Abstract: Microfluidic devices fabricated from paper that has been covalently modified to increase its hydrophobicity, as well as methods of making and using thereof are provided herein. The devices are typically small, portable, flexible, and both easy and inexpensive to fabricate. Microfluidic devices contain a network of microfluidic components, including microfluidic channels, microfluidic chambers, microwells, or combinations thereof, designed to carry, store, mix, react, and/or analyze liquid samples. The microfluidic channels may be open channels, closed channels, or combinations thereof. The microfluidic devices may be used to detect and/or quantify an analyte, such as a small molecules, proteins, lipids polysaccharides, nucleic acids, prokaryotic cells, eukaryotic cells, particles, viruses, metal ions, and combinations thereof.

Abstract: Self-regulating pressure source. The pressure source includes a chamber enclosing a chemical monopropellant. A moveable boss is attached to a deformable membrane sealing an air chamber, the moveable boss and air chamber being disposed within the chamber. A catalyst is disposed around the membrane so as to be covered by the boss in a retracted position so that the monopropellant is broken down by the catalyst to produce a gas. The gas pressure will increase within the chamber causing air in the air chamber to compress thereby to pull the boss into the retracted position to cover the catalyst thereby to regulate the pressure within the chamber. The self-regulating pressure source is particularly suited to power fluidic elastomeric actuators.

Abstract: Described herein are assays for determining total suspended solids (TSS) in liquids. Here TSS can be determined by flowing turbid liquid samples in a porous medium. Using such an assay, TSS can be determined with small volumes of liquid and in short times without the need for dedicated optics and instruments. The assays can be used to determine total suspended solids in any liquid medium, for example, the assay can be used in an immunoprecipitin assay to determine the amount of antigen or antibody present in blood or other fluid.

Abstract: In one aspect, methods of patterning of thin films of an ionotropic polymer (e.g., poly(acrylic acid)) are provided. These processes can create micron or sub-micron-scale patterns of ionotropic polymers such as cation crosslinked poly(acrylic acid) (CCL-PAA). In one embodiment, patterning may be performed within microfluidic channels by flowing a solution of crosslinking agent (e.g., metal cations such as Ag+, Ca2+, Pd2+, Al3+, La3+, and Ti4+) that can crosslink a portion of an ionotropic polymer in contact with the solution. In another embodiment, methods of patterning ionotropic polymers involve photolithography. Upon patterning a positive photoresist (e.g., diazonaphthoquinone-novolac resin) on a film of CCL-PAA, the exposed regions of CCL-PAA can be etched by an aqueous solution. Advantageously, the patterned, crosslinked polymer may also serve as both a reactant and a matrix for subsequent chemistry.

Abstract: A surgical device for displacement of organs within a body cavity for providing at least visual access to a selected site includes an expandable bladder, wherein the elasticity of the bladder varies across the surface of the bladder, said variation in elasticity selected to provide a predetermined, non-spherical shape when expanded; and a valve on the proximal end on the inflatable bladder for introduction of a pressurizing gas into the soft bladder.

Abstract: A microfluidic method and device for focusing and/or forming discontinuous sections of similar or dissimilar size in a fluid is provided. The device can be fabricated simply from readily-available, inexpensive material using simple techniques.

Abstract: A microfluidic valve assembly includes a structure defining a microfluidic fluid path and an actuator that can be moved between different positions controlling flow through the channel. In one embodiment, the actuator can be threaded into at least a portion of the structure, and can be moved rotationally between a first position, causing relatively greater constriction of a microfluidic fluid path, and a second position causing relatively lesser constriction of the fluid path. Actuating the actuator, e.g., by rotation, can deform material between the valve and the fluid path, thereby constricting at least a portion of the underlying fluid path and regulating the flow of a fluid in the fluid path. In another aspect, the invention provides a reservoir into which fluid can be placed and from which fluid can be introduced into a microfluidic system. In one embodiment, the reservoir is expandable and thereby able to store fluid under pressure for delivery to a microfluidic system.

Abstract: Soft pneumatic actuators based on composites consisting of elastomers with embedded sheet or fiber structures (e.g., paper or fabric) that are flexible but not extensible are described. On pneumatic inflation, these actuators move anisotropically, based on the motions accessible by their composite structures. They are inexpensive, simple to fabricate, light in weight, and easy to actuate. This class of structure is versatile: the same principles of design lead to actuators that respond to pressurization with a wide range of motions (bending, extension, contraction, twisting, and others). Paper, when used to introduce anisotropy into elastomers, can be readily folded into three-dimensional structures following the principles of origami; these folded structures increase the stiffness and anisotropy of the elastomeric actuators, while keeping them light in weight.

Abstract: Paper-based microfluidic systems and methods of making the same are described.

Abstract: A device and methods for detecting the effect of compounds on an organism are provided. Furthermore, the device and methods disclosed herein allow for the fractionation of complex samples and the isolation of one or more organisms for the samples. The device and methods also allow for the study of development of the organism.

Abstract: Some embodiments of the disclosed subject matter includes a laminated robotic actuator. The laminated robotic actuator includes a strain-limiting layer comprising a flexible, non-extensible material in the form of a sheet or thin film, a flexible inflatable layer in the form of a thin film or sheet in facing relationship with the strain-limiting layer, wherein the inflatable layer is selectively adhered to the strain-limiting layer, and wherein a portion of an un-adhered region between the strain-limiting layer and the inflatable layer defines a pressurizable channel, and at least one fluid inlet in fluid communication with the pressurizable channel. The first flexible non-extensible material has a stiffness that is greater than the stiffness of the second flexible elastomeric material and the flexible elastomer is non-extensible under actuation conditions.

Abstract: The disclosure provides low cost, portable three-dimensional devices for performing multiplexed assays. The devices comprise at least two substantially planar layers disposed in parallel planes, wherein one of the layers is movable relative to each other parallel to the planes to permit the establishment of fluid flow communication serially between the two layers.

Abstract: Embodiments of the invention provide lateral flow and flow-through bioassay devices based on patterned porous media, methods of making same, and methods of using same. Under one aspect, an assay device includes a porous, hydrophilic medium; a fluid impervious barrier comprising polymerized photoresist, the barrier substantially permeating the thickness of the porous, hydrophilic medium and defining a boundary of an assay region within the porous, hydrophilic medium; and an assay reagent in the assay region.

Abstract: Manipulation of flames is described using electric fields. In those instances in which electric fields are used, the electric fields may be time-varying gradient electric fields, and in some instances may be oscillating electric fields. The manipulation may include extinction, suppression, control of mixing of the flame, concentration, and/or bending, among other types.

Abstract: Systems and methods for providing a soft robot is provided. In one system, a robotic device includes a flexible body having a fluid chamber, where a portion of the flexible body includes an elastically extensible material and a portion of the flexible body is strain limiting relative to the elastically extensible material. The robotic device can further include a pressurizing inlet in fluid communication with the fluid chamber, and a pressurizing device in fluid communication with the pressurizing inlet, the pressurizing device including a reaction chamber configured to accommodate a gas-producing chemical reaction for providing pressurized gas to the pressurizing inlet.

Abstract: The present invention relates to methods, compositions and kits related to a novel in vitro assay for a high-capacity and high-throughput method for measuring the ability of cancer cells to migrate in a three-dimensional cellular assay. The three-dimensional cellular invasion assay provides a method for determining and quantitating the metastatic potential and invasive capacity of a cancer cell. Other aspects of the invention further relate to the use of the in vitro assay to screen for agents and compounds capable of inhibiting intravasation, and thereby modulating the metastatic potential of cancer cells. The methods, compositions and three-dimensional assay provide a highly sensitive assay system capable of mimicking the in vivo cellular and molecular interactions required for successful completion of intravasation.

Abstract: The multiplexed electrochemical microfluidic paper-based analytical device comprises multiple detection zones for the detection of multiple biochemical analytes from one single sample. Cavity valves integrated on the device will deliver the sample to different detection zones. These analytes include, but are not limited to, urea, creatinine, creatine, glucose, lactate, ethanol, uric acid, cholesterol, pyruvate, creatinine, ?-hydroxybutyrate, alanine aminotrasferase, aspartate aminotransferase, alkaline phosphatase, and acetylcholinesterase (or its inhibitors). This system will provide a simple and low-cost POC approach to obtain quantitative and multiple biological information from one sample (e.g. one drop of blood).

Abstract: An assay method is described, which comprises the steps of immobilizing a binding partner (e.g., an antigen or antibody) for an analyte to be detected (e.g., an antibody or antigen) on a portion of a surface of a microfluidic chamber; passing a fluid sample over the surface and allowing the analyte to bind to the binding partner; allowing a metal colloid, e.g., a gold-conjugated antibody, to associate with the bound analyte; flowing a metal solution, e.g., a silver solution, over the surface such as to form an opaque metallic layer; and detecting the presence of said metallic layer, e.g., by visual inspection or by measuring light transmission through the layer, conductivity or resistance of the layer, or metal concentration in the metal solution after flowing the metal solution over the surface.

Abstract: A soft robotic device includes a flexible body having a width, a length and a thickness, wherein the thickness is at least 1 mm, the flexible body having at least one channel disposed within the flexible body, the channel defined by upper, lower and side walls, wherein at least one wall is strain limiting; and a pressurizing inlet in fluid communication with the at least one channel, the at least one channel positioned and arranged such that the wall opposite the strain limiting wall preferentially expands when the soft robotic device is pressurized through the inlet.

Abstract: A method and apparatus for delivering one or more fluids. Fluids may be delivered sequentially from a common vessel to a chemical, biological or biochemical process.