Provided are nanoporous silicon nitride membranes and methods of making such membranes. The membranes can be part of a monolithic structure or free-standing. The membranes can be made by transfer of the nanoporous structure of a nanoporous silicon or silicon oxide film by, for example, reactive ion etching. The membranes can be used in, for example, filtration applications, hemodialysis applications, hemodialysis devices, laboratory separation devices, multi-well cell culture devices, electronic biosensors, optical biosensors, active pre-concentration filters for microfluidic devices.

A microfluidic device is provided. A manifold having a first channel, a second channel, and a third channel configured to transport blood can be coupled to a substrate defining an artificial vasculature. The first channel can be configured to carry blood in a first direction. Each of the second and third channels can couple to the first channel at a first junction and can be configured to receive blood from the first channel. The second channel can be configured to carry blood in a second direction away from the first direction. The third channel can be configured to carry blood in a third direction away from the second direction. The first, second, and third channels can be non-coplanar.

Many hand-held diagnostics are limited in their functionality due to the challenging physics associated with small dimensional systems. An example of this is capillary forces in hydrophilic systems, such as the tight retention of liquid passing through a small pore filtration membrane, or capillary force driven microfluidics where, to keep liquid flowing the dimensions of the system become so small that the flow rates are too low to be useful, or the manufacturing of such devices becomes uneconomical. This disclosure details methods to ‘reset’ the capillary force condition to avoid the requirement of transient pressure spikes associated with the breakthrough pressure of small pore membranes, and avoid the necessity of extremely small microfluidic channels, which can be useful in applications such as filtration of whole blood to plasma using only suction pressure or passive capillary pressure.

A porous membrane for use in an electroosmotic pump for pumping a fluid by electroosmotic transport, the porous membrane comprising: first and second opposite surfaces and a net fluid flow direction extending in the porous membrane between said opposite surfaces, wherein when a given amount of charge flows through the porous membrane from the first to the second opposite surface more electroosmotic transport of the fluid will occur than when the same amount of charge flows through the porous membrane from the second to the first, opposite surface.

Various aspects of the present disclosure are directed toward apparatus and methods method for filtering water fluid by screening ionic minerals including sodium chloride from the water fluid. In one embodiment, the water fluid is passed into a work zone defined at least in part by oppositely-arranged first and second porous structures, each of which have a plurality of gated channels. The water fluid is processed in the work zone by applying respective electric voltages to electrically bias the first porous structure and the second porous structure. The respective electric voltages deplete sodium chloride ions in the water fluid in the work zone due to ion-flux continuity. In response to processing of the water fluid, ion-filtered water is collected from the work zone.

Polymer hydrogels and methods for selective retrieval of microbial targets from microwells and other cell culture devices. The methods use semi-permeable, photodegradable hydrogel membranes that permit exchange of nutrients and waste products but seals motile bacteria and other microbes within microwells. Light exposure can be used to degrade the hydrogel membrane in a targeted manner and release the microbes from targeted microwells for further study.

The presently disclosed subject matter provides a microfluidic device that can simulate capillary blood flow on a fetal side of the device and pooled blood on a maternal side of the device (i.e., intervillous space). The microfluidic device can reconstitute the maternal-fetal interface, can expand the capabilities of cell culture models, and can provide an alternative to current maternal-fetal transfer models.

Devices, methods, and kits directed towards collecting and preparing cells using a separable sample collection layer may be configured to collect or treat cells from a liquid sample with mechanisms for easy transfer of the cells prior to analysis or imaging. The separable sample collection layer may comprise a porous membrane that cells may be collected on, and one or more support layers comprising tape with one or more adhesive coatings and release liner. The devices, methods and kits may be configured with support layers comprising cutouts that form vertically or horizontally oriented microchannels for efficiently removing undesirable liquid. Following collection and/or treatment, cells collected onto the porous membrane may be adhered to another surface for further processing or analysis.

Fluidic devices and related methods are generally provided. The fluidic devices described herein may be useful, for example, for diagnostic purposes (e.g., detection of the presence of one or more disease causing bacteria in a patient sample). Unlike certain existing fluidic devices for diagnostic purposes, the fluidic devices and methods described herein may be useful for detecting the presence of numerous disease causing bacteria in a patient sample substantially simultaneously (e.g., in parallel). In some embodiments, the fluidic devices and methods described herein provide highly sensitive detection of microbes in relatively large fluidic samples (e.g., between 0.5 mL and about 5 mL), as compared to certain existing fluidic detection (e.g., microfluidic) devices and methods. In an exemplary embodiment, increased detection sensitivity of microbial pathogens present in a patient sample (e.g., blood) is performed by selectively removing human nucleic acid prior to sensitive detection of microbial infection. In some embodiments, the fluidic device allows for the identification of microbial pathogens directly from unprocessed blood without having to conduct blood culturing processes.

A technology that provides various modular biomimetic microfluidic modules emulating varieties of microvasculature in body. These microfluidic-base capillaries and lymphatic Technology modules are constructed as multilayered-microfluidic microchannels of various shapes, and aspect ratios using diverse biocompatible microfluidic polymers. Then, various semipermeable membranes are sandwiched in between these multilayered microfluidic microchannels. These membranes have different chemical, physical characteristics and MWCO values. Consequently, this design will produce much smaller dimension channels similar to human vasculature to achieve biomimetic properties like of human organs and tissues. By interchanging microfluidic-layers or the membranes various diverse modules are designed that act as building blocks for constructing various medical devices, various forms of dialysis devices including albumin and lipid dialysis, water purification, bioreactors, bio-artificial organ support systems. Connecting various modules in diverse combinations, permutations, in parallel and/or in series to ultimately design many unrelated medical devices such as dialysis, bioreactors and organ support devices.