Abstract: A kit and method for flow cytometry include a liquid dye concentrate for fluorescent staining of virus-size particles with a plurality of fluorogenic dyes in a liquid medium. The liquid dye concentrate includes a plurality of fluorogenic dyes and one or both of (i) the liquid medium comprising a liquid mixture including water and liquid phase organic material and (ii) disaccharide dissolved in the liquid medium.

Abstract: A method for flow cytometry evaluation of unassociated non-enveloped viral particles having a non-enveloped viral capsid includes preparing a fluorescently-stained fluid sample in which at least one fluorescent staining step is performed at an acidic pH in an acidic pH range and then subjecting the fluorescently-stained fluid sample to flow cytometry evaluation. A kit includes a plurality of sealed container with a first sealed container containing a fluorescent stain composition and a second sealed container including an aqueous dilution liquid at an acidic pH.

Abstract: A kit and method for flow cytometry include a liquid dye concentrate for fluorescent staining of virus-size particles with a plurality of fluorogenic dyes in a liquid medium. The liquid dye concentrate includes a plurality of fluorogenic dyes and one or both of (i) the liquid medium comprising a liquid mixture including water and liquid phase organic material and (ii) disaccharide dissolved in the liquid medium.

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: An optical assay device for the detection of an analyte of interest in a sample comprising a support containing channels, an optically functional layer positioned on the support such that the optically functional layer and the support allow for laminar flow of the sample through layers of the device, an attachment layer positioned on the optically functional layer, and an analyte specific receptive layer positioned on the attachment layer.

Abstract: An optical assay device for the detection of an analyte of interest in a sample comprising a support containing channels, an optically functional layer positioned on the support such that the optically functional layer and the support allow for laminar flow of the sample through layers of the device, an attachment layer positioned on the optically functional layer, and an analyte specific receptive layer positioned on the attachment layer.

Abstract: The present invention relates to cost effective analytical instruments for determining the presence or amount of an analyte in a sample. The analytical instruments utilize an assay cartridge which has a sample receiving port and a rotatable carousel containing a plurality of reagent wells. Each reagent well includes a piston element for delivery of reagent to a test surface. The instrument is capable of indexing the assay cartridge to deliver sample and reagents to a test surface in a predetermined and flexibile manner, thus providing an assay protocol which is specific to the type of sample under analysis. The invention also relates to components, features, disposables, reagent delivery systems, accessories, and methods for using such instruments. Appropriate applications include infectious disease testing, cancer detection and monitoring, therapeutic drug level monitoring, allergy testing, environmental testing, food testing, diagnostic testing of human and veterinary samples, and off-line process testing.

Abstract: Compositions for stabilizing polypeptides or antigens are described. These compositions are useful for stabilizing polypeptides or antigens stored in aqueous formulations. Such formulations can be used for various analytical or other methods.

Abstract: Compositions for stabilizing polypeptides or antigens are described. These compositions are useful for stabilizing polypeptides or antigens stored in aqueous formulations. Such formulations can be used for various analytical or other methods.

Abstract: Compositions for stabilizing polypeptides or antigens are described. These compositions are useful for stabilizing polypeptides or antigens stored in aqueous formulations. Such formulations can be used for various analytical or other methods.

Abstract: Method for extracting an antigen from a micro-organism organism of the genus streptococcus contained in a sample including the steps of contacting the sample with reagents which generate hyponitrous acid, further contacting the sample with a base, or contacting the sample with hypochlorite, and neutralizing the sample.

Abstract: An improved immunoassay method and kit have been developed that include a sample pretreatment method and kit employing an alkylating agent that modifies antibodies in the sample to render the antibodies incapable of interfering with analyte detection. Prior to performing the immunoassay, the alkylating agent is inactivated so that it does not modify antibody reagents used in the immunoassay.

Abstract: A stable substrate formulation for an alkaline phosphatase assay includes 5-bromo-4-chloro-3-indolyl phosphate, nitro blue tetrazolium and a 2-amino-2-methyl-1-propanol buffer. Addition of MgCl.sub.2 to this formulation promotes stability.