Apparatus and methods for detecting ATP in a liquid sample
Apparatuses and kits for the detection of ATP in a liquid sample are provided. The apparatuses and kits comprise a liquid reagent composition comprising luciferin and a sampling device having a sampling portion and a handling portion. The sampling portion comprises a fibrous or a foam material and is adapted to acquire and releasably retain a predetermined volume of a liquid sample or a sample of residue from a surface. The sampling device comprises a dry coating or a liquid coating, the coating including an effective amount of a pH-adjusting reagent that, when contacted with a liquid reagent composition having a pH 6.8 or lower, changes the pH of the liquid reagent composition to 6.9 or higher. Methods of use of the apparatus or kit are also provided.
1. A method, comprising:
using a sampling device to obtain a predetermined volume of sample;
wherein the sampling device comprises a sampling portion that comprises a fibrous material or a foam material;
wherein the sampling device comprises a dry coating that includes an effective amount of a pH-adjusting reagent that, when contacted with a liquid reagent composition having a pH of about 6.8 or lower, changes the pH of the liquid reagent composition to 6.9 or higher;
wherein the liquid reagent composition comprises a luciferin;
contacting the predetermined volume of sample with both the dry coating comprising the pH-adjusting reagent and the liquid reagent composition in a container to form a reaction mixture; and
using a luminometer to detect light emitted from the reaction mixture;
wherein the container comprises a cuvette portion adapted to be operationally coupled to the luminometer.
2. The method of claim 1 , further comprising the step of agitating the sampling portion and the liquid reagent composition in the container.
3. The method of claim 1 , wherein the liquid reagent composition further comprises a luciferase enzyme.
4. The method of claim 1 , wherein contacting the sampling device comprising the sample with liquid reagent composition comprises contacting the sampling device with the liquid reagent composition at a temperature within a range of 10° C. and 35° C., inclusive.
5. The method of claim 1 wherein, after contacting the sampling device with liquid reagent composition, a steady-state amount of light is emitted from the composition in less than 20 seconds.