abstract: The present disclosure discloses an engineered liposome with cell membrane proteins to reduce melanosome transport and a preparation method thereof, and belongs to the technical field of cosmetics and biomedicine. The present disclosure provides the engineered liposome with cell membrane proteins to reduce melanosome transport and the preparation method thereof, which is easy to operate, requires no large-scale equipment, has few additives, and a preparation process is simple and environmentally friendly. The biomimetic liposome can significantly inhibit melanin transport. The fluorescence intensity of melanosomes in keratinocytes is found to decrease by 3.5-fold in a co-culture test of melanocytes and the keratinocytes, indicating that this biomimetic liposome is very effective in inhibiting accumulation of melanin in skin keratinocytes.

Abstract: The present invention generally relates to droplets and/or emulsions, such as multiple emulsions. In some cases, the droplets and/or emulsions may be used in assays, and in certain embodiments, the droplet or emulsion may be hardened to form a gel. In some aspects, a heterogeneous assay can be performed using a gel. For example, a droplet may be hardened to form a gel, where the droplet contains a cell, DNA, or other suitable species. The gel may be exposed to a reactant, and the reactant may interact with the gel and/or with the cell, DNA, etc., in some fashion. For example, the reactant may diffuse through the gel, or the hardened particle may liquefy to form a liquid state, allowing the reactant to interact with the cell. As a specific example, DNA contained within a gel particle may be subjected to PCR (polymerase chain reaction) amplification, e.g., by using PCR primers able to bind to the gel as it forms. As the DNA is amplified using PCR, some of the DNA will be bound to the gel via the PCR primer.

Abstract: The present invention generally relates to emulsions, and more particularly, to multiple emulsions. In one aspect, multiple emulsions are formed by urging a fluid into a channel, e.g., by causing the fluid to enter the channel as a “jet.” Side channels can be used to encapsulate the fluid with a surrounding fluid. In some cases, multiple fluids may flow through a channel collinearly before multiple emulsion droplets are formed. The fluidic channels may also, in certain embodiments, include varying degrees of hydrophilicity or hydrophobicity. As examples, the fluidic channel may be relatively hydrophilic upstream of an intersection (or other region within the channel) and relatively hydrophobic downstream of the intersection, or vice versa. In some cases, the average cross-sectional dimension may change, e.g., at an intersection. For instance, the average cross-sectional dimension may increase at the intersection.

Abstract: The present invention is generally related to systems and methods for producing droplets. The droplets may contain varying species, e.g., for use as a library. In some cases, at least one droplet is used to create a plurality of droplets, using techniques such as flow-focusing techniques. In one set of embodiments, a plurality of droplets, containing varying species, can be divided to form a collection of droplets containing the various species therein. A collection of droplets, according to certain embodiments, may contain various subpopulations of droplets that all contain the same species therein. Such a collection of droplets may be used as a library in some cases, or may be used for other purposes.

Abstract: The present invention is generally related to systems and methods for producing a plurality of droplets. The droplets may contain varying species, e.g., for use as a library. In some cases, the fluidic droplets may be rigidified to form rigidified droplets (e.g., gel droplets). In certain embodiments, the droplets may undergo a phase change (e.g., from rigidified droplets to fluidized droplets), as discussed more herein. In some cases, a species may be added internally to a droplet by exposing the droplet to a fluid comprising a plurality of species.

Abstract: Transcriptomes of individual neurons provide rich information about cell types and dynamic states. However, it is difficult to capture rare dynamic processes, such as adult neurogenesis, because isolation from dense adult tissue is challenging, and markers for each phase are limited. Here, Applicants developed Nuc-seq, Div-Seq, and Dronc-Seq. Div-seq combines Nuc-Seq, a scalable single nucleus RNA-Seq method, with EdU-mediated labeling of proliferating cells. Nuc-Seq can sensitively identify closely related cell types within the adult hippocampus. Div-Seq can track transcriptional dynamics of newborn neurons in an adult neurogenic region in the hippocampus. Dronc-Seq uses a microfluidic device to co-encapsulate individual nuclei in reverse emulsion aqueous droplets in an oil medium together with one uniquely barcoded mRNA-capture bead. Finally, Applicants found rare adult newborn GABAergic neurons in the spinal cord, a non-canonical neurogenic region.

Abstract: A user-replaceable filter unit may include a combination of an activated carbon fiber filter and an electrically charged fiber filter. The replaceable filter unit may be secured in a housing and positioned within a larger filtering system, for example a bottle, container, pitcher, etc.

Abstract: The present disclosure generally relates to sugar reduction in foods and, in some aspects, to enzyme-polymer conjugated particles for food and other applications. Certain aspects of the disclosure are directed to compositions for reducing sugar content and/or producing dietary fiber within food products during or after consumption (e.g., in a subject's gastrointestinal (GI) tract), while maintaining the sweetness and flavor of the sugar in food products upon consumption (e.g., in a subject's mouth). For example, in one set of embodiments, a composition may comprise a particle comprising an enzyme capable of converting a sugar into a relatively non-digestible form (e.g., a polymer), optionally an inhibitor that reversibly inhibits the enzyme from converting the sugar, and optionally an additive capable of associating with the inhibitor. The composition may be used for in situ conversion of sugars upon exposure to an environment condition (e.g., pH and/or temperature) in the GI tract.

Abstract: Methods for analyzing DNA-containing samples are provided. The methods can comprise isolating a single genomic equivalent of DNA from the DNA-containing sample to provide a single isolated DNA molecule. The single isolated DNA molecule can be subjected to amplification conditions in the presence of one or more sets of unique molecularly tagged primers to provide one or more amplicons. Any spurious allelic sequences generated during the amplification process are tagged with an identical molecular tag. The methods can also include a step of determining the sequence of the one or more amplicons, in which the majority sequence for each code is selected as the sequence of the single original encapsulated target. The DNA-containing sample can be a forensic sample (e.g., mixed contributor sample), a fetal genetic screening sample, or a biological cell.

Abstract: The present invention generally relates to microfluidic devices. In some aspects, various entities, such as droplets or particles, may be contained within a microfluidic device, e.g., within collection chambers or other locations within the device. In some cases, the entities may be released from such locations, e.g., in a sequential pattern, or an arbitrary pattern. In some cases, the entities may be imaged, reacted, analyzed, etc. while contained within the collection chambers. Other aspects are generally directed to methods of making or using such devices, kits involving such devices, or the like.

Abstract: The present invention generally relates to a controlled fluidic device to develop spatially complex environments to enhance the rate of evolution in cell populations. The method further provides an enhanced understanding in the emergence, for example, drug resistance during cancer chemotherapy.

Abstract: The present invention generally relates to microfluidics and labeled nucleic acids. For example, certain aspects are generally directed to systems and methods for labeling nucleic acids within microfluidic droplets or other compartments, for instance, arising from a cell. In one set of embodiments, particles may be prepared containing oligonucleotides that can be used to determine target nucleic acids, e.g., attached to the surface of the particles. The oligonucleotides may include “barcodes” or unique sequences that can be used to distinguish nucleic acids in a droplet from those in another droplet, for instance, even after the nucleic acids are pooled together or removed from the droplets. Certain embodiments of the invention are generally directed to systems and methods for attaching additional or arbitrary sequences to the nucleic acids within microfluidic droplets or other compartments, e.g.

Abstract: The present invention provides capsules having a shell of material that comprises an assembly of a protein, and the capsule is optionally provided with a network of material within the shell that is an assembly of the protein. The assembly of the protein is obtained or obtainable by the aggregation of the protein, optionally together with another protein. The assembly is a non-covalent assembly of a protein.

Abstract: A system and method are provided for harvesting target biological substances. The system includes a substrate and a first and second channel formed in the substrate. The channels longitudinally extending substantially parallel to each other. A series of gaps extend from the first channel to the second channel to create a fluid communication path passing between a series of columns with the columns being longitudinally separated by a predetermined separation distance. The system also includes a first source configured to selectively introduce into the first channel a first biological composition at a first channel flow rate and a second source configured to selectively introduce into the second channel a second biological composition at a second channel flow rate. The sources are configured to create a differential between the first and second channel flow rates to generate physiological shear rates along the second channel that are bounded within a predetermined range.

Abstract: The invention describes a method for the synthesis of compounds comprising the steps of: (a) compartmentalising two or more sets of primary compounds into microcapsules; such that a proportion of the microcapsules contains two or more compounds; and (b) forming secondary compounds in the microcapsules by chemical reactions between primary compounds from different sets; wherein one or both of steps (a) and (b) is performed under microfluidic control; preferably electronic microfluidic control The invention further allows for the identification of compounds which bind to a target component of a biochemical system or modulate the activity of the target, and which is co-compartmentalised into the microcapsules.

Abstract: The invention describes a method for the synthesis of compounds comprising the steps of: (a) compartmentalising two or more sets of primary compounds into microcapsules; such that a proportion of the microcapsules contains two or more compounds; and (b) forming secondary compounds in the microcapsules by chemical reactions between primary compounds from different sets; wherein one or both of steps (a) and (b) is performed under microfluidic control; preferably electronic microfluidic control The invention further allows for the identification of compounds which bind to a target component of a biochemical system or modulate the activity of the target, and which is co-compartmentalised into the microcapsules.

Abstract: The invention describes a method for isolating one or more genetic elements encoding a gene product having a desired activity, comprising the steps of: (a) compartmentalising genetic elements into microcapsules; and (b) sorting the genetic elements which express the gene product having the desired activity; wherein at least one step is under microfluidic control. The invention enables the in vitro evolution of nucleic acids and proteins by repeated mutagenesis and iterative applications of the method of the invention.