FR2671876A1 - Mixer apparatus for reactions on an immuno-haematology plate - Google Patents

Abstract

The device makes it possible to mix, simultaneously, several drops of blood and of reagents which are placed on various circular places on a plate, without risk of contamination from one mixture to another. It consists of an upper plate (1) carrying cylindrical mixer elements (2) having a rounded end, which is applied to another reaction plate (3), comprising circular reference marks (4) inside which the drops to be mixed are deposited beforehand. Guides (5, 6) consisting of a circular element (6) and of a rod (5) enable the 2 plates to be fitted together perfectly and limit the amplitude of the rotary movement to the exact area of each circular reference mark (4). The device according to the invention is particularly intended for the obtaining of blood groups on a plate.

Description

MIXER FOR RECTIONS ON
IMMUNO-HEMATOLOGY PLATE
The present invention relates to a device allowing the simultaneous mixing on a plate of blood drops and reagents, quickly and without risk of contamination.

 Many immuno-hematological reactions consist of bringing a drop of blood and a drop of reagent into a horizontal plate and then mixing them. The reaction is said to be positive or negative depending on whether or not agglutination occurs.

 The mixing of the drops is traditionally carried out using a mixing device (generally a simple glass or plastic rod held in the hand) whose hemispherical end avoids scratching the horizontal plate on which the drops have been deposited. . Between each mixture the end of the mixing device must be thoroughly cleaned and wiped to avoid contamination of the following drops. This is long and tedious since the number of mixing operations is high. For example, a determination of the blood group requires 8 mixes, therefore 10 determinations want d. ire to mixes! There is also a risk of contamination between the different drops by the mixing device if the latter is not properly cleaned each time, and a risk of contamination of the manipulator during cleaning operations.

 The device according to the invention makes it possible to remedy these drawbacks by simultaneously carrying out firstly all the operations of mixing reagents and blood, and, secondly all the operations of cleaning the mixing devices.

 It includes a horizontal plate, preferably transparent, on which several cylindrical mixing devices with a hemispherical end are fixed vertically = this is the mixing plate.

 The horizontal plate on which the drops to be mixed are deposited, or reaction plate, has circular marks traced opposite each mixing device, so that when the drops to be mixed will be placed inside these circular marks , they can all be simultaneously in contact with a mixing device.

The mixing operations will then be carried out simultaneously by imparting to the mixing plate a horizontal rotation movement of amplitude equal to the diameter of the circular marks. The cleaning of the mixing devices will be carried out by simultaneously immersing their ends in a flat-bottomed container, of appropriate size, containing a decontaminating solution.

A guide device will limit the horizontal rotation diameter, printed by the manipulator to the mixing plate, to the diameter of the circular marks inside which the drops of blood and reagent are mixed.

 This guiding device will also immediately ensure a complementarity of the 2 plates, that is to say the simultaneous and perfect contact of each mixing device with the center of each circular mark, when the mixing plate is superimposed to the reaction plate.

 It will consist either of a cylindrical well dug in the thickness of one of the plates, or of a raised ring fixed on one of the plates, and of a vertical rod fixed on the other plate in the axis of the well or the ring, of a length such that it enters the well or the ring when the mixing plate is placed on the reaction plate The respective diameters of the vertical rod and the cylindrical well or the 'ring are calculated according to the diameter that one wants to obtain for the mixed drop, that is, in practice that of the circular marks of the reaction plate.

To be effective, these guiding devices will be at least 2, located at each end of the plates. But we can conceive of having one at each angle of the plates, that is to say four, or even several around the entire periphery.

 Two handles were provided on the mixing plate to facilitate the positioning of this plate on the reaction plate, and to perform the rotational movement necessary for mixing the drops.

 On the reaction plate circular markers facilitate the deposition of the drops. These marks will be materialized either by circles affixed to the plate by a technique allowing them to resist washing operations, or by wells dug in the thickness of the plate.

 On the mixing plate, the mixing elements can either be fixed in the plate by a thread and a nut, or cast with the plate in a single block. In the first case, the elements can be made of stainless steel and screwed into the polystyrene plate. In the second case they can be like the plate, made of polystyrene, or other transparent synthetic material. The important thing is that the end of each mixing element is rounded in order to avoid friction forces, excessive crushing of the drops of blood, or scratching the reaction plate.

 A cleaning tank containing a decontaminating liquid will serve to immerse all the ends of the mixing elements when all the drops of blood and reagents have been mixed on the reaction plate This tank of dimensions slightly larger than the plates, will have the rectangular shape of the plates , and edges high enough to allow not only the cleaning of the mixing plate, but also the storage of the whole device, ie the 2 plates. The cleaning and therefore storage tank may be made of stainless steel or any other material resistant to the detergent solutions used to clean and decontaminate the mixing elements.

 When this bin is used to store the 2 plates, it can be closed with a lid adapted to its dimensions and made of the same material.

 The accompanying drawings illustrate the invention. An overall view (Fig 1) of the device shows the 2 plates in the position of use.

The upper mixing plate (1) carries the mixing elements (2).

The lower reaction plate (3) has circular marks (lit.

In the example shown, it roars in circles drawn by a process resistant to repeated washing and to detergents and disinfectants.

Inside these circular marks (4) will be deposited the drops of blood and reagents to be mixed.

 When the 2 plates are superimposed, the mixing plate (1) comes into contact with the reaction plate (3) via the mixing elements (2) which are each positioned within a circular reference (4). It then suffices to print on the mixing plate (1) a slight horizontal rotational movement so that the mixing elements (2) operate the mixing of the drops inside each circular mark (4).

 The guide devices, thanks to their 2 complementary elements (5-6), allow a perfect superposition of the 2 plates (1-3) so that each mixing element (2) is in contact with a circular reference (4). They also make it possible to ensure efficient rotation of the mixing plate (1), so that the entire surface delimited by a circular mark is traversed by a mixer element and finally they prevent the drops from mixing from one mark to the other. 'other.

 A detailed drawing (Fig 2) of a guide device shows that it consists of 2 elements: 1 circular element (6) and a rod (5), each appearing on a plate. In the example we have chosen to represent the circular element in the form of a ring (6) is fixed to the mixing plate (1) while the small rod (5) intended to penetrate inside the ring (6) is fixed on the reaction plate (3).

 The fact of superimposing the plates (1 of 3) makes it penetrate (5) into (6), and when a rotary movement is imparted to the mixing plate (1), the rod (5) limits the amplitude of the movement at the perimeter of the ring (6). This perimeter is calculated to correspond to that of the circular analysis marks (4) The drawing (fig 2) clearly illustrates the concomitant and identical movement of the guiding device and the mixing element on the reaction plate.

 In the example shown Ona shows 2 guide devices arranged at each end of the 2 plates.

 To allow easier use of the plates, two handles (7) are provided. These can be screwed into the plate (1) at each of its ends, or cast in the same material as the plate, for example made of polystyrene.

 So that the reaction plate (3) remains fixed on the work surface and is not entrained in the rotational movement of the mixing plate (1), 4 small feet are provided fixed to the four corners of the reaction plate (3 ). These feet can be like on our model simple rubber washers, but also any other natural or synthetic material having a slight adhesive power.

 The device we have chosen to represent is particularly intended for the production of blood groups.

 Knowing that a blood group requires 8 mixtures, it is convenient to number the reaction plate (3) from I to VIII in the width direction and from 1 to 10 in the length direction. For a group, row 1 of the marks I to VIII will be used. For 10 groups, use the 10 rows from 1 to 10.

 To adapt to the needs of each laboratory, it is conceivable to make plates of 5 or 6 rows only of VIII markers instead of 10, but for handling problems and size we cannot exceed fifteen rows .

 In a preferred embodiment, the circular marks will have an internal diameter of 2 cm and will be spaced 1 cm apart. We will leave on the periphery a free area of 3 cm. Thus for a device making it possible to carry out 10 groups, the plates will measure 35 cm long and 29 cm wide. The mixing elements (2) will have a length of 2 cm.

Claims (4)

 1) Device for simultaneously mixing on a plate drops of blood and reagents, characterized in that it comprises - an upper horizontal mixing plate (1) on which are vertically fixed mixing elements (2) with hemispherical end. - a lower horizontal reaction plate (3) comprising circular marks (4) arranged opposite each mixing element (2), so that during the superposition of the 2 plates, the drops to be mixed, deposited inside the pins (4) will simultaneously be in contact with the end of a mixing element (2). - optionally a flat bottom tray for cleaning the plates with a decontaminating solution and subsequent storage of the plates.  2) Device according to claim (1) characterized in that it comprises at least two systems for guiding and limiting the diameter of horizontal rotation printed on the mixing plate (1), to the diameter of the circular marks (4) at the inside of which the mixing of the drops takes place, each comprising a circular element (6) fixed or hollowed out on one of the plates, and a vertical rod (5) fixed on the other plate, penetrating into the circular element (6) when the 2 plates (1) and (3) are in contact.  3) Device according to claim (2) characterized in that the circular element (6) is either a well dug in the thickness of the plate or a raised ring fixed on the plate, of the same diameter and the same depth that said well.  4) Device according to any one of claims 1 to 3, characterized in that it comprises grip and manipulation handles fixed on the upper mixing plate.