Abstract: A separation method for use in conjunction with bio-analytical techniques, such as cell screening and blood flow measurement, in which a carrier bearing a bio-affecting compound comprising a reporter moiety is contacted with an organic extractant which is immiscible with the carrier, so as to produce distinct extractant and carrier phases, with a major amount of the bio-affecting compound originally associated with the carrier being transferred to the extractant phase. The separation method is particularly useful in performing bio-analytical techniques involving fluorometric determinations, as fluorescence efficiency is increased substantially by transfer of a fluorescent reporter from an aqueous carrier phase to the organic extractant phase, and concentration of the fluorescent reporter in the extractant phase prior to fluorescence measurement.

Abstract: Methods for distinguishing multiple subpopulations of biological particles in a single sample based upon quantitative differences in the fluorescence intensity attributable to one or two fluorochromes with which the biological particles are labelled. The method is used with flow cytometric particle counting techniques to count and sort and biological particles such as the formed elements of blood and other tissue cells. Also disclosed are reagents containing fluorochrome-conjugated antibodies used in the methods.

Abstract: Methods for determining growth rate of cells growing in vivo and in vitro. Cells are labelled with cyanine dyes and changes in plasma membrane cyanine dye levels are used to determine growth rate. Cell growth rate determinations are utilized to monitor transplanted bone marrow cell engraftment and post-surgical corneal epitheal cell growth. The invented methods also are used to determine tumor cell sensitivity to cancer therapeutic agents, yeast sensitivity to antifungal agents, and bacteria sensitivity to antibacterial agents.

Abstract: Methods for reproducibly labelling viable cells with cyanine dyes that do not significantly affect cell viability. Applications for labelled cells include using labelled red blood cells to distinguish post-transfusional bleeding from immunologic reaction and using dilution to measure growth rate of cultured cells.

Abstract: Methods of tracking cells in vivo and for determining in vivo cell lifetimes. Cells are labelled with cyanine dyes and detection is by measuring fluorescence, absorbance, or by detecting nuclear magnetic resonance probes included in the cyanine dyes. Using the invented methods, for example, red blood cell and platelet lifetimes are determined. Also, cells are tracked to determine sites of primary or metastatic tumors, or sites of occult infection. Further, rates at which cells pass through vessels is used to determine blood vessel patency and platelet aggregation.