The invention relates to pipettes for use in liquid dispensing and concerns tip cones or tips used therein. Tips according to the invention are suitable for use, for example, when utmost cleanness is required.
Pipettes are provided with disposable tip cones or tips, which are fixed to the end of a pipette's suction channel and into which the liquid to be pipetted is drawn. The pursuit of utmost cleanness is often a reason to use individually packed tips.
A traditional solution for individual packages has been a vacuum-molded channel type bag, in which the tip lies on its side. The bag has a heat-sealed cover. The bags are packed in bulk containers, which are then sterilized by irradiation. The user opens the bag at the tip attachment end and holds the tip through the bag while fixing the tip to a pipette.
There are also trays available for tips. In this case, the tip has a widened top end and the tray has holes for suspending the tips thereby. Picking up tips from a tray is easy, especially for a multichannel pipette. In the manufacture of sterile tray packages, the entire tray, along with its tips, is placed inside a bag which is then sterilized by irradiation.
WO 97/39827 describes a device comprising a plurality of vessel-like casings each containing one tip. The casings are closed hermetically but can be opened at the top.
What has been invented now, is a pipette tip package, a combination of a pipette tip package and a tray, and a method of manufacturing a pipette tip package.
According to the invention, the pipette tip is placed in an enclosure with a closed bottom end and an open top end, such that the tip has its top end towards the top end of the enclosure. Then, the top ends of a plurality of separate enclosures are securely closed by fixing a joint lid thereto to form a multi-tip package. Such a unit can then be cut for individual packages. The lid can be fixed for example by heat sealing, gluing or by a friction joint. After the closing operation, the package can still be sterilized, particularly by irradiation.
The user opens the lid and inserts the end of a pipette's suction channel into the tip. The procedure is easy and, while being fixed in place, the tip is exposed as little as possible to contamination.
Tips are manufactured virtually always from a suitable plastic by injection molding. The enclosure is also most conveniently manufactured by injection molding. Production is feasible with automated production lines currently in service. Cleanness in production is easily ensured in the manufacture of tips according to the invention. The invention enables also loading a tray in such a way that sterility is easily maintained.
The tip may have an enlargement in its upper part, constituting a shoulder with the tip's outer surface. The enlargement may consist of longitudinal ribs present in the upper part of the tip. The enclosure may have an internal reduction, specifically a shoulder, which responds to that of the tip. Hence, in the process of fixing it to a pipette, the tip can be pressed against the internal reduction of the enclosure for a good sealing effect. For this purpose, the enclosure must naturally be sufficiently rigid for pressing the tip against it with an adequate force.
The enclosure may also have in its upper part an enlargement on its outer surface. This enables loading the enclosure on a tray, which has an aperture for placing the enclosure therein to be suspended by the enlargement.
Nevertheless, the lid of a multi-tip package can be opened, as necessary, even without cutting the lid. In this case, the unit can be placed on a tray with an aperture for each enclosure, The enclosures are arranged in a multi-tip package most conveniently in straight rows. Hence, the lid can be formed always between the rows with a cut, such as a perforation. This enables an easy opening of the lid, one row at a time. From the tray, tips are handy to pick up from a row for a multichannel pipette of a matching pitch.
The invention is of a particular benefit, specifically in the case of tray packages. The fabrication of sterile packages is easier than at present. The only components that have to be superclean are the tip, the interior of the enclosure, and the internal side of the lid. The enclosures can be manufactured in the immediate vicinity of tip production and possibly even concurrently with tips. After the enclosures are closed, the tips are protected from contaminations. There is no need of further protecting the product by a plastic bag, nor do the tips require a traditional perforated plate for shipping. Savings in material and labor are remarkable.
Less packaging material is needed and the size of shipped packages is smaller as the user need not be always supplied with a new tray along with the tips. There is no need to expose more tips from the tray than those required at a time, whereby the tips left in the tray remain absolutely clean.
According to the invention, it is easier than before to achieve the highly stringent requirements of certain applications, regarding the absence of nuclease and endotoxin.
The accompanying drawings constitute a part of the written description of the invention and relate to the detailed description of some embodiments of the invention presented hereinafter. In the drawings,
The tip package of
The tip user removes the lid, inserts the end of a pipette's suction channel into the package, whereby the tip has its shoulder 4 pressing against the tube's shoulder 6 and the tip is set firmly in position at the end of the pipette.
Both the tip 1 and the tube 2 are fabricated by injection molding. The tip is placed in the tube, and the thus obtained package is closed immediately, most preferably by heat sealing.
As shown in
According to
If desired, the tube 2 below the external shoulder 6 can be further provided with an annular groove for snap-fitting the lid 10 therein, thus providing a robust structure.
Number | Date | Country | Kind |
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20085988 | Oct 2008 | FI | national |