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. An apparatus, comprising:
a container with an opening and a cuvette portion that is adapted to be operationally coupled to a luminometer;
a liquid reagent composition comprising luciferin, wherein the liquid reagent composition is disposed in a closed compartment, wherein the pH of the liquid reagent composition is about 6.8 or lower; and
a sampling device having a sampling portion;
wherein the sampling portion is adapted to acquire and releasably retain a sample;
wherein the sampling portion comprises a fibrous 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 the liquid reagent composition, changes the pH of the liquid reagent composition to 6.9 or higher.
2. The apparatus of claim 1 , wherein the liquid reagent composition further comprises a luciferase enzyme.
3. The apparatus of claim 1 , wherein the sampling portion is adapted to obtain a predetermined volume of liquid.
4. The apparatus of claim 1 , wherein at least a portion of the coating is disposed on the sampling portion of the sampling device.
5. The apparatus of claim 1 , wherein the pH-adjusting reagent comprises a water-soluble reagent.
6. The apparatus of claim 1 , wherein the pH-adjusting reagent comprises a buffer component selected from the group consisting of N-[2-hydroxyethyl] piperazine-N′-[2-ethanesulfonic acid] (HEPES), N-[tris(hydroxymethyl)methyl]glycine (TRICINE), and combinations thereof.
7. The apparatus of claim 1 , wherein the coating further comprises an effective amount of a cell extractant.
8. The apparatus of claim 1 , wherein the liquid reagent composition further comprises a luciferase enzyme that comprises a recombinant luciferase enzyme.
9. The apparatus of claim 1 , wherein the liquid reagent composition further comprises a luciferase enzyme that consists essentially of a recombinant luciferase enzyme.
10. The apparatus of claim 1 , wherein the coating does not comprise an effective amount of a buffer component comprising phosphate.
11. The apparatus of claim 1 , wherein the sampling device is adapted to be contacted with the liquid reagent composition such that after contacting the sampling device with the liquid reagent composition a substantially steady state amount of light is emitted from the composition in less than 20 seconds.