METHOD AND DEVICE FOR DETECTING THE PRESENCE OF A SINGLE TARGET NUCLEIC ACID IN SAMPLES

1 . A method for detecting, for each of a plurality of sample portions, whether the sample portion includes at least one molecule of a target nucleic acid, said method comprising:

for each individual sample of a plurality of samples, loading at least one sample portion of said individual sample into at least one respective sample chamber of a plurality of sample chambers, each said sample portion comprising at least a part of said individual sample,

whereby for each individual sample portion, if said sample portion contains at least a single molecule of said target nucleic acid, said sample portion would attain a detectable concentration of said target nucleic acid within a portion of said sample portion after a single round of amplification;

subjecting said sample portions to at least a first amplification step; and then

for each of a plurality of said sample portions, determining whether said sample portion contains at least one molecule of said target nucleic acid.

2 . A method as recited in claim 1 , wherein said first amplification step is a homogeneous amplification step.

3 . A method as recited in claim 1 , wherein said first amplification step is a thermocycle step

4 . A method as recited in claim 1 , wherein if a 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 amplification step.

5 . A method as recited in claim 1 , wherein said determining whether said sample portion contains at least one molecule of said target nucleic acid is performed by carrying out a procedure which generates signals having magnitude which is higher where said detectable concentration is present than where said detectable concentration is not present.

6 . A method as recited in claim 5 , wherein said procedure comprises detecting fluorescence from fluor-labeled materials.

7 . A method as recited in claim 5 , wherein said procedure comprises detecting at least one chemical property which changes upon hybridization.

8 . A method as recited in claim 5 , wherein said procedure comprises evaluating at least one property selected from among the group consisting of agglutination, turbidity, phosphorescence, light scattering, light absorbance, fluorescence energy transfer, fluorescence quenching, fluorescence dequenching, time-delayed fluorescence, chemiluminescence and calorimetric evaluation.

9 . A method as recited in claim 1 , wherein said sample chamber comprises at least a portion of an inside of a microcapillary device, and wherein said peaks are generated by detecting regions within said microcapillary device in which said detectable concentration is present.

10 . A method as recited in claim 1 , wherein each of said sample chambers has a volume of about 1 picoliter or less.

11 . A method as recited in claim 1 , wherein each of said sample chambers has a volume in the range of from about 1 picoliter to about 1 microliter.

12 . A method as recited in claim 1 , wherein each of said sample chambers has a volume of about 10 picoliters or less.

13 . A method as recited in claim 1 , wherein each of said sample chambers has a volume of about 100 picoliters.

14 . A method as recited in claim 1 , wherein each of said sample chambers has a volume of about 1 nanoliter.

15 . A method as recited in claim 1 , wherein each of said sample chambers has a volume of 10 nanoliters or less.

16 . A method as recited in claim 1 , wherein each of said sample chambers has a volume of about 10 nanoliters.

17 . A method as recited in claim 1 , wherein each of said sample chambers has at least one dimension of 2 mm or less.

18 . A method as recited in claim 1 , wherein each of said sample chambers has at least one dimension of 1 mm or less.

19 . A method as recited in claim 1 , wherein each of said sample chambers has at least one dimension of 100 microns or less.

20 . A method as recited in claim 1 , wherein each of said sample chambers has at least one dimension of 20 microns or less.

21 . A method as recited in claim 1 , wherein each of said sample chambers has at least one dimension of a few microns or less.

22 . A method as recited in claim 1 , wherein each of said sample portions has a volume of about 1 picoliter or less.

23 . A method as recited in claim 1 , wherein each of said sample portions has a volume in the range of from about 1 picoliter to about 1 microliter.

24 . A method as recited in claim 1 , wherein each of said sample portions has a volume of about 10 picoliters or less.

25 . A method as recited in claim 1 , wherein each of said sample portions has a volume which is nanoliter-sized.

26 . A method as recited in claim 1 , wherein each of said sample portions has a volume of about 1 nanoliter or less.

27 . A method as recited in claim 1 , wherein each of said sample portions has a volume of about 10 nanoliters or less.

28 . A method as recited in claim 1 , wherein each of said sample portions has a volume of about 100 nanoliters or less.

29 . A method as recited in claim 1 , wherein each of said sample portions has a volume of about 1 microliter or less.

30 . A method as recited in claim 1 , wherein each of said sample portions is confined in at least one dimension by opposing barriers separated by about 2 mm or less.

31 . A method as recited in claim 1 , wherein each of said sample portions is confined in at least one dimension by opposing barriers separated by about 1 mm or less.

32 . A method as recited in claim 1 , wherein each of said sample portions is confined in at least one dimension by opposing barriers separated by about 500 microns or less.

33 . A method as recited in claim 1 , wherein each of said sample portions is confined in at least one dimension by opposing barriers separated by about 100 microns or less.

34 . A method as recited in claim 1 , wherein each of said sample portions is confined in at least one dimension by opposing barriers separated by about 20 microns or less.

35 . A method as recited in claim 1 , wherein each of said sample portions is confined in at least one dimension by opposing barriers separated by a few microns or less.

36 . A method as recited in claim 1 , wherein each said sample chamber comprises at least a portion of an inside of a microcapillary device.

37 . A method as recited in claim 36 , wherein said microcapillary device has an internal volume of about 100 nanoliters or less.

38 . A method as recited in claim 36 , wherein said microcapillary device has an internal volume of about 10 nanoliters or less.

39 . A method as recited in claim 36 , wherein said microcapillary device has an internal volume of about 1 nanoliter or less.

40 . A method as recited in claim 36 , wherein each of said sample portions has a volume of about 60 nanoliters or less.

41 . A method as recited in claim 36 , wherein each of said sample portions has a volume of about 100 nanoliters or less.

42 . A method as recited in claim 36 , wherein said microcapillary device has an inner diameter in the range of from 20 micrometers to 75 micrometers.

43 . A method as recited in claim 36 , wherein said microcapillary device has an inner diameter of about 100 micrometers.

44 . A method as recited in claim 36 , wherein said microcapillary device has an inner diameter of about 100 micrometers or less.

45 . A method as recited in claim 36 , wherein said microcapillary device has an inner diameter of about 500 micrometers or less.

46 . A method as recited in claim 36 , wherein said microcapillary device has a length in the range of from about 1 mm to about 100 mm.

47 . A method as recited in claim 36 , wherein said microcapillary device has a length of about 4 cm.

48 . A method as recited in claim 36 , wherein said microcapillary device comprises at least two surfaces spaced from each other by about 20 micrometers or less.

49 . A method as recited in claim 1 , wherein each said sample chamber comprises at least a part of a porous sample structure.

50 . A method as recited in claim 49 , wherein at least one of said porous sample structures comprises a plurality of pores, each of said pores having a first end and a second end, said first end of each of said pores being open.

51 . A method as recited in claim 49 , wherein at least one of said porous sample structures comprises a plurality of pores, each of said pores having a first end and a second end, said first and second ends of each of said pores being open.

52 . A method as recited in claim 49 , wherein at least one of said porous sample structures comprises a plurality of pores, each of said pores having a first end and a second end, said first end of each of said pores being hydrophobic.

53 . A method as recited in claim 49 , wherein said first porous sample structure comprises a plurality of pores, each of said pores having a hydrophilic interior.

54 . A method as recited in claim 49 , wherein at least one of said porous sample structures comprises a plurality of pores, an interior of each of said pores being hydrophilic, and an exposed surface of said porous sample structure being hydrophobic.

55 . A method as recited in claim 49 , wherein at least one of said porous sample structures comprises at least one structure selected from the group consisting of microchannel arrays, structures having pores formed therein, metal screens, plastic screens, glass screens, ceramic screens, cellulosic screens, polymeric screens, metal sieves, plastic sieves, glass sieves, ceramic sieves, cellulosic sieves and polymeric sieves.

56 . A method as recited in claim 49 , wherein said porous sample structures are positioned in a microfluidic device which comprises a plurality of porous sample structures.

57 . A method as recited in claim 49 , wherein each of said sample portions has an internal volume of about 1 picoliter or less.

58 . A method as recited in claim 49 , wherein each of said sample portions has an internal volume of about 10 picoliters.

59 . A method as recited in claim 49 , wherein each of said sample portions has an internal volume of about 10 nanoliters or less.

60 . A method as recited in claim 49 , wherein each of said sample portions has an internal volume of about 100 nanoliters or less.

61 . A method as recited in claim 49 , wherein each of said sample portions has an internal volume in the range of from about 100 nanoliters to about 1 microliter.

62 . A method as recited in claim 49 , wherein said porous sample structure has an internal volume of about 1 picoliter or less.

63 . A method as recited in claim 49 , wherein said porous sample structure has an internal volume in the range of from about 1 picoliter to about 1 microliter.

64 . A method as recited in claim 49 , wherein said porous sample structure has an internal volume of about 1 nanoliter or less.

65 . A method as recited in claim 49 , wherein said porous sample structure has an internal volume of about 10 nanoliters or less.

66 . A method as recited in claim 49 , wherein said porous sample structure has an internal volume of about 100 nanoliters or less.

67 . A method as recited in claim 49 , wherein said porous sample structure has an internal volume of about 1 microliter or less.

68 . A method as recited in claim 49 , wherein said porous sample structure has an internal volume of about 1 micron.

69 . A method as recited in claim 1 , wherein each of said sample chambers contains at least one amplification targeting reagent.