Container for carrying out and monitoring biological processes
A thermal cycling method and device is disclosed. The device comprises a sample chamber whose temperature can be rapidly and accurately modulated over a range of temperatures needed to carry out a number of biological procedures, such as the DNA polymerase chain reaction. Biological samples are placed in containers each comprising a reservoir and a reaction portion, wherein the reaction portion has a small volume. The small volume reaction portion permits the rapid and accurate temperature modulation. With an optically transmissible reaction portion, DNA amplification may be monitored by fluorescence during PCR.
1. A system comprising
a plurality of containers, said containers comprising walls composed of an optically transparent material and defining a volume having a first and second dimension, wherein the first dimension is less than the second dimension and the ratio of volume to external surface area of the container is less than 1 mm;
a continuously rotatable carousel for holding said plurality of containers and sequentially moving the plurality of containers, one-by-one to a monitoring position;
a source of forced air for heating and cooling said plurality of containers; and
means for performing fluorescent detection on a sample contained within one of said plurality of containers and held at said monitoring position, while each sample is simultaneously subjected to rapid thermal cycling.
2. A system according to claim 1 , further comprising a stepper motor and drive shaft for rotating said rotatable carousel, and wherein said fluorescent detection means comprise a fluorimeter assembly for illuminating and detecting fluorescence of a sample held within the container.
3. A system according to claim 2 , wherein the containers comprise capillary tubes having a closed end, an open end and an inner diameter of less than 1 mm.
4. A system according to claim 3 , wherein the fluorimeter assembly illuminates and detects fluorescence along an axis essentially parallel to the longitudinal axis of the container to establish an epifluorescent excitation and detection pathway.
5. A system according to claim 4 , wherein the detection pathway is focused at the closed end tip of the capillary tube.
6. A system according to claim 5 , wherein the tip of the capillary tube is positioned at the focal point of the detection pathway during monitoring.
7. The system of claim 3 further comprising a structure that seals the open end of the capillary tubes.
8. A system according to claim 1 wherein the container further comprises a biological sample, wherein the sample comprises nucleic acids, components for amplification of the nucleic acids using a polymerase chain reaction, and a fluorescent probe.
9. A system according to claim 8 , wherein the fluorescent probe comprises a fluorophore bound to an oligonucleotide.
10. A system according to claim 9 , wherein the fluorescent probe comprises a pair of oligonucleotide probes that hybridize to adjacent regions of said nucleic acids, wherein one of said pair of probes is labeled with an acceptor fluorophore and the other probe is labeled with a donor fluorophore of a fluorescent energy transfer pair.
11. A system for conducting and monitoring rapid PCR on multiple samples, said system comprising a plurality of containers, wherein said containers comprise:
a capillary tube portion which is closed at one end, open at the other end and comprises an optically transparent portion; and
a funnel-shaped portion, having a sample receiving port and a sample transfer port, said funnel-shaped portion being joined to the open end of the capillary tube portion, so that the sample transfer port of the funnel-shaped portion and the open end of the vessel are in alignment, wherein said container holds less than 1 ml of the sample;
a removable structure that seals the sample receiving port of the funnel-shaped portion;
a continuously rotatable carousel for holding said plurality of containers and sequentially moving the plurality of containers, one-by-one to a monitoring position; and
a fluorimeter assembly for illuminating and detecting fluorescence of a sample held within the container at said monitoring position while all samples are being simultaneously subjected to rapid thermal cycling, wherein hot and cool forced air is used as the thermal transfer agent to conduct the rapid thermal cycling.
12. A system according to claim 11 , wherein the capillary tubes have an inner diameter of less than 1 mm.
13. The system of claim 11 wherein the capillary tube portion wall is about 0.1 mm thick, and the material comprising the capillary tube portion has a thermal conductivity of about 20 to about 35 in accordance with the formula:
(
cal
cm
cm
2
s
degree
C
.
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×
10
4
.
14. The system of claim 13 , wherein the tip of the capillary tube is positioned at the focal point of the detection pathway during illumination and fluorescence detection of a sample held within the container.
15. The system of claim 11 wherein the structure is a stopper.