Techniques, systems, and devices are disclosed for non-thermal cycling of polymerase chain reaction (PCR). In one aspect, a method for cycling PCR includes receiving an electrolytic fluid including ions, primers, polymerase enzymes, nucleotides, and a double-stranded nucleic acid in a fluid chamber having a first electrode and a second electrode, applying an electric field across the first and the second electrodes to generate a first pH level of the electrolytic fluid to denature the double-stranded nucleic acid to at least partial single strands, and applying a second electric field across the first and second electrodes to produce a second pH level of the electrolytic fluid, in which the second pH level enables binding of a polymerase enzyme and a primer with a corresponding segment of the single strands.

A microfluidic device (10) comprising: a main body; at least one source reservoir and at least one collection reservoir (18,20); at least one fluid channel (12) for channelling a fluid comprising a compound from the at least one source reservoir (18) to the at least one collection reservoir (20); a plurality of chambers (13) for holding cells, wherein the plurality of chambers (13) are formed underneath and open to the fluid channel (12), wherein a fluid flow is generated through the at least one fluid channel (12) by a difference in hydrostatic pressure between fluid in the at least one source reservoir (18) and fluid the at least one collection reservoir (20) such that the fluid flow provides a compound concentration gradient across the plurality of chambers (13) and wherein the at least one collection reservoir (20) has an overflow opening (32) to substantially maintain a level of hydrostatic pressure in the at least one collection reservoir (20).

Extracting and concentrating particles from a first fluid sample includes: providing the first fluid sample to a fluid exchange module of a microfluidic device, providing a second fluid sample to the fluid exchange module, in which the first fluid sample and the second fluid sample are provided under conditions such that particle-free portions of the first fluid sample are shifted, and an inertial lift force causes the particles in the first fluid sample to cross streamlines and transfer into the second fluid sample; passing the second fluid sample containing the transferred particles to a particle concentration module under conditions such that particle-free portions of the second fluid sample are shifted, and such that the particles within the second fluid sample are focused to a streamline within the particle concentration module.

Methods and apparatus for driving flow in a microfluidic arrangement are provided. In one disclosed arrangement, the microfluidic arrangement comprises a first liquid held predominantly by surface tension in a shape defining a microfluidic pattern on a surface of a substrate. The microfluidic pattern comprises at least an elongate conduit and a first reservoir. The area of contact between the substrate and a portion of the first liquid that forms the elongate conduit defines a conduit footprint. The area of contact between the substrate and a portion of the first liquid that forms the first reservoir defines a first reservoir footprint. The size and shape of each of the conduit footprint and the first reservoir footprint are such that a maximum Laplace pressure supportable by the first liquid in the elongate conduit without any change in the conduit footprint is higher than a maximum Laplace pressure supportable by the first liquid in the first reservoir without any change in the first reservoir footprint. A delivery member having an internal lumen leading to a distal opening through which liquid can be delivered is provided. Liquid is pumped into the microfluidic pattern through the distal opening while the distal opening is held in a delivery position. The delivery position is such that the liquid enters the microfluidic pattern via the elongate conduit and drives a flow of liquid into the first reservoir.

In one embodiment, a selective plane illumination microscopy system for capturing light emitted by an illuminated specimen, the system including a specimen support having a top surface configured to support a specimen holder and an opening configured to provide access to a bottom of the specimen holder, and a selective plane illumination microscopy optical system positioned beneath the specimen support, the optical system configured to illuminate the specimen with a sheet of excitation light and including an excitation objective, a detection objective, and an open-top, hollow imaging element that is configured to contain a liquid, wherein the imaging element is positioned within the opening of the specimen support and optical axes of the objectives are aligned with the imaging element such that the axes pass through the imaging element and intersect at a position near the top surface of the specimen support.

Extracting and concentrating particles from a first fluid sample includes: providing the first fluid sample to a fluid exchange module of a microfluidic device, providing a second fluid sample to the fluid exchange module, in which the first fluid sample and the second fluid sample are provided under conditions such that particle-free portions of the first fluid sample are shifted, and an inertial lift force causes the particles in the first fluid sample to cross streamlines and transfer into the second fluid sample; passing the second fluid sample containing the transferred particles to a particle concentration module under conditions such that particle-free portions of the second fluid sample are shifted, and such that the particles within the second fluid sample are focused to a streamline within the particle concentration module.

A fluidic manifold cartridge includes a plurality of source fluid inlets and fluid outlets. A plurality of fluid input flow channels are provided. Each fluid inlet is in fluid communication with a fluid input flow channel. Each fluid input flow channel directs fluid from the fluid inlet past a plurality of valves. A plurality of fluid output flow channels are in fluid communication with a fluid outlets. Each valve includes a valve seat, a portion of membrane, and a control fluid opening. Each valve has an open and closed condition. The valve in the open condition directs fluid from a fluid input flow channel to a fluid output flow channel. The control fluid opening directs control fluid to move the membrane so as to change the valve between the open and closed conditions. Systems and methods for fluidic manifold are also disclosed.

A centrifugal separating assembly for separating a fluid biological product into discrete components by centrifugation is disclosed. The assembly includes a first container defining a first cavity adapted to receive a human biological product, the first container having a circular upper wall, a cylindrical sidewall, and a concave shaped bottom wall. The assembly further includes a second container defining a second cavity adapted to receive discrete components. The first container is positioned within the second container, and moveable to a selected position within the second container so that a layer of a fluid biological product will be at a desired location after centrifugation.

Provided herein are compositions, systems, and methods for high throughput screening. In particular, provided herein are microfluidic devices for high throughput analysis of multiplex chemical (e.g., drug interactions) across a wide range of concentrations.

Provided is an apparatus (100) for transporting sweat droplets (112) to a sensor. The apparatus comprises a chamber (102) for filling with sweat. The chamber has an inlet (104) lying adjacent the surface of the skin (106), which inlet permits sweat to enter and fill the chamber. The chamber has an outlet (114) from which a sweat droplet protrudes once the chamber has been filled. The apparatus further comprises a fluid transport assembly which is designed to enable the sweat droplet protruding from the outlet to become detached from the outlet of the chamber. The sweat droplet is subsequently transported by the fluid transport assembly to the sensor. Once the protruding droplet has been released from the outlet, the outlet is made available for a subsequent sweat droplet to protrude therefrom upon further filling of the chamber. The released sweat droplet is transported via the fluid transport assembly at least as fast as the subsequent sweat droplet protrudes from the outlet such that the respective sweat droplets do not contact each other before reaching the sensor. Thus, the apparatus supplies sweat to the sensor in a dropwise manner. Further provided is a system comprising the apparatus and a sensor, and a method for transporting sweat droplets to a sensor.