Abstract: A method for evaluating a biological material for unassociated virus-size particles having a particular epitope uses a fluorescent antibody stain specific for binding with the epitope and a fluid sample with the virus-size particles and fluorescent antibody stain is subjected to flow cytometry with identification of fluorescent emission detection events indicative of passage through a flow cell of a flow cytometer of unassociated labeled particles of virus size including such a virus-size particle and fluorescent antibody stain.

Abstract: A method for evaluating a biological material for unassociated virus-size particles having a particular epitope uses a fluorescent antibody stain specific for binding with the epitope and a fluid sample with the virus-size particles and fluorescent antibody stain is subjected to flow cytometry with identification of fluorescent emission detection events indicative of passage through a flow cell of a flow cytometer of unassociated labeled particles of virus size including such a virus-size particle and fluorescent antibody stain.

Abstract: A method for evaluating a biological material for unassociated virus-size particles having a particular epitope uses a fluorescent antibody stain specific for binding with the epitope and a fluid sample with the virus-size particles and fluorescent antibody stain is subjected to flow cytometry with identification of fluorescent emission detection events indicative of passage through a flow cell of a flow cytometer of unassociated labeled particles of virus size including such a virus-size particle and fluorescent antibody stain.

Abstract: A method is described for training a machine learning model to predict virus titer from an image or a sequence of images of a cell culture containing a virus population. The trained machine learning model allows a prediction of virus titer to be made much earlier than in the standard virus plaque assay, for example in 6 or 8 hours after initial inoculation of the cell culture with the virus sample. The method includes the steps of: (1) obtaining a training set in the form of a plurality of sets of images of virus-treated cell cultures from a plurality of experiments at one or more time points from a start time t0 to a final time tfinal, (2) for each experiment, recording at least one numeric virus titer readout of the virus-treated cell culture at the final time tfinal, (3) processing all the images in the training set to acquire a numeric representation of each image, and (4) training one or more machine learning models to make a prediction of a final virus titer on the training set numeric representations.

Abstract: Fluorescent viral particles, including viral particles and a fluorescent dye conjugated to the viral particles, are used for viral contaminant removal testing as part of viral clearance evaluation for biological medical product preparation processes. The conjugated fluorescent dye adds only marginally to viral particle size, but provides versatility both for rapid screening of alternative viral removal approaches during process development and for final process validation, as the fluorescent viral particles have fluorescent activity throughout the viral clearance evaluation process, permitting rapid and consistent quantification of initial test solutions, resulting purified solutions, and intermediate solutions of interest at any point during processing under evaluation.

Abstract: In flow cytometry evaluation for unassociated virus-size particles stained with multiple fluorogenic dyes, the fluid sample is stained with an aqueous diluted dye formulation including multiple fluorogenic dyes. Preparation of the aqueous diluted dye formulation includes first preparatory processing to prepare a concentrated dye formulation with the fluorogenic dyes provided in a dry powder mixture mixed with and dissolved into a first liquid medium comprising DMSO. After the first preparatory processing, aqueous liquid diluent is added to dilute the first liquid medium and while the fluorogenic dyes remain in solution the liquid medium is converted to an aqueous liquid medium, which may include DMSO as a minor molar component but at a significant concentration. The stained fluid sample may include dissolved disaccharide.

Abstract: A method for evaluating a biological material for unassociated virus-size particles having an adenovirus epitope uses a fluorescent antibody stain specific for binding with the epitope and a fluid sample with the virus-size particles and fluorescent antibody stain is subjected to flow cytometry with identification of fluorescent emission detection events indicative of passage through a flow cell of a flow cytometer of unassociated labeled particles of virus size including such a virus-size particle and fluorescent antibody stain.

Abstract: A method for evaluating a biological material for unassociated virus-size particles having a particular epitope uses a fluorescent antibody stain specific for binding with the epitope and a fluid sample with the virus-size particles and fluorescent antibody stain is subjected to flow cytometry with identification of fluorescent emission detection events indicative of passage through a flow cell of a flow cytometer of unassociated labeled particles of virus size including such a virus-size particle and fluorescent antibody stain.

Abstract: A method for evaluating a biological material for unassociated virus-like particles virus size having a particular epitope uses a fluorescent antibody stain specific for binding with the epitope and a fluid sample with the virus-size particles and fluorescent antibody stain is subjected to flow cytometry with identification of fluorescent emission detection events indicative of passage through a flow cell of a flow cytometer of unassociated labeled particles of virus size including such a virus-like particle and fluorescent antibody stain.

Abstract: A method for evaluating a biological material for unassociated virus-size particles of exosomes having a particular epitope uses a fluorescent antibody stain specific for binding with the epitope and a fluid sample with the exosomes and fluorescent antibody stain is subjected to flow cytometry with identification of fluorescent emission detection events indicative of passage through a flow cell of a flow cytometer of unassociated labeled particles of virus size including such an exosome and fluorescent antibody stain.

Abstract: A method for evaluating a biological material for unassociated virus-size particles having a particular epitope uses a fluorescent antibody stain specific for binding with the epitope and a fluid sample with the virus-size particles and fluorescent antibody stain is subjected to flow cytometry with identification of fluorescent emission detection events indicative of passage through a flow cell of a flow cytometer of unassociated labeled particles of virus size including such a virus-size particle and fluorescent antibody stain.

Abstract: A method for evaluating a biological material for unassociated virus-size particles having a particular epitope uses a fluorescent antibody stain specific for binding with the epitope and a fluid sample with the virus-size particles and fluorescent antibody stain is subjected to flow cytometry with identification of fluorescent emission detection events indicative of passage through a flow cell of a flow cytometer of unassociated labeled particles of virus size including such a virus-size particle and fluorescent antibody stain.

Abstract: A method for evaluating a biological material for unassociated virus-size particles of exosomes having a particular epitope uses a fluorescent antibody stain specific for binding with the epitope and a fluid sample with the exosomes and fluorescent antibody stain is subjected to flow cytometry with identification of fluorescent emission detection events indicative of passage through a flow cell of a flow cytometer of unassociated labeled particles of virus size including such an exosome and fluorescent antibody stain.

Abstract: A method for evaluating a biological material for unassociated virus-size particles having an adenovirus epitope uses a fluorescent antibody stain specific for binding with the epitope and a fluid sample with the virus-size particles and fluorescent antibody stain is subjected to flow cytometry with identification of fluorescent emission detection events indicative of passage through a flow cell of a flow cytometer of unassociated labeled particles of virus size including such a virus-size particle and fluorescent antibody stain.

Abstract: A method for evaluating a biological material for unassociated virus-size particles having a particular epitope uses a fluorescent antibody stain specific for binding with the epitope and a fluid sample with the virus-size particles and fluorescent antibody stain is subjected to flow cytometry with identification of fluorescent emission detection events indicative of passage through a flow cell of a flow cytometer of unassociated labeled particles of virus size including such a virus-size particle and fluorescent antibody stain.

Abstract: A method for evaluating a biological material for unassociated virus-size particles having a particular epitope indicative of an adeno-associated virus viral type or an adenovirus viral type uses a fluorescent antibody stain specific for binding with the epitope and a fluid sample with the virus-size particles and fluorescent antibody stain is subjected to flow cytometry with identification of fluorescent emission detection events indicative of passage through a flow cell of a flow cytometer of unassociated labeled particles of virus size including such a virus-size particle and fluorescent antibody stain.

Abstract: A method for evaluating a biological material for unassociated virus-size particles having a particular epitope uses a fluorescent antibody stain specific for binding with the epitope and a fluid sample with the virus-size particles and fluorescent antibody stain is subjected to flow cytometry with identification of fluorescent emission detection events indicative of passage through a flow cell of a flow cytometer of unassociated labeled particles of virus size including such a virus-size particle and fluorescent anti body stain.

Abstract: A method for evaluating a biological material for unassociated virus-size particles having a particular epitope indicative of an adeno-associated virus viral type or an adenovirus viral type uses a fluorescent antibody stain specific for binding with the epitope and a fluid sample with the virus-size particles and fluorescent antibody stain is subjected to flow cytometry with identification of fluorescent emission detection events indicative of passage through a flow cell of a flow cytometer of unassociated labeled particles of virus size including such a virus-size particle and fluorescent antibody stain.

Abstract: A method for evaluating a biological material for unassociated virus-like particles virus size having a particular epitope uses a fluorescent antibody stain specific for binding with the epitope and a fluid sample with the virus-size particles and fluorescent antibody stain is subjected to flow cytometry with identification of fluorescent emission detection events indicative of passage through a flow cell of a flow cytometer of unassociated labeled particles of virus size including such a virus-like particle and fluorescent antibody stain.

Abstract: A method for evaluating a biological material for unassociated virus-size particles having a particular epitope indicative of an adeno-associated virus viral type or an adenovirus viral type uses a fluorescent antibody stain specific for binding with the epitope and a fluid sample with the virus-size particles and fluorescent antibody stain is subjected to flow cytometry with identification of fluorescent emission detection events indicative of passage through a flow cell of a flow cytometer of unassociated labeled particles of virus size including such a virus-size particle and fluorescent antibody stain.