Abstract: Microfluidic devices and methods for focusing components in a fluid sample are described herein. The microfluidic devices feature a microfluidic chip having a micro-channel having a constricting portion that narrows in width, and a flow focusing region downstream of the micro-channel. The flow focusing region includes a positively sloping bottom surface that reduces a height of the flow focusing region and sidewalls that taper to reduce a width of the flow focusing region, thereby geometrically constricting the flow focusing region. The devices and methods can be utilized in sex-sorting of sperm cells to improve performance and increase eligibility.

Abstract: Microfluidic devices and methods for focusing components in a fluid sample are described herein. The microfluidic devices feature a microfluidic chip having a micro-channel having a constricting portion that narrows in width, and a flow focusing region downstream of the micro-channel. The flow focusing region includes a positively sloping bottom surface that reduces a height of the flow focusing region and sidewalls that taper to reduce a width of the flow focusing region, thereby geometrically constricting the flow focusing region. The devices and methods can be utilized in sex-sorting of sperm cells to improve performance and increase eligibility.

Abstract: A passive, hydrodynamic technique implemented using a microfluidic device to perform co-encapsulation of samples in droplets and sorting of said droplets is described herein. The hydrodynamic technique utilizes laminar flows and high shear liquid-liquid interfaces at a microfluidic junction to encapsulate samples in the droplets. A sorting mechanism is implemented to separate sample droplets from empty droplets. This technique can achieve a one-one-one encapsulation efficiency of about 80% and can significantly improve the droplet sequencing and related applications in single cell genomics and proteomics.

Abstract: A microfluidic system configured to focus particles suspended in a fluid. One general aspect includes a microfluidic system comprising one or more substrates and a focusing channel formed in the one or more substrates and spanning a length from an inlet to an outlet for receiving a flow of particles suspended in fluid, wherein the particles have a diameter (a) and the focusing channel has a hydraulic diameter (dh).

Abstract: A microfluidic system configured to focus particles suspended in a fluid. One general aspect includes a microfluidic system comprising one or more substrates and a focusing channel formed in the one or more substrates and spanning a length from an inlet to an outlet for receiving a flow of particles suspended in fluid, wherein the particles have a diameter (a) and the focusing channel has a hydraulic diameter (dh).

Abstract: Microfluidic devices and methods for focusing components in a fluid sample are described herein. The microfluidic devices feature a microfluidic chip having a micro-channel having a constricting portion that narrows in width, and a flow focusing region downstream of the micro-channel. The flow focusing region includes a positively sloping bottom surface that reduces a height of the flow focusing region and sidewalls that taper to reduce a width of the flow focusing region, thereby geometrically constricting the flow focusing region. The devices and methods can be utilized in sex-sorting of sperm cells to improve performance and increase eligibility.

Abstract: Microfluidic devices and methods for focusing components in a fluid sample are described herein. The microfluidic device has at least one flow focusing channel where the components are focused or re-oriented by the geometry of the channel. From an upstream end of the flow focusing channel to a downstream end of the flow focusing channel, at least a portion of the flow focusing channel has a reduction in height and at least a portion of the flow focusing channel narrows in width, thereby geometrically constricting the flow focusing channel. The devices and methods can be utilized in sex-sorting of sperm cells to improve performance and increase eligibility.

Abstract: An interfacial technique utilizes hydrodynamic micro-vortices to perform (i) high efficiency single cell encapsulation and (ii) size-selective capturing of cells based on their sizes in a single microfluidic device. A notable feature of this technique is that it can perform high efficiency single cell encapsulation at low cell concentrations, and this technique is all passive, controlled only by the flow rates of the two phases and does not require complex structures or on-chip active devices. Single bead/cell encapsulation was demonstrated at 50% efficiency, which is at least 10 times greater than the random encapsulations at the introduced cell concentrations. Also demonstrated is the selective trapping of cells based on their sizes. This present technique expands the capabilities of droplet microfluidics for applications ranging from single cell genomics, proteomic assays to sample preparation.

Abstract: A passive, hydrodynamic technique implemented using a microfluidic device to perform co-encapsulation of samples in droplets and sorting of said droplets is described herein. The hydrodynamic technique utilizes laminar flows and high shear liquid-liquid interfaces at a microfluidic junction to encapsulate samples in the droplets. A sorting mechanism is implemented to separate sample droplets from empty droplets. This technique can achieve a one-one-one encapsulation efficiency of about 80% and can significantly improve the droplet sequencing and related applications in single cell genomics and proteomics.

Abstract: Microfluidic devices and methods for focusing components in a fluid sample are described herein. The microfluidic device has at least one flow focusing channel where the components are focused or re-oriented by the geometry of the channel. From an upstream end of the flow focusing channel to a downstream end of the flow focusing channel, at least a portion of the flow focusing channel has a reduction in height and at least a portion of the flow focusing channel narrows in width, thereby geometrically constricting the flow focusing channel. The devices and methods can be utilized in sex-sorting of sperm cells to improve performance and increase eligibility.

Abstract: A microfluidic system configured to focus particles suspended in a fluid. One general aspect includes a microfluidic system comprising one or more substrates and a focusing channel formed in the one or more substrates and spanning a length from an inlet to an outlet for receiving a flow of particles suspended in fluid, wherein the particles have a diameter (a) and the focusing channel has a hydraulic diameter (dh).

Abstract: An interfacial technique utilizes hydrodynamic micro-vortices to perform (i) high efficiency single cell encapsulation and (ii) size-selective capturing of cells based on their sizes in a single microfluidic device. A notable feature of this technique is that it can perform high efficiency single cell encapsulation at low cell concentrations, and this technique is all passive, controlled only by the flow rates of the two phases and does not require complex structures or on-chip active devices. Single bead/cell encapsulation was demonstrated at 50% efficiency, which is at least 10 times greater than the random encapsulations at the introduced cell concentrations. Also demonstrated is the selective trapping of cells based on their sizes. This present technique expands the capabilities of droplet microfluidics for applications ranging from single cell genomics, proteomic assays to sample preparation.

Abstract: In a method of moving droplets, local heat is applied to a surface portion of a droplet for an amount of time sufficient to create a Marangoni flow in the droplet. Droplets are suspended in an emulsion in a carrier liquid on a substrate. A laser beam is used to move one of the droplets. the droplet consists of a first substance and a carrier liquid consists of a second substance that is not mixable with the first substance. The droplet is placed in the carrier liquid, and the mixture is emulsified. The emulsified mixture is placed on a substrate. Then the local heat is applied to the surface of the droplet. The first substance may include oil and the second substance may include water.

Abstract: In a method of moving droplets, local heat is applied to a surface portion of a droplet for an amount of time sufficient to create a Marangoni flow in the droplet. Droplets are suspended in an emulsion in a carrier liquid on a substrate. A laser beam is used to move one of the droplets. the droplet consists of a first substance and a carrier liquid consists of a second substance that is not mixable with the first substance. The droplet is placed in the carrier liquid, and the mixture is emulsified. The emulsified mixture is placed on a substrate. Then the local heat is applied to the surface of the droplet. The first substance may include oil and the second substance may include water.