Thermocycler

Abstract

A thermocycler having a base fitted with a temperature-controlled receiving segment for reaction vials is provided. The thermocycler further includes a top, which can be moved into its operational position above the receiving segment and a hermetic seal or wall configured in the top in its operational position that extends between the top and the base thereby sealing both the top and the base.

Description

BACKGROUND OF THE INVENTION

The present invention relates to a thermocycler. The term “thermocycler” usually denotes apparatus allowing PCR (reactions). PCR is a well-established procedure known to the expert, this abbreviation being well understood to denote using polymerase on a test sample to amplify the target nucleic acids contained therein.

In particular the present invention relates to thermocyclers allowing measuring in real time the increase over time of the amplified products. Such thermocyclers comprise a base in which is constituted an appropriate, temperature controlled receiving segment receiving reaction vials subjected to PCR. Moreover such an apparatus comprises a top displaceable from an open position into an operational position above the receiving segment. This top is fitted with a test optics which in the operational configuration is situated opposite the receiving segment and can detect optical signals in the reaction vials.

Accurate temperature control of the reaction vials is intrinsically critical in PCR. This applies especially to real time procedures, such procedures almost inevitably being quantified and already minute deviations from the reference temperature sequence possibly entailing spurious results. Accordingly slight temperature fluctuations due to extraneous air effects must be excluded. The same considerations apply to stray light entering laterally the light path between the test optics and the receiving segment and possibly degrading measurement.

Accordingly it is the objective of the present invention to create a thermocycler allowing PCR to take place while free from extraneous factors, in particular in the real time mode, in simpler and more reliable manner.

BRIEF SUMMARY OF THE INVENTION

The thermocycler of the present invention is fitted with a hermetic wall running in a closed loop around the receiving segment and extending between the top and the base thereby sealing the top and the base.

The wall of the present invention effectively allows screening the PCR receiving segment against extraneous air effects for instance.

In principle the wall of the present invention also may be fitted into conventional thermocyclers. Preferably however it shall be employed for real-time thermocyclers. In that case the hermetic wall is also light-tight and in the top's operational configuration surrounds both the receiving segment in the base and the test optics in the top, thereby providing a light path and a reaction space protected against external interference.

In theory the wall might be kept in storage as a separate component and would be mounted on the base prior to PCR and illustratively would engage in sealing manner by its upper open end the top when this top has been lowered into its operational position.

More appropriately however the wall is used as a component joined to the thermocycler. Conceivably the wall as a rigid component might be projecting from the base or the top. In that case however there would be danger of degrading handling. Preferably for sealing therefore the wall shall project by the length required from the top respectively the base upward and downward only during PCR. In cases not requiring the wall, it might be retracted in its entirety into the top or the base.

In another preferred embodiment of the present invention, the wall length is adjustable. In an especially preferred embodiment mode, this feature illustratively can be attained in that the wall is in the form of a bellows affixed by one of its open ends for instance in a closed loop to the top and is able to be lowered at the other free open end by an appropriate adjustment device down on the base when the top is in its operational position. To assure optimal sealing, one or more closed-loop silicone seals or the like may be used at the free wall end or at the preferably employed bellows. It is understood that such seals also may be used in other cases at the two open wall ends when a separate component is involved.

Illustratively the bellows may be driven by a separate element at the top, for instance an adjusting wheel or the like. If drive elements already are present at the top to implement top adjustment or locking the top in position, the adjustable wall also may be adjusted in that manner. In that case the drive elements may be synchronized in a manner that when the top is displaced and locked into its operational position, the drive element used for such actuations also may be used to displace the wall of the present invention between the top and the base.

It should be borne in mind that the above discussion is merely didactic. Obviously too the wall may be configured in or on the base. Provided the wall is adjustable in length, it need not mandatorily be a bellows. Other applicable designs include longitudinally adjustable ones such as lamellas and telescopes.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic cross-section view of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 schematically shows a cross-section of a thermocycler 10 comprising a base 11 fitted with a receiving segment 12 receiving reaction vials. Heater elements 13 and 14, in particular Peltier elements, are used to control the temperature of the receiving segment 12. The diagrammatic recesses 15 receive the reaction vials to be temperature controlled. Typically thermocycler receiving segments are designed to receive microtitration trays (not shown).

Furthermore, the thermocycler 10 comprises a top 18, shown in its operational position, which in said position rests on protrusions 19 configured on the base 11. A downward looking test optics 20 is configured at the top 18 and is fitted with several test apertures 21 associated with the recesses 15. A particular amplification taking place in a reaction vial can always be optically measured by said test optics 20.

A wall 22 in the form of a bellows is configured between the top 18 and the base 11 and surrounds the test optics 20 and the receiving segment 12. The wall 22 is affixed by one end to the top 18. The length of the wall 22 can be adjusted by an adjustment device 25. This adjustment device 25 comprises adjusting elements 26 that, by means of a mechanism 27 not shown in further detail and upon actuation of a setting element 28, can be displaced in the direction of the arrow 29 toward or away from the top 18. By their lower ends, the adjusting elements 26 act on a looping seal 30 configured on the free edge of the wall 22, said seal cross-sectionally flaring downward to constitute effective protection against stray light. When the setting element 28 is actuated, the wall can be lowered as needed from the top 18 toward the base 11 to effect sealing or to be moved into a rest position near the top 18.

Claims

1. A thermocycler comprising:

a base fitted with a temperature-controlled receiving segment for reaction vials;

a top which can be moved into an operational position above the receiving segment; and

a hermetic wall configured in the operational position of the top to surround the receiving segment while extending between the top and the base thereby sealing the top and the base.

2. The thermocycler as claimed in claim 1, wherein a test optics is opposite the receiving segment when the top is in its operational position.

3. The thermocycler as claimed in claim 1, wherein the hermetic wall is light-tight.

4. The thermocycler as claimed in claim 1, wherein the hermetic wall is adjustable in length.

5. The thermocycler as claimed in claim 1, wherein the hermetic wall is mounted by its upper open end to the top.

6. The thermocycler as claimed in claim 1, wherein the top is fitted with a setting element to allow adjustment to the length of the hermetic wall.

7. The thermocycler as claimed in claim 1, wherein the hermetic wall is a bellows.

8. The thermocycler as claimed in claim 1, wherein one or more closed loop seals are constituted at the free end of the hermetic wall.