Abstract: Devices for detecting particle sizes and distributions using focused light scattering techniques, by passing a sample through a focused beam of light, are disclosed. In one embodiment, the devices include one or more lasers, whose light is focused into a narrow beam and into a flow cell, and dispersions are passed through the flow cell using hydrodynamic sample injection. In another embodiment, a plurality of lasers is used, optionally with hydrodynamic sample injection. Particles pass through and scatter the light. The scattered light is then detected using scatter and extinction detectors, and, optionally, fluorescence detectors, and the number and size of the particles is determined. Particles in the size range of 0.1 to 10 ?m can be measured. Using the device, significantly smaller particles can be detected than if techniques such as EQELS, flow cytometry, and other conventional devices for measuring biological particles.

Abstract: Methods for using focused light scattering techniques for the optical sensing of biological particles suspended in a liquid medium are disclosed. The optical sensing enables one to characterize particles size and/or distribution in a given sample. This, in turn, allows one to identify the biological particles, determine their relative particle density, detect particle shedding, and identify particle aggregation. The methods are also useful in screening and optimizing drug candidates, evaluating the efficacy and dosage levels of such drugs, and in personalized medicine applications.

Abstract: Devices for detecting particle sizes and distributions using focused light scattering techniques, by passing a sample through a focused beam of light, are disclosed. In one embodiment, the devices include one or more lasers, whose light is focused into a narrow beam and into a flow cell, and dispersions are passed through the flow cell using hydrodynamic sample injection. In another embodiment, a plurality of lasers is used, optionally with hydrodynamic sample injection. Particles pass through and scatter the light. The scattered light is then detected using scatter and extinction detectors, and, optionally, fluorescence detectors, and the number and size of the particles is determined. Particles in the size range of 0.1 to 10 ?m can be measured. Using the device, significantly smaller particles can be detected than if techniques such as EQELS, flow cytometry, and other conventional devices for measuring biological particles.

Abstract: Diagnostic methods for determining whether an individual will benefit from a particular anti-thrombotic therapeutic agent are disclosed. The methods involve obtaining a biological sample that comprises platelets, from a patient who has been pre-administered a particular therapeutic agent, which is an antagonist of a receptor associated with the biochemical pathways involved in platelet aggregation, and exposing the platelets to an agonist of the receptor. If the antagonist is ineffective, the platelets will eject microparticles, will have a different size distribution than platelets not exposed to the agonist, and will experience a change in their surface charge. In one embodiment, the diagnostic methods involve using single particle optical sizing techniques to determine the presence of such ejected microparticles, or a change in platelet size due to its activation by the agonist.

Abstract: Methods for using focused light scattering techniques for the optical sensing of biological particles suspended in a liquid medium are disclosed. The optical sensing enables one to characterize particles size and/or distribution in a given sample. This, in turn, allows one to identify the biological particles, determine their relative particle density, detect particle shedding, and identify particle aggregation. The methods are also useful in screening and optimizing drug candidates, evaluating the efficacy and dosage levels of such drugs, and in personalized medicine applications.

Abstract: Methods for using focused light scattering techniques for the optical sensing of biological particles suspended in a liquid medium are disclosed. The optical sensing enables one to characterize particles size and/or distribution in a given sample. This, in turn, allows one to identify the biological particles, determine their relative particle density, detect particle shedding, and identify particle aggregation. The methods are also useful in screening and optimizing drug candidates, evaluating the efficacy and dosage levels of such drugs, and in personalized medicine applications.

Abstract: A new device capable of measuring the number of particles present in a colloidal suspension is disclosed, which includes a forward scatter detector, an extinction detector, a laser beam, a cylindrical lens with which to create a plane of light through which particles can pass, and the various pumps and tubing needed to pass the colloidal suspension through the plane of light. The device is particularly designed for measuring particles which have different refractive indices, and which are in the size range of between about 0.7 to 2 microns. The device can determine the presence or absence of biological particles of interest in a given sample, by incubating a sample with a given ratio of active particles and marker particles, and determining whether the ratio of active particles and marker particles has changed. Additional binding and/or non-binding particles can also be present, and kits including the particles are also disclosed.

Abstract: A new device capable of measuring the number of particles present in a colloidal suspension is disclosed, which includes a forward scatter detector, an extinction detector, a laser beam, a cylindrical lens with which to create a plane of light through which particles can pass, and the various pumps and tubing needed to pass the colloidal suspension through the plane of light. The device is particularly designed for measuring particles which have different refractive indices, and which are in the size range of between about 0.7 to 2 microns. The device can determine the presence or absence of biological particles of interest in a given sample, by incubating a sample with a given ratio of active particles and marker particles, and determining whether the ratio of active particles and marker particles has changed. Additional binding and/or non-binding particles can also be present, and kits including the particles are also disclosed.

Abstract: Methods for using focused light scattering techniques for the optical sensing of biological particles suspended in a liquid medium are disclosed. The optical sensing enables one to characterize particles size and/or distribution in a given sample. This, in turn, allows one to identify the biological particles, determine their relative particle density, detect particle shedding, and identify particle aggregation. The methods are also useful in screening and optimizing drug candidates, evaluating the efficacy and dosage levels of such drugs, and in personalized medicine applications.