FI65386C - SAEKERHETSANORDNING FOER TILLSLUTNING AV PROVROER - Google Patents

Description

1 65386

The present invention relates to a safety device for closing a test tube, comprising a stopper of rubber, flexible plastic material or other similar resilient material fitted inside the mouth of the test tube, through which liquid is added to or removed from the test tube, and the top surface is formed mainly conically tapering.

Bottles and tubes are used for various purposes, which are tightly closed, e.g. with a rubber or plastic stopper. If it is desired to add or withdraw liquids to or from these bottles or tubes without removing the stopper, the stopper is usually pierced with a sharp needle attached to the syringe. When the needle is removed, the rubber stopper is still still tii-15 vis, with the elastic force of the rubber closing the hole made in the stopper by the needle. The same happens with plugs made of suitable plastic grades. However, the stoppers used in the past have been such that they could not be perforated with plastic pipette tips or glass capillaries, which are most often used today for dispensing various samples or reagents.

The object of the present invention is to obviate the above-mentioned drawbacks, and the test tube closure apparatus according to the invention is mainly characterized in that the top surface of the stopper is formed as a conically tapering part guiding the pipette tip or capillary towards the bottom of the plug. a channel is formed through which the pipette tip or capillary can be inserted, but each channel is tightly closed by the resilient force when the pipette tip or capillary is removed therefrom. In addition, the conically tapering upper space of the closure plug is adapted to be closed at the top by a cap.

Thus, the flexible stopper of the test tube has a pre-made channel for the tip or capillary of the pipette, which opens when the tip or capillary is inserted through the stopper at a certain point. For example, once the sample has been transferred from the tip or capillary to the test tube, the tip or capillary may be left in the channel in the stopper, if desired, retained by the resilient force of the stopper.

In addition to adding an additional sample or reagent to the test tube through the stopper, the desired amount of sample or reagent can be taken with a pipette or capillary. Such a safety test tube has several applications and can be used as such in connection with a single laboratory test or as part of a system or apparatus as an integral or detachable part thereof as a single tube or as a matrix comprising several tubes. In the matrix, the closure plugs of the safety test tubes can be separate or connected to each other at the same distances as the test tubes themselves are.

The invention will become more apparent from the following description and the accompanying drawings, in which Figures 1 and 2 show two embodiments of the invention in a side sectional view.

The material of the plug 2 is rubber, a flexible plastic material or other similar resilient material. The bottom surface of the stopper 2 is most suitably planar. Instead, the stopper 2 on its upper surface is formed to taper substantially conically towards the bottom of the stopper, so that this part 3 acts as a guide part 25 for the tip or capillary of the pipette. A channel 4 is formed between the tip of the conical guide part 3 and the bottom surface of the closure plug 2. The channel M may be an open channel all the way or some part thereof may be closed by a thin film which can be easily perforated by the pipette tip or capillary. When the plug 2 30 is fitted inside the mouth of the test tube 1, the elastic force of the channel 4 is tightly held when the outer diameter of the plug 2 relative to the inner diameter of the test tube 1 is determined to be suitable for the purpose.

The test tube 1 provided with a stopper 2 is suitable for use, e.g., in the determination of blood hemoglobin. In this case, the test tube 1 contains K-cyanide (e.g. a buffered mixture of K-cyanide and - terracyanide solution in a certain ratio) and the test tube 1 is closed with a resilient stopper 2. To determine the hemoglobin in the test tubes 1 containing K-cyanide, the blood sample is transferred a capillary blood sample of the desired size.

5 When using toxic K-cyanide as a reagent in the determination of hemoglobin, it is of paramount importance that the reagent be safely pre-packaged in test tubes under factory conditions that meet occupational safety regulations. If laboratory personnel pipette K-cyanide into test tubes and then add a blood sample to it and measure the reaction mixture thus obtained by transferring it further to the photometer cuvette, the personnel are at constant risk of acquiring K-cyanide poisoning.

When the K-cyanide is packed at the factory in a test tube 1, which 15 is closed by a stopper 2, there is no risk of poisoning to the laboratory personnel through the stopper 2. The use of the security spout 1 increases the work safety so that the tip inserted for pipetting the sample through the stopper 2 of the test tube 1 can be left in place in the channel 4 of the stopper 2. The lower end of the tip dipped in the sample then remains inside the test tube 1 and the part of the tip left outside the test tube 1 is clean on the outside. The tip thus left in place in the stopper 2 of the test tube 1 cannot pose, for example, a risk of hepatitis or other infection to laboratory personnel. After the measurement, the safety test tube 1 with its contents together with the tip is easy to dispose of as a single unit.

In addition to increasing safety at work, the safety test tube 1 also improves accuracy. When the capillary is inserted through the stopper 2 of the test tube 1, the lower part of the capillary 30 passes through the channel 4 of the narrow stopper 2 and at the same time the channel 4 wipes the outer surface of the lower part of the capillary free of sample droplets. Some of these sample droplets on the outer surface of the capillary accumulate in the conical space 3 of the upper surface of the plug 2 as droplets. In this case, the droplets wiped off the outer surface of the lower part 35 of the capillary do not drip into the reagent in the test tube 1 or are not flushed by the reagent when the test tube L is shaken. In the case of “65386 small sample volumes, an additional sample on the outside of the pipette tip or capillary could cause several tens of percent error in sample delivery. The safety device according to Figure 1 has a cap separate from the additional plug.

of the tube 1 in figure 2 the mouth is closed with sealing plugs 7, which is shown in the corresponding channel 9 · Sulkutulpas-sa 8 above 7 of the conical portion is still in the cylindrical-ing part 6 so that after the pipetting of the sample koeput-10 ken, the one blind plugs 7 of the upper side of the conical the space can be closed with a cap 10.

In Figure 2, the closure plug 7 and the cap 10 are in one piece and are adapted to be connected by a narrow, flexible and flexible base 11.

It is also possible for the cap to be attached to the test tube itself with a small flexible base, in which case the test tube and the cap are made in one go, e.g. by injection molding from a suitable plastic.

When the top of the stopper is closed with a cap, liquid droplets remaining in the top 20 and wiped e.g. from the outer surface of the pipette tip do not pose a hazard to workers or the environment during further processing of the tube such as shaking, incubation, photometric measurement, etc. -in-25 due to the risk of infection.

Claims (2)

5 65386 A safety device for closing a test tube (1), comprising a stopper (2, 7) arranged inside the mouth of a test tube of rubber, flexible plastic material or other similar resilient material, through which liquid is added to or removed from the test tube (1) and the stopper (2) , 7) the upper surface is formed as a substantially conical tapered part (3, 3) towards the bottom of the stopper, characterized in that the tip and the stopper (2, 7) of the guide part (3, 8) guiding the tip (5) or capillary (6) of this pipette a channel (4, 9) is formed between the bottom surface through which the pipette tip (5) or capillary (6) can be pushed, but each channel (4, 9) is tightly closed by the elastic force when the pipette tip (5) or capillary (6) ) is removed therefrom, and that the conically tapering upper space of the closure plug (2, 7) of the test tube (11) is adapted to be closed at its top by a cap (10, 12). Safety device according to Claim 1, characterized in that the plug (2, 7) and the cap (10) are integral and are adapted to be connected by a narrow, flexible and flexible base (11).