Reaction well for assay device
This disclosure relates to an apparatus for simultaneously filling a plurality of sample chambers. In one aspect, the apparatus comprises a common fluid source and a plurality of independent, continuous fluidic pathways. Each independent, continuous fluidic pathway comprises a sample chamber and a pneumatic compartment. The sample chamber is connected to the common fluid source, and the pneumatic compartment is connected to the sample chamber. The sample chamber comprises, in part, an assay chamber. The assay chamber comprises a monolithic substrate and a plug. In some embodiments, the assay chamber contains a magnetic mixing element. In some embodiments, the assay chamber is a double tapered chamber. In some embodiments, a ratio of a volume of the sample chamber to a volume of the pneumatic compartment is substantially equivalent for each fluidic pathway of the plurality of fluidic pathways.
1. A method of detecting amplified nucleic acid, the method comprising:
providing an apparatus comprising:
(i) a common fluid source containing a fluid sample comprising a nucleic acid; and
(ii) a plurality of independent, continuous fluidic pathways, each independent, continuous fluidic pathway comprising:
(A) a sample chamber connected to the common fluid source, said sample chamber having a fluid volume, wherein the sample chamber comprises:
(1) an assay chamber having an assay chamber volume, wherein the assay chamber comprises a first bounding surface formed in a monolithic substrate and a second bounding surface formed by a transparent plug, the plug comprising a body and a cap, the body protruding into the monolithic substrate at a depth, wherein the cap of the plug forms the second bounding surface of the assay chamber, and
(2) an entry conduit connecting the common fluid source to the assay chamber; and
(B) a pneumatic compartment connected to the sample chamber, said pneumatic compartment having a pneumatic volume;
wherein excluding the connection between the sample chamber and the common fluid source, each fluidic pathway is a closed system, and wherein a ratio of the fluid volume to the pneumatic volume is substantially equivalent for each fluidic pathway of the plurality of fluidic pathways,
applying a supply pressure to the common fluid source whereby the fluid sample flows into the sample chamber of each fluidic pathway to substantially fill the sample chamber,
heating each sample chamber of the plurality of fluidic pathways, thereby amplifying one or more nucleic acids in the fluid sample; and
visually detecting amplification of nucleic acid through the transparent plug.
2. The method of claim 1 , wherein the supply pressure is ramping.
3. The method of claim 1 , further comprising sealing the fluidic pathway, after substantially filling and before heating the sample chamber of each fluidic pathway.
4. The method of claim 3 , wherein sealing the fluidic pathway comprises applying a heating element to the entry conduit of each fluidic pathway to seal the entry conduit.
5. The method of claim 4 , wherein the assay chamber further comprises a third bounding surface formed by a film, wherein the first bounding surface, second bounding surface, and third bounding surface together enclose the assay chamber volume.
6. The method of claim 5 , wherein the third bounding surface is formed by a first film adhered to a surface of at least a portion of the apparatus, wherein the first film forms one wall of the entry conduit of each fluidic pathway.
7. The method of claim 6 , wherein the apparatus further comprises a second film adhered to the first film, wherein the second film has a higher melting temperature than the first film and surface of the apparatus.
8. The method of claim 7 , wherein, when the heating element is applied, the first film and the surface of the apparatus melt but the second film does not.
9. The method of claim 1 , wherein amplifying one or more nucleic acids in the fluid sample uses LAMP.
10. The method of claim 1 , wherein an internal cavity formed in the cap of the plug contains one or more dried reagents.