Abstract: Nonporous polymer beads having an average diameter of about 1-100 microns are suitable for chromatographic separation of mixtures of nucleic acids when the polymer beads are alkylated with alkyl chains having at least three carbon atoms. The polymer beads provide efficient separation of nucleic acids using ion-pair reverse phase chromatography.

Abstract: A method detecting the presence or concentration of an analyte in a sample is described in which the sample is mixed with a particulate reagent to form a stable flowable suspension prior to introduction of the sample into an analytical device or detector in order to eliminate memory effects. Preconcentration of the sample bound to the particulate reagent improves sensitivity of the analytical method.

Abstract: Liquid chromatography separation columns can be protected from contamination with particulate and dissolved contaminants by the use of a thin protective pad which removes contaminants from a sample stream prior to separation of the sample on the separation column. The protective pad may be in the form of a guard disk positioned inline or directly contacting the separation column.

Abstract: In an analytical method for determining the presene or concentration of analyte in a solution comprising detecting a dissolved detectable substance in solution by passing a solution containing a detectable substance through a detection device for determining the presence of concentration of detectable substance in the solution, the improvement including mixing the solution with one or more particulate reagents to form a suspension, thereby modifying the solution to yield a concentration of total detectable substance which correlates with the concentration of original analyte, and passing the solution through the detecting device. The particles can be used to replace an analyte with a detectable substance or an intermediate which can be reacted in solution to form a detectable substance. Alternatively, the particles can be used to suppress or remove an interfering substance.