A microfluidic device includes: a first microfluidic channel; a second microfluidic channel extending along the first microfluidic channel; and a first array of islands separating the first microfluidic channel from the second microfluidic channel, in which each island is separated from an adjacent island in the array by an opening that fluidly couples the first microfluidic channel to the second microfluidic channel, in which the first microfluidic channel, the second microfluidic channel, and the islands are arranged so that a fluidic resistance of the first microfluidic channel increases relative to a fluidic resistance of the second microfluidic channel along a longitudinal direction of the first microfluidic channel such that, during use of the microfluidic device, a portion of a fluid sample flowing through the first microfluidic channel passes through one or more of the openings between adjacent islands into the second microfluidic channel.

An apparatus for calibrating a flux analyzer comprises a first frame; a second frame; and a permeable membrane. The first frame and the second frame are connected or integrally formed. A method for calibrating a flux analyzer is provided which uses an artificial standard rather than a biological standard.

A system for passive permeation of a biological material is disclosed. The system may include a main channel extending between an upper portion and a lower portion; a main reservoir connected to the upper portion of the main channel and in fluid communication with the main channel; a bottom reservoir connected to the lower portion of the main channel and in fluid communication with the main channel; at least one secondary channel disposed in at least one position between the upper portion and the lower portion of the main channel such that fluid communication is established in the at least one position between the at least one secondary channel and the main channel; and at least one secondary reservoir respectively connected to an upper portion of each of the at least one secondary channel and in fluid communication with the respective at least one secondary channel.

A microfluidic device includes a particle sorting region having a first, second and third microfluidic channels, a first array of islands separating the first microfluidic channel from the second microfluidic channel, and a second array of islands separating the first microfluidic channel from the third microfluidic channel, in which the island arrays and the microfluidic channels are arranged so that a first fluid is extracted from the first microfluidic channel into the second microfluidic channel and a second fluid is extracted from the third microfluidic channel into the first microfluidic channel, and so that particles are transferred from the first fluid sample into the second fluid sample within the first microfluidic channel.

A method of creating a reperfusion injury can include: providing a cell culture device having an internal chamber with at least one port coupled to a perfusion modulating system capable of modulating perfusion in the internal chamber, wherein the internal chamber includes a cell culture; perfusing a fluid through the internal chamber with the perfusion modulating system, wherein the perfusion modulating system includes at least one pump; reducing fluid flow through the internal chamber; reperfusing fluid flow through the internal chamber; and creating a reperfusion injury in the cell culture by the reperfusion of the fluid flow through the internal chamber. The cell culture includes at least one type of tissue cell. The cell culture can include a tissue construct formed of hydrogel and/or extracellular matrix.

Disclosed is a method and apparatus for manipulating fluids. The apparatus may include a microfluidic structure including inlet channels (1 and 2) and outlet channels (306, 307, 308, 309, 310, 311, 312, 313, and 314) oriented among bifurcated (5), trifurcated (6) and merging junctions (7 and 8). The apparatus splits and merges fluids flowing in the channels to produce successive dilutions of the fluids within the outlet channels. Multiple apparatus may be combined in serial, parallel, combined serial and parallel and/or stacked configurations. One or more apparatus may be used alone or to provide various devices or chambers with the diluted fluids.

The present invention contemplates compositions, devices and methods of simulating biological fluids in a fluidic device, including but not limited to a microfluidic chip. In one embodiment, fluid comprising a colloid under flow in a microfluidic chip has a fluid density or viscosity similar to a bodily fluid, e.g. blood, lymph, lung fluid, or the like. In one embodiment, a fluid is provided as a Theologically biomimetic blood surrogate or substitute for simulating physiological shear stress and cell dynamics in fluidic device, including but not limited to immune cells.

An in vitro microfluidic intestine on-chip is described herein that mimics the structure and at least one function of specific areas of the gastrointestinal system in vivo. In particular, a multicellular, layered, microfluidic intestinal cell culture, which is some embodiments is derived from patient's enteroids-derived cells, is described comprising L cells, allowing for interactions between L cells and gastrointestinal epithelial cells, endothelial cells and immune cells. This in vitro microfluidic system can be used for modeling inflammatory gastrointestinal autoimmune tissue, e.g., diabetes, obesity, intestinal insufficiency and other inflammatory gastrointestinal disorders. These multicellular-layered microfluidic intestine on-chips further allow for comparisons between types of gastrointestinal tissues, e.g., small intestinal duodenum, small intestinal jejunum, small intestinal ileum, large intestinal colon, etc., and between disease states of gastrointestinal tissue, i.e. healthy, pre-disease and diseased areas. Additionally, these microfluidic gut-on-chips allow identification of cells and cellular derived factors driving disease states and drug testing for reducing inflammation.

Devices are for assessing the migration response in the presence of a stable encapsulated gradient of a factor or factor combination, and quantifying the adherence response inside micro-channels in the presence of different factors. A platform is for obtaining information relating to migration score or the quantification of adhered cells through use of the devices, and it allows this information to be used to assess therapeutic potential. A method quantifies the cells migration response and the cell adherence response.

Described herein are an adaptable apparatus and methods for detecting the presence of a target substance in a liquid. For example, the adaptable apparatus can be a medallion that detects illicit drugs in a beverage. The adaptable apparatus comprises a detection unit comprising an indicator that is configured to display a signal upon the detection of an interaction with the target substance. In some examples, the adaptable apparatus can be attached to an implement.