Abstract: A microfluidic device includes a device body defining a microfluidic pathway including a first channel, a second channel downstream of the first channel, and a junction including a transition between the first channel and the second channel. The transition is configured to inhibit fluid entering the transition from the first channel from forming a meniscus across the second channel, thereby inhibiting capillary-driven flow into the second channel. The microfluidic device further includes a valve that, when activated while capillary-driven flow of the fluid is inhibited at the transition, induces capillary-driven flow through the second channel by facilitating formation of the meniscus.

Abstract: An assay device includes a colorimetric testing assembly including a detection area, a fluid inlet, and a microfluidic network including a first path extending to the detection area and a second path extending to the detection area. When a fluid (e.g., a buffer fluid or a combined buffer and sample solution) is provided to the fluid inlet, a first portion of the fluid rehydrates a first dried reagent (e.g., a dried enzyme label) disposed along the first path to produce a first rehydrated reagent and a second portion of the fluid rehydrates a second dried reagent (e.g., a dried substrate) to produce a second rehydrated reagent. The first rehydrated reagent and the second rehydrated reagent are then sequentially delivered to the detection area by capillary-driven flow to perform the assay.

Abstract: An assay device includes an electrochemical testing assembly having a test channel including a capture reagent selected to capture a target analyte and an electrode having a surface in communication with the test channel. The assay device further includes a microfluidic network in communication with the test channel, a buffer fluid inlet in communication with the microfluidic network, and a detection reagent disposed within the microfluidic network. When a buffer fluid is provided to the buffer fluid inlet, the buffer fluid transports the detection reagent to the test channel by capillary-driven flow, and wherein the electrode is configured to measure an electrical response indicating capture of the target analyte by the capture reagent after transportation of the detection reagent to the test channel.

Abstract: The present disclosure provides potentiometric ion selective electrodes, methods for preparing the potentiometric ion selective electrode, a microfluidic electrode array comprising the potentiometric ion selective electrodes, and methods of using the microfluidic electrode array to measure inorganic cations and inorganic anions in a solution.

Abstract: The invention discloses a method and a system to detect a target nucleic acid sequence in a sample using padlock probe-based rolling circle amplification and nuclease protection. Padlock probe-based rolling circle amplification and nuclease protection may be used in combination with other detection assays to detect target nucleic acid sequences in a sample.

Abstract: The present invention relates generally to an assay for detecting and differentiating single or multiple analytes, if present, in a fluid sample, including devices and methods of use of the same.

Abstract: A system for and methods of analyzing a test sample through the use of a rotary apparatus that includes a microfluidic paper-based apparatus (mPAD). The apparatus includes two or more layers that are rotatable with respect to one another. A middle layer may comprise a microfluidic apparatus having one or more reagent channels. Each of the reagent channels may include reagent dried on the surface of the channel, and, together with an absorption pad, may be aligned vertically with a sample chamber. Male and female engagement surfaces on each of the middle layer, the top layer, and the bottom layer interlock to secure each layers in vertical alignment so that fluid flows through the apparatus to contact a test sample with a reagent and facilitate detection of a target analyte in the test sample in the sample chamber.

Abstract: A new solvent-based method is presented for making low-cost composite graphite electrodes containing a thermoplastic binder. The electrodes, termed thermoplastic electrodes (TPEs), are easy to fabricate and pattern, give excellent electrochemical performance, and have high conductivity (1500 S m?1). The thermoplastic binder enables the electrodes to be hot embossed, molded, templated, and/or cut with a CO2 laser into a variety of intricate patterns. These electrodes show a marked improvement in peak current, peak separation, and resistance to charge transfer over traditional carbon electrodes. The impact of electrode composition, surface treatment (sanding, polishing, plasma treatment), and graphite source were found to impact fabrication, patterning, conductivity, and electrochemical performance. Under optimized conditions, electrodes generated responses similar to more expensive and difficult to fabricate graphene and highly oriented pyrolytic graphite electrodes.

Abstract: A new solvent-based method is presented for making low-cost composite graphite electrodes containing a thermoplastic binder. The electrodes, termed thermoplastic electrodes (TPEs), are easy to fabricate and pattern, give excellent electrochemical performance, and have high conductivity (1500 S m?1). The thermoplastic binder enables the electrodes to be hot embossed, molded, templated, and/or cut with a CO2 laser into a variety of intricate patterns. These electrodes show a marked improvement in peak current, peak separation, and resistance to charge transfer over traditional carbon electrodes. The impact of electrode composition, surface treatment (sanding, polishing, plasma treatment), and graphite source were found to impact fabrication, patterning, conductivity, and electrochemical performance. Under optimized conditions, electrodes generated responses similar to more expensive and difficult to fabricate graphene and highly oriented pyrolytic graphite electrodes.

Abstract: A new solvent-based method is presented for making low-cost composite graphite electrodes containing a thermoplastic binder. The electrodes, termed thermoplastic electrodes (TPEs), are easy to fabricate and pattern, give excellent electrochemical performance, and have high conductivity (1500 S m?1). The thermoplastic binder enables the electrodes to be hot embossed, molded, templated, and/or cut with a CO2 laser into a variety of intricate patterns. These electrodes show a marked improvement in peak current, peak separation, and resistance to charge transfer over traditional carbon electrodes. The impact of electrode composition, surface treatment (sanding, polishing, plasma treatment), and graphite source were found to impact fabrication, patterning, conductivity, and electrochemical performance. Under optimized conditions, electrodes generated responses similar to more expensive and difficult to fabricate graphene and highly oriented pyrolytic graphite electrodes.

Abstract: Antimicrobial resistance (AMR), the ability of a bacterial species to resist the action of an antimicrobial drug, has been on the rise due to the widespread use of antimicrobial agents, and one of the many ways AMR can spread is through contaminated water sources. To monitor these water sources, we have developed an inexpensive, fast assay using a paper-based analytical device (PAD) that can test for the presence of ?-lactamase-mediated resistance as one major form of AMR that has reliably detected resistance in sewage water.

Abstract: A system for and methods of analyzing a test sample through the use of a rotary apparatus that includes a microfluidic paper-based apparatus (mPAD). The apparatus includes two or more layers that are rotatable with respect to one another. A middle layer may comprise a microfluidic apparatus having one or more reagent channels. Each of the reagent channels may include reagent dried on the surface of the channel, and, together with an adsorption pad, may be aligned vertically with a sample chamber. Male and female engagement surfaces on each of the middle layer, the top layer, and the bottom layer interlock to secure each layers in vertical alignment so that fluid flows through the apparatus to contact a test sample with a reagent and facilitate detection of a target analyte in the test sample in the sample chamber.

Abstract: A new solvent-based method is presented for making low-cost composite graphite electrodes containing a thermoplastic binder. The electrodes, termed thermoplastic electrodes (TPEs), are easy to fabricate and pattern, give excellent electrochemical performance, and have high conductivity (1500 S m?1). The thermoplastic binder enables the electrodes to be hot embossed, molded, templated, and/or cut with a CO2 laser into a variety of intricate patterns. These electrodes show a marked improvement in peak current, peak separation, and resistance to charge transfer over traditional carbon electrodes. The impact of electrode composition, surface treatment (sanding, polishing, plasma treatment), and graphite source were found to impact fabrication, patterning, conductivity, and electrochemical performance. Under optimized conditions, electrodes generated responses similar to more expensive and difficult to fabricate graphene and highly oriented pyrolytic graphite electrodes.

Abstract: Example devices and methods of tongue stimulation for communication of information to a user are disclosed herein. In an example, a tongue stimulation device may include a body configured to be placed entirely within a mouth of the user and atop the tongue of the user. An array of electro-tactile elements may be distributed on the body, wherein each of the electro-tactile elements is configured to stimulate an area of the tongue adjacent the electro-tactile element. A wireless receiver coupled to the body may be configured to receive stimulation information wirelessly from outside the mouth of the user. At least one processing unit coupled to the body may be configured to transform the received stimulation information into a stimulation signal for each of the electro-tactile elements, and to provide the stimulation signals to the electro-tactile elements.

Abstract: Example devices and methods of tongue stimulation for communication of information to a user are disclosed herein. In an example, a tongue stimulation device may include a body configured to be placed entirely within a mouth of the user and atop the tongue of the user. An array of electro-tactile elements may be distributed on the body, wherein each of the electro-tactile elements is configured to stimulate an area of the tongue adjacent the electro-tactile element. A wireless receiver coupled to the body may be configured to receive stimulation information wirelessly from outside the mouth of the user. At least one processing unit coupled to the body may be configured to transform the received stimulation information into a stimulation signal for each of the electro-tactile elements, and to provide the stimulation signals to the electro-tactile elements.

Abstract: Apparatus for quantitative analytical measurements using capillarity-based analytical devices is described. Porous cellulose (i.e., common filter paper) may be used as the reagent carrier for the analyses. Hydrophobic materials may be printed onto the paper to generate paths that restrict liquid flow by capillary action to defined regions. At least one colorimetric reagents effective for reacting with a specific analyte is deposited along a capillary flow path generated in the device. Upon placing the liquid containing the analyte on one end of the path, the liquid moves along the circuit by capillary action, and the flowing analyte reacts with reagent generating color along the flow path until all of the analyte is consumed. Analyte quantification is achieved by measuring the length of the colored portion along a flow path employing a direct-reading measurement scale.

Abstract: The present disclosure provides a method to allow a user to pre-screen numerous crystallization conditions in the crystallization space to identify those conditions with the highest probability of yielding crystals and high quality diffracting crystals. In one embodiment, the dilute solution thermodynamic virial coefficient, termed B, is used to aid in the determination crystallization conditions that increase the probability of producing crystals for the crystallant of interest. The present disclosure also provide methods for predicting solution conditions that generate beneficial solubility and/or stability conditions for a polypeptide of interest using the B parameter. Devices for use in the described methods are also described.

Abstract: The present invention provides a microchip for performing electrophoresis with pulsed amperometric detection (PAD) for the separation and detection of underivatized carbohydrates, amino acids, sulfur-containing antibiotics, etc. PAD allows for the direct detection of amines, thiols, alcohols and carbohydrates and therefore is a useful technique for the development of electrochemical detection for microchip electrophoresis.

Abstract: A kit for the rapid detection of pathogens in food supplies. The kit includes a microspot device and one or more indicator reagents to be applied to a well of the microspot device. The employed indicator reagent produces a detectable change upon contact with a pathogen of interest. The microspot device is fabricated from a porous membrane, such as filter paper. A substantially continuous boundary composed of a low melting temperature solid is deposited within the porous membrane extending from the top of the membrane to the bottom of the membrane and defines the peripheral sides of the well. Additionally, a barrier is applied to the bottom of the membrane, thus defining the bottom of the well. The kit can further include growth media for enriching the pathogenic bacteria and instructions for use of the kit employing the microspot device and the one or more indicator reagents.

Abstract: The present disclosure provides a method to allow a user to pre-screen numerous crystallization conditions in the crystallization space to identify those conditions with the highest probability of yielding crystals and high quality diffracting crystals. In one embodiment, the dilute solution thermodynamic virial coefficient, termed B, is used to aid in the determination crystallization conditions that increase the probability of producing crystals for the crystallant of interest. The present disclosure also provide methods for predicting solution conditions that generate beneficial solubility and/or stability conditions for a polypeptide of interest using the B parameter. Devices for use in the described methods are also described.