A target analyte is extracted out of a sample fluid in a sample fluid passage by diffusing the target analyte through a supported liquid membrane to a product fluid passage. Extraction of the target analyte is accelerated by applying an electric field across and perpendicular to the supported liquid membrane with electrodes. Passage of selected ions across an exchange membrane extending between one of the electrodes and the supported liquid membrane is inhibited.

A method for analyzing a sample includes introducing the sample into a vessel including a cation-exchange resin, where the cation-exchange resin has a high affinity to one or more interferent species in the sample, directing the sample through the cation-exchange resin to thereby capture one or more interference species in the cation-exchange resin to purify the sample, and releasing the purified sample from the vessel. Additionally, a method for analyzing a sample includes receiving an image depicting a diagnostic test region and a color reference chart, converting a test region image portion of the image to an analytical color space, determining first and second coordinate values characterizing the test region image portion in the analytical color space, and providing a quantitative measurement of an analyte of interest in the sample based on the first and/or second coordinate values and a predictive formula based on the color reference chart.

Disclosed are methods, compositions, and devices for an integrated, heterogeneous ion-exchange membrane-based plastic microfluidic biochip platform that can be used to detect multiple diagnostic markers present in real samples. Its various components can be easily integrated in a modular fashion for different applications. Automated control allows sequential and dynamic activation of different components on the chip. The integrated platform consists of three units and is designed to execute the following functions: (i) separation of the target biomolecules from the real sample, (ii) localizing and concentrating the targeted molecules at a specific location in the microfluidic chip, and (iii) detection of the targeted molecules using hybridization/docking events against a complementary ssDNA oligoprobe sequence or a specific antibody.

Exosomes carry microRNA biomarkers, occur in higher abundance in cancerous patients than in healthy ones, and because they are present in most biofluids, including blood and urine, can be obtained non-invasively. Standard laboratory techniques to isolate exosomes are expensive, time-consuming, provide poor purity, and recover on the order of 25% of the available exosomes. We present a new microfluidic technique to simultaneously isolate exosomes and preconcentrate them by electrophoresis using a high transverse local electric field generated by ion-depleting ion-selective membrane. We use pressure-driven flow to deliver an exosome sample to a microfluidic chip such that the transverse electric field forces them out of the cross flow and into an agarose gel which filters out unwanted cellular debris while the ion-selective membrane concentrates the exosomes through an enrichment effect. We efficiently isolated exosomes from 1×PBS buffer, cell culture media and blood serum. Using flow rates from 150 μL/hr to 200 μL/hr and field strengths of 100 V/cm, we consistently captured between 60% to 80% of exosomes from buffer, cell culture media, and blood serum as confirmed by both fluorescence spectroscopy and nanoparticle tracking analysis. Our microfluidic chip maintained this recovery rate for more than twenty minutes with a concentration factor of 15 for ten minutes of isolation.

A rapid detection method of a target biomolecule comprising an antigenic moiety is provided. The method includes providing a source biological sample comprising the target biomolecule; contacting the source biological sample to an ion-exchange medium; eluting the captured-target biomolecule from the ion-exchange medium as an eluate, and loading the eluate to a rapid diagnostic testing device comprising an antibody. The eluate comprises a concentrated form of the biomolecule in a solution having a salt concentration greater than 150 mM. A concentration of the target biomolecule in the eluate is in a range from about 2 to 25 compared to a concentration of the biomolecule in the source biological sample. The target biomolecule binds to the antibody under the salt concentration of greater than 150 mM. A device for rapid detection of target biomolecule is also provided.

Systems and methods are described to concentrate a remote sample for analysis. A sample concentration system embodiment includes, but is not limited to, a plurality of valves including at least a first valve, a second valve, and a third valve; a plurality of columns including at least a first column and a second column, the first column fluidically coupled to the first valve, the second column fluidically coupled to the second valve; and a flow meter coupled with the third valve, the flow meter fluidically coupled with each of the first column and the second column when the plurality of valves is in a first flow path configuration to measure an amount of the liquid sample passed through the first column and the second column, wherein the plurality of valves includes a second flow path configuration and a third flow path configuration.

The analyzing method for quantifying urea in a sample solution includes: a pretreatment step of pretreating the sample solution with at least one of a membrane device including a reverse osmosis membrane and an ion exchange device including an ion exchanger; and an analyzing step of analyzing a target substance in the pretreated sample solution. The analyzing step is based on, for example, flow injection analysis (FIA), and includes a step of quantifying the target substance by measuring the absorbance of a liquid containing a substance generated by reacting the target substance with a reagent.

Disclosed herein is a preprocessing apparatus that makes it possible to highly efficiently analyze specimens held by solid media, such as dried blood spots to be used for newborn mass screening or the like. The preprocessing apparatus includes: a preprocessing container setting part in which a preprocessing container containing a solid sample including a specimen to be analyzed and a solid medium holding the specimen is to be set; a carrying mechanism that carries the preprocessing container set in the preprocessing container setting part; and a preprocessing part that has a port for setting the preprocessing container carried by the carrying mechanism and that is configured to perform preprocessing including extraction processing for extracting the specimen from the solid sample contained in the preprocessing container set in the port.

An amphoteric dissociation ion exchange separation medium, the surface of which is an amphoteric dissociationcovalently-modified layer. When an environmental pH value is lower than the isoelectric point, pIm, of the covalently-modified layer, the type of net charges on the surface of the covalently-modified layer is positive and the separation medium has the properties of an anion exchanger; when the environmental pH value is higher than the pIm, the type of net charges on the covalently-modified layer surface is negative and the separation medium has the properties of acation exchanger. The separation medium has the properties of an anion exchanger and a cation exchanger at both sides of the pIm, respectively. The pH of an eluent can be adjusted to allow the separation medium surface and the target substance to have the same type of net charges, so that the target substance can be released by electrostatic repulsion.

A rapid detection method of a target biomolecule comprising an antigenic moiety is provided. The method includes providing a source biological sample comprising the target biomolecule; contacting the source biological sample to an ion-exchange medium; eluting the captured-target biomolecule from the ion-exchange medium as an eluate, and loading the eluate to a rapid diagnostic testing device comprising an antibody. The eluate comprises a concentrated form of the biomolecule in a solution having a salt concentration greater than 150 mM. A concentration of the target biomolecule in the eluate is in a range from about 2 to 25 compared to a concentration of the biomolecule in the source biological sample. The target biomolecule binds to the antibody under the salt concentration of greater than 150 mM. A device for rapid detection of target biomolecule is also provided.