US 12,455,287 B2
Flow cytometry evaluation for unassociated non-enveloped viral particles
Katherine D. Shives, Aurora, CO (US); Antje Schickert, Arvada, CO (US); Rebecca K. Montange, Louisville, CO (US); and Jeffrey W. Steaffens, Broomfield, CO (US)
Appl. No. 17/441,177
Filed by Sartorious BioAnalytical Instruments, Inc., Bohemia, NY (US)
PCT Filed Feb. 5, 2020, PCT No. PCT/US2020/016808
§ 371(c)(1), (2) Date Sep. 20, 2021,
PCT Pub. No. WO2020/197644, PCT Pub. Date Oct. 1, 2020.
Claims priority of provisional application 62/824,116, filed on Mar. 26, 2019.
Prior Publication US 2022/0268773 A1, Aug. 25, 2022
Int. Cl. G01N 33/569 (2006.01); G01N 1/30 (2006.01); G01N 15/14 (2006.01); G01N 15/00 (2006.01)
CPC G01N 33/56983 (2013.01) [G01N 1/30 (2013.01); G01N 15/1459 (2013.01); G01N 2015/0038 (2013.01)] 20 Claims
 
1. A method for flow cytometry evaluation of a biological material for unassociated non-enveloped viral particles having a non-enveloped viral capsid, the method comprising:
preparing a fluorescently-stained fluid sample for flow cytometry evaluation, the fluorescently-stained fluid sample comprising:
an aqueous liquid medium;
a sample of biological material to be evaluated by flow cytometry for the unassociated non-enveloped viral particles having the non-enveloped viral capsid;
at least one fluorescent stain to fluorescently stain the unassociated non-enveloped viral particles to prepare unassociated labeled particles of virus size dispersed in the aqueous liquid medium, wherein each said unassociated labeled particle comprise a said unassociated non-enveloped viral particle stained with the at least one fluorescent stain, and wherein each said fluorescent stain has a fluorescent emission response when the unassociated labeled particle is subjected to a stimulation radiation;
after the preparing, subjecting the fluorescently-stained fluid sample to flow cytometry evaluation in a flow cytometer, the flow cytometry evaluation comprising flowing the fluorescently-stained fluid sample through an investigation zone of the flow cytometer and in the investigation zone subjecting the fluorescently-stained fluid sample to the stimulation radiation and detecting for the fluorescent emission response from the investigation zone and counting identified occurrences of the unassociated labeled particles; and
the preparing the fluorescently-stained fluid sample comprising fluorescent staining the biological material in a fluid sample composition with a said fluorescent stain to prepare a stained fluid sample composition at an acidic pH in an acidic pH range of from pH 3.0 to pH 6.5.