Abstract: Disclosed is a sample analyzer including: a transport apparatus configured to transport a sample rack holding a sample container; and a measurement apparatus body configured to measure a sample in the sample container held in the sample rack transported by the transport apparatus, wherein the transport apparatus includes a light source holding unit configured to detachably hold a light source unit, and the measurement apparatus body includes a detection unit configured to detect, via an analysis specimen containing the sample, light emitted from the light source unit held in the light source holding unit.

Abstract: A sample testing system includes a test receptacle support structure, an optical element positioned for transmitting electromagnetic radiation emitted or reflected by a sample disposed in a test receptacle supported by the test receptacle support structure, a cleaning member, and an automated transport arm configured to (i) detachably couple the cleaning member, (ii) move the detachably-coupled cleaning member into a position proximate to and/or contacting the optical element, and (iii) decouple the cleaning member.

Abstract: The present invention relates to portable devices for point-of-care diagnostics that can perform measurements on a sample (e.g., blood, serum, saliva, or urine) and relay data to an external device for, e.g., data analysis. The device can comprise a paper-based diagnostic substrate and a base substrate that include electronic circuitry and electronic elements necessary for performing the measurements. The device can also comprise an antenna for near field communication with an external device. Another aspect of the invention relates to methods of using these devices.

Abstract: A spectroscopic sensor device comprising an absorption path for receiving at least one fluid medium that is to be analyzed, an infrared radiation source for sending out infrared radiation into the absorption path, an infrared sensor array that has a multiplicity of pixels that can be individually evaluated, which are fashioned to detect the infrared radiation propagated from the infrared radiation source through the fluid medium as individual pixel measurement signals, and comprising an evaluation device that is fashioned to combine a multiplicity of pixel measurement signals of the pixels and to output them via an individual measurement channel. Furthermore, a method for operating a spectroscopic sensor device is also described.

Abstract: A method for detecting and quantifying fibrosis, which involves at least; positioning a non-colored fixed tissue sample on a support; carrying out infrared acquisition, by scanning, of points of the sample; converting the infrared spectrum produced by each acquired point into at least one spectral image; carrying out a digital processing operation on the spectral image by distinguishing between at least physiological collagen and pathological collagen from fibrosis, attributing, to each point, a spectral class defined by an algorithm classifying the spectra according to the spectral similarities % thereof, then attributing a status to each class by statistically comparing with a digital model of spectra; quantifying the relative surface area occupied by the points of each status; and recording the result.

Abstract: An optoelectronic sensor (10) for detecting objects in a monitored zone (20) is provided which has the following: a front screen (38); a light transmitter (12) for transmitting a light beam (16); a movable deflection unit (18) for the periodic sampling of the monitored zone (20) by the light beam (16); a light receiver (26) for generating a received signal from the light beam (22) remitted by the objects; at least one test light transmitter (42); at least one test light transmitter (42), at least one test light receiver (44) and at least one test light reflector (48) which span a test light path (46a-b) through the front screen (38); and an evaluation unit (32) which is configured to acquire pieces of information on the objects in the monitored zone (20) from the received signal and to recognize an impaired light permeability of the front screen (38) from a test light signal which the test light receiver (44) generates from test light which is transmitted from the test light transmitter (42) and which is refl

Abstract: Systems and methods for generating a three-dimensional gas map includes a remote vehicle including reflective material. A positioning stage including multidimensional movement to track the remote vehicle. A light head to reflect light off of the remote vehicle. A controller to analyze received light to determine gas content and generate a three-dimensional gas map.

Abstract: An apparatus for detecting a presence of a predetermined material within a sample uses signal generation circuitry for generating a first signal having a first distinct signature including a first eccentricity of a mode intensity, a first shift in a center of the mode intensity and a first rotation of an ellipsoidal intensity output of the mode intensity and applying the first signal to the sample. A detector receives the first signal after the first signal passes through the sample and detects a second distinct signature including a second eccentricity of the mode intensity, a second shift in the center of the mode intensity and a second rotation of the ellipsoidal intensity output of the mode intensity. The detector also determines the presence of the predetermined material within the sample based on the detected second distinct signature within the first signal received from the sample and provides an output of an indication of the presence of the predetermined material responsive to the determination.

Abstract: An apparatus for recognizing a position of a crystal in a nuclear detector, including: a silicon semiconductor detector array arranged in a crystal array in the nuclear detector, where each row/or column of silicon semiconductor detectors is configured to output a sum of voltages outputted by the silicon semiconductor detectors in the row/or column at a row/or column signal output end; row signal comparing modules, one to one correspondingly connected to each row signal output end and configured to obtain a row comparison result for each row of silicon semiconductor detectors; column signal comparing modules, one to one correspondingly connected to each column signal output end and configured to obtain a column comparison result for each column of silicon semiconductor detectors; and a crystal position recognizing module configured to recognize a position of a crystal hit by a photon according to each row comparison result and each column comparison result.

Abstract: Fluorescing compositions are disclosed for monitoring cleaning of a surface. The fluorescing compositions are stable, fluoresce under UV light, and do not leave a mark after drying and removal. The compositions include an optical brightener solubilized with cyclodextrin.

Abstract: A wavelength scanning apparatus that detects at least four different fluorescent emission wavelengths simultaneously or nearly simultaneously is described. The wavelength scanning apparatus includes a heating block having at least four sample wells, each sample well configured for receiving a sample, at least four excitation activation apertures, and at least four fluorescence emission discharge apertures. The wavelength scanning apparatus also includes an analysis scanner having at least four light sources, where the at least four light sources excite at least four fluorophores, at least four excitation light filters that filter out light except that of the desired excitation wavelength/s, at least four fluorescence emission light filters that filter out light except that of the desired fluorescent emission wavelengths, and at least four photodetectors to detect light of the desired fluorescent emission wavelengths.

Abstract: In the present invention, a fluorescent substance detection system (S) for detecting fluorescent substances in any environment is provided. Said detection system (S) comprises at least one illumination unit (1) which emits light to said environment in order to excite said substances; detection units (2), at least at a number equal to the number of types of fluorescent substances, for detecting emissions coming from said excited fluorescent substances and bandpass filters (3), each connected to detection units (2) one by one, wherein bandpass filters (3) have a center wavelength matched to the center emission wavelength of corresponding fluorescent substance.

Abstract: Provided herein is an apparatus, including a photon emitter configured to emit photons onto a surface of an article, a photon detector array configured to receive photons from surface features of the article; and a processing means configured for processing photon-detector-array signals corresponding to photons scattered from the surface features and photons fluoresced from the surface features, wherein the processing means is further configured for classifying the surface features of the article.

Abstract: Provided is a method for inhibiting self-absorption effect of a LIBS, comprising ablating a to-be-measured sample via a pulse laser thereby generating plasma, and selectively stimulating the plasma using a wavelength-tunable laser beam enabling transition of particles in a ground-state in the plasma to high energy state as stimulated absorption, thereby improving a stimulated absorption transition efficiency of the particles in a ground-state, and preventing plasma spectrum from being influenced by self-absorption effect. The invention is capable of eliminating the self-absorption effect without introducing external interference, obtaining original characteristics of emission spectrum from the center of the plasma, and essentially inhibiting and finally eliminating the self-absorption effect of laser plasma by making use of intrinsic physical property of plasma.

Abstract: A method is disclosed of measuring the thickness of a thin coating on a substrate comprising dissolving the coating and substrate in a reagent and using the post-dissolution concentration of the coating in the reagent to calculate an effective thickness of the coating. The preferred method includes measuring non-conducting films on flexible and rough substrates, but other kinds of thin films can be measure by matching a reliable film-substrate dissolution technique. One preferred method includes determining the thickness of Boron Carbide films deposited on copper foil. The preferred method uses a standard technique known as inductively coupled plasma optical emission spectroscopy (ICPOES) to measure boron concentration in a liquid sample prepared by dissolving boron carbide films and the Copper substrates, preferably using a chemical etch known as ceric ammonium nitrate (CAN). Measured boron concentration values can then be calculated.

Abstract: A device for sustaining a plasma in a torch is provided. In certain examples, the device comprises a first electrode configured to couple to a power source and constructed and arranged to provide a loop current along a radial plane of the torch. In some examples, the radial plane of the torch is substantially perpendicular to a longitudinal axis of the torch.

Abstract: The present invention relates to detection systems and methods that detect fluorescence, luminescence, chemiluminescence or phosphorescence signatures in the form of an electrical signal conducted and emitted from metallic containing surfaces. Thus, the present invention provides for detecting fluorescence digitally and directly without the need for expensive detectors.

Abstract: A system and method for the detection of one or more analytes in a collected sample employs capillary action in a sample card containing a sample substrate, at least one test capsule and an absorbent pad. The absorbent pad absorbs the contents of the test capsule and delivers the same to the sample substrate, with the contents of the test capsule chemically reacting with at least one detection reagent to establish an optical indicator for the analyte(s). The sample card can be automatically tested within a reader device, which records and processes an optical signal produced by the chemical reaction and outputs a test result. The collected sample can then be further analyzed using a second device. Additionally, an adhesive component can be provided so that a sample can be collected thereon. Furthermore, the at least one detection reagent can include a surfactant.

Abstract: A system for physiologic parameter examination includes a housing and a test-strip tray. The housing includes a carrying cavity disposed on a top surface of the housing and including a window. The carrying cavity is configured to receive a portable electronic device having an image-capturing component. The image-capturing component corresponds to the window. The test-strip tray is movably disposed in the housing and located below the carrying cavity. The test-strip tray is configured to carry at least one test strip. The image-capturing component is adapted to capture a test reaction of the test strip through the window. A method for test strip recognition and interpretation applicable to the system is also provided.

Abstract: A panel inspection apparatus is provided. The panel inspection apparatus has a support platform, a delivery platform and a panel inspection assembly. The delivery platform is disposed on the support platform, and the delivery platform has a push module for delivering the panel. The panel inspection assembly includes a plurality of light source modules and a plurality of image-taking modules corresponding to the light source modules. The light source modules include a front light source, a first horizontal light source, and a back light source. The image-taking modules include a front light image-taking module, a first horizontal light image-taking module, and a back light image-taking module. The push module delivers the panel across the support platform so that a plurality of light beams emitted from the light source modules can scan the panel to finish the panel inspection process.

Abstract: A method of determining a physical characteristic of an adhesive material on a semiconductor device element using structured light is provided. The method includes the steps of: (1) applying a structured light pattern to an adhesive material on a semiconductor device element; (2) creating an image of the structured light pattern using a camera; and (3) analyzing the image of the structured light pattern to determine a physical characteristic of the adhesive material. Additional methods and systems for determining physical characteristics of semiconductor devices and elements using structured light are also provided.

Abstract: The tunnel lining surface inspection system capable of measuring the three dimensional shape of the surface of the tunnel lining surface to precisely determine whether cracking has a risk of leading to flaking, by the light section method using the photography means and the slit laser beam projecting means, mounted in the vehicle, while the vehicle is traveling in the tunnel, and the vehicle used in the system are proposed. Image processing is performed to obtain the image used for inspecting the tunnel lining surface, by using the result of the three dimensional shape measurement of one side face of the tunnel lining surface, measured while the photography means/slit laser beam projecting means arrangement means is fixed to the first measurement position, and the result of the three dimensional shape measurement of the other side face of the tunnel lining surface, measured while the photography means/slit laser beam projecting means arrangement means is fixed to the second measurement position.

Abstract: A system that may include a radiation source to generate a beam of coherent radiation; traveling lens optics to focus the beam so as to generate multiple spots on a surface of a sample and to scan the spots together over the surface; collection optics to collect the radiation scattered from the multiple spots and to focus the collected radiation so as to generate a pattern of interference fringes; and a detection unit to detect changes in the pattern of interference fringes.

Abstract: A method of inspecting a component comprising a cellular structure bonded to a carrier substrate to form a matrix of open-ended cells is described. The method comprises: submerging the component in an inspection liquid disposed within a pressure vessel; changing the pressure within the pressure vessel; withdrawing the component from the inspection liquid; and determining whether the cells of the component are filled with the inspection liquid. A corresponding inspection apparatus is also described.

Abstract: A system for measuring a permittivity includes a resonant chamber, a conductive probe, a platform, a pillar, a detector, and a computing module. The resonant chamber has a cavity. The conductive probe is configured for introducing a microwave into the cavity of the resonant chamber. The platform is configured for carrying a sample. The pillar is positioned between the platform and a chamber wall, so that the platform protrudes from the chamber wall. The detector is used to detect a resonant frequency of the microwave when resonance occurs within the cavity. The computing module is configured for calculating a permittivity corresponding to the measured resonant frequency according to a corresponding relationship between resonant frequency and permittivity. The above-mentioned system for measuring a permittivity is capable of measuring a broader range of permittivity with simplified measurement steps and higher accuracy. A method for measuring a permittivity is also disclosed.

Abstract: Disclosed is an improved system and method to treat an edge of a material for determining a property of such material through measurements of electromagnetic waves. The system and method are operative to mitigate the adverse effects caused by the interaction between an electromagnetic wave and an edge of a sample of a material under test. The system and method define a configuration to block and significantly attenuate the propagation of electromagnetic waves that may reach an edge of the sample being evaluated. This configuration reduces the undesired effects caused by edge-diffraction that may interfere with the measurement of desired electromagnetic waves for material evaluation. As a result, a property of a material under test can be measured more accurately, especially near the edges of such material. In addition, the system and method enable the evaluation of a small-size sample of a material.

Abstract: According to the present disclosure, there is provided an x-ray imaging system, comprising: an x-ray source; an x-ray detector; a sample mount for mounting a sample in a beam path between the x-ray source and the x-ray detector; an enclosure enclosing at least the sample mount in an interior of the enclosure; and a climate control system for regulating the climate inside the enclosure, wherein: the enclosure has an aperture for enabling access to at least the sample mount from outside the enclosure; the enclosure is provided with a door operable between an open position in which the aperture is open and a closed position in which the aperture is closed by the door; and the climate control system is operable to provide a positive pressure differential between the interior of the enclosure and an exterior of the enclosure such that the interior of the enclosure is maintained at a higher pressure than the exterior of the enclosure when the door is open.

Abstract: An X-ray fluorescence analyzer includes: a sample stage; an X-ray source; a detector; an X stage; a Y stage; a ? stage; and a shielding container, wherein the irradiation position with primary X-rays is set at an offset position from a movement center of the X stage and the Y stage, wherein an irradiation area that is irradiatable with the primary X-rays is set to a selected segmented area from among segmented areas that are defined by segmenting the surface of the sample into four parts with a virtual segment lines in the X direction and the Y direction passing through the movement center, and wherein the ? stage is configured to switch the selected segmented area into any one of the segmented areas by rotating the sample stage by every 90 degrees.

Abstract: An X-ray fluorescence analyzer includes: a sample stage having a mounting surface on which a sample on which a sample is mounted is mounted; an X-ray source configured to irradiate the sample with primary X-rays and disposed immediately above an irradiation position of the sample; a detector configured to detect fluorescent X-rays emitted from the sample irradiated with the primary X-rays; and a shielding container configured to accommodate the sample stage, the X-ray source, and the detector and includes: a sample chamber configured to accommodate the sample stage; and a door provided at a top of the sample chamber and configured to open and close at least a front half of the sample chamber, wherein the X-ray source and the detector are disposed at a rear half of the sample chamber.

Abstract: Photothermal imaging systems and methods are disclosed that employ truncated-correlation photothermal coherence tomography (TC-PCT). According to the example methods disclosed herein, photothermal radiation is detected with an infrared camera while exciting a sample with the chirped delivery of incident laser pulses (where the pulses have a fixed width), and time-dependent photothermal signal data is obtained from the infrared camera and processed using a time-evolving filtering method employing cross-correlation truncation. The cross-correlation truncation method results in pulse-compression-linewidth-limited depth-resolved images with axial and lateral resolution well beyond the well-known thermal-diffusion-length-limited, depth-integrated nature of conventional thermographic and thermophotonic modalities.

Abstract: A method and a device for handling a closing element in a laboratory automation system are presented. The closing element is a sealing foil having at least two layers forming a first surface and an opposing second surface, respectively. The layers differ in at least one material property. The material property on at least one of the first surface and the second surface for identifying the orientation of the sealing foil is determined. A laboratory automation system for carrying out the method and/or with the device is also presented.

Abstract: Systems and methods for detecting a liquid. Detection a liquid may include detecting liquid at a boundary of an area and reporting the presence of the liquid. Reporting liquid at a boundary may prevent leaking of the liquid from the area. Detecting also includes detecting liquid inside the area. The amount of liquid detected inside the boundary may relate to a range of amounts of liquid. The minimum amount of the range may represent the minimum amount of liquid that is permissible in the area prior to taking action to deal with the liquid.

Abstract: Miniature resistive gas detectors incorporate thin films that can selectively identify specific gases when heated to certain characteristic temperatures. A solid state gas sensor module is disclosed that includes a gas sensor, a heater, and a temperature sensor, stacked over an insulating recess. The insulating recess is partially filled with a support material that provides structural integrity. The solid state gas sensor module can be integrated on top of an ASIC on a common substrate. With sufficient thermal insulation, such a gas detector can be provided as a low-power component of mobile electronic devices such as smart phones. A method of operating a multi-sensor array allows detection of relative concentrations of different gas species by either using dedicated sensors, or by thermally tuning the sensors to monitor different gas species.

Abstract: A measuring device for measuring a property of fuel supplied from a fuel tank to a combustion apparatus, may comprise a fuel pump that sucks the fuel in a fuel tank and pumps the fuel toward a combustion apparatus, a fuel discharging portion that discharges the fuel from the fuel pump into the fuel tank, a fuel-measuring storage chamber that receives the fuel discharged from the fuel discharging portion and a pair of electrodes disposed within the fuel-measuring storage chamber so as to measure capacitance.

Abstract: Provided are a hydrogen ion electrode composed of a composite material of polymer resin and nano iridium oxide, the composite material containing 1-10 nm sized nano iridium oxide particles and/or aggregates thereof which are dispersed to be electrically connected to each other in a moldable, thermoplastic, and hydrophobic polymer resin matrix; a pH sensor using the same; and a method for manufacturing the same. The surface of the hydrogen ion electrode shows very fast pH sensitivity when exposed to a sample solution, and the pH sensitivity is approximate to biphasic characteristics. Furthermore, regardless of high reproducibility of pH sensitivity, abrupt pH change, and repetitive use, very low hysteresis, durability due to high physical strength, and high surface regeneration due to polishing are exhibited, and thus, the lifetime of the electrode can be extended and various sizes and shapes of electrodes can be easily manufactured.

Abstract: The application relates to an electrode for use in the electrochemical detection of a target species, wherein the electrode has a planar surface disposed on which are probe molecules that are capable of binding selectively to the target species, wherein the electrode, prior to binding of the probe molecules with the target species, has an electron transfer resistance per area of the electrode of from 10 megaohms cm?2 to 95 megaohms cm?2.

Abstract: The invention provides electrochemical-based modules useful for the determination of an analyte in a bodily fluid sample. The modules of the invention provide opposed electrodes, but the contact areas for making electrical contact between the electrodes and the analyte measurement device are coplanar.

Abstract: Described herein are three-dimensional (3-D) paper fluidic devices. The entire 3-D device is fabricated on a support layer formed from a single sheet of material and assembled by folding the support layer. The folded structure may be enclosed in an impermeable cover or package. Chemically sensitive particles may be disposed in the support layer for use in detecting analytes.

Abstract: The disclosure relates to the use of nanoparticles that are coated with unique oligonucleotide (e.g., DNA) sequences of various base lengths (“nano-DNA”) that act as barcodes for product authentication, product serialization, brand protection, track-and-trace, intelligent supply chain, and law enforcement. The nano-DNA can be incorporated into inks, dyes, resins, labels, and other markings at all manufacturing levels, including the product (unit) level, to encode company and product-specific information. The nano-DNA can also be embedded in the product itself during the manufacturing process. Furthermore, the nano-DNA can be quickly, simply, and inexpensively monitored and verified using an electrochemical biosensor device in resource-limited field conditions.

Abstract: The claimed invention is directed to a finFET biosensor with improved sensitivity and selectivity. Embodiments of the invention are also directed to finFET biosensor arrays, methods for operating finFET biosensors with improved sensitivity and selectivity, and methods of operating finFET biosensor arrays.

Abstract: A bioFET cell for measuring a time dependent characteristic of an analyte bearing fluid includes a source, a drain, a semiconductive single wall carbon nanotube network layer extending between the source and drain electrodes and electrically coupled there between, a gate insulatively spaced from and disposed over and extending between the source and drain electrodes, a layer of at least one selected antibody disposed on and linked to the polymer layer to functionalize the semiconductive single wall carbon nanotube network layer to a selected target biomarker corresponding to the at least one selected antibody so that electron transport into the semiconductive single wall carbon nanotube network layer is facilitated, where the source, drain and gate electrodes with the carbon nanotube network layer form a defined channel through which the analyte bearing fluid may flow, and a high impedance source follower amplifier coupled to the source electrode.

Abstract: The present invention provides a structure for integrating microfluidic devices and electrical biosensors, including: a substrate for carrying an electrical biosensor; a microfluidic channel layer for providing at least a fluid to flow; a cover member for the inflow and outflow of the at least a fluid, and an electrical biosensor, having a biosensing layer and mounted to the cover member in a flip-chip manner; wherein the fluid flows into an inlet, passes the electrical biosensor for sensing and flows out through a fluid outlet.

Abstract: The present invention generally relates to devices and methods for containing molecules. In some embodiments, the device comprises a nanopore, a pore, and a cavity capable of entropically containing (e.g., trapping) a molecule (e.g., a biomolecule), e.g., for minutes, hours, or days. In certain embodiments, the method comprises urging a molecule into a cavity of a device by application of an electric field, and/or by deposition of fluids having different ionic strengths. The molecule may comprise, in some cases, nucleic acids (e.g., DNA). The molecule, when present in the cavity and/or the nanopore, may be capable of being analyzed, determined, or chemically modified. In some instances, a second molecule (e.g., a second molecule which interacts the first molecule) may also be urged into the cavity. In some embodiments, the interaction of the second molecule with the first molecule (e.g.

Abstract: In a linear drift tube partitioned into a plurality of cascaded drift tube segments each followed by an ion elimination region, a system and method of separating ions includes repeatedly establishing electric drift fields in the drift tube segments and in some of the ion elimination regions while establishing electric repulsive fields in others of the ion elimination regions such that ions having a predefined mobility or range of mobilities are transmitted through the drift tube in one direction, and when the ions reach the end of the drift tube the electric drift fields are reversed and the process is repeated to transmit the ions to the opposite end of the drift tube. Ions may be made to pass back and forth through the drift tube any number of times before being drawn out of the drift tube to an ion detector or into another drift tube.

Abstract: Apparatus is provided featuring an acoustic driver and a transducer. The acoustic driver is configured to provide an acoustic driver signal having a frequency that can be adjusted to yield a given wavelength, which in turn, will selectively capture a particular particle size of particles in a fluid, mixture or process flow. The transducer is configured to respond to the acoustic driver signal and provide an acoustic signal having a standing wave at the frequency in order to yield the given wavelength that will selectively capture the particular particle size of the particles in the fluid, mixture or process flow, in order to determine the mass of the particles having the particular particle size in the fluid, mixture or process flow.

Abstract: A device for inspection of a tubular piece includes a cart including plural elemental ultrasound transducers distributed along at least a first direction and a guide which cooperates with an exterior surface of the piece to position the cart such that the first direction essentially corresponds to a direction transverse to the tubular piece. A control electronics, connected to the electroacoustic transducers, includes a memory storing the timed excitation laws and a controller that applies in succession a respective timed excitation law to subsets of mutually adjacent elemental transducers along the first direction. The timed excitation laws are designed so that the elemental transducers of the respective subsets jointly produce incident beams of ultrasonic waves propagating along respective directions inclined relative to a direction normal to the exterior surface of the tubular piece.

Abstract: A heel test block comprises a semi-cylinder, a first flat plate and a second flat plate, wherein the side surface of the semi-cylinder comprises a circular arc-shaped surface and a first plane, the first flat plate and the second flat plate are arranged on one side of the first plane, all the parts of the first flat plate have the same thickness, all the parts of the second flat plate have the same thickness, the first flat plate and the second flat plate are arranged in parallel to the first plane, the first flat plate and the second flat plate are arranged on the two sides of the mother line of the semi-cylinder respectively, and the thickness of the first flat plate is less than that of the second flat plate.

Abstract: A gas chromatography system includes at least one gas chromatography subsystem including at least one injector port, and an autosampler.

Abstract: Techniques are described for quantification of molecules in a sample. Mass spectrometry is performed to obtain ionization intensities for precursor and product ions originating from a particular molecule. A first stet of precursor ions having the highest ionization intensities and originating from the particular molecule is determined. For each of the one or precursors in the first set, determined is a second set of one or more product ions that are fragments associated with said each precursor and have the highest ionization in intensities of product ions associated with said each precursor. An intensity sum is calculated for the particular molecule by adding ionization intensities of product ions included in the second sets for the one or more precursors in the first set. The intensity sum is compared to information included in a calibration standard. A quantity of the particular molecule in the sample is determined based on said comparing.

Abstract: The present invention provides methods for analyzing compositions of polypeptides such as antibodies by ionic strength-mediated pH gradient ion exchange chromatography. In some aspects, the methods use a combination of pH gradients and ionic strength gradients to separate the polypeptide from charge variants of the polypeptide. In some aspects, the methods use a stable ionic strength to optimize the pH gradient separation window to separate the polypeptide from charge variants. Such methods are useful for analyzing polypeptide, e.g. antibodies, with a pI greater than 9 or a pI less than 7. In some aspects, the invention provides a multiproduct method for the analysis of polypeptides of varying pI's.