WO2010091739A1

WO2010091739A1 - Method and system for automatic analysis of release samples

Info

Publication number: WO2010091739A1
Application number: PCT/EP2009/051811
Authority: WO
Inventors: Hans-Jürgen KNITTER; Werner G. Müller
Original assignee: Erweka Gmbh
Priority date: 2009-02-16
Filing date: 2009-02-16
Publication date: 2010-08-19

Abstract

The invention relates to a method and to a system for automatically analyzing release samples, wherein a partial quantity of a release sample is removed from the test container, a first aliquot of the indicated partial quantity is UV-spectroscopically analyzed in a cuvette, and a second aliquot of the indicated partial quantity is simultaneously fed to a further analysis.

Description

Method and system for the automatic analysis of release samples

The present invention relates to a method and a system for the automatic analysis of release samples obtained in temperature-controllable test containers of a release test device during dissolution testing.

With the help of release test equipment, the release of a substance from a drug preparation in a solution is measured. Substances to be dissolved out of medicines in question, which are present, for example, in tablet form, as a capsule, granule or dragee, are particularly suitable substances to be dissolved out. Analytical methods for evaluating the release (dissolution, dissolution) of drug formulations have been introduced by the regulatory authorities of the pharmaceutical industry to describe release profiles of some specific formulations. Meanwhile, for reasons of quality control and for regulatory purposes, such methods are used in most formulations. Furthermore, release tests are used in the development of new formulations to determine the rate of release of the active compound from the formulation and other parameters related to efficacy, to establish optimal dosage forms, and to produce in vitro / in vivo correlations.

As a rule, several tablets are tested simultaneously, so that release test devices have several test vessels, in each of which one tablet is dissolved. In order to simulate as realistically as possible the dissolution of a tablet, as is done, for example, in the stomach, the test vessels are filled with a liquid similar to gastric juice and heated to body temperature. The heating can be carried out by placing the test vessels in a water bath at the desired temperature. The aim of the mentioned analytical methods is to analyze the time course of the release of active substances from a drug preparation. For this purpose, the specimens to be examined are dissolved in test vessels and checked at intervals, the concentration of the gone into active ingredients. It is necessary to take samples from the test vessels at the appropriate time intervals and to supply them to at least one analyzer. The necessary sampling took place in the past often manually. However, this can also be done automatically, wherein a certain volume of the solution contained in or in the test vessels is transferred to a vessel serving for intermediate storage. Parts of the respective samples are then transferred, usually manually, from the vessel mentioned to the HPLC vials of an autosampler of an HPLC system used for analysis.

As a further development, DE 10 2004 062 166 A1 describes a system for taking samples of a liquid medium and transferring sampled samples to a sample collecting unit with a sampler for taking samples from a container, pumps, connecting lines, valves accommodating the liquid medium Each container is associated with a sample holder in the form of a sample loop and with one pump each by means of which the liquid medium is kept in a continuous circulation leading from the test container through the associated sample loop and back into the container. In order to remove a sample from a test container, the circulation is interrupted by switching off the associated pump, and the medium in the sample loop is passed through the pump to the sample collection unit by means of a multiport valve. Such a system is very prone to failure due to the complex multi-port valve and requires a complex flushing of both the multiport valve and all piping systems up to the sample collection unit. A simultaneous measurement of several test vessels is not possible with such a device and between the individual sampling takes a relatively long time, since consuming must be rinsed. DE 8 210 451 U1 describes a device for taking and measuring analytical samples from a plurality of parallel-connected sample vessels for analysis in a single measuring device. In the process, solvent medium containing the substance to be analyzed is sucked out of the individual test vessels during the entire test period in sample circulations and returned again. If a sample is to be taken from one of the sample circuits and measured, the medium is forwarded by switching a valve via a central distributor to a measuring device connected thereto. Again, this device does not allow the simultaneous measurement of multiple samples and requires due to the long lines to a central valve, the removal of high volumes from the test vessels, so that a refilling of the test vessels during a series of measurements is required.

DE 10 2005 010 544 A1 describes a device for transferring dissolution samples from dissolution containers into bottles. Each dissolution sample is pumped from one of the dissolution containers through a suitable tube system to a corresponding bottle, independently of the other samples. Once sufficient dissolution sample is present in the bottles, a pump is stopped to allow one arm of an analyzer to grab the bottles and carry out the analysis of the dissolution samples within them. Above all, such a device has the disadvantage that a relatively large volume of liquid must be taken from the test vessel at each measurement time, so that in each case a corresponding volume of dissolution medium has to be filled into the test vessel. In addition, the movement of filled with samples bottles (vials) is complex and prone to failure.

DE 20 2007 017 023 U1 describes a device and a method for the automatic release and measurement of active substances from a drug preparation, wherein a sample is taken for the purpose of analysis with the aid of a program-controlled handling device with at least one gripper. Also in this system is in addition to an arrangement for the Sampling provided an additional arrangement for the return of medium in the test vessel for evaporation compensation.

It was therefore the object to provide a method and system that allows automatic analysis of release samples from test containers of a release test device, with as little sample as possible to be taken from the test containers and in addition to a UV spectroscopic analysis at least one other analysis method of same release sample of a measurement time can be performed.

The stated object was achieved by a method for the automatic analysis of release samples obtained in temperature-controllable test containers of a release test device in which a partial quantity of a release sample is taken from the test container, outside the test container a first aliquot of said partial quantity in a cuvette UV -spectroscopically examined and at the same time a second aliquot of said subset is fed to a further analysis. This method now has the decisive advantage that by dividing the subset taken from the test vessel into two aliquots, a simultaneous and multiple analysis of one and the same subset of the release sample can be carried out.

The terms release test device, dissolution test device and dissolution test device are used interchangeably for the purposes of the present invention, as are the terms release sample, dissolution sample and dissolution sample.

For the purposes of the present invention, a release sample may be a preparation of a drug dissolved or partially dissolved in a suitable dissolution medium. In particular, solid and semi-solid pharmaceutical forms, such as, for example, powders, powders, granules, tablets, dragées, capsules, effervescent tablets, pills or suppositoids, can be dissolved in the dissolution medium and thus tested as release samples. According to an advantageous embodiment of the method according to the invention, the extracted via a line from the test container to be analyzed subset of the release sample is then divided into two partial streams, wherein a first partial flow as said first aliquot UV spectroscopy measured and the second partial flow as said second aliquot with Help at least one other analysis method is examined. This method has the advantage that only a single line or the means located at the end of this line for taking a subset of the release sample must be immersed in the liquid of the test container. Thus, unnecessary turbulences that affect the dissolution process, avoided by the immersion of other sampling devices. The partial amount of the release sample taken, preferably with the aid of a syringe or a pump, is first drawn up into a storage tube or a comparable storage medium and then, if necessary after filtration of the liquid, passed via a line system into a cuvette for UV measurement. For the purposes of the present invention, a UV measurement or analysis of the first aliquot is understood to mean a UV spectroscopic or a UVA / IS spectroscopic analysis, wherein a combination with an NIR spectroscopy is also possible in each case.

A second aliquot of the same release sample is placed on an HPLC column or other suitable separation or analysis unit after switching a valve located just in front of the cuvette via a rheodyne valve. This procedure makes it possible to carry out a simultaneous UV spectroscopic measurement of the first aliquot in the cuvette and, after separation of the second aliquot of the subset of the release sample on a suitable HPLC column, its analysis with a suitable detector connected downstream of the HPLC column. Again, the samples are measured sequentially.

The remaining volume of release sample still present in the line system can be returned to the test vessel with the aid of the syringe or pump become. In an analogous manner, appropriate analyzes can be carried out with a suitable standard solution.

According to a further advantageous embodiment of the method according to the invention, the subset of the release sample is continuously conveyed out of the test container by means of a pump, passed through a flow cell and through a transfer vial and returned to the test container, wherein the flow cuvette is preferably arranged in front of the transfer vial , This results in particular the advantage that only a minimal subset of the release sample must be removed from the test container. The withdrawn subset is recycled by the circulation for the most part back into the test container. Only the second aliquot removed from the transfer vial is removed from the circulation. These advantages over the known methods result in particular from the fact that a subset of the liquid from the test vessel is pumped through a circulatory system and in this circuit both a cuvette for UV spectroscopic analysis and a transfer vial for taking a sample for further analysis be flowed through. In addition, no additional branched lines and valves are necessary.

Preferably, the pump is stopped at the time of measurement of the release sample, wherein in the flow cell, a UV spectroscopic measurement of said first aliquot and at the same time from the transfer vial, the removal of the second aliquot takes place. Thus, both the failure-prone switching valves and the rinsing of branched off from this circuit lines can be completely eliminated, since the measurement of the release sample can be done directly from the transfer vial directly in the flowed UV cuvette and on the other hand, the sampling.

According to a further advantageous embodiment variant, the subset of the release sample is introduced via an inflow into the transfer vial and discharged via a separate outlet and the sampling takes place via a closable third opening of the transfer vial. By the equipment of the Transfer vials with one inflow, one drain, and one opening for sampling may leave the transfer vial in a fixed location and need not be replaced with a new vial after sampling. This results directly from the fact that, after measurement or Probenent- take the pump is switched on in the circuit again, so that the solution located in the circuit outside the test vessel is returned to the test vessel and replaced with solution from the test vessel. In particular, it should be ensured that between two consecutive measurement times, the liquid in the circulatory system between the sampling point of the release sample in the test container to the transfer vial is completely replaced at least once. Only in this way can it be ensured that the conditions actually present in the test vessel are determined at each measuring time. In order to be able to carry out this exchange quickly, the volume of the cuvette, the transfer vial and the connecting hoses should be as small as possible.

Furthermore, it is advantageous if samples are taken from the transfer vial, that is, the second aliquot, for an online or offline measurement, the sampling especially for analysis using an HPLC device, an IR spectrometer, a GC MS device, an NMR device and / or a diode array spectrometer. In this case, the taken from the transfer vial aliquot of the subset of the release sample can either be supplied directly to one of said analyzers or transferred to each other vial and collected, the analysis can then take place at a later date.

The sampling from the transfer vial and the transfer to the analyzer or to another vial for storage of the sample can be done manually, but preferably automatically by means of a handling device.

A release test device usually comprises more than one test vessel, usually eight test vessels, in which release attempts simultaneously can be performed. For the purposes of the present invention, each test vessel of such a release test device can be equipped with the above-mentioned circulation system, which can be used alone for the UV spectroscopic measurement, a transfer vial and a pump. Thus, for several test containers, preferably eight, both UV measurements and the sampling for additional analysis can be performed simultaneously at a particular measurement time. The sampling from the transfer vials can easily be performed with a time delay. This can be achieved simply by switching on the pump in the respective circulatory system only when the desired aliquot has been removed from the transfer vial.

The abovementioned methods can be carried out particularly preferably with the aid of the system for the automatic analysis of release samples described below, this system according to the invention being followed by a dissolution test device for dissolution testing in temperature-controllable test containers and a means for taking a subset of the release sample which can be submerged in a test container , a flow cell for UV spectroscopic analysis of a first aliquot of the subset, a transfer vial for the removal of a second aliquot of the subset and a pump are connected by means of hoses in such a way that taken from the test container subset of a release sample the flow cell and the transfer vial and back into the test container can be performed. This arrangement allows complete avoidance of troublesome valves as well as removal of the vial for subsequent further analysis. Furthermore, no fresh medium must be refilled into the test vessel after measurement or sampling, since only the volume of the second aliquot is removed.

The flow cell is preferably arranged in front of the transfer vial. According to a preferred further development of the system, the pump for the circulation of the partial quantity is arranged between the transfer vial and the test vessel and the pump is preferably connected in such a way that the partial quantity is supplied to the pump. first the flow cell and then the transfer vial flows through. Alternatively, the pump in the circulatory system may also be connected between the test vessel and the cuvette for the UV measurement.

It is crucial that the volume of fluid formed by the connecting tube between the flow cell and the transfer vial be kept as low as possible. Preferably, this volume should be at most 1, 0 ml, preferably at most 0.5 ml. It follows that on the one hand, the distance between the cuvette and the transfer vial and the cross section of the connecting tube between these two devices must be as low as possible. This is of great importance since the measured value determined by the UV spectroscopic measurement and the measured value determined with the aid of the further analysis method are to be assigned to one and the same release sample for the sample taken from the transfer vial at one time of measurement. Since the released active ingredient concentration increases during the experimental procedure in the test vessel, it can nevertheless be ensured by the closest possible spatial arrangement of the UV cuvette and the transfer vial that the values of the at least two different analysis methods can be assigned to a single release sample at a specific time of measurement ,

The transfer vial preferably has an inflow, an outflow and a closable opening for removal of the second aliquot. In this case, the closable opening for removing the second aliquot of the transfer vial is closed with a septum. This embodiment of the transfer vial allows, on the one hand, the passage of the release sample through the vessel and, on the other hand, the easy removal of the second aliquot for further analysis, for example by piercing a cannula through the septum.

In an advantageous further development of the system according to the invention is in spatial proximity to the transfer vial or - in the case of multiple test vessels - to the transfer vials a rack for collecting the samples taken for the further analysis is arranged, wherein the further analysis device is preferably an HPLC device, an IR spectrometer, an NMR device, a GC-MS device, a diode array spectrometer or a similar suitable separation or analysis device. Such an arrangement has the advantage that the samples taken from the transfer vial can first be collected, later analyzed and then assigned to the respectively determined UV values. Thus, the parameters to be determined during a release test can be recorded at the desired times for the release sample. Furthermore, it is advantageous if a programmable handling device is provided for the removal of the aliquot from the transfer vial and / or the transfer to the further analysis device or to its sample collector.

The means for the removal of the subset from the test vessel is preferably a frit, a filter, a tube or a cannula, which is connected via a hose to the cuvette.

The individual test vessels can still be equipped with video cameras, so that the dissolution process can also be visually tracked. The recording is preferably carried out in fast motion. Optionally, then for a release sample at a measurement time, an assignment of a video recording to the analysis values of the UV determination and the further analysis can take place.

Further details and advantages of the method and system according to the invention are described below with reference to the drawings for some embodiments. Show it:

Fig. 1 The simultaneous analysis of a release sample by means of a UV measurement and an HPLC system with optional filtration of the sample and 2 a connected to a test vessel circulatory system consisting of a cuvette, a transfer vial and a pump, which are connected to each other via suitable hoses.

According to the embodiment of Fig. 1, for the purpose of analysis of a release sample, first a tube connected to the conduit 10 is immersed in the release sample 5 of a test vessel 1 and with the aid of the syringe 15 via lines 10, 12 and 13 a suitable subset of the release sample removed from the test vessel 1 and stored in the storage hose 13. After appropriate switching of the valves V2, V3, V4 and V5, a first aliquot of the release sample stored in the storage tube 13 by means of the syringe 15 via the lines 13, 16 and 19 in the cuvette 20, preferably a quartz cuvette, are initiated. After switching over the valve V5, a second aliquot of the release sample stored in the storage tube 13 can be forced into the line 21 via the line 22 via the line 22 via a rheodynamic valve. At the same time, the release sample (first aliquot) in the cuvette 20 can be measured simultaneously by UV spectroscopy and a second part of the sample (second aliquot) can be separated on the HPLC column 25, the pressure being transferred from an HPLC pump, not shown in the drawing the line 24 is constructed and the analysis is performed by means of a suitable HPLC detector 26.

Subsequently, after switching the valve V6, fresh dissolution medium can be drawn up into the syringe 15 via the line 14 so that the syringe 15 can push back the portions of release sample remaining in the lines 13, 12 and 10 into the test vessel 1. In an analogous manner, the lines 16, 19, 22 and 21 and the Rheodyne valve can be flushed with fresh dissolution medium accordingly after switching the valves V2 and V5. If additional filtration of the release sample before the measurement is not desired, the sample can be carried out by means of appropriate switching of the valves V3 and V4 instead of through line 16 also through the line 17 without filter station 18. In the case of the use of a reference solution, according to FIG. 1, first a tube connected to the line 11 is immersed in the vessel 27 with a reference solution and then a suitable amount of reference solution is drawn into the storage tube 13 with the aid of the syringe 15. The further analysis is carried out analogously to the above-described measurement of a release sample in the cuvette 20 and on the HPLC system, in which case the standard solution is transported from the reserve tube 13 via the line 17 without filtration. Residual standard solution can also be pushed back from the lines 13, 12 and 1 1 in the vessel 27, with a last remainder to avoid the dilution of the standard solution from the line 11 must be pressed into a waste vessel 28.

Fig. 2 shows a further embodiment of the system according to the invention. In this variant, a cuvette 2 for UV spectroscopic measurement, a transfer vial 3 and a pump 4 are arranged in series one behind the other and connected to each other with suitable hoses. Thus, the portion of the release sample 5 pumped out of the test vessel 1 can be passed through the cuvette 2 and the transfer vial 3 with the aid of a tube 7 immersed in the liquid and returned to the test vessel 1. A part of the release sample 5 of the test vessel 1 thus circulates continuously through the cuvette 2 and the transfer vial 3, the flow direction being indicated by an arrow. It is important to ensure that in particular the tubing of the devices is arranged so that the smallest possible volume of release sample 5 is removed from the circulation system from the test vessel 1.

When a measuring time is reached, the pump 4 is switched off so that the liquid rests in the circulatory system. Then a measurement of the subset of the release sample 5 in the cuvette 2 (first aliquot) and a removal of a sample (second aliquot) from the transfer vial 3 can take place. The removal of the second aliquot from the transfer vial 3 can take place with the aid of a cannula, not shown in the drawing, which is pricked by a septum located on the transfer vial 3. After removal the sample, the pump 4 can be turned on again. The removed sample can then be immediately supplied to a corresponding separation of an HPLC column or alternatively temporarily stored in a vial. The analysis value determined later for this intermediate sample can then be assigned to the UV spectroscopic data set determined in the cuvette.

In the case of a plurality of test vessels, preferably eight, in a release test device, each test vessel 1 is assigned the circuit arrangement shown in FIG. 2. This means that eight UV cuvettes and eight transfer vials and eight pumps would be required. In this case, a plurality of transfer vials 3 could be accommodated in a rack 6.

LIST OF REFERENCE NUMBERS

1 test container, test vessel

2 flow cell, cuvette

3 transfer vials

4 pump

5 release sample

6 rack for transfer vials

7 frit, filter, tube or cannula

10, 11, 12 lines

13 storage hose

14 line

15 syringe

16, 17 lines

18 filters

19, 21, 22 lines

20 cuvette

23 Rheodyneventil

24 line

25 HPLC column

26 Detector for HPLC column

27 containers for standard solution

28 waste containers

Claims

claims:

A method for the automatic analysis of release samples, characterized in that

- a subset of a release sample is taken from the test container,

- A first aliquot of said subset is examined in a cuvette UV spectroscopy outside the test container and

- At the same time a second aliquot of said subset is fed to a further analysis.

2. The method according to claim 1, characterized in that the extracted via a line from the test container to be analyzed subset of the release sample is then divided into two partial streams, wherein a first partial flow as the said first aliquot measured by UV spectroscopy and the second partial flow as the said second aliquot is examined by means of at least one further analysis method.

3. The method according to claim 1, characterized in that the subset of the release sample continuously conveyed by means of a pump out of the test container, passed through a flow cell and by a transfer vial and returned to the test container, wherein the flow cell is preferably arranged in front of the transfer vial is.

4. The method according to claim 3, characterized in that at the time of measuring the release sample, the pump is stopped, in the flow cell, a UV spectroscopic measurement of said first aliquot and at the same time from the transfer vial, the removal of the second aliquot takes place.

5. The method according to claim 4, characterized in that the subset of the release sample is introduced via an inflow into the transfer vial and discharged via a separate outlet and the sampling takes place via a closable third opening of the transfer vial.

6. The method according to claim 5, characterized in that between two consecutive measurement times, the liquid in the circulatory system between the sampling point of the release sample in the test container to the transfer vial is completely replaced at least once.

7. The method according to claim 6, characterized in that taken from the transfer vial samples for online or offline measurement, in particular for an HPLC device, an I R spectrometer, a GC-MS device, an NMR device and / or a diode array spectrometer.

8. The system for automatically analyzing release samples according to claim 3, wherein the system is connected to a dissolution test device for dissolution testing in test containers, characterized in that a means, which can be submerged in a test container for taking a subset of the release sample, is a flow-through cuvette for the UV spectroscopic analysis of a first aliquot of the subset, a transfer vial for taking a second aliquot of the subset and a pump connected by means of hoses in such a way that taken from the test container subset of a release sample through the flow cell and the transfer vial and back into the test container can be performed.

9. System according to claim 8, characterized in that the flow cell is arranged in front of the transfer vial.

10. System according to claim 9, characterized in that the pump for the circulation of the subset between the transfer vial and the test vessel is arranged and the pump is preferably connected so that the TeN- flow through the flow cell first and then the transfer vial.

11. A system according to claim 10, characterized in that the transfervial has an inflow, an outflow and a closable opening for removal of the second aliquot.

12. System according to claim 11, characterized in that the closable opening for the removal of the second aliquot of the transfer vial is closed with a septum.

13. System according to claim 12, characterized in that the connecting tube between the flow cell and the transfer vial has a maximum volume of xxx ml, preferably of at most xxx ml.

14. The system according to claim 13, characterized in that a rack for collecting the removed second aliquots for further analysis is arranged in spatial proximity to the transfer vial, wherein the further analysis device is preferably an HPLC device, an IR spectrometer, an NMR Device, a GC-MS device and / or a diode array spectrometer are / is.

15. System according to claim 14, characterized in that for the removal of the second aliquot from the transfer vial and / or the transfer to the further analysis device or its rack for collecting the samples, a programmable handling device is provided.

16. System according to claim 15, characterized in that the means for the removal of the subset of the test vessel is a frit, a filter, a tube or a cannula.

Ask: Delimitation from claim 1 to DE 20 2007 017 023 U1 (E9P1) sufficient?

Also described there UV + HPLC, but no division into two AIi- quots

Fig. 1 (claim 2)

- also parallel for several test vessels? Then several UV cuvettes and HPLC columns necessary? Or time-delayed analysis

- Differentiation from DE 20 2007 017 023 U1 (E9P1) Fig. 11 (pp. 10, 21, 22 of the description)? Differences: here no second syringe for medium compensation necessary, here division of the sample into two streams

Removal of the subset from the test vessel (claim 16)

Can a discharge and an inflow be integrated directly into the test vessel to remove the partial quantity from the test vessel? Then no pipe o.a. permanently immersed in the liquid