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 .Math. 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.

A specimen measurement apparatus may include: an aspirator via which a specimen is aspirated. A flow path may be connected to the aspirator. A first pump may be connected to the flow path. A second pump may be connected to the flow path. A controller may select and cause either the first pump or the second pump to aspirate the specimen via the aspirator.

In an example implementation, a method of microfluidic filtering includes activating a first fluid pump within a microfluidic channel to cause a forward flow of fluid through the microfluidic channel and through a filter of a filter loop. The filter loop intersects the microfluidic channel at a loop entry and at a loop exit. The method includes activating a second fluid pump to cause a reverse flow of fluid through the filter.

Systems and methods for analyzing blood samples, and more specifically for performing a white blood cell (WBC) differential analysis. The systems and methods screen WBCs by means of fluorescence staining and a fluorescence triggering strategy. As such, interference from unlysed red blood cells (RBCs) and fragments of lysed RBCs is substantially eliminated. The systems and methods also enable development of relatively milder WBC reagent(s), suitable for assays of samples containing fragile WBCs. In one embodiment, the systems and methods include: (a) staining a blood sample with an exclusive cell membrane permeable fluorescent dye, which corresponds in emission spectrum to an excitation source of a hematology instrument; (b) using a fluorescence trigger to screen the blood sample for WBCs; and (c) using measurements of (1) axial light loss, (2) intermediate angle scatter, (3) 90 polarized side scatter, (4) 90 depolarized side scatter, and (5) fluorescence emission to perform a differentiation analysis.

Systems and methods for analyzing blood samples, and more specifically for performing a nucleated red blood cell (nRBC) analysis. The systems and methods screen a blood sample by means of fluorescence staining and a fluorescence triggering strategy, to identify nuclei-containing particles within the blood sample. As such, interference from unlysed red blood cells (RBCs) and fragments of lysed RBCs is substantially eliminated. The systems and methods also enable development of relatively milder reagent(s), suitable for assays of samples containing fragile white blood cells (WBCs). In one embodiment, the systems and methods include: (a) staining a blood sample with an exclusive cell membrane permeable fluorescent dye; (b) using a fluorescence trigger to screen the blood sample for nuclei-containing particles; and (c) using measurements of light scatter and fluorescence emission to distinguish nRBCs from WBCs.

Provided herein are systems and methods for analyzing blood samples, and more specifically for performing a basophil analysis. In one embodiment, the systems and methods include: (a) staining a blood sample with an exclusive cell membrane permeable fluorescent dye; and then (b) using measurements of light scatter and fluorescence emission to distinguish basophils from other WBC sub-populations. In one embodiment, the systems and methods include performing a basophil cluster analysis of the blood sample, based on the combination of light scatter and fluorescence measurements.

The disclosure relates to devices and methods for analyzing blood cells in a sample. In various embodiments, the present disclosure provides devices and methods of performing complete blood count (CBC) testing. In various embodiments, the present disclosure provides a cartridge device and a reader instrument device, wherein the reader instrument device receives, operates, and/or actuates the cartridge device. In various embodiments, the present disclosure provides a method of using a device as disclosed herein for analyzing blood cells in a sample.

The disclosure relates to devices and methods for analyzing particles in a sample. In various embodiments, the present disclosure provides devices and methods for cytometry and additional analysis. In various embodiments, the present disclosure provides a cartridge device and a reader instrument device, wherein the reader instrument device receives, operates, and/or actuates the cartridge device. In various embodiments, the present disclosure provides a method of using a device as disclosed herein for analyzing particles in a sample.

This disclosure provides an impedance cytometer which includes a carrier that can be attached to a living being, with a biosensor mounted thereto. The bio sensor includes a microfluidic flow channel, formed in the carrier, and an impedance circuit. The microfluidic flow channel accommodates passage of a particle therethrough. The impedance circuit, connected to the microfluidic flow channel, includes a signal generator that produces a high-frequency drive signal applied to the flow channel to produce a biosensor output signal having high-frequency variation resulting from the drive signal and low-frequency variation resulting from impedance variation within the flow channel during the particle's passage. A lock-in amplifier is disposed to (i) amplify the bio sensor output signal, (ii) mix the amplified signal with the drive signal, and (iii) frequency-filter the mixed, amplified signal to output an impedance signal representing the low-frequency impedance variation resulting from the passage of the particle. Embodiments enable wearable, personalized cytometry.

Systems and methods are provided for sample processing. A device may be provided, capable of receiving the sample, and performing one or more of a sample preparation, sample assay, and detection step. The device may be capable of performing multiple assays. The device may comprise one or more modules that may be capable of performing one or more of a sample preparation, sample assay, and detection step. The device may be capable of performing the steps using a small volume of sample.