A particle charger is provided with: a filter (28) partitioning the inside of a housing (20) into a first space (29) and second space (30); a particle introducer (22) for introducing a particle into the first space; a gas ion supplier (10) for supplying the first space with a gas ion; a potential gradient creator (26, 27, 31) for creating a potential difference within the housing so as to make the gas ion and a charged particle resulting from a contact of the aforementioned particle with the gas ion move toward the second space; an AC voltage supplier (32, 33) for applying AC voltages having a phase difference to the neighboring electrodes (28a, b) included in the filter; a controller (35) for performing a control for applying, to the plurality of electrodes, predetermined voltages so as to allow the charged particle to pass through a gap between the electrodes while trapping the gas ion by the electrodes; and a charged particle extractor (23, 25, 34) for extracting the charged particle admitted to the second space to the outside of the housing. By this configuration, the occurrence frequency of the multi-charging is suppressed.

A method for flow cytometry evaluation of unassociated non-enveloped viral particles having a non-enveloped viral capsid includes preparing a fluorescently-stained fluid sample in which at least one fluorescent staining step is performed at an acidic pH in an acidic pH range and then subjecting the fluorescently-stained fluid sample to flow cytometry evaluation. A kit includes a plurality of sealed container with a first sealed container containing a fluorescent stain composition and a second sealed container including an aqueous dilution liquid at an acidic pH.

A particle sensor for measuring size and concentration properties of particles in a gas includes a bipolar diffusion charger configured to charge particles within a received gas sample by the collision of the received particles with and transfer of charge from both positive and negative ions concurrently. At least one electrometer detects the charge of received particles thereby charged. The net, positive, negative or total charge on the bipolarly charged particles has a low sensitivity to variations in the absolute rate of charge generation in the bipolar diffusion charger. A sensor for a ratio of ion charge mobilities in a bipolar diffusion charger employs an ion trap between the bipolar diffusion charger and at least one electrometer.

A particle detection method in which particles in a sample are detected includes: a mounting step of mounting, on a stage portion, a fluid device including a channel through which the particles can move; an irradiation step of irradiating the channel with illumination light; and a detection step of detecting scattered light generated from the particles by irradiation with the illumination light. In the irradiation step, the illumination light is converged such as to enter the channel by passing through, among side surfaces of the channel, only the first side surface that faces an illumination light incident direction.

A particle vapor reactor (PVR) includes a reactor body with a fluid flow conduit having an inlet end and an outlet end, the crossection of the conduit having a circular geometry at the inlet end, a rectangular geometry at its midsection, and a circular geometry at its outlet end. The PVR conduit defines a saturator section and a condenser section. A compact condensation particle counter (CPC) including the reactor is also disclosed. The CPC also includes a sample inlet, a fluid inlet section, a heater section, and a detector section.

The present invention relates to a method for determining an estimate of a concentration of particles E(C), wherein a sample of predetermined volume is divided into a number (N) of compartments, the (N) compartments comprise or consist of different sample volumes (v.sub.i) and/or different dilution factors (d.sub.i) of the sample, at least part of the particles that are present in any of the (N) compartments provide a measurable signal and the estimated concentration of particles E(C) is a function of measured signals, as well as an apparatus for use in the inventive method, uses of the inventive method, a sample holder and a kit for use in the inventive method.

In-line holography to create images of a specimen, such as one or more particles dispersed in a transparent medium. Analyzing these images with results from light scattering theory yields the particles' sizes with nanometer resolution, their refractive indexes to within one part in a thousand, and their three dimensional positions with nanometer resolution. This procedure can rapidly and directly characterize mechanical, optical and chemical properties of the specimen and its medium.

There is provided a particle detection apparatus (30) comprising: a channel (32) including an inlet and at least one channel wall, the inlet permitting light to be introduced into the channel (32), the or each channel wall being arranged to define a channel path through which light may propagate; a light source (34) configured to introduce light into the channel (32) via the inlet, the channel (32) being shaped to guide the light to propagate along the channel path for illuminating a particle or a plurality of particles located in the channel path; and a monitoring device (36) configured to detect scattered light that is created by the illumination of the or each particle by the guided light and that leaves the channel (32) by passing through the or each channel wall.

The invention relates to a device and method for reducing the reduction in intensity of a fluorescence dye by laser light when determining fluorescence and the number of antibodies on exosomes, comprising means for storing different measurement points of various differently coloured lasers in a measuring cell at certain measurement positions, the focusing of the laser beam interacting with the sample being recorded in a video camera as the centre of a convergent beam bundle.

A filter toxin and antigen detector assembly for detecting the presence or absence of toxins or antigens within air handling systems, ventilators, respirators, continuous positive airway pressure devices (CPAP), and bilevel positive airway pressure (BIPAP) devices is disclosed. The filter toxin and antigen detectors may be attached to an air filter, or placed (such as in the form of a test cartridge or test strip) onto a port or other portion of a respiration device to determine if the device is clean for further medical use. The filter toxin and antigen detectors disclosed herein utilize lateral flow immunochromatographic assay technology having a sample window allowing air flow therethough. The filter toxin and antigen detector will give an immediate presence indication, such as by changing color, thus providing a fast indication of whether or not harmful toxins or antigens are present within an airborne environment.