CHEMICAL REACTION APPARATUS

Abstract: A chemical reaction apparatus is disclosed which com­ prises endless travelling belt(s) (2) disposed to support in place a multiplicity of juxtaposed reaction containers (Z) hav­ ing the axes thereof fail in a plane inclined from the horizontal plane and adapted to travel in a substantially horizontal direc­ tion perpendicular to the axes of the reaction containers (Z), endless retaining belts (1) disposed adjacently and not conti­ guously to the aforementioned travelling belts (Z) and pro­ vided with a multiplicity of teeth projecting up as regularly spaced by fixed intervals slightly greater than the diameters of the reaction containers (Z) so as to enable the reaction con­ tainers (Z) accommodated in the intervening spaces between the teeth to be held in fixed positions in an arrayed pattern, a base (3) adapted to support in place the bottoms of the afore­ mentioned reaction containers (Z) rotated about their axes in an inclined state by the aforementioned travelling belts (2) and the aforementioned retaining belts (Z), and a drive mechanism for intermittently driving the aforementioned retaining belts (1) and thereby effecting pitch sending of the aforementioned reaction containers (Z).

Description: Background of the Invention Field of the Invention: This invention relates to a novel reaction apparatus for enabling a chemical reaction to be carried out simply and efficiently, and more particularly to an apparatus most suitable for automatically processing various steps of a chemical reaction. For example, this apparatus is not only usable in a wide range of chemical industries including biochemistry but also adoptable for efficiently processing various tests in biochemical and microbiochemical studies and in clinical diagnosis. Description of the Prior Art: Chemical reactions are classified under a large number of types. Generally in any chemical reaction, the conditions such as temperature, pressure, time, light, and stirring under which the reaction is carried out have very large effects upon the results of the reaction. Among these factors, stirring has a conspicuous effect on the chemical reaction involved. Chemical reaction apparatuses are provided, therefore, with various stirring means adapted specifically to suit their purposes. For a large chemical reaction apparatus, a stirring device normally in the form of a propeller is set inside a tank. Then, optimal reaction conditions are established theoretically and empirically by the selection of the shape of the propeller, the variation of the rotation speed of the propeller, etc. The incorporation of such a stirring device as a propeller, however, becomes increasingly difficult as the reaction container diminishes in size. In the culture of a microorganism, the operation of stirring is simplified by collectively shaking the reaction containers. The conventional stirring method described in the preceding paragraph, however, has a disadvantage such that the uniformity of stirring decreases in proportion as the reaction containers diminish in size. In recent years, the practice of diagnosing various diseases by using various chemical reactions, particularly immunochemical reactions, has been finding growing acceptance. The specimen for this diagnosis is mainly the blood of a given patient. Since this amount of blood is limited and must be used for various tests, the amount of blood available for each test would become quite small. Consequently, the reaction containers used for individual test items are liable to come in smaller sizes. Since no effective means of stirring had been proposed for use in such small chemical reaction containers, it was inevitably necessary to let the reaction containers stand without any stirring until the reactions initiated therein proceeded amply. Thus there had been a disadvantage such that the total reaction time took several hours' to several days'. Despite this disadvantage immunochemical reaction using a radioisotope or an enzyme is frequently resorted to the diagnosis of cancer and many other diseases. This is because this reaction decisively excels other methods of diagnosis in both sensitivity and reliability. The presence or absence of a disease and the condition of the disease are determined by accurate measurement of the contents of substances in the blood which serve as criteria for diagnosis. Thus, increasing significance has come to be placed on the accuracy and the reliability of the measurement in recent years. At present for such diagnosis the use of immobilized antibodies is widely accepted. As the solid phase for immobilizing antibody, finely divided particles or beads made of plastic or glass are used. At times, the lower part of inner surface of the reaction container may be utilized as the solid phase. Generally in a chemical reaction, the components which take part in the reaction are dissolved in a homogeneous solution and are allowed to move freely therein. The chemical reaction is accelerated when the solution is stirred or otherwise agitated so that the components therein will be given a better chance of mutual collision. If any of the components taking part in the chemical reaction is immobilized onto a solid surface, the mutual collision of the components is greatly restrained and consequently the speed of the chemical reaction notably decreases. In such a case, stirring is used as a means of promoting the progress of the reaction. A solution, however, has not yet been found to overcome the aforementioned disadvantages which occur particularly when using a multiplicity of reaction containers each of a small volume. The inventors continued their search for a solution to the problems encountered by the conventional technique as described in the preceding paragraph. They have consequently found that particularly in the case of small reaction containers in which stirring apparatus such as a propeller cannot be inserted, the inclined rotation of the containers themselves brings about faster reaction and highly accurate results. The present invention has been accomplished on the basis of this knowledge of the inventors'. The inventors have already devised several inclined rotation apparatuses. One of the apparatuses (type A) comprises a multiplicity ("n" in number) of rollers possessed of a fixed diameter approximating the diameter of cylindrical reaction containers and juxtaposed parallelly as inclined at a fixed angle, so that the reaction containers (a total of "n - 1" in number) placed one each on every two adjacent rollers will be rotated by the rotation of the rollers in one direction at a fixed speed (Japanese Patent Application Laid-open SHO 58(1983)-36631, US Patent 4482636). Another of the apparatuses (type B) comprises two parallelled chains each provided thereon with a multiplicity of freely rotatable equally spaced rollers such that every two adjacent rollers on one of the two chains will support the reaction containers near the mouth and every two adjacent rollers at the corresponding position on the other chain will support them near the bottom, and as the result, the multiplicity of reaction containers will be held in an inclined position in much the same manner as attained by the rollers of the apparatus of type A described above (Japanese Patent Application Laid-open SHO 58(1983)-36631, US Patent 4482636). This apparatus is enabled to impart a desired rotation to the reaction containers by moving in one direction an endless belt adapted to hold down the reaction containers. It is otherwise enabled to effect intermittent delivery of the reaction containers by causing the chains to be driven with at fixed intervals of time, whereby each reaction container will stop at the exact position of their preceding containers. Yet another of the apparatuses (type C) comprises a multiplicity of cylinders inclined and rotated as inclined at a fixed speed so that the reaction containers inserted one each in the interior of the cylinders will be automatically rotated. (Japanese Patent Application Laid-open SHO 58(1983)-61469, US Patent 4479720). Generally, in the performance of a chemical reaction, there must be interposed various steps such as, for example, fractionation, addition of specimen and reagents, washing of reaction containers, and sampling of reaction mixtures for the determination of the degree of progress of reaction. Of the apparatuses described above, that of type A is simple mechanism where the rotation speed can be highly controlled, but it has a disadvantage of hampering incorporation therein of a device permitting further improvement of the mechanism to the semi-automatic or full-automatic level. On the other hand the apparatus of type B is capable of advancing the reaction containers intermittently at a fixed pitch. Since this apparatus has the reaction containers held down by the belt draped thereon, however, it does not permit ready incorporation therein of a manual or automatic hopper unit capable of supplying reaction containers at the outset of the operation of the apparatus or a unit for release of reaction containers. It also entails the disadvantage that it permits no easy incorporation therein of a mechanism which enables a reaction container located at a desired position to be raised to an upright posture and, therefore, proves convenient for the automation of such steps as rinsing interior of the container and replacement of reaction mixture. The apparatus of type C is convenient for solely manual operation similar to the apparatus of type A. When this apparatus is desired to be adapted so as to permit the aforementioned intermittent advancement of reaction containers similar to type B, the adaptation inevitably entails complication of mechanism as by the incorporation of a turntable system wherein a plurality of cylindrical holders are equally spaced in a circumference having as its center the central axis perpendicularly intersecting an inclined disk and are each adapted to be rotated about their respective axes perpendicularly intersecting the inclined disk, so that the reaction containers in the cylindrical holders will be intermittently advanced by a fixed pitch each time the inclined disk is rotated by one pitch over a fixed time. In the adapted apparatus, when a given step is desired to be carried out with the reaction container held upright, this apparatus necessitates further incorporation of a complicated mechanism because the reaction container cannot be held upright unless it is removed from the cylindrical holder. FR-A-2 512 207 discloses a chemical reaction apparatus comprising a plurality of cylindrical reaction containers (A) and at least one endless travelling means in the form of a transport chain (101) comprising rollers (117). Furthermore, the known arrangement comprises a belt (109) being pressed by rollers (106) in order to rotate the reaction containers. Furthermore, driving means are provided for the travelling means and for the means for maintaining the cylindrical reaction containers at an angle and finally, a plate (116) of the known apparatus forms a base on a frame of the apparatus for supporting the bottoms of the reaction containers. FR-A-2 512 207 corresponds to JP-A-58-36 631 which has been discussed in the introductory part of the present application as apparatus "type A". Concerning this known apparatus, it has to be outlined that generally, in the performance of a chemical reaction, there must be interposed various steps, for example, fractionation, addition of specimen and reagents, washing of reaction containers and sampling of reaction mixtures for the determination of the degree of progress of reaction. The apparatus known from FR-A-2 512 207 is a simple mechanism where the rotational speed can be highly controlled, but it suffers from the drawback of hampering incorporation therein of a device permitting further improvement of the mechansim to the semi-automatic or full-automatic level. Furthermore, FR-A-2 514 510 corresponds to the "type C" apparatus as discussed on page 6 of the present application, comprising a multiplicity of cylinders inclined and rotated as inclined at a fixed speed so that the reaction containers inserted on each in the interior of the cylinders are automatically rotated. This kind of apparatus is convenient for solely manual operation similar to the apparatus of type A corresponding to the generic prior art document. When this apparatus is desired to be adapted so as to permit the intermittent advancement of reaction containers, the adaption inevitably entails complication for the mechanism as by the incorporation of a turntable system wherein a plurality of cylindrical holders are equally spaced in a circumference having as its centre the central axis perpendicularly intersecting an inclined disc and are each adapted to be rotated about the respective axis perpendicularly intersecting the inclined disc so that the reaction containers in the cylindrical holders will be intermittently advanced by a fixed pitch each time the inclined disc is rotated by one pitch over a fixed time. In the adapted apparatus when a given step is desired to be carried out with the reaction container held upright, this apparatus necessitates further incorporation of a complicated mechanism because the reaction container cannot be held upright unless it is removed from the cylindrical holder. Summary of the Invention An object of this invention is to provide a chemical reaction apparatus which is simpler in mechanism than any of the conventional apparatuses of the class and which permits a given chemical reaction to be continuously performed automatically on a multiplicity of dissimilar samples by combining devices necessary for various steps of the process involved such as addition of specimens, rinsing the inside of their reaction containers, and sampling of reaction mixtures and interlocking these devices in accordance with a preset program. The chemical reaction apparatus of this invention is constructed according to claim 1. Further details and embodiments are disclosed in the dependent claims. Brief Description of the Drawings Fig. 1 is a perspective view illustrating a typical chemical reaction apparatus embodying the present invention. Fig. 2 (A) is a front view of a belt driving mechanism for the apparatus of Fig. 1. Fig. 2 (B) is a top view of the belt driving mechanism for the apparatus of Fig. 1 Fig. 3 is a cross section of the apparatus of Fig. 1 as taken along a plane perpendicularly intersecting the direction of the travel of the belt. Fig. 4 illustrates a raising mechanism for setting upright a reaction container. Fig. 4 (I) is a diagram illustrating the raising mechanism in the standby state in an apparatus using two travelling belts. Fig. 4 (II) is a diagram illustrating the raising mechanism already operated to set upright the reaction container in Fig. 4 (I). Fig. 4 (III) is a diagram illustrating the raising mechanism in the standby state in an apparatus using one travelling belt. Fig. 4 (IV) is a diagram illustrating the raising mechanism already operated to set upright the reaction container in Fig. 4 (III). Fig. 4 (V) is a top view illustrating the reaction container set upright by the raising mechanism. Fig. 5 is a front view of the configuration of the apparatus corresponding to the process of the immunoreaction. Detailed Description of the Invention Now, the functions fulfilled by the individual technical means which make up the chemical reaction apparatus of the present invention will be described below. The inventor has ascertained that when reaction containers are placed on a travelling belt and stoppers disposed like the teeth of a comb on separate retaining belts so as to prevent the reaction containers from being carried away by the belt in motion, the reaction containers are rotated about their own axes at a peripheral speed equalling the speed of the travelling belt without slipping off. Even in such a simple setup as described above, the reaction containers are rotated without producing the slightest slip and this setup functions effectively without the use of any complicated mechanism such as belts used in previous invention (type B) which draped the reaction containers and advanced in a direction opposite the direction of the travel of the belt provided for carrying the reaction containers. The certainty of the rotation of the reaction containers in this setup has been confirmed by visually counting the number of revolutions of the reaction containers with the aid of marks placed one each on the reaction containers. The results of this test are shown in Table 1. As shown above, the number of revolutions of the reaction containers is inversely proportional to their diameters. Furthermore, when the diameter of a reaction container (A) is multiplied by π and by the number of revolutions and divided by 10, it will be equal, or if not, be very close to the distance the belt covers per minutes. The number of revolutions varies slightly among the reaction containers as shown in Table 1. It has been found that this is ascribable to the fact that the diameters of the reaction containers slightly vary. In other words, this slight variance in the number of revolutions is not the result of the reaction containers slipping from the belt. When desired, the numbers can be made uniform by utilizing individual reaction containers of exactly the same diameters. Superficially, the fact that the reaction containers are rotated without slipping from the belt when in motion may seem to be a matter of everyday observation. However the adoption of this principle has led to notable simplification of apparatus. It has enabled mechanisms such as those for setting upright a reaction container to be incorporated in the apparatus at a desired position, so that such steps as introduction of specimens in reaction containers, rinsing of used reaction containers, and sampling of reaction mixtures, which had to be conventionally carried out while the reaction containers were held in the inclined state, to be carried out while the reaction containers are set upright. When such steps are performed with the reaction containers set upright, one or more reaction containers can be set upright all at once by synchronously actuating raising mechanisms located at desired positions. Thus, nozzles and other devices intended to perform the aforementioned steps may be disposed at desired positions on a horizontal bar disposed parallelly to the direction of travel of the belt and adapted to move vertically and, by the vertical movement of the bar, may be synchronously reciprocated in the vertical direction. During this vertical reciprocation, the nozzles and other devices are allowed to fulfil their own functions. The chemical reaction apparatus of the present invention has a simpler rotational mechanism than any other conventional apparatus as described above. Thus it permits the incorporation of a simple mechanism to advance the reaction containers sequentially at a fixed pitch. Also as it is designed without any means such as a belt to suppress the reaction containers onto the apparatus itself, it has enabled the containers to be set upright at locations selected at will for performance of various steps of process by a simple mechanism adapted to raise a reaction container with an upward push exerted from below or an upward pull exerted from above. Owing to the construction described above, the present invention can manifest the following prominent effects which none of the conventional techniques could. 1. A multiplicity of small reaction containers can be easily and efficiently rotated simultaneously about their axes as held in the inclined state. Since all the reaction containers are slowly rotated at a fixed speed as inclined at a fixed angle, the stirring of their contents will be neither accelerated nor decelerated. Therefore the chemical reaction is enabled to proceed very uniformly and smoothly. The effect of the inclined rotation method adopted in the present invention on immunoreaction, as compared with the stationary method is shown below in Table 2 and Table 4, and its effect on the propagation of rhinovirus is shown in Table 3. 2. Since the chemical reaction apparatus is capable of conveying a multiplicity of reaction containers collectively while keeping them rotated in the inclined state, it permits certain chemical reaction to be continuously carried out. 3. All the steps of process can be carried out with the reaction containers held in the inclined state. Where they are judged to be carried out more advantageously with the reaction containers held upright, devices adapted to set a reaction container upright can be disposed at freely selected position in the apparatus. Rinsing of the reaction containers to be performed at the position indicated by "b" in the Fig. 5, for example, can be accomplished more advantageously when the reaction containers are held in the upright state for the rinsing solution can be completely removed and the incident of the solution overflowing can be reduced. 4. When the chemical reaction apparatus of this invention is interlocked with such a measuring instrument as the photometer, it is enabled to monitor the progress of reaction and evaluate the outcome of the reaction automatically. 5. When the chemical reaction apparatus is provided with an optical or electromagnetic reading device, it is enabled to read out the information written on the reaction containers, i.e. the information regarding test item and reactivity of reagent. Thus, otherwise possible confusion of test items and troublesome display of input data on the individual reaction containers can be eliminated. 6. By the incorporation of the functions mentioned above, the chemical reaction apparatus constitutes itself a setup befitting the performance of such chemical reactions as immunochemical reaction and enzyme reaction. Owing further to the automation of the operations involved, a number of dissimilar reactions can be continuously carried out qucikly and accurately. Description of the Preferred Embodiment Now, a typical chemical reaction apparatus embodying the present invention will be described below. This is just one example embodiment of the present invention and, therefore, allows for various alterations of design. First, the apparatus will be described with reference to the accompanying drawings. Fig. 1 portrays the chemical reaction apparatus in its entirety and Fig. 2 (A) and Fig. 2 (B) are explanatory diagrams illustrating the drive mechanism for the belt of the apparatus. Reaction containers Z are supported in place by a set of two toothed retaining belts 1, a set of two travelling belts 2, and a base 3 adapted to prevent the reaction containers Z from slipping down along the angle of inclination. These reaction containers Z are rotated about their axes by the belts 2 which are advanced by the rotation of wheels 4 (A, A') fixed on a shaft 6 connected to a motor 5 which is fitted with a speed reducer. Wheels 9 (A, A') which are fixed on a shaft 8 connected to a motor 7 fitted with a speed reducer normally remain at rest to keep the reaction containers Z at their fixed positions. When the reaction containers Z are to be advanced at a fixed pitch, the motor 7 is set to forward the belts 1 and move the reaction containers Z by one pitch to their next positions. The distance over which the belts 1 are advanced at a pitch is fixed because the motor 7 is controlled and stopped when a detector such as photosensor 10 detects the positions of the teeth of a comb. Since wheels 4 (B, B') are not fixed on the shaft 8, they are rotated by the motion of the belts 2 produced in consequence of the rotation of the wheels 4 (A, A'). Since wheels 9 (B, B') are not fixed on the shaft 6, they are rotated by the motion of the belts 1 produced in consequence of the rotation of the wheels 9 (A, A'). The mechanism described above is intended to cause a multiplicity of cylindrical reaction containers of same size which are juxtaposed with their mouth up and their axes falling in a plane inclined at a fixed angle from the horizontal plane, rotated about their axes at a fixed rotational speed as retained in the positions at the angle of inclination both indicated above so as to allow the required chemical reaction to proceed within. To ensure economization of reagents and specimens and enhancement of reaction efficiency, the angle of inclination of the reaction containers so held in place by the aforementioned mechanism may fall somewhere in the range of 0 degree (horizon) to 45 degrees, so that the reaction containers Z will not spill their contents. Generally, satisfactory results are obtained by selecting the angle in the range of 5 to 20 degrees (Table 4). The rotational speed of the reaction containers Z is desired to fall in the range 10 to 150 rpm, i.e. rotation per minute. If the rotational speed is lower than 10 rpm, the stirring of the reaction mixtures in the reaction containers does not occur effectively. Conversely if it is higher than 150 rpm, the stirring does not occur efficiently because high molecular substances are inactivated by the mechanical impact or the liquids are rotated in conjunction with the reaction containers Z instead of flowing down the walls of the containers (Table 4). The endless travelling belts 2 are so constructed that they will be continuously advanced at an equal speed by a drive device in one horizontal direction perpendicular to the axes of the reaction containers Z while supporting thereon the reaction containers Z. They are only required to remain in contact with the lower sides of the reaction containers Z and to rotate the reaction containers Z about their axes by virtue of the resultant friction. These belts 2 may be made of such material having high coefficiency of friction as polyurethane or chloroprene. The speed of the belts 2 can be freely adjusted by means of a motor fitted with a speed reducer and a pulley. In this case, the travelling speed of the belts 2 can be stabilized further by adopting timing belts as the belts 2 and timing pulleys specifically adapted for such belts as the pulleys. The other endless retaining belts 1 which are disposed parallelly and not contiguously to the aforementioned travelling belts, provided thereon with a multiplicity of teeth projecting up as spaced at a fixed interval slightly greater than the diameter of the reaction containers, and adapted to retain the reaction containers at fixed relative positions are only required to comprise belt webs made of such material as polyurethane or chloroprene and teeth planted on the belt webs as spaced at fixed intervals enough to admit the reaction containers Z therein and allow them to rotate freely therein. The teeth may be made of such material as Teflon (tetrafluoroethylene), or polypropylene. To avoid obstructing the rotation of the reaction containers Z, the retaining belts are disposed at a position slightly lower than the travelling belts 2. The material of the teeth is desired to have a friction coefficient lower than the friction coefficient of the travelling belts 2. The number of teeth can be selected so as to agree with the convenience of operation, this number is desired to fall in the range of 20 to 200. In this case, the chemical reaction apparatus is enabled to acquire a simpler and more reliable mechanism by adopting, as retaining system, those timing belts which have teeth planted along the outer boundaries thereof. The base 3 serving to support the bottoms of the reaction containers Z fulfils its function sufficiently by keeping the reaction containers Z from slipping down. It may be made of a metallic or a plastic material, having low coefficiency of friction. The drive device adapted to advance intermittently the retaining belts 1 at fixed intervals is installed for the purpose of feeding the reaction containers at a fixed pitch. The two retaining belts 1 are disposed one each along the mouth and the bottom of the reaction containers Z. By being synchronously moved, these retaining belts 1 enable the reaction containers Z placed thereon to be moved at a fixed pitch in a juxtaposed state. The time invervals with which the reaction containers Z are automatically advanced at a fixed pitch can be freely selected. Fig. 3 is a cross section of the apparatus of Fig. 1 as taken along a plane perpendicularly intersecting the direction of the travel of the belt. The reaction containers Z are supported in place by the set of two toothed retaining belts 1, the set of two travelling belts, and the base 3 disposed so as to keep the reaction containers Z from slipping down. They are rotated by the travelling belts which are driven by the rotation of the wheels 4 (A, A') fixed to the shaft 6 connected to the motor 5 fitted with the speed reducer. The angle of inclination of the reaction containers Z is adjusted by turning a screw 12 fitted to a frame 11. Fig. 4 is an explanatory diagram illustrating a mechanism for setting upright the inclined reaction containers at stated positions in the apparatus. Fig. 4 (I) represents an embodiment using two travelling belts. A holder 13 is joined through an arm 14 integrally to a rotary plate 16 which is connected to a shaft 15. A holder 17 is integrally joined to an arm 19 which is connected to a metal member 18. The metal member 18 is adapted to be freely rotated about the shaft 15. The arm 19 is pulled by a spring 20 and retained at a fixed position shown in Fig. 4 (I) by a stopper 21. In consequence of the rotation of the shaft 15 in the clockwise direction, the holder 13 rises in conjunction with a claw 22 through the medium of the rotary plate 16 and the arm 14 to push up the reaction container Z. The holder 13, during the rise, cooperates with the holder 17 and the claw 22 to pinch the reaction container Z and then continues to rise. When the reaction container Z is brought to the upright position as shown in Fig. 4 (II), the shaft 15 discontinues its rotation. Then, when the shaft 15 is rotated in the counterclockwise direction, the reaction container Z is returned to its original state as shown in Fig. 4 (I). Fig. 4 (III) and Fig. 4 (IV) represent an embodiment using one travelling belt 2. In the mechanism illustrated, the holder 13 pushes up the upper end of the reaction container Z and the holder 17 and the claw 22 pinch the reaction container Z and set it upright. Fig. 4 (V) illustrates the reaction container Z as pinched between the holders 13, 17. Fig. 5 is a front view of the apparatus laid so as to correspond to the process of the immunoreaction. A reaction container feeder 23 which accommodates therein reaction containers Z containing an enzyme labeled antibody therein and having the antibody immobilized to the inner walls thereof feeds out the reaction containers Z sequentially. When the first reaction container Z reaches the position "a", the raising device of Fig. 4 is actuated to set the first reaction container Z upright. The specimen injector which has drawn the specimen from the specimen turntable injects a fixed amount of the specimen together with a buffer solution into the reaction container Z. Then, the raising device is returned to its normal position and, consequently, the reaction container Z is rotated about its axis on the belts 2 and advanced toward the right. As the reaction container Z is advanced the immunoreaction occurs inside the reaction container Z. By the retaining belts 1, the subsequent reaction containers Z are successively moved at fixed time intervals toward the right, each undergoing the same steps of raising and injection. When the first reaction container Z reaches the position "b", the raising device located at the position "b" is actuated to set the first reaction container upright once again. The rinsing device empties the reaction container Z of the spent reaction mixture by suction. Then, it injects the rinsing liquid to cleanse the interior. The steps of injecting and sucking out the rinsing liquid are alternately repeated until the reaction container Z is thoroughly cleaned. Subsequently, the substrate solution for enzyme is injected by the dispensing device into the reaction container Z, and the raising device at the position "b" is returned to its normal position. The reaction container Z is then moved to the position "c". During this period, the enzyme reaction occurs inside the reaction container Z. At the position "c", the raising device is actuated to set the reaction container Z upright, so as to make the next process easy. The next process is carried out to determine the result by conveying and inserting the reaction container manually or mechanically into the spectrophotometer. The raising device at the position "c" returns to the normal position after the reaction container is removed. The position "b" and "c" are determined by reaction time and the pitch. The injection device for introducing the reagent into the reaction container is preferred to possess precision equivalent to the precision expected of fine analysis such as radioimmunoassay and to be capable of exactly separating a fixed amount of reagent exactly and introducing the reagent so separated into the reaction container. Where the specimen or the reagent is preferred to be diluted, the so-called diluting dispenser can be used which is capable of effecting the required dilution with a proper amount of diluent. For general use, any of the dispensing devices can be adopted in its unmodified form. Optionally, two or more such dispensing devices may be used at separated positions. The rinsing device for cleaning inside of the reaction container is desired to comprise, a combination of two cylinder type dispensers, one for removal and the other for injection by suction, or a combination of a dispenser using a water pump for introduction and a timer and a solenoid valve for control of flow volume with a device for effecting removal by suction under a vacuum are available. When the reaction containers are tightly sealed before use, the chemical reaction apparatus is preferred to incorporate an opening device for removing the seals from the reaction containers at the position from the feeder 23 to "a". As the measuring device for testing the reaction mixture in the reaction container for optical density, a spectrophotometer or a fluorophotometer can be utilized. The device so adopted may be of the flow type or discrete type. (Test Example) Tests were carried out with chemical reaction apparatuses embodying the present invention. The results are shown in Table 2 and Table 3. Table 2 shows the effect brought about by the use of the inclined rotation technique in the enzyme immunoassay for carcinoembryonic antigen (CEA). Test tubes with inner diameter of 12 mm, each containing a polystyrene bead 6 mm in diameter having an anti-CEA antibody immobilized thereon, 0.1 ml of specimen containing CEA of concentration of 10 ng/ml, and 0.4 ml of an enzyme labelled anti-CEA antibody solution, were left undergo immunoreaction at 25°C for 20 minutes at an angle of 90 degrees (upright) and a rotational speed of 0 r.p.m. (standing at rest) and at an angle of 10 degrees and rotation speeds of 30 and 240 r.p.m. To check the amount of the enzyme labelled antibody bound through CEA to the immobilized antibody, the enzyme labelled antibody which had failed to be bound was removed by rinsing. Then, the residue, with hydrogen peroxide as the substrate for the enzyme and ortho-phenylenediamine as a chromogen added thereto, was subjected to enzyme reaction under the same conditions for 10 minutes. Since peroxidase was used as the enzyme, it activated hydrogen peroxide and caused coloration of the ortho-phenylenediamine. In the table, the numerical values stated under "intensity of coloration" represent relative magnitudes, setting the intensity found when the reaction container was set upright and still as 100. It can be noted that 30 r.p.m. and 240 r.p.m. rotations enhanced the reaction 3.1 and 1.6 times respectively compared with when the reaction containers were set upright without any rotation. Table 3 shows the effect of the inclined rotation on the propagation of rhinovirus. In a plastic test tube (16 x 125 mm), 3 ml of Eagle Basal medium, containing 10% bovine fetal serum and having Ohio Hela cells suspended therein at a concentration of 1 x 10⁶ cells per ml, was subjected to rotary culture at 37°C for three days on an apparatus having an inclination of 10 degrees and a rotational speed of 30 r.p.m. From the resultant culture broth, the supernatant was removed and discarded. The residue of the culture broth, with 0.5 ml of Eagle Basal medium containing rhinovirus type 3 suspended at a concentration of 10 5.0 of 50% tissue culture infectious dose (TCID₅₀) added thereto, was subjected to rotary culture for one hour. The residue, with 2.5 ml of the same medium added thereto, was similarly subjected to rotary culture for three days. The supernatant consequently formed were gathered and tested for virus potency, TCID₅₀, by the method proposed by H. L. Torney et al., Antimicrobial Agents and Chemotherapy 22,635-638 (1982). In a plastic Roux flask (25 cm²), Ohio Hela cells inoculated at a concentration of 3 x 10⁶ cells per ml were left undergoing stationary culture for three days. The resultant culture broth, with the medium substituted with 0.5 ml of a medium containing rhinovirus type 3 suspended at a concentration of 10 5.0 TCID₅₀, was subjected to stationary culture for one hour. The culture broth, with 9.5 ml of the same medium further added thereto, was left undergoing stationary culture for three days. The supernatant consequently formed were gathered and tested for virus potency, TCID₅₀, by following the procedure described above. As indicated in the table, the propagation of virus by rotary culture was more than 10 times as effective as that by stationary culture. (Test Example) Table 4 shows the effects of the angle of inclination and rotation speed on reaction. The table given above compares the effect of inclined rotation on the enzyme immunoassay for ∝-fetoprotein (AFP). Cylindrical reaction containers having an inner diameter of 9 mm, each containing anti-AFP antibody immobilized on the inner surface near the bottom, 0.05 ml of specimen containing AFP at a concentration of 20 ng/ml and 0.20 ml of an enzyme labelled anti-AFP antibody solution, were set at varying angles of inclination, 90 degrees (upright state), 60 degrees, 30 degrees, and 10 degrees and rotated at varying speeds 0 (absence of rotation), 5, 30, 60, 120, and 240 r.p.m. to effect immunochemical reaction at 25°C for 20 minutes. To check the amount of the enzyme labelled antibody bound through AFP to the immobilized antibody, the enzyme labelled antibody which had failed to be bound was removed by rinsing. The residue, with hydrogen peroxide as the substrate for the enzyme and ortho-phenylenediamine as a chromogen added thereto, was left undergoing enzyme reaction for 10 minutes under the same conditions. Since peroxidase was used as the enzyme, it activated the hydrogen peroxide and caused coloration of ortho-phenylenediamine. The numerical values given in the table represent relative magnitudes setting the intensity of coloration obtained when the reaction containers were set upright and still as 100. In all the reaction conditions used herein, the coloration occurred with the highest intensity when the containers were inclined 10 to 30 degrees and rotated at speed ranging from 30 to 120 r.p.m. These specific conditions enhanced the reaction about 4 times as compared to when the reaction containers were set upright and still. It was also found that excessive rotation rather impeded than enhanced reaction. This disadvantage of the excessive rotation may be logically explained by a postulate that, during the immunoreaction, high molecular substances are inactivated by mechanical impact and the efficiency of this reaction is consequently degraded.

Claims: A chemical reaction apparatus comprising: a plurality of cylindrical reaction containers (Z) at least one endless travelling means (2) for supporting thereon said plurality of reaction containers (Z) arranged in parallel and rotating them; driving means (4A, A', 5, 6) for advancing said at least one endless travelling means (2) at a constant speed in one horizontal direction; means for maintaining said cylindrical reaction containers (Z) on said at least one travelling means (2) at an angle inclined with respect to a horizontal plane; and a base (3) on a frame adjacent said at least one endless travelling means (2) for supporting the bottoms of said reaction containers (Z) being characterized in that said travelling means take the form of at least one endless travelling belt (2), that separate endless retaining belts (1) are disposed on either side of said at least one travelling belt (2), said retaining belts (1) being disposed parallel to and not contiguously to said at least one travelling belt (2), each retaining belt (1) being provided thereon with a multiplicity of teeth projecting up at fixed, spaced intervals slightly greater than the diameter of said reaction containers (Z), and adapted to retain said reaction containers (Z) at fixed relative positions, the base portions of the retaining belt teeth being positioned below and the upwardly projecting portions of the retaining belt teeth above the surface of the travelling belt (2), and that drive means (7, 8, 9A, A') are provided for advancing said retaining belts (1) intermittently over fixed intervals of space. A chemical reaction apparatus according to claim 1, being characterized by at least one raising device (13 to 22) for supporting one after another of said reaction containers (Z) by the lower sides thereof and setting the reaction containers (Z) upright with the mouths thereof held upwardly. A chemical reaction apparatus according to claim 1 or 2, further characterized by an injection device for introducing a reagent into said reaction containers (Z) with said reaction containers (Z) at said angle of inclination or in an upright state. A chemical reaction apparatus according to one of claims 1 to 3, further characterized by a rinsing device. A chemical reaction apparatus according to anyone of claims 1 to 4, further characterized by an opening device for removing seals from said reaction containers (Z), with said reaction containers at said angle of inclinations or in an upright state, when said reaction containers (Z) are tightly sealed. A chemical reaction apparatus according to anyone of claims 1 to 5, further characterized by a sampling device for drawing samples of reaction mixtures from said reaction containers (Z) with said reaction containers (Z) at said angle of inclination, or in an upright state. A chemical reaction apparatus according to anyone of claims 1 to 6, further characterized by a measuring device for testing reaction mixtures in said reaction containers for optical density.

Inventors: MOCHIDA, EI
Applicants: MOCHIDA PHARMACEUTICAL CO., LTD.
Application year: 1985
Main classification: G01N35
IPC codes: G01N35, B01J19, B01L11