Becton Dickinson and Company Limited

Other

Smithkline Beckman Corporation

Chronomed, Inc.

Alex M Saunders

Chin-Hai Chang

Paul Alexander Saunders

Methods and kits for performing a two-phase optical assay for one or more than one analyte without intrinsic optical contrast in a sample are disclosed. The method requires use of a functionalized microparticle immobilized with two or more than functional components and an additional set of one or more than one functional component. The assay can be performed in one single container and does not need a wash step.

Two-phase optical assays for analytes of no intrinsic opitcal contrast

The present invention provides an assay for an analyte in solution. The assay relies, in part, on associating two catalytic activities in close proximity to each other (e.g., by conjugating each enzyme to a ligand that binds the analyte) and providing substrates that produce a colored product only when both activities are bound to the same molecule in solution.

Ligand based solution assay for low concentration analytes

A lysing agent and a method for utilizing the lysing agent in the identification and enumeration of cells of a select subclass of leucocytes is provided. The lysing agent includes formaldehyde, an alkali or alkaline earth salt of a weak acid and a polyhydric alcohol.

Lysing agent for analysis of peripheral blood cells

The present invention is directed to a method for separating mononuclear cells from other cells in a blood sample which is more rapid than the currently used density gradient material and which provides a better separation than methods utilizing thixotropic, gel-like material. In the method, a water soluble density gradient material is placed in a centrifuged tube. A water insoluble, thixotropic, gel-like substance is also placed in the container. A blood sample is placed in the container and the container is centrifuged for a time during which various components interchange positions and the gel-like substance forms a barrier between the mononuclear cells and the other cells of the blood sample.

Blood partitioning method

Blood partitioning apparatus

A method for identifying subpopulations of cells of interest without interference from other cells. In the method, a sample of at least three (3) types of cells, including a first and second type of cell which form a subpopulation of cells of interest and a third type of cell which interferes with the identification of said subpopulation, is divided into at least two (2) aliquots. A first antibody which is specific for the third type of interfering cells but not for the subpopulation, is labeled with two (2) fluorochromes, each of the fluorochromes having distinct emission spectra. The labeled first antibody is then added to a first one of the sample aliquots so as to label the third type of cells with the first antibody. A first analysis is performed by analyzing each cell to determine the fluorescence emitted and to count the third type of cells so as to distinguish the third type of cells from the subpopulation. The information obtained from the first analysis is retained for subsequent use. The above steps are repeated for the subpopulation of cells of interest and a second analysis is obtained. The retained information from the first analysis is used to remove the effect of the third type of interfering cells and to provide a direct proportional analysis of the first and second types of cells in the subpopulation of cells of interest.

Method for elimination of selected cell populations in analytic cytology

Disclosed is a process of preparing blood spreads for microscopical examination wherein a smooth and homogeneous plasma layer is obtained. A combination of steps including timely fixation for the purpose of cell preservation, producing a cross-linked matrix in the plasma and performing of chemical reactions by diffusing reagents across an interface, are performed for the purpose of stabilizing both the cell shape and the smoothness and homogeneity of the plasma layer, while the fresh and still wet blood spread is immersed in a non-polar, water immisicible, solvent.

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San Carlos, CA, United States of America

Alex M Saunders