Abstract: A method of taking a sample of an inoculated culture medium and measuring the amount of ATP using a luciferase/luciferin reaction. Additional samples are taken at later time intervals to determine whether anything is growing in the medium. Luciferase/luciferin reagent is immobilized on an absorbent tip of a sampling device in order to stabilize the luciferase/luciferin reagent and to provide a convenient means to combine the luciferase/luciferin reagent with the sample. A counting tube containing an extraction reagent is employed to extract intracellular ATP from the sample. Chlorhexadine diacetate (CDA) is the preferred extraction reagent.

Abstract: A rapid detection of ATP using dried luciferase/luciferin reagent. A liquid that may include an extraction reagent is applied to the testing surface, such as a counter top. A sampling device having a handle and an absorbent tip is wiped across the testing surface. The absorbent tip absorbs the sample. The sample is then placed in a counting tube. Luciferase/luciferin reagent is immobilized on the absorbent tip of the sampling device or in the bottom of a counting tube. In either case, the liquid rehydrates the luciferase/luciferin reagent allowing ATP present in the sample to react with the luciferase. Light produced by the reaction is measured with a luminometer.