Abstract: The invention relates to a method for counting cells, such as bacteria and/or somatic cells in liquid samples, such as in dairy products, preferably raw milk. Disclosed is a method comprising a combination of steps that apply dimeric nucleic acid dyes that normally do not penetrate cells (=cell-impermeant dyes), which are rendered cell-permeant by using the right combination of pH, buffer and temperature.

Abstract: The invention relates to methods, reagents and kits for detecting enzyme activity using bioluminescence. In particular, it relates to a novel luciferase assay system with reduced background luminescence to allow for increased detection sensitivity. Provided is a method of detecting luciferase activity in a sample using coelenterazine or an analog thereof as a substrate, comprising: (a) initiating luciferase-catalyzed luminescence production by contacting said sample with a luciferase detection reagent to yield a reaction mixture, said reagent comprising coelenterazine and at least one iodide source in an amount sufficient to reduce the autoluminescence of said coelenterazine, (b) incubating said reagent mixture under conditions suitable to produce luminescence, and (c) measuring the luminescence produced. Also provided are detections reagents and kits for use in such a method.

Abstract: The invention relates to methods, reagents and kits for detecting enzyme activity using bioluminescence. In particular, it relates to a novel luciferase assay system with reduced background luminescence to allow for increased detection sensitivity. Provided is a method of detecting luciferase activity in a sample using coelenterazine or an analog thereof as a substrate, comprising: (a) initiating luciferase-catalyzed luminescence production by contacting said sample with a luciferase detection reagent to yield a reaction mixture, said reagent comprising coelenterazine and at least one iodide source in an amount sufficient to reduce the autoluminescence of said coelenterazine, (b) incubating said reagent mixture under conditions suitable to produce luminescence, and (c) measuring the luminescence produced. Also provided are detections reagents and kits for use in such a method.