METHOD AND DEVICE FOR DETECTING THE PRESENCE OF A SINGLE TARGET NUCLEIC ACID IN A SAMPLE
A method comprising depositing a sample portion in a sample retaining means, and forcing a curable fluid across an exposed surface of the sample retaining means, thereby displacing excess first sample from the exposed surface without displacing the sample from the sample retaining means. Also, a method comprising depositing a sample portion in a sample retaining means, removing excess sample from an exposed surface of the sample retaining means, and depositing a curable fluid on the exposed surface. Also, a microfluidic device comprising a sample chamber, a first sample portion in the sample chamber, and a curable fluid and/or a cured fluid positioned on an exposed surface of a sample retaining means.
1 . A method for detecting whether at least one molecule of a target nucleic acid is present in a first sample portion, said method comprising:
depositing at least a first sample portion in a sample retaining means, said first sample portion comprising at least a portion of a first sample;
forcing a curable fluid across an exposed surface of said sample retaining means, thereby displacing any excess first sample from said exposed surface without displacing said sample from said sample retaining means.
2 . A method as recited in claim 1 , wherein as said curable fluid is forced across said exposed surface, a layer of said curable fluid is deposited on said exposed surface and coats a top of said first sample portion.
3 . A method as recited in claim 2 , wherein said method further comprises curing said curable fluid to form a seal for the first sample portion retained in said sample retaining means, whereby said first sample portion is isolated from other sample portions and from excess first sample.
4 . A method as recited in claim 2 , wherein said curable fluid is immiscible with said first sample
5 . A method as recited in claim 1 , wherein if said first sample portion contains at least a single molecule of said target nucleic acid, said first sample portion would attain a detectable concentration of said target nucleic acid within a portion of said first sample chamber after a single round of amplification.
6 . A method as recited in claim 5 , wherein said method further comprises:
subjecting said first sample portion in said first sample chamber to at least a first amplification step; and then
determining whether said first sample portion contains at least one molecule of said target nucleic acid.
7 . A method for detecting whether at least one molecule of a target nucleic acid is present in a first sample portion, said method comprising:
depositing at least a first sample portion in a sample retaining means, said first sample portion comprising at least a portion of a first sample;
removing excess first sample from said exposed surface; and
depositing at least a first curable fluid on said exposed surface of said sample retaining means.
8 . A method as recited in claim 7 , wherein said method further comprises curing said curable fluid to form a seal for the first sample portion retained in said sample retaining means, whereby said first sample portion is isolated from other sample portions and from excess first sample.
9 . A method as recited in claim 8 , wherein said curing said curable fluid is conducted immediately after said removing excess first sample from said exposed surface.
10 . A method as recited in claim 7 , wherein said curable fluid is immiscible with said first sample
11 . A method as recited in claim 7 , wherein if said first sample portion contains at least a single molecule of said target nucleic acid, said first sample portion would attain a detectable concentration of said target nucleic acid within a portion of said first sample chamber after a single round of amplification.
12 . A method as recited in claim 11 , wherein said method further comprises:
subjecting said first sample portion in said first sample chamber to at least a first amplification step; and then
determining whether said first sample portion contains at least one molecule of said target nucleic acid.
13 . A microfluidic device comprising:
a first sample chamber; and
a first sample portion, said first sample portion being positioned in said first sample chamber; and
a curable fluid positioned on an exposed surface of said sample retaining means, said curable fluid covering at least said first sample portion.
14 . A microfluidic device as recited in claim 13 , wherein said curable fluid is immiscible with said first sample
15 . A microfluidic device as recited in claim 13 , wherein if said first sample portion contains at least a single molecule of said target nucleic acid, said first sample portion would attain a detectable concentration of said target nucleic acid within a portion of said first sample chamber after a single round of amplification.
16 . A microfluidic device as recited in claim 13 , wherein said microfluidic device further comprises at least one amplification targeting reagent positioned in said first sample portion.
17 . A microfluidic device comprising:
a first sample chamber; and
a first sample portion, said first sample portion being positioned in said first sample chamber; and
a cured fluid positioned on an exposed surface of said sample retaining means, said cured fluid covering at least said first sample portion.
18 . A microfluidic device as recited in claim 17 , wherein said cured fluid forms a seal for the first sample portion retained in said sample retaining means, whereby said first sample portion is isolated from other sample portions and from excess first sample.
19 . A microfluidic device as recited in claim 17 , wherein if said first sample portion contains at least a single molecule of said target nucleic acid, said first sample portion would attain a detectable concentration of said target nucleic acid within a portion of said first sample chamber after a single round of amplification.
20 . A microfluidic device as recited in claim 17 , wherein said microfluidic device further comprises at least one amplification targeting reagent positioned in said first sample portion.