Abstract: Discrete magnetic nanoparticles synthesized using a layer-by-layer technique are disclosed. The nanoparticles contain a magnetic core having a large magnetic moment, a plurality of layers and an exterior coating. The nanoparticles have utility in a wide range of biological and bioanalytical applications.

Abstract: A method for detecting lipoarabinomannan in a biological sample is described, including the step of contacting the biological sample with at least one acid selected from the group consisting of perchloric acid, trifluoroacetic acid, and sulfosalicylic acid. Methods for diagnosing diseases, including tuberculosis, and kits for the described methods are also presented.

Abstract: Discrete magnetic nanoparticles synthesized using a layer-by-layer technique are disclosed. The nanoparticles contain a magnetic core having a large magnetic moment, a plurality of layers and an exterior coating. The nanoparticles have utility in a wide range of biological and bioanalytical applications.

Abstract: This disclosure relates to methods and apparatuses for simultaneous measurement of multiple analytes in samples. This disclosure relates to methods and apparatuses for determining the concentration of one or more analytes in a fluid sample without use of a calibrant.

Abstract: The present invention provides a new class of Raman-active reagents for use in biological and other applications, as well as methods and kits for their use and manufacture. Each reagent includes a Raman-active reporter molecule, a binding molecule, and a surface enhancing particle capable of causing surface enhanced Raman scattering (SERS). The Raman-active reporter molecule and the binding molecule are affixed to the particle to give both a strong SERS signal and to provide biological functionality, i.e. antigen or drug recognition. The Raman-active reagents can function as an alternative to fluorescence-labeled reagents, with advantages in detection including signal stability, sensitivity, and the ability to simultaneously detect several biological materials. The Raman-active reagents also have a wide range of applications, especially in clinical fields (e.g., immunoassays, imaging, and drug screening).

Abstract: The present invention provides a new class of Raman-active reagents for use in biological and other applications, as well as methods and kits for their use and manufacture. Each reagent includes a Raman-active reporter molecule, a binding molecule, and a surface enhancing particle capable of causing surface enhanced Raman scattering (SERS). The Raman-active reporter molecule and the binding molecule are affixed to the particle to give both a strong SERS signal and to provide biological functionality, i.e. antigen or drug recognition. The Raman-active reagents can function as an alternative to fluorescence-labeled reagents, with advantages in detection including signal stability, sensitivity, and the ability to simultaneously detect several biological materials. The Raman-active reagents also have a wide range of applications, especially in clinical fields (e.g., immunoassays, imaging, and drug screening).

Abstract: The invention provides nanoparticles and nanoparticle conjugates comprising one or more redox-active species, methods of making nanoparticles and nanoparticle conjugates, and methods for using nanoparticles and nanoparticle conjugates, for example, as diagnostic agents for the detection of various analytes.

Abstract: The present invention provides a new class of Raman-active reagents for use in biological and other applications, as well as methods and kits for their use and manufacture. Each reagent includes a Raman-active reporter molecule, a binding molecule, and a surface enhancing particle capable of causing surface enhanced Raman scattering (SERS). The Raman-active reporter molecule and the binding molecule are affixed to the particle to give both a strong SERS signal and to provide biological functionality, i.e. antigen or drug recognition. The Raman-active reagents can function as an alternative to fluorescence-labeled reagents, with advantages in detection including signal stability, sensitivity, and the ability to simultaneously detect several biological materials. The Raman-active reagents also have a wide range of applications, especially in clinical fields (e.g., immunoassays, imaging, and drug screening).

Abstract: The present invention provides a new class of Raman-active reagents for use in biological and other applications, as well as methods and kits for their use and manufacture. Each reagent includes a Raman-active reporter molecule, a binding molecule, and a surface enhancing particle capable of causing surface enhanced Raman scattering (SERS). The Raman-active reporter molecule and the binding molecule are affixed to the particle to give both a strong SERS signal and to provide biological functionality, i.e. antigen or drug recognition. The Raman-active reagents can function as an alternative to fluorescence-labeled reagents, with advantages in detection including signal stability, sensitivity, and the ability to simultaneously detect several biological materials. The Raman-active reagents also have a wide range of applications, especially in clinical fields (e.g., immunoassays, imaging, and drug screening).

Abstract: A process of detection of the causative agent of Johne's disease (Mycobacterium avium subsp. paratuberculosis) (MAP) by detecting shedding of surface protein of MAP. A preferred way is use of surface enhanced Raman Spectroscopy. The system of detecting MAP shedding of protein provides early detection and diagnosis, and therefore allows early treatment for Johne's disease in ruminant animals.

Abstract: Raman Active Reagents (ERLs) are developed which use a nanoparticle substrate substantially covered with a mixed monolayer derived from a Raman active reporter molecule and an analyte binding molecule that both bind to the surface of the nanoparticle and thereby avoid the necessity for separate synthesis of a bifunctional linker molecule in making the ERL.

Abstract: A process of detection of the causative agent of Johne's disease (Mycobacterium avium subsp. paratuberculosis) (MAP) by detecting shedding of surface protein of MAP. A preferred way is use of surface enhanced Raman Spectroscopy. The system of detecting MAP shedding of protein provides early detection and diagnosis, and therefore allows early treatment for Johne's disease in ruminant animals.

Abstract: A system and method for detecting a detectably labeled cell or component thereof in a sample comprising one or more cells or components thereof, at least one cell or component thereof of which is detectably labeled with at least two detectable labels. In one embodiment, the method comprises: (i) introducing the sample into one or more flow cells of a flow cytometer, (ii) irradiating the sample with one or more light sources that are absorbed by the at least two detectable labels, the absorption of which is to be detected, and (iii) detecting simultaneously the absorption of light by the at least two detectable labels on the detectably labeled cell or component thereof with an array of photomultiplier tubes, which are operably linked to two or more filters that selectively transmit detectable emissions from the at least two detectable labels.

Abstract: Improved detection and enumeration of magnetic particles in a flowing stream by enveloping the particle-containing sample stream with buffer streams from the sides and from the top, thus individualizing the particles and navigating the sample stream as a single-file flow into the proximity of sensors embedded underneath the flow channel. At the same time, larger physical size of the flow channel alleviates problems such as channel clogging. Magnetic particles can represent any analyte of interest, such as biomolecules or bacterial cells, which are labeled with magnetic labels.

Abstract: An improvement in heterogeneous immunoassays to significantly reduce assay time, from as much as 50% up to 90% of what used to be typical assay times. The improvement involves rotating the captured substrate during incubation times for antigen capture and during incubation times for sample labeling.

Abstract: The invention provides nanoparticles comprising one or more redox-active species, methods of making such nanoparticles, and methods for using such nanoparticles, for example, as diagnostic agents for the detection of various analytes.

Abstract: Method and apparatus for manipulating and monitoring analyte flowing in fluid streams. A giant magnetoresistive sensor has an array of sensing elements that produce electrical output signals which vary in dependence on changes in the magnetic field proximate the sensing elements. The analyte is included in a stream, such that the stream has a magnetic property which is dependent on the concentration and distribution on the analyte therein. The stream is flowed past the giant magnetoresistive sensor and in sufficiently close proximity to cause the magnetic properties of the stream to produce electrical output signals. The electrical output signals are monitored as an indicator of analyte concentration or distribution in the stream flowing past the GMR sensor. Changes in the magnetic field produced by the background stream are introduced by analyte molecules, whose presence in the flow past the GMR will effect the output reading.

Abstract: Method and apparatus for manipulating and monitoring analyte flowing in fluid streams. A giant magnetoresistive sensor has an array of sensing elements that produce electrical output signals which vary in dependence on changes in the magnetic field proximate the sensing elements. The analyte is included in a stream, such that the stream has a magnetic property which is dependent on the concentration and distribution on the analyte therein. The stream is flowed past the giant magnetoresistive sensor and in sufficiently close proximity to cause the magnetic properties of the stream to produce electrical output signals. The electrical output signals are monitored as an indicator of analyte concentration or distribution in the stream flowing past the GMR sensor. Changes in the magnetic field produced by the background stream are introduced by analyte molecules, whose presence in the flow past the GMR will effect the output reading.

Abstract: An acoustic wave based-chemical sensor utilizing a crystal substrate and a coating of at least two blended materials is disclosed. The blended materials comprise a combination of (a) a high glass transition temperature polymer or a material of high melting point, and (b) a low glass transition temperature polymer or a material having a low melting point. Transducers are connected to the crystal substrate to generate an alternating potential across the crystal substrate, which in turn causes the crystal to resonate due to the converse piezoelectric effect. The blended coating absorbs the analyte, thus changing the mass of the chemical sensor, and accordingly changing its resonant frequency. The transducers detect this change in resonant frequency to indicate that the analyte is present.

Abstract: An acoustic wave based-chemical sensor containing a crystal substrate and a coating of small particulate matter is disclosed. The small particulate matter can be graphite particles. Transducers are connected to the crystal substrate to generate an alternating potential across the crystal substrate, which in turn causes the crystal to resonate due to the converse piezoelectric effect. The coating absorbs the analyte, thus changing the mass of the sensor, and accordingly changing its resonant frequency. The transducers detect this change in resonant frequency to indicate that the analyte is present. The use of small particulate matter results in a coating having a large surface area which facilitates mass uptake of large amounts of VOCs, improved acoustic properties even with relatively thick coatings, and a high operational temperature range.