Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
  • G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
  • G01N33/483—Physical analysis of biological material
  • G01N33/487—Physical analysis of biological material of liquid biological material
  • G01N33/49—Blood
  • G01N33/4905—Determining clotting time of blood
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F33/00—Other mixers; Mixing plants; Combinations of mixers
  • B01F33/45—Magnetic mixers; Mixers with magnetically driven stirrers
  • B01F33/452—Magnetic mixers; Mixers with magnetically driven stirrers using independent floating stirring elements
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
  • B01F35/40—Mounting or supporting mixing devices or receptacles; Clamping or holding arrangements therefor
  • B01F35/42—Clamping or holding arrangements for mounting receptacles on mixing devices
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
  • G01N21/01—Arrangements or apparatus for facilitating the optical investigation
  • G01N21/03—Cuvette constructions
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
  • G01N21/75—Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated
  • G01N21/77—Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated by observing the effect on a chemical indicator
  • G01N21/82—Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated by observing the effect on a chemical indicator producing a precipitate or turbidity
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F2101/00—Mixing characterised by the nature of the mixed materials or by the application field
  • B01F2101/23—Mixing of laboratory samples e.g. in preparation of analysing or testing properties of materials

Definitions

• the invention relates to a blood coagulation time measuring device and a method for recording and measuring the blood coagulation time with a temperature-controllable metal block serving to hold the measuring cuvette, a stirring device and a light-optical turbidity measuring device.
• the blood coagulation time is determined by measuring the turbidity of the sample that begins with blood coagulation, whereby mostly optical systems with a con constant lamp voltage and a photo amplifier with switch-off logic. These devices enable an automatic start, prevent contamination and have no moving parts. It is disadvantageous, however, that because of the slight change in turbidity that occurs during coagulation, high amplification must be achieved. This high gain inevitably leads to various interferences, for example to a high sensitivity to extraneous light. Measurements with caolin-stabilized reagents are not possible because the caolin settles during the measurement and this sedimentation leads to the device being switched off.
• Measurements with an oxalate plasma are also not possible because this leads to intermediate clouding, which also causes an early shutdown.
• these devices are very sensitive to vibrations.
• changeover switches are required with which the amplification can be adjusted. If the reagents or plasma are too cloudy, these devices can often no longer be used, since the optimal working point of the light sensor can no longer be achieved due to the darkened light path.
• the sensitivity of the devices in the pathological area generally only reaches up to about 25% Quick.
• a lamp voltage regulation basically has. the advantage that the working point of the photo sensor remains relatively constant over a large turbidity range. For this reason, no sensitivity switch is generally required.
• the object of the invention is to provide a generic blood coagulation time measuring device which, with simple handling of the measurement, allows the blood coagulation time to be determined reliably without the risk of incorrect measurements due to uncontrolled eddies in the sample or external light entering through the cuvette opening.
• Another object of the invention is to design the blood coagulation time measuring device in such a way that the measurement curves of the coagulation can be visualized.
• the object is achieved by combining the following features
• the stirring device is designed in a manner known per se as a magnetic stirring device which is located below the measuring channel serving to receive measuring cuvettes in the measuring block.
• Each measuring cell is held in the measuring channel by means of a clamping device.
• Each measuring cell is located in the light-optical beam path of a light-optical scanning device known per se, the light source of which is supplied with an operating voltage which is at least half the nominal voltage is and the light receiver is connected to a measurement unit with two threshold limiters.
• Fig. 1 shows an embodiment of the device according to the invention in a perspective view
• Fig. 2 shows the device of Fig. 1 in section A-A
• Fig. 3 shows the holder of the measuring cell as a detail in an enlarged view
• Fig. 4 shows the block diagram of another device according to the invention
• Fig. 5 shows a further embodiment of the device according to the Invention in a perspective view
• Fig. 6 is a partial view of the device of FIG. 5 in section B-B
• FIG. 7 shows a schematic block diagram of the device according to FIG. 5
• Fig. 9 shows a possible measured value display of the device according to Fig. 1 in a hematometric bar stall.
• the device 1, shown in perspective in FIG. 1, for recording and measuring the blood coagulation time has an operating part 3 and measuring part 4 combined in a housing 2.
• a control panel 9 is formed on the control part 3, which can have push buttons or rocker buttons, for example.
• a display field 10 is provided in the view plane of the operating part 3, which is preferably designed as an alphanumeric display.
• Various recesses are formed in the measuring surface 5 of the measuring part 4, which extend into the temperature-controllable measuring block
• a connection part 33 is also formed, through which a mains connection is possible.
• the device 1 can also be operated with a battery, not shown.
• a heater 12 is arranged in the metal block 11, which is preferably designed as an electrical heater. Through this heater
• the measuring block 11 is tempered uniformly, so that the cuvettes located in the preheaters 6, 7 and the measuring channel 8 are tempered uniformly.
• a light receiver 14 and a light source 15 of a Lichiopzian scanning device 13 are provided on both sides of the measuring channel 8.
• a metal tube 23 On the bath of the measuring cuvette 17 there is a metal tube 23, which can be put into place by the active intervention of the actuator. By rotating the Metallkogel 23 the sample in the measuring cell 17 is then mixed.
• a special clamping device 18 is provided for holding the measuring cuvette 17 in the measuring channel 8.
• This consists of a clamping member 19, which can be spherical, for example.
• the clamping member 19 is connected to a compression spring 20, which in turn is connected to an adjusting screw 21.
• the set screw 21 with the compression spring 20 and the clamping member 19 is screwed into a horizontal threaded bore 22 formed in the measuring block 11, the clamping member 19 resting against the wall of the measuring cuvette 17 under the tension of the compression spring 20. This is thereby held firmly in the measuring channel 8 without the insertion and removal of the measuring cell 17 from the measuring channel 8 being impaired.
• the clamping device 18 is arranged such that the light-optical beam path 32 of the light-optical device 13 is not impaired.
• the measuring unit 27 controls the lamp voltage and can be adjusted via the control panel 9 to adapt the device 1 to the color to be measured.
• the measured value unit 27 is connected to the display field 19.
• the measured value unit 27 can also be connected to a computer and processing unit 29.
• This computer and processing unit 29 consists of a computer 30 which is connected on the output side to the display unit 10 and, if appropriate, additionally to a printer 31.
• the computer 30 makes it possible, based on the data determined by the measurement, to calculate the respective blood characteristic values, to save them and, if necessary, to mix and compare them with other diacnosis data. It is also possible to supplement the device 1 so that a measurement of the aggregation is possible, so that a conclusion can be drawn from the measured values of the sample in the measuring cell 17 that a risk of thrombosis can be determined.
• the light receiver must be connected to an adjustable min / max amplifier 36, to whose output a line recorder 37 is connected. As shown in FIG. 4, it is possible to connect a connecting socket 34 to the connecting line 28 between the light receiver 14 and the amplifier 25, which can be located on the outer wall of the housing 2.
• the plug 35 of a connecting cable 35 a which is connected to the min / max amplifier 36, can be plugged into the connecting socket 34.
• a special actuator 38 is provided for setting the min / max amplifier 36.
• the special magnetic mixing system implemented in the device 1 and the regulated light path make it possible to determine the blood clotting time extremely reliably and precisely.
• the disadvantages present in other magnetic mixing systems are avoided by using a metal ball 23.
• This metal ball 23 stresses the sample to be measured so little that there are no time shifts in the turbidity process. Since the metal ball 23 cannot form a cavity in the measuring cuvette 17, fine air bubbles can also occur and lead to measuring errors.
• the metal ball 23 is very easy to separate, which considerably simplifies the handling of the device 1 by the ragged one Light path in which the lamp voltage cannot drop below 50% of the nominal voltage, the light source 15 emits so much light that the percentage of extraneous light is too low in percentage to be able to lead to faults.
• the characteristic curve of the lamp voltage change is such that the gain is greater in the lower voltage range, that is to say at about 50% of the nominal voltage, than in the upper range. The consequence of this is that clear samples are detected essentially more reliably. Since the linear range of the lamp voltage change for light brightness as well as the linear range of the light receiver 14 can be fully used, the range to be measured between clear and cloudy samples is significantly larger than known quantities.
• a special measuring cuvette 17 with, for example, a band thickness reduced by 25%, extreme measurements with diluted whole blood can also be carried out with the device 1.
• the measuring cuvette 17 is preferably designed such that the light-optical beam path 32 is not touched when 100 ⁇ l is added, but is exceeded when 200 ⁇ l is added.
• the device 1 can be used for all plasmas and reagents for all coagulation determinations.
• FIG. 5 shows a device 1 a, which is designed as a multi-channel coagulation time measuring device with a measured value display on a monitor 46. It also consists of an operating part 3a and a measuring part 4a. On the measurement part 4a, the monitor 46 is designed.
• Each six measuring cuvettes 17 can be stored in measuring channels 8a of a cuvette block 39.
• One cell block 39 each can be inserted into a recess 40 of the temperature-controllable measuring block 11a in such a way that the measuring cells 17 stored in the measuring channels 8a of the cell block 39 are in operative engagement with the magnetic stirring device 16a and the light-optical scanning device 13.
• recesses 48 which serve as preheaters and which are designed for the preparatory holding of two cuvette blocks 39.
• three recesses serving as preheater 7 are provided, which are used to hold receptacles for the reagent.
• a button selection device 47 which serves to operate the device 1 a.
• a cuvette block 39 consists of a metal rail in which the measuring channels 8a are arranged.
• the cuvette block 39 can be preheated to a temperature of 37 °, which is advantageous for the incubation.
• the magnetic stirring device 16a which consists of a plurality of stirring elements which can be controlled independently of one another, is arranged below the measuring cuvette 39 in the recess 40.
• Each scrambled element is assigned to a measuring channel 8 and thus to a measuring cell 17. This also applies to the scanning elements of the light-optical scanning device 13 a.
• Each measuring cuvette 17 is assigned a light source 15 and a light receiver 14, each of which can be controlled separately from the other light sources 15 and light receivers 14.
• the cuvette block 39 is uniformly heated by means of two heating elements 12a.
• the output line 41 connected to the light receivers 14 of the light-optical scanning device 13a is connected to an analog / digital converter 42 which is connected to a microprocessor 43 (FIG. 7a).
• the microprocessor 43 is connected via a control element 44 to the control element 44 designed as a key selection device 47 and to a monitor 46 as a data output device. It is also possible to connect a printer 31 to the microprocessor 43.
• the micro processor 43 is programmable by means of the key selector 47. According to its program, the microprocessor 43 selectively controls the light-optical scanning elements of the light-optical scanning device 13a assigned to a measuring cell 17 in the cell block 39.
• the microprocessor 43 also serves to control the threshold limiters.
• FIG. 7b Another embodiment of the device 1a is shown in a block diagram in FIG. 7b.
• Each light receiver 141 to 146 of the light scanner 13a is connected to an analog / digital converter 421 to 426 via an amplifier 251 to 256 and a transmission adjuster 261 to 266.
• Each analog-digital converter 421 to 426 is operatively connected to the microprocessor 43. For this purpose, there is one between each analog / digital converter 421 to 426 and the microprocessor 43
• Each amplifier 251 to 256 is also connected to the microprocessor 43 by means of a data line 66 and is operatively connected to the associated light source 151 to 155 by means of a control line 67. Control pulses of the microprocessor 43 for
• the setting of the respective voltage circuit of the light scanning device 13a is thus supplied to the light source 151 to 156 via the corresponding amplifier 251 to 256.
• a switching element 64 is assigned to each of these, to which a control line 67 is connected in each case.
• the light sensing circuit assigned to each measuring channel 8a can thus be individually controlled and regulated.
• the number of measuring channels 8a depends on the resolution of the monitor 46. six measuring channels 8a can be selected.
• the use of a device 1a with a monitor 46 with an analog data acquisition and a computer-controlled process sequence makes it possible to control the switching thresholds 49, 49a, 50, 50a by the microprocessor 43 and to adapt them to the unrest of the respective measurement.
• the switching thresholds 49, 50 are so far apart that in any case a start is achieved by pipetting reagent into the measuring cell 17.
• the large switching thresholds 49, 50 are intended to prevent faults such as automatic starts.
• the measurement signal 50 is automatically adjusted to the zero value 52.
• the maximum pulses 58, 59 of the measurement signal 50 are stored over a certain period of time.
• the upper and lower adjusted switching thresholds 49a, 50a are then pulled down positively as well as negatively via a certain value of the maximum pulse 58, 59.
• the device 1a is automatically optimized with respect to all reagents and determinations by means of the microprocessor 43 (FIG. 8).
• FIG. 9 shows an example of a display on a monitor 46.
• the dashed curves show the phases start 61, zero adjustment 62, switching threshold adjustment 63 and coagulation 54.
• the monitor 46 scr ⁇ t informs about the course of all six coagulation processes in the measuring cuvettes 17 simultaneously in the form of measurement curves 55.
• the start of the coagulation formation is a coagulation switch-off point in the form of a vertical Strokes 56 shown, each going through a measurement curve 55.
• the progress of the coagulation is indicated by a follow-up control 57, for example three seconds after the stop signal at the start of the coagulation formation.
• monitor 46 informs about the coagulation times in seconds, the percentage values calculated from the coagulation time, the mean value in the case of duplicate determination, the determination currently running, the entered patient identification number, the consecutive sample number, the temperature of the measuring block 11a, the incubation time and the set value Resolution of the measurement curves 55.
• the patient code can be entered via the key selection device 47, the switch-off point 53 of the automatic coagulation detection shifted, the resolution of the measurement curves 55 selected, and the printout via a printer
• the scanning elements of the light-optical Abuas device 13a assigned to each individual measuring channel 8a and stirring elements of the magnetic stirring device 16a can be started and stopped.
• all measuring channels 8a can also be reset simultaneously.
• the device 1a thus enables a plurality of measurements of blood coagulation times to be carried out and is therefore particularly suitable where a large number of such measurements have to be carried out in a short time.

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• Health & Medical Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Biomedical Technology (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Hematology (AREA)
• Analytical Chemistry (AREA)
• General Health & Medical Sciences (AREA)
• General Physics & Mathematics (AREA)
• Immunology (AREA)
• Pathology (AREA)
• Biochemistry (AREA)
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• Ecology (AREA)
• Molecular Biology (AREA)
• Urology & Nephrology (AREA)
• Food Science & Technology (AREA)
• Medicinal Chemistry (AREA)
• Plasma & Fusion (AREA)
• Investigating Or Analysing Biological Materials (AREA)
• Investigating Or Analysing Materials By Optical Means (AREA)

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• 1982
  • 1982-07-02 WO PCT/DE1982/000137 patent/WO1983000228A1/en unknown
  • 1982-07-02 JP JP57502175A patent/JPS58501096A/ja active Granted
  • 1982-07-02 EP EP82902153A patent/EP0083617A1/de not_active Withdrawn
• 1986
  • 1986-10-27 US US06/924,155 patent/US4876069A/en not_active Expired - Lifetime

Non-Patent Citations (1)

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