HIGH-PRECISION CALORIMETER

Abstract: Appts. consists of a constant temperature bath (2) filled with water (80), a heater (8) a stirrer (12), and a detecting vessel (14) filled with any one of liquid paraffin, silicon oil or perfluorocarbon (82). The detecting vessel (14) has a calorimetric unit inside, which is contained in an aluminium pole (24) and consists of a reference heater (16) and a sample passage pipe (18) sandwiched by a thermocouple (20). A number of samples, such as serum and red blood cells, are supplied via supply pipes (32), heated up to a constant bath temperature, and mixed together in a mixer (30). The amount of heat generated due to the mixing is then measured by the thermocouple (20).

Description: FIELD OF THE INVENTION The present invention relates to a precision calorimeter comprising a temperature-controlled bath container having a heater and an agitator, a detection bath container disposed in said temperature-controlled bath container, said detection bath container having a detection unit which is placed in the detection bath the detection unit comprising a thermocouple for detecting a quantity of heat due to a thermal reaction of a sample. Specially such a calorimeter is used in connection with an apparatus for determining a small amount of heat generated due to, for instance, thermal reaction of erythrocytes derived from the same origin as that of plasma with plasma which contains cells and is obtained by lightly centrifuging blood, heparin-added blood to removing only erythrocytes therefrom. BACKGROUND OF THE INVENTION As the inventor has already reported on Diagnosis and Treatment according to Chinese Medicine (KANPO SHINRYO), October, Showa 60 (1985), p. 57, the inventor has tried to detect difference in reactivity of living bodies for the purpose of selecting herb medicines. As a result, it has been found that there is a specific relationship between thermal reactions of plasma containing cells, from which only erythrocytes are removed by a light centrifugation of human blood or heparin-added blood with erythrocytes derived from the same origin as that of plasma, sheep blood cells (heterologous erythrocyte) or PHA and diseases. However, conventional precision calorimeters comprise a detection bath disposed in a temperature controlled bath and a thermocouple and a pipe for passing samples therethrough disposed in the detection bath, the temperature controlled bath being filled with air or water and the detection bath being filled with air. In other words, since the thermocouple is surrounded by air layer in order to prevent corrosion thereof, there are problems such that it is difficult to control the temperature around the thermocouple and that it is difficult to detect the amount of heat in an accuracy sufficient to conduct the aforementioned medical inspection. From DE-A-3 049 105 a reactor calorimeter in particular for use in the chemical industry is known comprising a heater, an agitator and a detection bath which are disposed in a temperature controlled bath. Gaps between those parts are filled with a liquid as the gap between a detection unit and the detection bath. This device makes it possible to exactly determine thermocinetic data also with reactions accompanying consistence or volume alternations in particular for polymerisation reactions. Another calorimeter is described in Journal of Physics E-Scientific Instruments, vol. 13, No. 12, 1980, pages 1292 to 1296, The Institute of Physics, Dorking, G.B.S. Randzio et al "A flow calorimeter with active heat exchangers". Thermocouples are mounted in series on oxidised aluminum cylinders. On the lateral surface of the calometric block a heater is wound. A heating jacket and a cooler are provided outside of this block, the temperature thereof being controlled directly by an electronic temperature controller. This device gives temperature stability of the calorimetric block better than 10⁻⁴ deg and good uniformity in the range to about 450°C. The present invention has been completed from the viewpoint of the foregoing problems and it is an object of the present invention to provide a precision calorimeter which makes it possible to stably use it for a long period of time without causing corrosion of the portion for detecting quantity of heat, to easily control the temperature within the temperature controlled bath and to detect the amount of heat in a high precision. DISCLOSURE OF THE INVENTION The structural characteristics of the precision calorimeter according to the present invention which accomplish the aforementioned object resides in that said temperature-controlled bath container is filled with water, said detection unit further comprises a pipe for passing the sample therethrough, a reference heater and metallic blocks, wherein the pipe is provided with a mixer and the pipe, the reference heater and the thermocouple are positioned between the metallic blocks, said detection bath container is filled with perfluorocarbon sorrounding the detection unit for attaining a precise temperature control and reducing corrosion or oxidation of the thermocouple. Preferably a gap is maintained between the detection unit and said detection bath container. BRIEF EXPLANATION OF THE DRAWINGS Fig. 1 is a block diagram for explaining an example of the present invention; Fig. 2 is an exploded view of the detection block; Fig. 3 is a perspective view of an aluminum cylinder; Fig. 4 is a perspective view of the detection unit. THE MOST PREFERRED EMBODIMENT FOR CARRYING OUT THE INVENTION The precision calorimeter of the present invention will hereunder be explained with reference to the accompanying drawings which show the preferred embodiment of the present invention. As seen from Fig. 1, the precision calorimeter is constructed by the combination of a temperature controlled bath container 2 and a cover 4 which also serves as a bed for placing other elements. In the temperature controlled bath container 2, there are arranged a spiral heater 8 which is connected to a heat source 6 disposed outside the bath container, an agitator 12 which rotates within the spiral heater 8 by means of a motor 10 placed on the cover 4 and a detection unit 14. A proper amount of water is introduced in the temperature controlled bath. The detection unit 14 comprises a detection block 22 which is constructed by putting, between a thermocouple 20, a reference heater 16 consisting of one or a plurality of heating elements and a pipe 18 for passing samples therethrough, which is disposed so as to surround the reference heater and putting these elements between aluminum pieces 21. The detection block 22 is introduced in an aluminum cylinder 24 so as not to form gap therebetween and the aluminum cylinder 24 is inserted into an aluminum cylinder 26 provided with a cover member 25 so that a gap is maintained between them. The pipe 18 for passing samples therethrough is provided with a mixer 30, which is spaced apart from the reference heater 16 and the thermocouple 20 and is disposed between the aluminum pieces 21, and is communicated with two supply pipes 32 through the mixer 30. The supply pipes 32 are communicated to liquid pumps 52, 54 of an apparatus 50 for automatically supplying samples which is placed outside the temperature controlled bath container 2. The apparatus 50 for supplying samples has the same construction as known ones commercially available and is comprised of a rotary base 56 for support, an apparatus 58 for withdrawing and air pump 60. The reference heater 16 is connected to power supply 66 therefor through conductive wires 62, 64. The extremity of the pipe 18 for passing the samples therethrough which is not connected to the mixer 30 is communicated to an apparatus 68 for draining the sample. The thermocouple 20 is connected to an amplifier 72 through a conductive wire 70. In the foregoing construction, water 80 is introduced into the temperature controlled bath container 2, while the aluminum cylinder 26 is filled with perfluorocarbon 82. In this connection, if the difference between the temperature of water and room temperature is large, the temperature of water situated around the supply pipes 32 becomes low due to the supply of the sample maintained at room temperature and, therefore, it is desirable to dispose a preheater 90 around the supply pipes 32 for the purpose of preventing such temperature difference from causing. Now, the function of the foregoing example will hereunder be described. First of all, the heat source 6 is started to generate heat from the spiral heater 8, while the agitator 12 is also started to uniformly raise the temperature of the water 80 up to a desired value, for instance, 36°C. Then, the power supply 66 for the reference heater is started to generate heat from the reference heater 16 and thus the thermocouple 20 is calibrated. Thereafter, the plasma and erythrocytes or the like subjected to a proper treatment are supplied by means of liquid pumps 52, 54 with operating the preheater 90 while taking the difference between the temperature of water 80 and room temperature into consideration. These plasma and erythrocytes or the like are mixed by means of the mixer 30 to form a sample for instrumentation and the sample is supplied through the pipe 18 while causing thermal reaction. On the other hand, the quantity of heat due to the thermal reaction of the sample is detected by the thermocouple 20 as an increase of temperature. The signals thus detected are amplified by the amplifier 72 and are recorded by a recorder 74. In the precision calorimeter according to the present invention, the temperature control of the detection unit is affected utilizing liquids ie., water and perfluorocarbon. Therefore, the invention makes it possible to attain effects such that the temperature control is easily and precisely carried out and that precise measurement of the amount of heat generated can be carried out. In other words, when a conventional precision calorimeter, for instance, LKB (trade name) manufactured in Sweden is used, the measurement of the amount of heat is restricted to 10 to 100 micro W, however, it is demonstrated that the amount of heat up to 0.1 to 1 micro W can stably be determined according to the apparatus of the present invention. Moreover, as perfluorocarbon surrounds the detection unit, penetration of water into the detection unit can surely be prevented since the specific gravity of the perfluorocarbon is higher than that of water. Furthermore, the corrosion or oxidation of the thermocouple can thus substantially be reduced.

Claims: A precision calorimeter comprising a temperature-controlled bath container (2) having a heater (8) and an agitator (12), a detection bath container (26) disposed in said temperature-controlled bath container, said detection bath container having a detection unit (16, 18, 20, 21, 30) which is placed in the detection bath, the detection unit comprises a thermocouple (20) for detecting a quantity of heat due to a thermal reaction of a sample characterized in that said temperature-controlled bath container (2) is filled with water, said detection unit (16, 18, 20, 21, 30) further comprises a pipe (18) for passing the sample therethrough, a reference heater (16) and metallic blocks (21), wherein the pipe is provided with a mixer (30) and the pipe (18), the reference heater (16) and the thermocouple (20) are positioned between the metallic blocks, said detection bath container (26) is filled with perfluorocarbon surrounding the detection unit for attaining a precise temperature control and reducing corrosion or oxidation of the thermocouple (20). A precision calorimeter according to claim 1, characterized in that a gap is maintained between the detection unit (16) and said detection bath container (26).

Inventors: ITO, AKIHIRO, ITO, HIROYASU, ITO, SHOJIRO
Applicants: ITO, SHOJIRO
Application year: 1986
Main classification: G01N25
IPC codes: G01N33, G01N25, G01K17