A particle size distribution measurement device includes a cell holding body 31 that holds a measurement cell 2 containing a measurement sample and a dispersion medium and a reference cell 6 containing a reference sample and is rotated by a motor 322, and a cell discrimination mechanism 7 that discriminates the cells 2, 6 passing through a predetermined rotation position by using a magnetic force or electrostatic capacitance.

A system for diagnosing COVID-19 infection. The system includes a biosensor, an electrochemical stimulator-analyzer, and a processing unit. The biosensor is configured to be put in contact with a blood serum sample of a person suspected to be infected of COVID-19 virus. The processing unit is configured to apply an AC potential amplitude to the biosensor while sweeping a frequency range utilizing the electrochemical stimulator-analyzer, recording an electrochemical impedance spectroscopy (EIS) associated with the blood serum sample utilizing the electrochemical stimulator-analyzer, calculating a charge transfer resistance (R.sub.CT) of the recorded EIS, and detecting a COVID-19 infection of the person based on the calculated R.sub.CT if the calculated R.sub.CT is equal to or more than a threshold value.

A method and system for processing particles contained in a liquid biological sample is presented. The method uses a rotatable vessel for processing particles contained in a liquid biological sample. The rotatable vessel has a longitudinal axis about which the vessel is rotatable, an upper portion having a top opening for receiving the liquid containing the particles, a lower portion for holding the liquid while the rotatable vessel is resting, the lower portion having a bottom, and an intermediate portion located between the upper portion and the lower portion, the intermediate portion having a lateral collection chamber for holding the liquid while the rotatable vessel is rotating. The method employs dedicated acceleration and deceleration profiles for sedimentation and re-suspension of the particles of interest.

Provided herein are methods to characterize preparations of recombinant viral particles using analytical ultracentrifugation. Recombinant viral particles include recombinant adeno-associated viral particles, recombinant adenoviral particles, recombinant lentiviral particles and recombinant herpes simplex virus particles. Variant species of recombinant viral particles including empty capsids and recombinant viral particles with variant genomes (e.g., truncated genomes, aggregates, recombinants) can be identified and quantitated. The methods can be used to characterize preparations of recombinant viral particles regardless of the sequence of the recombinant viral genome or the serotype of the recombinant viral capsid.

An apparatus for determining a vertical position of at least one interface between a first component and at least one second component, the components comprised as different layers in a sample container. The apparatus comprises a first sensing unit and a first light detector configured to generate a first sensing signal, a second sensing unit comprising a second light detector configured to generate a second sensing signal, a driving unit configured to move the sample container, a position sensing unit configured to output a position sensing signal indicative of a vertical position of the sample container, a vertical position determining unit configured to match the first and the second sensing signal such that first and the second sensing signal correspond to identical vertical positions, and to determine the vertical position of the at least one interface in response to the matched sensing signals and the position sensing signal.

Provided herein are methods to characterize preparations of recombinant viral particles using analytical ultracentrifugation. Recombinant viral particles include recombinant adeno-associated viral particles, recombinant adenoviral particles, recombinant lentiviral particles and recombinant herpes simplex virus particles. Variant species of recombinant viral particles including empty capsids and recombinant viral particles with variant genomes (e.g., truncated genomes, aggregates, recombinants) can be identified and quantitated. The methods can be used to characterize preparations of recombinant viral particles regardless of the sequence of the recombinant viral genome or the serotype of the recombinant viral capsid.

A quality check module for characterizing a specimen and/or a specimen container. The quality check module includes an imaging location within the quality check module configured to receive a specimen container containing a specimen, one or more cameras located at one or more viewpoints adjacent to the imaging location, and one or more spectrally-switchable light source including a light panel assembly located adjacent the imaging location and configured to provide lighting for the one or more cameras, the spectrally-switchable light source configured to be operatively switchable between multiple different spectra. Methods of imaging a specimen and/or specimen container and specimen, and specimen testing apparatus including a quality check module adapted to carry out the method are described herein, as are other aspects.

A method for measuring the critical micelle concentration of a surfactant solution is provided. The method includes preparing surfactant solutions with different concentration of the surfactant, measuring transmittance profiles of the surfactant solutions in a dispersion analyser under centrifugal force, translating changes in the transmittance profiles of the surfactant solutions to a sedimentation velocity, and using a relationship between the sedimentation velocity and the surfactant concentration to determine the critical micelle concentration of the surfactant.

The invention provides a method, apparatus and system for separating blood and other types of cellular components, and can be combined with holographic optical trapping manipulation or other forms of optical tweezing. One of the exemplary methods includes providing a first flow having a plurality of blood components; providing a second flow; contacting the first flow with the second flow to provide a first separation region; and differentially sedimenting a first blood cellular component of the plurality of blood components into the second flow while concurrently maintaining a second blood cellular component of the plurality of blood components in the first flow. The second flow having the first blood cellular component is then differentially removed from the first flow having the second blood cellular component. Holographic optical traps may also be utilized in conjunction with the various flows to move selected components from one flow to another, as part of or in addition to a separation stage.

The invention provides a method, apparatus and system for separating blood and other types of cellular components, and can be combined with holographic optical trapping manipulation or other forms of optical tweezing. One of the exemplary methods includes providing a first flow having a plurality of blood components; providing a second flow; contacting the first flow with the second flow to provide a first separation region; and differentially sedimenting a first blood cellular component of the plurality of blood components into the second flow while concurrently maintaining a second blood cellular component of the plurality of blood components in the first flow. The second flow having the first blood cellular component is then differentially removed from the first flow having the second blood cellular component. Holographic optical traps may also be utilized in conjunction with the various flows to move selected components from one flow to another, as part of or in addition to a separation stage.