Abstract: The primary and/or secondary structure of nucleic acid as well as its content and molecular weight can be analyzed in solutions by light scatter or fluorescence measurements after treatment with 3 or 4 ring aromatic cations which bind to single-stranded nucleic acids by cooperative association and induce their condensation (collapse). Preparative separation of nucleic acids of different types from the mixtures in the solution is also accomplished by the same principle and techniques wherein each condensed acid is removed from solution and the condensation reversed.

Abstract: A process for characterizing sperm motility and viability by staining a sperm sample with Rhodamine 123 and ethidium bromide, and simultaneously measuring the sperm fluorescence emissions at green frequencies 515-575 nm and at red frequencies 600-650 nm, the green counts being correlated with sperm motility and the red counts being correlated with putative dying or dead cells. Additionally, a sample of sperm can be characterized as to type and normality by staining a sample of sperm with acridine orange and simultaneously measuring the sperm fluorescence emissions at green frequencies 515-575 nm and at red frequencies 600-650 nm.