Coulter International Corp.

University of California

Chiranjit Deka

Kristie M Gordon

Gene G-y Shen

Stephen Szydlo

Song Y Lee

Carlos M Rodriguez

Mark A Wells

Tsong-Tseh Tsay

James L Wyatt

Allan F Horton

John A Steinkamp

Carlos Reyes

The dyes of the present invention are useful for many purposes that include markers or tags for detecting the presence of a molecule or compound to which they are bound. The dyes may be either red-excitable or blue-excitable. The dyes of the invention are particularly well suited for staining of nucleic acids. For example, these dyes are particularly suitable for staining of RNA in reticulocytes. In another exemplary application, these dyes are suitable for staining DNA in nucleated red blood cells. Typically, when used in staining of nucleic acids, the dyes are formulated into reagent solutions. In addition, the invention provides compositions and methods for facilitating rapid transport of dye molecules through a cell membrane. Such rapid staining requires that a sample be contacted with a dye composition of the invention in the presence of at least one surfactant and optionally, a sulfonic acid or a salt thereof.

Dyes and methods of detection of nucleic acid in immature red blood cells

Dyes and methods of reticulocyte enumeration

A rapid fluorescence staining method for facilitating flow cytometry analysis of reticulocytes is described. The method comprises contacting cells with a cocktail containing a detergent, sphering agent, and a cell impermeable dye, such as TO-PRO-3, for about one minute. Advantageously, the inventors have found that the cocktail permits the dye to penetrate the cell membrane rapidly.

Methods and compositions for rapid staining of nucleic acids in whole cells

A method and apparatus for differentiating and enumerating the five major sub-populations of leukocytes in a blood sample (i.e., lymphocytes, monocytes, eosinophils, neutrophils and basophils) uses multiangle light scatter and DC (Coulter) volume measurements. Light scattering characteristics of the leukocytes are determined within five different angular ranges, all being lower than 40 degrees. The invention is particularly useful in differentiating and enumerating the basophil sub-population which has heretofore required more complex apparatus and/or chemical processing.

Method and apparatus for differentiating and enumerating leukocytes

A method for enumerating and distinguishing between blood cell populations in a biological sample includes the steps of contacting a biological sample with a cell membrane-permeant, red-excited, nucleic acid binding dye, without significantly disrupting the integrity of the cells; exciting this sample with light in one red wavelength; and measuring fluorescence emitted from different cell populations in the sample. This method is particularly desirable for enumerating different WBC subpopulations using flow cytometry. This method is also useful for enumerating reticulocytes or NRBC or mature RBC. This method is enhanced by pretreating the sample with a nucleic acid-specific blocking agent. Dyes useful in this method include, without limitation, SYTO&reg;17 dye, SYTO&reg;159 dye, SYTO&reg;60 dye, SYTO&reg;61 dye, SYTO&reg;62 dye, SYTO&reg;63 dye, and SYTO&reg;64 dye.

Method for enumerating blood cells

Time-resolved fluorescence decay measurements for flowing particles. An apparatus and method for the measurement and analysis of fluorescence for individual cells and particles in flow are described, wherein the rapid measurement capabilities of flow cytometry and the robust measurement and analysis procedures of time-domain fluorescence lifetime spectroscopy are combined. A pulse-modulated cw laser is employed for excitation of the particles. The characteristics and the repetition rate of the excitation pulses can be readily adjusted to accommodate for fluorescence decays having a wide range of lifetimes.

Time-resolved fluorescence decay measurements for flowing particles

Growing community of inventors

Miami, FL, United States of America

Chiranjit Deka