Disclosed are validation methods and systems for characterizing the credibility and reproducibility of measurements made by a fluorescence-based analytical instrument.

Synthetic human cell mimic hydrogel particles and their use in cytometric or coulter device applications are described. The synthetic human cell mimic hydrogel particles described herein are selectively tunable to have at least one optical, volumetric, or capacitance property that is substantially similar to a corresponding optical, volumetric, or capacitance property of the human cell mimic hydrogel particle's natural biological cell counterpart.

Disclosed are calibration techniques that can be implemented by a device that conducts biological tests. In certain embodiments, the device for testing a biological specimen includes a receiving mechanism to receive a carrier, a camera module arranged to capture imagery of the carrier, and a processor. Some examples of the processor can detect a calibration mode trigger. In calibration mode, the processor can divide the captured imagery into segments and selectively perform one or more calibration procedures for each segment. Then, the processor records a calibration result for each segment.

A method includes calibrating a cytometric device for analysis of a target cell, by inserting, into the cytometric device, a hydrogel particle. The hydrogel particle has at least one of a background fluorescent property or a spectral property that is substantially similar to the at least one of a background fluorescent property or a spectral property of the target cell. The method also includes measuring at least one property of the hydrogel particle using the cytometric device.

Aspects of the present disclosure include methods for determining a parameter of a photodetector (e.g., a photodetector in a particle analyzer). Methods according to certain embodiments include detecting light from a light source with a photodetector for a first predetermined time interval, detecting a step signal with the photodetector, the step signal indicating a change in a parameter of the light source or a parameter of the photodetector, detecting light from the light source for a second predetermined time interval, integrating data signals over the first predetermined time interval and the second predetermined time interval and determining one or more parameters of the photodetector based on the integrated data signals. Systems (e.g., particle analyzers) having a light source and a photodetector for practicing the subject methods are also described. Non-transitory computer readable storage medium having instructions stored thereon for determining a parameter of a photodetector according to the subject methods is also provided.

Aspects of the present disclosure include methods for detecting events in a flow cytometer. Also provided are methods of detecting cells in a flow cytometer. Other aspects of the present disclosure include methods for determining a level of contamination in a flow cell. Computer-readable media and systems, e.g., for practicing the methods summarized above, are also provided.

A particle detection device includes: a first light source to emit first irradiation light; a first light-collection member; a second light-collection member facing the first reflection surface; a second light source to emit second irradiation light; and a first light-reception element. When the first light source emits the first irradiation light, the first light-reception element detects, as the first incident light, scattered light generated when a particle existing at a detection position in a target space is irradiated with the first irradiation light. When the second light source emits the second irradiation light, the first light-reception element detects, as the first incident light, a light ray of the second irradiation light that is reflected by the first reflection surface and a light ray of the second irradiation light that is reflected by both the first reflection surface and the second reflection surface.

A method includes calibrating a cytometric device for analysis of a target cell, by inserting, into the cytometric device, a hydrogel particle. The hydrogel particle has at least one of a background fluorescent property or a spectral property that is substantially similar to the at least one of a background fluorescent property or a spectral property of the target cell. The method also includes measuring at least one property of the hydrogel particle using the cytometric device.

Methods of determining an ideal gain for a detector in a light detection system of a flow cytometer are provided. Methods of interest include irradiating a flow stream with light from a light source, incrementally increasing the gain of the detector such that the detector collects light from the flow stream at each of a plurality of successively increasing gains, obtaining a baseline noise level from the detector at each gain in the plurality of successively increasing gains, calculating a limit of detection (LoD) for each gain in the plurality of successively increasing gains, and assessing the calculated LoDs to determine the ideal gain. Systems and computer readable storage media for practicing the invention are also provided.

Methods for evaluating performance a diode laser are provided. In embodiments, methods include receiving a laser beam profile of a diode laser, determining first, second and third laser beam widths at first, second and third laser intensities, respectively, for the laser beam profile, computing a first ratio between the second and third laser beam widths, computing a second ratio between the first and second laser beam widths, evaluating laser performance based on the first and second ratios, and outputting a determination regarding the suitability of the laser for use in a flow cytometry setting. Devices for practicing the subject methods are also provided, and include first and second stages configured to receive a diode laser and beam profiler, respectively. Aspects of the invention further include flow cytometers incorporating a diode laser that has been evaluated by the subject method.