Abstract: Sub-micrometer bioparticles are separated by size in a microfluidic channel utilizing a ratchet migration mechanism. A structure within the microfluidic channel includes an array of micro-posts arranged in laterally shifted rows. Reservoirs are disposed at each end of the microfluidic channel. A biased AC potential is applied across the channel via electrodes immersed into fluid in each of the reservoirs to induce a non-uniform electric field through the microfluidic channel. The applied potential comprises a first waveform with a first frequency that induces electro-kinetic flow of sub-micrometer bioparticles in the microfluidic channel, and an intermittent superimposed second waveform with a higher frequency. The second waveform selectively induces a dielectrophoretic trapping force to selectively impart ratchet migration based on particle size for separating the sub-micrometer bioparticles by size in the microfluidic channel.

Abstract: The field of this invention relates to immunohistochemistry (IHC) and in situ hybridization (ISH) for the targeted detection and mapping of biomolecules (e.g., proteins and miRNAs) in tissues or cells for example, for research use and for clinical use such by pathologists (e.g., biomarker analyses of a resected tumor or tumor biopsy). In particular, the use of mass spectrometric imaging (MSI) as a mode to detect and map the biomolecules in tissues or cells for example. More specifically, the field of this invention relates to photocleavable mass-tag reagents which are attached to probes such as antibodies and nucleic acids and used to achieve multiplex immunohistochemistry and in situ hybridization, with MSI as the mode of detection/readout. Probe types other than antibodies and nucleic acids are also covered in the field of invention, including but not limited to carbohydrate-binding proteins (e.g., lectins), receptors and ligands.

Abstract: Synthetic human cell mimic hydrogel particles and their use in cytometric or coulter device applications are described. The synthetic human cell mimic hydrogel particles described herein are selectively tunable to have at least one optical, volumetric, or capacitance property that is substantially similar to a corresponding optical, volumetric, or capacitance property of the human cell mimic hydrogel particle's natural biological cell counterpart.

Abstract: A hydrogen-bonded organic framework nanosheet, a preparation method and application thereof are provided. The preparation method includes in a small heat-resistant glass container, mixing 1,2,4,5-tetrakis (4-carboxyphenyl) benzene (H4TCPB) with N,N-dimethylformamide (DMF), heating until the solid is dissolved, placing the uncapped small glass container in a large heat-resistant glass container filled with some water, sealing the large glass container, standing and heating the large glass container in a constant-temperature oven to obtain colorless crystals, suction filtering to obtain a solid material, drying, grinding, and then dispersing the solid material in a solvent, performing ultrasonication in an ice-water bath, centrifuging to discard supernatant, and drying to obtain the hydrogen-bonded organic framework nanosheets.

Abstract: Method and device (1b) for performing the optical analysis of particles (2) contained in suspension in a fluid (3) arranged inside a microfluidic device (4) which maintains it at a temperature significantly lower than the ambient temperature; the formation of humidity on the outer surface (8) of the cover of the microfluidic device is avoided by applying a thermal flow (P) which determines an increase in the temperature of the outer surface (8) of the cover to above the condensation temperature (Td), or reduction in the ambient temperature (and/or humidity) in the vicinity of the cover (8), so as to bring the condensation temperature (Td) (dew point) to below the temperature of the surface (8) of the cover determined by the internal operating temperature.

Abstract: The present invention relates to a system for predicting gestational diabetes mellitus (GDM) of pregnant individuals, wherein the system comprises an operation module, and the operation model comprises a support vector regression model, and the system is used to predict the plasma glucose levels at 1 hour and/or 2 hours of oral glucose tolerance test (OGTT) by using a support vector regression developed prediction model generated by substituting the concentration of the biomarkers in fasting blood samples of pregnant individuals. The present invention provides biomarkers and biomarker-based diagnostic models for differential diagnosis of gestational diabetes mellitus (GDM), which can be applied to diagnosis or prediction of GDM in early stage and are of great significance to the prevention or treatment of GDM.

Abstract: A sampling device is provided for concentrating a liquid specimen sample. The sampling device includes a filtration assembly and a filter-collection receptacle disengageably coupled to the filtration assembly. The filtration assembly includes a tubular container and a plunger, which is insertable into the tubular container via a proximal container opening. The filtration assembly is configured such that movement of the plunger within the tubular container, when a liquid specimen sample is contained in the tubular container and a filter is disposed in the tubular container, pushes at least a portion of the liquid specimen sample through the filter. The sampling device is configured such that the filter is advanceable into the filter-collection receptacle while the filter-collection receptacle is disengageably coupled to the filtration assembly. Other embodiments are also described.

Abstract: Methods and devices for pretreatment of a conducting sampling substrate which enable an electrostatic charge to be used to transfer analyte molecules onto a sampling substrate, where the analyte molecules are in powder or particulate form. In an embodiment of the present invention, the electrostatic charge can be used to transfer powder samples containing nitrogenous bases, nucleosides, food additives, and prescription drugs such as acetaminophen, oxycodone, and dextromethorphan. In an embodiment of the present invention, a powder sample is transferred to a pre-treated sampling substrate using an electrostatic charge. The spatial distribution of the powder on the original surface is retained on the pre-treated sampling substrate using the electrostatic charge transfer. The electrostatic charge transfer can be used to transfer powder samples present on a surface or in the chambers of 96, 384 and 1536 well plate formats to either pins or mesh and analyzed with ambient desorption ionization.

Abstract: Methods for isolating proteins from a honey sample are provided. The methods include contacting the honey sample with a substrate functionalized with one or more reactive dyes and recovering proteins associated with the substrate. Methods for detecting proteins in a honey sample and assessing the risk of colony collapse disorder are also provided.

Abstract: Glycans having a branched structure are labeled with a labeling agent, such as 2-aminobenzoic acid, having one site that is easily negatively charged. At this time, reduction which is usually performed in labeling by reduction amination is not performed. A sample for mass spectrometry containing the labeled form of glycans thus obtained is prepared, and is subjected to MS/MS analysis in negative ion mode. In the MS/MS spectra obtained by the MS/MS analysis, peaks of E ions, D ions and the like which reflect the branched structure clearly appear. As a result, structural analysis of an entirety of the glycan including the branched structure can be easily performed.

Abstract: The disclosure features methods of identifying specific drug candidates for disease treatment, the methods including: for pairs of associated expressed proteins in a protein-protein interaction network for a plurality of biological samples, comparing relative concentration values of the associated proteins in each of the biological samples to identify outliers among a distribution of the relative concentration values, identifying a set of proteins involved in dysregulated protein-protein interactions in the network based on the outliers, and predicting an efficacy of one or more drug candidates from among a set of drug candidates for treating a disease based on the identified set of proteins and information about one or more of proteins, protein complexes, biological pathways, and functional modules targeted by the set of drug candidates.

Abstract: An in-line holographic microscope can be used to analyze on a frame-by-frame basis a video stream to track individual colloidal particles' three-dimensional motions. The system and method can provide real time nanometer resolution, and simultaneously measure particle sizes and refractive indexes. Through a combination of applying a combination of Lorenz-Mie analysis with selected hardware and software methods, this analysis can be carried out in near real time. An efficient particle identification methodology automates initial position estimation with sufficient accuracy to enable unattended holographic tracking and characterization.

Abstract: Methods are described for detecting or determining the amount of antidepressants and/or antidepressant metabolites in a sample. More specifically, mass spectrometric methods are described for detecting and quantifying antidepressants and/or antidepressant metabolites in a sample.

Abstract: Calibrants and methods of making the same include using mixtures of multifunctional core compounds or multifunctional dendrimers that are functionalized to yield a set of discrete compounds which cover a range of collisional cross sections (CCSs) for calibrating ion mobility and variation in molecular weight to calibrate the mass to charge (m/z) measurements of mass spectrometry, as well as for calibrating tandem instruments that measure both dimensions. Methods of using the calibrants are also disclosed, such as in mass spectrometry.

Abstract: In a screening kit and a confirmed and typing diagnosis system for primary aldosteronism, a sample is pretreated by a magnetic bead bonded with a balanced hydrophilic-lipophilic polymer on the surface thereof, and process conditions are optimized and the content of each the five markers such as, aldosterone in the sample is accurately detected by liquid chromatography-tandem mass spectrometry for one time, thus finding the optimal screening cut-off value of 20.4; when a positive result is judged, PA is confirmed and subjected to typing diagnosis according to the test values of the markers, thereby achieving the simultaneous detection of the content of each the five markers such as, aldosterone on the same platform. Therefore, the screening kit and confirmed and typing diagnosis system for primary aldosteronism are integrated with screening, confirmed and typing diagnosis functions, thus providing a reliable laboratory examination basis for clinicians to formulate an effective therapeutic regimen.

Abstract: Various aspects of the present disclosure are directed toward methods and apparatuses for interacting a first liquid and a second liquid in one or more fluidic channels of a capillary structure. The methods and apparatuses can include providing at least one capillary barrier that positions a meniscus of the first liquid at a fluid-interface region using capillary forces within the capillary structure. Additionally, a path is provided along one of the channels for the second liquid to flow toward the fluid-interface region. Additionally, gas pressure is released, via a gas-outflow port, from the fluid-interface region while flow of the first liquid is arrested. Further, the first liquid and the second liquid contact in the fluid-interface region with the capillary barrier holding the first liquid at the fluid-interface region.

Abstract: The present invention provides methods for improved label-free absolute quantification of relatively low abundant polypeptides by liquid chromatography/mass spectrometry analysis of peptide products obtained from simple or complex polypeptide mixtures. The methods for absolute quantification include MS signals from a set of qualified ions of peptide products of a relatively high abundant polypeptide to improve quantification of a relatively low abundant polypeptide.

Abstract: Fluorescent water soluble conjugated polymers including polycyclic aromatic comonomers are provided. The conjugated polymers can be linked to an acceptor fluorescent dye. The conjugated polymers find use in conjugates with biological substrates having applications in a variety of applications including methods of analyte detection.

Abstract: Peptide and/or protein quantitation methods, kits, and compositions, particularly useful for mass spectrometry, are provided herein based on a bathocuproine-based composition complex such as bathocuproinedisulfonic acid disodium salt hydrate complex. The methods are one-step rapid absorbance methods using small sample volumes. They produce a robust signal with high signal to background ratio and accurately quantitate even complex peptide mixtures with low variability and high sensitivity.

Abstract: Apparatus and methods are described including placing a sample into a sample carrier that comprises a plurality of regions having upper and lower surfaces, having respective heights that are different from each other, and being configured such that cells form a monolayer, the monolayer within respective regions of the sample carrier having respective, different densities from each other, due to the respective regions of the sample carrier having respective heights that are different from each other. Microscopic images are acquired of each of the plurality of regions. Measurements are performed upon cell types that have a relatively high density upon microscopic images of a region of the sample chamber having a relatively low height, and measurements are performed upon cell types that have a relatively low density upon microscopic images of a region of the sample chamber having a relatively great height. Other applications are also described.