Techniques for checking the validity of the mass axis calibration of a mass spectrometer in an analyzer system

Abstract

In one aspect, the present disclosure relates to a method for checking the validity of the mass axis calibration of a mass spectrometer (MS) of an analyzer system, the method comprising: obtaining a mass axis check sample spanning a predetermined m / z measurement range of the mass spectrometer; and automatically processing the mass axis check sample, comprising: using the MS to perform multiple full-scan mode MS measurements of different types on at least two mass axis points within the predetermined m / z measurement range of the MS to obtain measurement data, wherein the different types include at least a first full-scan MS measurement in a positive mode and a second measurement in a negative mode or at least a first full-scan measurement of a first mass filter of the mass spectrometer and a second full-scan mode of a second mass filter of the mass spectrometer; wherein the multiple different full-scan MS measurements are selected so that the maximum measurement time in the mass spectrometer is less than 5 minutes; comparing the measurement data of each of the at least two mass axis points with corresponding reference data; and determining whether the mass axis calibration condition is out of specification based on the result of the comparison step.

Description

Technical Field

[0001] The present disclosure relates to methods and apparatus for mass spectrometry. In particular, the present disclosure relates to methods and systems for checking the validity of the mass axis calibration of a mass spectrometer. Background Art

[0002] The implementation of mass spectrometry, and more specifically liquid chromatography-mass spectrometry, is gaining increasing attention in clinical and other laboratory environments. In these environments, it is often necessary to process a variety of different assays in a highly automated manner, and if possible, to use a random access mode (i.e., the analyzer can perform any one of multiple assays at any one time, as opposed to systems that require batches of a specific assay for a large number of samples or only process one or two assays over a longer period of time). Consequently, the mass spectrometer may have to provide a relatively wide m / z measurement range at any given time to be ready to process the corresponding assays.

[0003] This high degree of flexibility can require extensive monitoring, quality control, and calibration operations to ensure that the analyzer system is operating within specifications. In particular, the mass axis of the mass spectrometer requires regular calibration, as mass axis accuracy can be a critical factor in the operation of the analyzer system.

[0004] Therefore, different mass axis calibration procedures must be used to ensure correct mass axis calibration. Many known calibration techniques involve dedicated manual processes that require interference with the automated operation of the analyzer system. In addition, these calibration procedures may take a relatively long period of time (e.g., in some examples, tens of minutes or even more than an hour). Obviously, such procedures constitute a considerable interference with the operation of the analyzer system, which greatly reduces the productivity of the analyzer system. For these reasons, it is desirable to limit the frequency of such mass axis calibration procedures. In some prior art analyzer systems, a frequency of once every six months or once a year has been proposed. Summary of the Invention

[0005] In one general aspect, the present invention relates to a method for checking the validity of the mass axis calibration of a mass spectrometer (MS) of an analyzer system. The method includes: obtaining a mass axis check sample spanning a predetermined m / z measurement range of the mass spectrometer; and automatically processing the mass axis check sample. The automated processing of the mass axis check sample includes: using the MS to perform a plurality of full scan mode MS measurements of different types on at least two mass axis points within the predetermined m / z measurement range of the MS to obtain measurement data. The different types include at least a first full scan MS measurement in a positive mode and a second measurement in a negative mode or at least a first full scan measurement of a first mass filter of the mass spectrometer and a second full scan mode of a second mass filter of the mass spectrometer. The plurality of different full scan MS measurements are selected so that the maximum measurement time in the mass spectrometer is less than 5 minutes. The method further includes: comparing the measurement data of each of the at least two mass axis points with corresponding reference data; and determining whether the mass axis calibration condition is out of specification based on the result of the comparing step.

[0006] In a second general aspect, the invention relates to a computing system configured to perform the steps of the method of the first general aspect.

[0007] In a third general aspect, the invention relates to a computer-readable medium containing instructions stored thereon, which instructions, when executed by a processor of a computing system, prompt the computing system to perform the steps of the method of the first general aspect.

[0008] The techniques of the first to third general aspects may have advantageous technical effects.

[0009] First, the technique for checking the effectiveness of the mass axis calibration of a mass spectrometer of an analyzer system can provide a relatively quick check of the mass axis accuracy compared to some prior art techniques. In this way, the mass axis check procedure can be performed (relatively) frequently and without causing substantial interference with the operation of the analyzer. The technology of the present disclosure exploits the insight that even a relatively short measurement time may be sufficient to gain insight into the state of the mass axis calibration of a mass spectrometer (although the measurements performed within this short measurement time may not be sufficient for actual mass axis calibration). In other words, the technology of the present disclosure involves performing a potentially rough "status check" of the mass axis calibration. The check of the present disclosure may not produce enough information to perform a mass axis adjustment. Instead, it is designed to discover whether there is a problem that requires further attention (or whether there is no problem and the analyzer can resume its normal operation).

[0010] Second, the mass axis check technique of the present disclosure can be performed in an automated analyzer system with no (or minimal) additional hardware. For example, the analyzer flow that is also used to process patient samples (e.g., an LC flow connected to an MS) can be used to process the mass axis check samples of the mass axis check technique of the present disclosure.

[0011] Additionally or alternatively, the mass axis check sample may be readily available in the analyzer system (e.g., a quality control sample or internal standard), thereby eliminating the need for dedicated additional consumables in some examples. Furthermore, in some examples, the mass axis check sample may be prepared on-site by the analyzer system (possibly also providing the mass axis check sample in an additional cartridge or other container).

[0012] Thus, in some examples, the mass axis checking procedure can be performed in existing analyzer systems without modifying their hardware.

[0013] Third, the disclosed techniques can allow for preventative scheduling of calibration or maintenance operations by providing a tighter frequency for mass axis inspection operations. This may not be feasible using some existing techniques because performing these techniques disrupts the normal operation of the analyzer and because their duration is relatively long. In this way, more serious failures that could result in extended analyzer downtime can be prevented in some cases.

[0014] The term "measurement time in the mass spectrometer" relates to the period of time during which a particular sample is processed by the mass spectrometer of the analyzer system.

[0015] An "analyzer system" according to the present disclosure is an automated laboratory device dedicated to the analysis of samples (eg, samples for in vitro diagnosis). For example, the analyzer system may be a clinical diagnostic system for performing in vitro diagnosis.

[0016] Depending on the needs and / or the desired laboratory workflow, the analyzer system of the present disclosure may have different configurations. Additional configurations may be obtained by coupling multiple instruments and / or modules together. A "module" is a working unit having a dedicated function, typically smaller in size than the entire automated analyzer system. This function may be an analytical function, but may also be a pre-analytical function or a post-analytical function, or may be an auxiliary function of any of the pre-analytical function, the analytical function, or the post-analytical function. In particular, a module may be configured to collaborate with one or more other modules for performing a dedicated task of a sample processing workflow, for example, by performing one or more pre-analytical steps and / or analytical steps and / or post-analytical steps.

[0017] In particular, an analyzer may include one or more analytical devices designed to perform respective workflows optimized for certain types of analysis.

[0018] The analyzer system of the present disclosure includes a mass spectrometer, optionally in combination with a liquid chromatography device (LC). In addition, the automated analyzer system may include analytical equipment for one or more of clinical chemistry, immunochemistry, coagulation, hematology, etc.

[0019] Thus, the analyzer system may comprise an analytical device or a combination of any such analytical devices with corresponding workflows, wherein the pre-analytical module and / or the post-analytical module may be coupled to a separate analytical device or may be shared by a plurality of analytical devices. In an alternative embodiment, the pre-analytical function and / or the post-analytical function may be performed by a unit integrated in the analytical instrument. The automated analyzer system may comprise functional units, such as liquid handling units for pipetting and / or pumping and / or mixing samples and / or reagents and / or system fluids, and functional units for sorting, storing, transporting, identifying, separating, detecting.

[0020] The term "sample" refers to a biological material suspected of containing one or more analytes of interest and whose detection, identification and / or quantification may be associated with a particular condition (eg, a clinical condition).

[0021] The sample may be from any biological source, such as physiological fluids, including blood, saliva, lens fluid, cerebrospinal fluid, sweat, urine, milk, ascites, mucus, synovial fluid, peritoneal fluid, amniotic fluid, tissue, cells, etc. The sample may be pre-treated before use, such as preparing plasma from blood, diluting viscous liquids, lysing, etc.; the processing methods may involve filtration, centrifugation, distillation, concentration, inactivation of interfering components, and addition of reagents. In some cases, the sample may be used directly as obtained from the source or may be used following a pre-treatment and / or sample preparation workflow to modify the characteristics of the sample (e.g., after adding an internal standard, after dilution with another solution, or after mixing with a reagent), for example, to enable one or more in vitro diagnostic tests, or to enrich (extract / separate / concentrate) the analyte of interest and / or remove matrix components that may interfere with the detection of the analyte of interest.

[0022] The term "sample" is intended to refer to a sample before sample preparation, while the term "prepared sample" is used to refer to a sample after sample preparation. In the absence of a specific term, the term "sample" may generally refer to a sample before sample preparation, a sample after sample preparation, or both. In general, examples of target analytes are vitamin D, drugs of abuse, therapeutic drugs, hormones, and metabolites. However, this list is not exhaustive.

[0023] In particular, the analyzer system includes a sample preparation station for the automated preparation of samples. A "sample preparation station" is a pre-analytical module coupled to one or more analytical devices or units in an analytical device that is designed to perform a series of sample processing steps intended to remove or at least reduce interfering matrix components in the sample and / or enrich the target analyte in the sample. Such processing steps may include any one or more of the following processing operations performed sequentially, in parallel, or staggered on one or more samples: pipetting (sucking and / or dispensing) fluid, pumping fluid, mixing with reagents, incubating at a certain temperature, heating or cooling, centrifuging, separating, filtering, screening, drying, washing, resuspending, aliquoting, transferring, storing ...).

[0024] " reagent " is the material for treating sample so that for example, the sample for analysis is prepared, and effect is to make reaction or make it possible to detect the physical parameter of analyte contained in sample or sample. Especially, reagent can be as reactant or the material comprising reactant, normally can be for example combined with one or more analytes in sample or unwanted matrix component in sample or make it to chemical conversion compound or medicament. The example of reactant is enzyme, enzyme substrate, the dyestuff of putting together, protein binding molecule, part, nucleic acid binding molecule, antibody, chelating agent, enhancer, inhibitor, epitope, antigen etc. However, term reagent is used to include any fluid that can be added to sample, including diluent (including water or other solvent or buffer solution), or for destroying the material of specificity or non-specific binding of analyte and protein, conjugated protein or surface.

[0025] For example, the sample can be provided in a sample container, such as a sample tube (including primary and secondary tubes), a multi-well plate, or any other sample carrying support. Reagents can be arranged, for example, in the form of a container or box containing a separate reagent, a reagent set, and placed in a suitable receptacle or position in a storage compartment or a conveyor. Other types of reagents or system fluids can be provided in bulk containers or supplied via pipelines.

[0026] "LC stream" is a fluid line comprising at least one capillary tubing and / or LC column comprising a stationary phase selected according to the type of sample and analyte, and through which a mobile phase is pumped to capture and / or separate and elute and / or transfer the analyte of interest under selected conditions (e.g., according to their polarity or log P value, size, or affinity), as is known. At least one LC column in at least one LC stream can be interchangeable. In particular, an LC separation station can comprise more LC columns than LC streams, wherein multiple LC columns can be interchangeably coupled to the same LC stream. The capillary tubing can bypass the LC column, or the dead volume can be adjusted to fine-tune the elution time window.

[0027] Unless otherwise specified in the respective context, the term "about" in relation to a parameter value means including a deviation of + / - 10% relative to the specified value in the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a flow chart illustrating the quality axis inspection technique of the present disclosure.

[0029] Figure 2 、 Figure 3 and Figure 4 is a flow chart illustrating an exemplary quality axis inspection technique of the present disclosure.

[0030] Figure 5 、 Figure 6 、 Figure 7 as well as Figure 8a and Figure 8b Shown are exemplary measurement results obtained when using the techniques of this disclosure.

[0031] Figure 9 An exemplary analyzer system according to the present disclosure is shown. DETAILED DESCRIPTION

[0032] First, combine Figure 1 An overview of the disclosed technology is given. Further aspects of the disclosed quality axis inspection technology will be discussed later. Figure 2 Finally, the Figure 9 Aspects of the analyzer system of the present disclosure are discussed.

[0033] Figure 1 is a flow chart illustrating the quality axis inspection technique of the present disclosure.

[0034] A method for checking the validity of a mass axis calibration of a mass spectrometer of an analyzer system comprises obtaining 101 a mass axis check sample spanning a predetermined m / z measurement range of the mass spectrometer and automatically processing 105 the mass axis check sample. This automatic processing step comprises a set of sub-steps.

[0035] Specifically, the technique includes performing 107 a plurality of full scan mode MS measurements of different types on at least two mass axis points within a predetermined m / z measurement range of the MS to obtain measurement data. The different types may include at least a first full scan MS measurement in a positive mode and a second measurement in a negative mode and / or at least a first full scan measurement of a first mass filter of the mass spectrometer and a second full scan measurement of a second mass filter of the mass spectrometer.

[0036] A number of different full-scan MS measurements were selected such that the maximum measurement time in the mass spectrometer was less than 5 minutes. The "measurement time in the mass spectrometer" refers to the time after the mass axis check sample has been injected into the mass spectrometer when the actual mass spectrometer measurement is performed. The "measurement time in the mass spectrometer" does not include, for example, the processing time of the mass axis check sample in the liquid chromatograph or in other optional modules located upstream of the mass spectrometer. Furthermore, the "measurement time in the mass spectrometer" does not include any preparation steps for the mass axis check sample that may occur in some examples.

[0037] The method further comprises comparing 111 the measurement data of each of the at least two mass axis points with corresponding reference data; and determining 113 whether the mass axis calibration condition is out of specification based on a result of the comparing step.

[0038] In some examples, if the mass axis calibration condition is out of specification, a mass axis adjustment procedure including separate measurements is triggered 117. If the mass axis calibration condition is within specification (i.e., not out of specification), operation of the mass spectrometer can be resumed 115. Other responses that can be triggered are discussed below.

[0039] As described above, measurements of the mass axis inspection technique of the present disclosure can be performed relatively quickly (ie, with a measurement time of less than 5 minutes). In some examples, the measurement time in mass can be less than 2 minutes or less than 1 minute.

[0040] In many cases, an analyzer system including a mass spectrometer can operate based on a specific clock (i.e., a predetermined time period during which the mass spectrometer processes a particular sample in a single measurement process (also referred to herein as a "measurement window"). For example, as described below, the duration of this predetermined time period can be a duration of less than 5 minutes (e.g., a duration of less than 1 minute, or a duration of 36 seconds). In some examples, this predetermined time period is the time period during which one of a plurality of chromatographic streams is connected to the mass spectrometer. An automated scheduler for this type of analyzer system can schedule the processing time slots of the mass spectrometer to be in time slots having a duration of the predetermined time period.

[0041] The technology of the present disclosure may include scheduling the processing of quality axis check samples in an automated scheduling process for an analyzer system. Scheduling the processing of quality axis check samples in an automated scheduling process may include minimizing the impact on the throughput of a mass spectrometer or an analyzer including a mass spectrometer (e.g., by performing specific optimization techniques). For example, a scheduler may fill the idle time of an automated analyzer / mass spectrometer with the quality axis check routine described herein. For example, a scheduler may schedule the quality axis check routine when no patient samples are being processed or when the workload of the analyzer system is low.

[0042] In some examples, the maximum measurement time is selected to be the duration of a measurement window for a production sample of the mass spectrometer (or a shorter than comparable measurement window). In other examples, the maximum measurement time of the method for checking the validity of the mass axis calibration of the mass spectrometer is selected to be an integer multiple of the duration of this measurement window. This allows the mass axis check of the present disclosure to be inserted into the "normal" scheduling and processing operation of the analyzer system. Many prior art calibration techniques are too time-consuming and / or require modification of the analyzer system and therefore cannot be easily included in the "daily operation" of the analyzer system.

[0043] In some examples, the different measurements performed during the mass axis inspection technique can be selected so as not to exceed the maximum measurement time. Depending on the analyzer system, this may allow for a greater or lesser number of different measurements to be performed for at least two mass axis points covering the mass spectrometer's measurement range. In any case, the present technique includes performing different types of full scan mode MS measurements during this duration.

[0044] In other examples, the method for the validity of the mass axis calibration of the inspection mass spectrometer includes being less than 50 measurement cycles (for example, being less than 40 measurement cycles), and wherein mass interval is at least 2amu (for example, at least 3amu).In this context, " measurement cycle " of mass spectrometer refers to the single scan of the m / z than range scanned in the covering measurement." mass interval " refers to the distance (on mass axis) between two different measurement points scanned.When selecting smaller step length, for specific m / z, generate larger number of measurement points (and vice versa) than range.

[0045] Figure 1 The technique uses a mass axis that spans a predetermined m / z measurement range of a mass spectrometer to examine a sample. In some examples, the predetermined measurement range of a mass spectrometer is the maximum measurement range provided by the mass spectrometer. In other words, the predetermined measurement range can be the maximum measurement range for which a particular model or type of mass spectrometer is designed. The measurement range of a mass spectrometer can span from 10 amu to 5000 amu, and optionally from 15 amu to 3000 amu.

[0046] Additionally or alternatively, the predetermined m / z measurement range of the mass spectrometer can be defined by the plurality of analytes to be analyzed by the mass spectrometer. In these examples, the full m / z measurement range can span the m / z range from the analyte requiring the lowest m / z ratio to the analyte requiring the highest m / z ratio of the plurality of analytes to be measured by the mass spectrometer. In these examples, the full measurement range can vary (even for the same type of analyzer) depending on the assay to be processed by the analyzer.

[0047] For example, if the lowest m / z ratio for a group of analytes is between 120 amu and 140 amu for valproic acid, and the highest m / z ratio is between 1200 amu and 1210 amu for cyclosporin A, then the predetermined m / z measurement range may be in the range of between 100 amu and 1300 amu. This range may be different for a different group of analytes. In some examples, the predetermined m / z measurement range may also vary over time for a particular mass spectrometer, for example, if the group of analytes to be processed by the mass spectrometer changes.

[0048] In any case, the technology of this disclosure is directed to a measurement range with a specific minimum width. For example, the minimum width of the measurement range may be 1000 amu or 5000 amu.

[0049] In the technology of the present disclosure, a mass axis check sample is used to facilitate the mass axis check process. In some examples, the mass axis check sample includes a mixture of two or more different substances spanning the full m / z measurement range of the mass spectrometer, wherein the at least two mass axis points are provided by different substances in the mixture. The mass axis check sample may include one or more analytes, solvent molecules, additives, and salts. In some examples, an internal standard may be used as the mass axis check sample. Further aspects of the mixture are discussed below.

[0050] Exemplary Quality Axis Inspection Techniques

[0051] Figure 2 、 Figure 3 and Figure 4 is a flow chart illustrating an exemplary quality axis inspection technique of the present disclosure.

[0052] exist Figure 2 In the present invention, the mass axis inspection technique begins with a triggering event 201. The triggering event can be the execution of a specific routine or operation in an analyzer system or mass spectrometer. For example, the method can be performed in one or more of the following situations: 1) during a quality control routine of a mass spectrometer or an analyzer including a mass spectrometer, 2) during a routine instrument check of a mass spectrometer or an analyzer including a mass spectrometer, 3) during a startup procedure of a mass spectrometer or an analyzer including a mass spectrometer, 4) during downtime of a mass spectrometer or an analyzer including a mass spectrometer, or 5) during or after a repair or maintenance operation of a mass spectrometer or an analyzer including a mass spectrometer.

[0053] In all of these examples, the relatively short quality axis inspection routine can be conveniently integrated (in an automated manner) into the process flow. In particular, the routine can be scheduled by the automated analyzer's scheduler. In other cases, the routine may involve manual operation or be triggered by an operator's decision. However, the automated analyzer's scheduler can detect that the routine is to be executed and schedule the quality axis inspection technique of the present disclosure.

[0054] In other examples, the triggering event includes one or more of: 1) a change in state of a mass spectrometer or an analyzer system including a mass spectrometer, 2) a monitored parameter of the mass spectrometer or an analyzer system including a mass spectrometer taking on a specific value or exceeding a specific threshold, 3) a monitored parameter of the mass spectrometer environment, or 4) detection of an error in the mass spectrometer or an analyzer system including a mass spectrometer.

[0055] For example, Figure 2 As shown, a temperature deviation may be detected in an analyzer system (eg, a mass spectrometer) or in the analyzer environment (in other examples, changes in other parameters such as humidity may also be detected). This may trigger the mass axis check procedure of the present disclosure.

[0056] In the previous section, several triggering events have been discussed. However, the technology of the present disclosure can also be repeatedly performed during the production mode of the mass spectrometer. In some examples, the method can be performed at regular time intervals. For example, for a specific mass spectrometer, the method can be performed at least once an hour, at least once a day, or at least every two days (e.g., once a day).

[0057] Additionally or alternatively, the method can be performed after a specific number of samples have been processed by an analyzer system including a mass spectrometer. For example, the method can be performed at least once for every 100 samples processed by the mass spectrometer (e.g., at least once for every 400 samples analyzed by the mass spectrometer or at least once for every 1000 samples analyzed by the mass spectrometer).

[0058] The mass axis inspection process continues with the mass axis inspection sample preparation step 203 .

[0059] This step can involve different actions.

[0060] In some examples, the analyzer system can mix different substances (eg, two or more substances in a mixture and optionally an additional adjuvant). For example, a sample preparation station (eg, a pipette) can be used to prepare a mixture of two or more substances.

[0061] In some cases, in any case, the materials required to prepare a mixture of two or more substances may be present in the analyzer system. For example, in some examples, an internal standard (or its components), other types of standards, or quality control samples may be used to prepare the mixture. Other materials present in the analyzer system may be used in other examples. In these cases, additional consumables may not be required to perform the mass axis inspection technology of the present disclosure. It is only necessary to know the components of the materials used to ensure that the mass axis inspection process can be performed.

[0062] In other examples, a mass axis check sample (e.g., a mixture of two or more substances or any precursors of the mixture) can be provided to the analyzer system. For example, a pre-prepared mass axis check sample can be provided to the analyzer system. The mixture can be contained in any suitable container and stored in a corresponding storage area of ​​the automated analyzer.

[0063] exist Figure 2 In one example, the mass axis check sample preparation step is performed after a trigger event occurs. In other examples, the automated analyzer may proactively or at regular intervals prepare a mass axis check sample (eg, a mixture of the two or more substances) for use once a trigger event occurs.

[0064] Additional aspects of the composition of a mass axis inspection sample (e.g., a mixture of two or more substances) will be discussed next. In some examples, it is believed that at least two substances having peaks with different m / z ratios are required to detect the calibration state of the mass axis. However, in some examples, the mixture may include three or more or four or more different substances that span the measurement range of the mass spectrometer. For example, if three substances are used, the peaks evaluated for the first substance and the second substance may be located at the extremes of the measurement range (e.g., within 10% of the minimum / maximum m / z ratio of the measurement range). The peak of the third substance may be located in the middle of the measurement range (e.g., at an m / z ratio between 40% and 60% of the measurement range).

[0065] In general, a mass axis inspection sample can include any substance having peaks at m / z ratios suitable to span a particular measurement range.

[0066] In other examples, the mass axis inspection sample may also include a single substance that can be used to inspect the at least two mass axis points. For example, the single substance can be fragmented into two or more suitable fragments (i.e., fragments having different m / z values) in a mass spectrometer, and these fragments provide measurement data at the at least two mass axis points. Those skilled in the art will appreciate that a substance can be fragmented into different m / z values ​​that span the full m / z measurement range of a mass spectrometer.

[0067] In other examples, the mass axis inspection sample may include one or more substances selected to form clusters at different m / z values ​​by a combination of ions or atoms or molecules of a chemical species (e.g., in combination with a second species) in a mass spectrometer to provide the at least two mass axis points. The mass spectrum obtained by tandem mass spectrometry of the cluster ions can be characterized by a base peak having a molecular magic number that is less than and closest to the number of molecules in the precursor ion. Under appropriate ESI conditions, clusters covering a predetermined m / z range can be recorded.

[0068] In some examples, the prepared mass axis inspection sample is injected into a chromatograph for chromatographic separation 205. In particular, the chromatograph can be a liquid chromatography (LC) device. Figure 9 Exemplary LC devices that may be used with the presently disclosed techniques are discussed.

[0069] In some examples, other separation techniques besides chromatography can be used to separate substances. In other examples, (chromatographic) separation can be omitted entirely. For example, if the mass axis check sample (e.g., a mixture of two or more substances) is present in a sufficiently concentrated form, the mass axis check sample can be provided directly to the mass spectrometer without undergoing a separation step.

[0070] However, in many cases, it may be necessary and / or useful to process the mass axis check sample in a combination of a separation device (e.g., an LC device) and a mass spectrometer. Generally speaking, the techniques of the present disclosure may include processing a mass axis check sample (e.g., a mixture of two or more different substances) in a single chromatographic run prior to performing the steps of multiple full-scan mode mass spectrometry measurements as described herein, for example, to separate substances contained in the mass axis check sample.

[0071] return Figure 2 , the separation process can separate the mixture of two or more substances in time. For example, a first retention time (RT1) can be provided for a first substance ("Analyte 1"), a second retention time (RT2) can be provided for a second substance ("Analyte 2"), and a yth retention time (RT3) can be provided for a yth substance ("Analyte Y"). y ).

[0072] The disclosed techniques may include defining a measurement window for each of the separated substances. For each substance, the measurement window may be a separate and predefined measurement window. For example, each measurement window may have a duration of less than 30 seconds, optionally less than 20 seconds.

[0073] For each of the (separated) species, 207 different types of full scan mode mass spectrometry measurements can be performed. This will then be combined Figure 3 Discuss in more detail.

[0074] Figure 3 Depicted are three sets (i.e., multiplexed) of full-scan mode mass spectrometry measurements 301a, 301b, and 301c, each of which carries three different separated species. Generally speaking, the techniques of this disclosure can be directed to performing any type of full-scan mode mass spectrometry measurement on different species of a mass axis inspection sample. In some examples, the same set of measurements is performed on each of the (separated) species. In other examples, different types of mass spectrometry measurements are performed on different species of different species in a mixture.

[0075] In particular, the different measurements may be selected from a list comprising: 1) measurements in negative mode, 2) measurements in positive mode, 3) measurements on a specific mass filter of a mass spectrometer, 4) measurements at different scan speeds and 5) measurements at different scan resolutions.

[0076] For example, the different measurements may include measurements in positive and negative modes for examining a particular species of the sample on the mass axis.

[0077] Additionally or alternatively, the different measurements may include measurements on the Q1 mass filter and the Q3 mass filter (of the tandem mass spectrometer) for the particular substance.

[0078] In some examples, the measurement range of the MS measurement may be relatively small. For example, the measurement range of the MS measurement may be narrower than 30 amu, optionally lower than 10 amu, and further optionally narrower than 2 amu.

[0079] The process may include different optional pre-processing steps 303a, 303b, 303. For example, the method may include averaging multiple scans and / or smoothing operations.

[0080] In this manner, mass spectrometry raw data 305 is generated for each of the at least two mass axis points. This raw data 305 is then processed to determine whether the mass axis state of the mass spectrometer is within specification or out of specification. Additional aspects of this step will be discussed in subsequent sections. Figure 4 Have a discussion.

[0081] In the step of evaluating at least one peak in the measurement data of each of the at least two mass axis points, the raw data obtained in the mass spectrometry measurement can be automatically processed in different ways to obtain at least one measurement parameter for each of the at least two mass axis points.

[0082] For example, evaluating at least one peak in the measurement data of each of the at least two mass axis points may include fitting the at least one peak in the measurement data of each of the at least two mass axis points to obtain the at least one measurement parameter of each of the at least two mass axis points. For example, a single peak may be evaluated for each of the at least two mass axis points. In other examples, two peaks or more than two peaks may be evaluated.

[0083] exist Figure 4In the present invention, the evaluation of at least one peak includes an automated peak identification process and an automated peak fitting 401. This step may include any suitable numerical peak finding and fitting procedure. For example, a predetermined set of m / z ratios may be used for the peak to be found. The predetermined m / z ratios may be retrieved from a database 405 storing this data for use in the peak identification and peak fitting process.

[0084] In a further step, at least one measurement parameter of each of the at least two mass axis points is obtained 403. This may include automated peak feature analysis.

[0085] The measurement parameters (eg, peak characteristics) may include one or more of peak position, peak width, peak-baseline separation, and peak shape. The measurement parameters (eg, peak characteristics) will be discussed in more detail below in conjunction with FIG.

[0086] In some examples, more than one parameter is obtained for each peak (or for some peaks).For example, the at least one measured parameter includes peak position and peak width.

[0087] Once the at least one measurement parameter (eg, peak characteristics) has been obtained, it may be determined whether the mass axis condition is out of specification 407 .

[0088] This determination involves comparing the at least one measured parameter of each of the at least two mass axis points with corresponding reference data. For example, reference data for the measured parameter (peak characteristic) can be obtained from database 405. In some examples, database 405 includes theoretical values ​​of the measured parameter (peak characteristic). In other examples, database 405 includes measured reference values ​​of the measured parameter (peak characteristic).

[0089] Additionally, database 405 may include boundaries for reference data that define deviations from a value that is still considered acceptable (eg, theoretical).

[0090] The reference values ​​and boundaries can be used in the comparison step to determine whether a particular measurement (peak feature) is within an acceptable range. If one or more (or two or more) of the measurements (peak features) are not within the acceptable range, then the quality axis can be determined to be out of specification.

[0091] However, the comparison of the at least one measured parameter of each of the at least two mass pivot points with the corresponding reference data can also be performed in different ways. For example, a boundary around the reference value can be determined dynamically (e.g., without fixed boundary values). In addition, a variety of different comparison metrics can be used. For example, a relative deviation or an absolute deviation from the reference value can be evaluated. In other examples, an acceptance range for the measured value (peak feature) can be directly defined. It is also possible to dynamically generate and / or update the reference data.

[0092] In some examples, a binary decision is taken (e.g., "within specification" or "out of specification"). In this case, if the mass axis is within specification, normal operation of the analyzer system including the mass spectrometer can be restored 411. If the mass axis is out of specification, countermeasures can be triggered 413. Generally speaking, this can involve triggering a mass axis adjustment procedure including separate measurements. In addition or alternatively, maintenance and / or repair operations can be triggered. In some examples, these countermeasures can be automatically performed by the analyzer system. However, in other cases, the countermeasures require intervention by an operator and / or service personnel. In these cases, the analyzer system can send a message and / or issue a warning to the operator and / or service personnel. For example, a warning and / or error message can be issued on a (possibly remote) user interface of the automated analyzer.

[0093] In other examples, binary decisions can include triggering other actions besides those described above. For example, preventive maintenance (e.g., mass axis adjustment) can be scheduled or triggered. This may require different definitions of boundaries to detect when a measurement value (peak feature) is out of specification.

[0094] In other examples, the determining step may include distinguishing between three categories, or three or more categories, and triggering different responses (or non-responses).

[0095] like Figure 4 As shown, an additional category to the two aforementioned categories could be that the quality axis is within specification but within a predetermined distance of an out-of-specification threshold. In other words, the quality axis is close to being out of specification. In this case, a specialized response can be triggered. For example, the automated analyzer can schedule preventive maintenance operations. In this way, analyzer system downtime can be reduced by preventing more serious errors and / or scheduling maintenance operations at convenient times (e.g., when the automated analyzer is off duty).

[0096] In still different examples, more than three categories of reactions may be triggered (eg, the different reactions discussed herein).

[0097] Additionally, the short quality axis inspection procedure of the present disclosure facilitates this flexibility in triggering reactions.When using prior art techniques, the long duration and / or complexity of the procedure may not allow for regular inspection of quality axis conditions to schedule predictive maintenance operations.

[0098] In the previous sections, several aspects of the quality shaft inspection technology of the present disclosure have been elaborated in detail. In the following sections, further details about the measurement results and data processing according to the present disclosure will be discussed.

[0099] Example measurement and data processing results

[0100] Figure 5 、 Figure 6 、 Figure 7 8 show exemplary measurement and evaluation results obtained when using the techniques of the present disclosure. Figure 5 、 Figure 6 、 Figure 7 and Figure 8 follows Figures 2 to 4 Mass spectrometry steps for an exemplary mass axis inspection technique are shown.

[0101] As previously mentioned, a mass axis inspection sample (e.g., a mixture of two or more substances) can undergo separation (and enrichment) during LC ( Figure 5 "1. LC separation of multiple analytes" in [1.

[0102] exist Figure 5 In FIG8 , an exemplary mixture includes five different substances or analytes: testosterone, tacrolimus, cyclosporin A, cortisol, and valproic acid. However, this set of substances or analytes is merely exemplary. As described above, a greater or lesser number of substances that span the measurement range of the mass spectrometer can be used. In addition, exemplary substances that can be used in a mixture of two or more substances are listed above.

[0103] like Figure 5 As shown, mass spectrometry measurements were performed in positive mode (the middle curve shows the chromatogram of the positive mode analyte) and negative mode (the lower curve shows the chromatogram of the negative mode analyte). As can be seen, the different substances in the mixture were separated during the LC process. The upper curve shows the total ion count signal of the exemplary mixture, indicating the signal of all substances or analytes contained in the mixture.

[0104] Figure 6 The three peaks of the chromatogram of the positive mode analyte or substance that can be found at different retention times are shown. Now, the technique proceeds to perform multiple mass spectrometric measurements for each of the analytes or substances being separated in the mixture. In other words, during a measurement window of a predetermined size (in Figure 6 Again, different measurements can be performed during the measurement window (e.g., using different mass filters, scan speeds, and scan resolutions). This could include performing a full scan mass spectrometry measurement on a specific analyte in a time window targeted at the specific analyte (e.g., in Figure 6 Switching between different measurement modes of the mass spectrometer (at a retention time between 40 s and 55 s for the analyte or substance in the middle diagram).

[0105] Figure 7 Shown Figure 6 Example mass spectrometry results for three analytes of the (selected) chromatogram of . It can be seen that the mass spectrometry measurement was performed in full scan mode with a relatively small measurement range. Figure 7In the example of FIG, the measurement range for each analyte or substance is 20 amu. However, as described above, other measurement ranges (e.g., 10 amu or less or 3 amu or less) may be used in other examples. Figure 7 The measurement data depicted in the above is combined with Figure 3 Example of the mass spectrometry raw data in question. As can be seen, multiple peaks can be resolved for each of the three analyte species.

[0106] These peaks are then analyzed in an automated data processing step (as described above in conjunction with Figure 4 discussed). Figure 5 The results of this process for the example of FIG8 are depicted in FIG. Figure 8a and Figure 8b middle.

[0107] Figure 8a An exemplary group of measurements that have been processed using automated peak identification and fitting techniques according to the present disclosure is shown. Figure 8a Shown are different measurements for each substance or analyte in a substance mixture or analyte across the mass spectrometer measurement range. It can be seen that the exemplary mass axis inspection technique includes measurements in positive and negative modes for some analytes or substances (e.g., cyclosporin A). In addition, the different measurements include measurements performed with different mass filters (e.g., Q1 and Q3 mass filters of a tandem mass spectrometer) for some analytes or substances (e.g., testosterone, tacrolimus, and cortisol). In addition, for some analytes, measurements in negative and positive modes for different mass filters are performed (cyclosporin A).

[0108] As described above, when using mass axis inspection techniques according to the present disclosure, other types of measurements can be performed for the different analytes or substances. For example, the different measurements can include measurements performed at different scan speeds or resolutions. In addition, a different number of measurements (e.g., three or more different measurements) can be performed for one or more of the analytes or substances in the mixture.

[0109] return Figure 8a The peak fitting and peak identification techniques can be configured to identify and fit a single peak in the measurement results (for each measurement and each analyte or substance). For the example of a measurement in positive mode and in the Q1 mass filter for tacrolimus, a peak at an m / z ratio of approximately 826.5 was identified and fitted.

[0110] Peak identification procedures may include the use of reference data (e.g., theoretical values ​​of peaks for a substance or analyte in a mixture). Peak fitting may include any known digital signal processing technique. For example, in some examples, a single Gaussian function may be used as the fitting function.

[0111] exist Figure 8a In the example shown, each measurement is fitted with a single peak. In other examples, multiple peaks can be identified and fitted.

[0112] After the peaks have been identified and fitted (one or more peaks per measurement), the measurement parameters (peak parameters) are determined (again in an automated process). Figure 8b An exemplary set of peak parameters determined for measurements in positive mode and in a Q1 mass filter for tacrolimus is shown. In this example, peak width ("resolution") (e.g., FWHM peak width), position (e.g., m / z position of the peak), peak shape parameters (e.g., determined by evaluating the residuals of the fitting process), and baseline separation parameters can be determined.

[0113] As mentioned above, further and / or different measurement parameters (and in particular peak parameters) may be determined in other examples.

[0114] In a further step, the measurement parameters thus determined are compared with reference data to determine whether the mass axis conditions of the mass spectrometer are out of specification.

[0115] Analyzer details

[0116] The present disclosure also relates to an analyzer system comprising a mass spectrometer (MS), optionally connected to two or more liquid chromatography (LC) streams, the analyzer configured to perform the steps of the mass axis inspection technique of the present disclosure.

[0117] It will then be combined Figure 9 An exemplary automated analyzer system including a mass spectrometer according to the present disclosure is discussed. Figure 9 1 is shown as part of an automated analyzer system 100. However, the automated analyzer system of the present disclosure may also include only Figure 9 A subset of the different modules depicted in .

[0118] The automated analyzer system 100 includes a sample preparation station 50 for automated pretreatment and preparation of a sample 10 containing an analyte of interest. The sample preparation station 50 may include a magnetic bead processing unit 51 for processing the sample with magnetic beads carrying analyte and / or matrix selective groups.

[0119] The sample preparation station 50 may be configured to perform the process of preparing a mass shaft inspection sample of the present disclosure.

[0120] In particular, the magnetic bead processing unit may include at least one magnetic or electromagnetic workstation for receiving at least one reaction vessel and for manipulating the magnetic beads added to one or more samples contained therein. The magnetic bead processing unit may further include a mixing mechanism for mixing the fluid and / or resuspending the magnetic beads in the reaction vessel, for example by shaking or stirring the reaction vessel, for example by an eccentric rotation mechanism.

[0121] Alternatively, the bead processing unit can be a flow-through system in which the magnetic beads are captured in a flow or capillary flow-through device. According to this example, the capture, washing and release of the analyte can be accomplished by repeatedly magnetically capturing and releasing the beads in the flow-through stream.

[0122] The term "bead" does not necessarily refer to a spherical shape, but rather refers to microparticles having an average size in the nanometer or micrometer range and having any possible shape. The beads may be supermagnetic beads or paramagnetic beads, in particular beads comprising an Fe3+ core.

[0123] Non-magnetic beads can also be used. In this case, capture and release can be performed based on filtration. The sample preparation station can further include one or more pipetting devices or fluid transport devices for adding / removing fluids, such as samples, reagents, washing fluids, and suspending fluids, to / from the reaction vessel.

[0124] The sample preparation station may further include a reaction vessel transport mechanism ( Figure 9 not shown).

[0125] Alternatively or in addition to magnetic bead treatment, other enrichment techniques can be used, for example, protein precipitation followed by centrifugation, column-based solid phase extraction, pipette tip-based solid phase extraction, liquid extraction, affinity-based extraction (immunoadsorption, molecular imprinting, aptamers, etc.).

[0126] The clinical diagnostic system 100 further comprises a liquid chromatography (LC) separation station 60 comprising a plurality of LC streams Cl-n, C'l-n.

[0127] Liquid chromatography (LC) separation station 60 can be an analytical device or a module or unit within an analytical device that is designed to subject a prepared sample to chromatographic separation, for example, to separate the target analyte from matrix components, such as residual matrix components or other potentially interfering substances that may interfere with subsequent detection, such as mass spectrometry, after sample preparation, and / or to separate the target analytes from each other to enable their individual detection. In some examples, the LC separation station can be an intermediate analytical device or a module or unit within an analytical device that is designed to prepare a sample for mass spectrometry analysis and / or transfer the prepared sample to a mass spectrometer.

[0128] According to certain examples of the present disclosure, the LC separation station includes at least one faster LC stream with a shorter cycle time and at least one slower LC stream with a longer cycle time. However, the LC separation station may alternatively include at least two faster LC streams without a slower LC stream, or include at least two slower LC streams without a faster LC stream. "Cycle time" refers to the time required from the input (injection) of a sample into an LC stream until the same LC stream is ready to accept another sample input. In other words, the cycle time refers to the shortest time that passes between two consecutive sample inputs in the same LC stream under predetermined conditions, and can be measured in seconds. The cycle time includes the injection time, the separation time before eluting the last target analyte, and the re-equilibration time to prepare the chromatographic column for a new injection.

[0129] The terms "faster" and "slower" with reference to LC flows are only relative terms used to compare different LC flows in the same LC separation station with each other. In particular, these terms relate to the duration of the cycle time and not necessarily to the resolving power of the LC flow.

[0130] Typically, the LC separation station further comprises a sufficient number of pumps, for example binary pumps if an elution gradient is required, and a number of switching valves.

[0131] Furthermore, since the LC separation station comprises multiple LC streams, it is advantageous that the LC eluates from different LC streams are output in an interleaved manner rather than simultaneously, so that the LC eluate outputs can be detected sequentially, for example, by a single common detector, and better distinguished from each other after adopting a multiplexing approach.

[0132] The term "LC eluate" is used herein to indicate a portion of the eluate comprising at least one analyte of interest.

[0133] In conventional practice, depending on the number and type of incoming samples and the corresponding analysis order, one LC flow may be required rather than another, for example, a slower LC flow may be required rather than a faster LC flow, or vice versa, one type of column may be required in one LC flow rather than another type of column in another LC flow. Therefore, it is possible that some LC flows are used more frequently than others.

[0134] Different degrees of flexibility may also be achieved based on the number and type of LC flows, for example based on the number and type of faster and slower LC flows, respectively.

[0135] exist Figure 9 In the example of , Cl-n is a faster LC flow with a shorter cycle time, and C'l-n is a slower LC flow (eg, with a longer cycle time), and where n can be any integer equal to or greater than 1.

[0136] Thus, the LC separation station 60 may include at least one faster LC stream Cl having a shorter cycle time and at least one slower LC stream Cl having a longer cycle time. However, the LC separation station 60 may include a plurality of only faster LC streams Cl-n, where n is at least 2, or a plurality of only slower LC streams C'l-n, where n is at least 2. In this example, the LC separation station 60 includes two faster LC streams Cl-n having shorter cycle times, where n=2, and four slower LC streams C'l-n having longer cycle times, where n=4, where the relative lengths of the respective shorter and longer cycle times are given by Figure 9 The bars of different lengths representing the LC flows Cl-n and C'l-n are schematically represented (not to scale). The shorter cycle time can be, for example, between 10 seconds and 1 minute (e.g., 36 seconds), and this time defines the reference time period. The longer cycle time is n times the reference time period.

[0137] In addition, by selecting an LC column and setting the chromatographic conditions accordingly, the elution time window of the slower LC flow for eluting the analyte of interest is set to be the same as or shorter than the reference time period.

[0138] The faster LC streams Cl-n can be fast capture and elution online liquid chromatography streams, one of which includes, for example, a reverse phase column and the other includes, for example, a HILIC column. The slower LC streams C'l-n can be ultra-high performance liquid chromatography (UHPLC) streams, each including, for example, two reverse phase columns and two HILIC columns.

[0139] The slower LC flows may be the same as or different from each other, for example, one includes a HILIC column and the other includes a reversed phase (RP) column or a pentafluorophenyl (PFP) column, wherein the conditions are selected such that the cycle times of the different columns are the same. The faster LC flows may be the same as or different from each other, for example, one includes a HILIC column and the other includes a reversed phase (RP) column or a pentafluorophenyl (PFP) column, wherein the conditions are selected such that the cycle times of the different columns are the same.

[0140] According to one example, at least one faster LC flow is a capillary flow injection analysis (FIA) flow or a rapid capture and elution online liquid chromatography flow, and at least one slower LC flow is an ultra-high performance liquid chromatography (UHPLC) flow. In particular, depending on the target analyte, each prepared sample can be input into a faster LC flow or into a slower LC flow. For example, if the sample only requires analyte purification and concentration, the sample is input into a faster LC flow, such as FIA or a rapid capture and elution online liquid chromatography flow, because sufficient separation can be obtained in subsequent mass spectrometry analysis and / or other separation techniques. In this case, the stationary phase is selected so as to retain the target analyte, while any salts, buffers, detergents and other matrix components will not be retained and will be washed away. After this process, the analyte is usually eluted with a different mobile phase or solvent gradient, for example, in a backwash mode. Depending on the analyte, some analytes may be separated in some cases. On the other hand, if the analytes have the same mass (isobaric elements) and / or the product ion spectra overlap in multiple reaction monitoring (MRM), a wider chromatographic separation may be desirable when it comes to mass spectrometry. In this case, the sample is injected into a slower LC stream, such as a UHPLC stream.

[0141] The automated analyzer system 100 further includes a sample preparation / LC interface 70 for inputting the prepared sample into any one of the LC streams Cl-n, C'l-n.

[0142] The sample preparation / LC interface may be a module between the sample preparation station and the LC separation station, or a unit integrated in the sample preparation station or in the LC separation station or in a common component between the sample preparation station and the LC separation station.

[0143] The sample preparation / LC interface can include a container handling unit or a prepared sample receiving unit that can have any one or more of a holding function, a clamping function, and a transfer function. In some embodiments, the prepared sample receiving unit is a reusable well into which prepared samples are received one by one according to a prepared sample output sequence before being input into the LC stream, wherein the well can be washed between consecutive samples.

[0144] The sample preparation / LC interface can include a liquid handling unit to feed the prepared sample into any of the LC streams. The liquid handling unit can include any one or more of the following: a pipetting device, a pump, an autosampler, a flow injection device, and one or more switching valves, particularly at least one switching valve for switching between LC streams. In particular, the container handling unit and the liquid handling unit can be designed to allow any prepared sample to be randomly fed into any available LC stream.

[0145] At least for some samples, the combination of analyte enrichment and matrix depletion techniques may have the advantages of expanding the number of different analytes that can be extracted from the sample, avoiding unnecessary dilution, and more effectively removing the matrix.

[0146] The automated analyzer system 100 further includes a controller 80 configured to control the automated analyzer system.

[0147] The controller 80 may be configured to perform the steps of the mass axis inspection technique of the present disclosure. In particular, the controller may include an automated scheduler for scheduling mass spectrometry measurements of the present disclosure.

[0148] Additionally, the controller may be programmed to assign samples 10 to predefined sample preparation workflows, each workflow comprising a predefined sequence of sample preparation steps and requiring a predefined time for completion (depending on the analyte of interest).

[0149] In particular, the controller can collaborate with the scheduler to consider received analysis commands and a number of scheduled process operations associated with executing the analysis commands to determine when which sample must be prepared, and when which preparation steps must be performed for each sample. Because different types of samples and / or different analytes of interest contained in the same or different types of samples may require different preparation conditions, such as different reagents or different amounts of reagents, different volumes, different incubation times, different washing conditions, etc., preparing different samples may require different sample preparation workflows. Therefore, the controller is programmed to assign samples to predefined sample preparation workflows, each workflow comprising a predefined sequence of sample preparation steps, including, for example, different steps and / or a different number of steps, and requiring a predefined completion time, such as from a few minutes to several minutes.

[0150] Thus, the controller can schedule sample preparation for different samples in parallel or in an interleaved manner. By doing so in a logical manner, the controller schedules the use of the functional resources of the sample preparation station in order to improve efficiency while avoiding conflicts and maximizing throughput by preparing samples at a speed at which the prepared samples can be input into the LC separation station. This means that, instead of preparing a batch of samples in advance (which is of course possible), the controller can instruct the sample preparation station to prepare samples as needed or according to the processing capacity of the LC separation station, in particular according to the processing capacity of the individual LC streams, taking into account the incoming commands (e.g. priority commands), the preparation time, the required functional resource usage and in particular the availability of the LC stream for which the sample was intended when the sample preparation is completed. In particular, the controller can schedule the preparation of samples for inspection according to the quality axis of the present disclosure.

[0151] exist Figure 9In the example of FIG. 1 , the controller 80 is further programmed to allocate (pre-reserve) LC flows C1-n and C'1-n for each prepared sample according to the target analyte, and to plan an LC flow input sequence I1-n for inputting the prepared samples, which allows the target analytes from different LC flows C1-n and C'1-n to elute in non-overlapping LC eluate output sequences E1-n based on the expected elution time. Similarly, the controller 80 is further programmed to allocate (pre-reserve) LC flows C1-n and C'1-n for the mass axis check samples.

[0152] The controller 80 is further programmed to set up and initiate sample preparation initiation sequences S1-n that produce preparation sample output sequences P1-n that match the LC stream input sequences I1-n.

[0153] exist Figure 9 In the example, each sample in the sample preparation starting sequence S1-n, each sample in the sample preparation output sequence P1-n, each sample in the LC stream input sequence I1-n, and each LC eluate in the LC eluate output sequence E1-n are represented as segments in a sequence of non-overlapping adjacent segments, with each segment schematically representing a reference time period. Thus, each sequence is a sequence of reference time periods or time units, the length of which can be fixed and remain constant across different sequences. In particular, the shorter cycle time of a faster LC stream (e.g., 36 seconds) can be used as a reference time period.

[0154] The preparation of new samples in the sample preparation start sequence S1-n is started at a frequency of one sample per reference time period (i.e., every 36 seconds in this example), or at intervals separated by one or more reference time periods, which intervals are represented by blank segments in the sequence, during which no sample preparation is started. Furthermore, the preparation of samples in the prepared sample output sequence P1-n is completed at a frequency of one prepared sample per reference time period, or at intervals separated by one or more reference time periods, which intervals are represented by blank segments in the sequence, during which no sample preparation is completed. Furthermore, according to the LC stream input sequence 11-n, the prepared samples are input into the corresponding allocated LC stream at a frequency of one LC stream input per reference time period, or at intervals separated by one or more reference time periods, which intervals are represented by blank segments in the sequence, during which no LC stream input occurs.

[0155] In addition, the LC eluates in the LC eluate output sequences El-n are output at a frequency of one LC eluate per reference time period, or are output at intervals separated by one or more reference time periods, the intervals being represented by empty segments in the sequence in which no LC eluate is output.

[0156] The clinical diagnostic system 100 further includes a mass spectrometer (MS) 90 and an LC / MS interface 91 for connecting the LC separation station 60 to the mass spectrometer 90 .

[0157] According to one embodiment, the LC / MS interface includes an ionization source for generating charged analyte molecules (molecular ions) and transferring the charged analyte molecules into the gas phase. According to certain embodiments, the ionization source is an electrospray ionization (ESI) source, a heated electrospray ionization (HESI) source, an atmospheric pressure chemical ionization (APCI) source, an atmospheric pressure photoionization (APPI), or an atmospheric pressure laser ionization (APLI) source. However, the LC / MS interface may include a dual ionization source, such as both an ESI and an APCI source, or a modular, exchangeable ionization source. Such ionization sources are known in the art and are not further described herein.

[0158] To optimize the ionization conditions, the solvent composition can be adjusted by adding a supplemental flow, preferably directly before the ion source, to adjust the pH, salt, buffer or organic content.

[0159] In one example, all LC streams can be alternately connected to the ionization source, and a controller controls valve switching according to the LC eluate output sequence.

[0160] In one embodiment, the mass spectrometer is a rapid scanning mass spectrometer. For example, the mass spectrometer can be a tandem mass spectrometer that selects a parent molecular ion, generates fragments by collision-induced fragmentation, and separates the fragments or product ions according to their mass-to-charge (m / z) ratio. The mass spectrometer can be a triple quadrupole mass spectrometer as known in the art.

[0161] According to an example, the LC / MS interface further includes an ion migration module between the ion source and the mass spectrometer. According to an example, the ion migration module is a high-field asymmetric waveform ion mobility spectrometer (FAIMS) module, as also known in the art, and can realize the separation of molecular ions in the gas phase within milliseconds, including ions of the same mass. The ion migration gas phase separation before mass spectrometry can compensate for insufficient chromatographic separation, for example, due to isobaric interference, particularly for LC eluates from at least one faster LC flow. In addition, the ion migration interface for mass spectrometer can reduce overall background signals by preventing background ions and other nonspecific ions from entering the mass spectrometer. According to an example, the controller is further programmed to set the ionization source input sequence. The term "ionization source input sequence" refers to the order in which the LC eluate is input into the ionization source. Typically, the ionization source input sequence corresponds to the LC eluate output sequence. However, by using, for example, a bypass flow or a flow of different lengths or changing the flow rate, the ionization source input sequence can also be changed. This allows the controller to have greater flexibility when planning the LC flow input sequence.

[0162] In some examples, LC eluates in the LC eluate output sequence are input to the ionization source at a frequency of one LC eluate per reference time period, or at intervals separated by one or more reference time periods. This means that, during a reference time period with ionization source input, there may be empty reference time periods in which no LC eluate is input to the ionization source within the same timeline comprised of a series of reference time periods. The controller can be programmed to ensure that only one LC eluate is input to the ionization source per reference time period by considering the LC stream input sequence and the LC eluate output sequence and controlling valve switching accordingly.

[0163] exist Figure 9 In the example of , LC / MS interface 91 includes an ionization source 92 and an ion mobility module 95 between ionization source 92 and mass spectrometer 95. Ion mobility module 95 is a high field asymmetric waveform ion mobility spectrometry (FAIMS) module. Mass spectrometer 90 is a tandem mass spectrometer, and in particular a triple quadrupole mass spectrometer, capable of multiple reaction monitoring (MRM).

[0164] LC streams C1-n and C'1-n are alternately connected to the LC / MS interface 91, and the controller 80 controls the valve switch 61 according to the LC eluate output sequence E1-n so that one LC eluate is input into the ionization source 92 at a time. Specifically, according to the LC eluate output sequence E1-n, the LC eluates in the LC eluate output sequence E1-n are input into the ionization source 92 at a frequency of one LC eluate per reference time period or at intervals separated by one or more reference time periods. The ionization source 92 is a dual ionization source comprising an ESI source 93 and an APCI source 94. Depending on the LC eluates in the LC eluate output sequence E1-n and the target analytes contained therein, the controller 80 can select the most appropriate of the two ionization sources 93 and 94. When setting the sample preparation starting sequence S1-n, the controller 80 can also group the samples together according to the ionization sources 93 and 94 (place them adjacent to each other in the sequence) to prevent frequent switching between the ionization sources 93 and 94. Ionization source switching may be planned, for example, during one or more null reference time periods.

[0165] Computer implementation

[0166] The present disclosure also relates to a computer system configured to perform a technique for checking the validity of a mass axis calibration of a mass spectrometer.

[0167] In some examples, the computer system may be the controller of the analyzer (or a portion thereof). However, in other examples, the computer system may only be connected to the analyzer via a network and may not be part of the analyzer's controller. For example, the computer system may be a hospital or laboratory management system, or a computer system of a supplier or service provider of the analyzer.

[0168] The computing system of the present disclosure is not limited to a specific software or hardware configuration. As long as the software or hardware configuration can perform the steps of checking the validity of the mass axis calibration of the mass spectrometer according to the present disclosure, the computing system may have such software or hardware configuration.

[0169] The present disclosure also relates to a computer-readable medium having instructions stored thereon, which, when executed by a computer system, prompt the computer system to perform the steps of checking the validity of the mass axis calibration of a mass spectrometer according to the present disclosure.

[0170] Further disclosed and proposed is a computer program comprising computer-executable instructions for carrying out the method according to the present disclosure in one or more of the embodiments appended hereto when the program is executed on a computer or a computer network. In particular, the computer program can be stored on a computer-readable data carrier. Thus, in particular, one, more than one, or even all of the method steps as disclosed herein can be carried out by using a computer or a computer network, preferably by using the computer program.

[0171] Further disclosed and proposed is a computer program product with program code, so that when the program is executed on a computer or a computer network, the method according to the present disclosure is performed in one or more embodiments attached hereto. Specifically, the program code can be stored on a computer-readable data carrier.

[0172] Furthermore, a data carrier having a data structure stored thereon is disclosed and proposed, which, after being loaded into a computer or a computer network, such as after being loaded into a working memory or main memory of the computer or the computer network, can perform a method according to one or more embodiments disclosed herein.

[0173] Further disclosed and proposed is a computer program product having program code stored on a machine-readable carrier, so that when the program is executed on a computer or computer network, the method according to one or more embodiments disclosed herein is performed. As used herein, a computer program product refers to a program that is a tradable product. The product can generally be present in any format (such as paper format) or on a computer-readable data carrier. In particular, the computer program product can be distributed over a data network.

[0174] Further disclosed and proposed is a modulated data signal containing instructions readable by a computer system or computer network for performing a method according to one or more embodiments disclosed herein.

[0175] With reference to the computer-implemented aspects of the present disclosure, one or more method steps or even all method steps of the methods according to one or more embodiments disclosed herein can be performed using a computer or a computer network. Thus, generally speaking, any method step including providing and / or processing data can be performed using a computer or a computer network. Generally speaking, these method steps can include any method steps other than those that typically require manual work (such as providing samples and / or performing certain aspects of measurements).

[0176] Further disclosed and proposed is a computer or a computer network comprising at least one processor, wherein the processor is adapted to execute the method according to one of the embodiments described in this specification.

[0177] A computer-loadable data structure is further disclosed and proposed, which is suitable for performing a method according to one of the embodiments described in this specification when the data structure is executed on a computer.

[0178] A storage medium is further disclosed and proposed, wherein a data structure is stored on the storage medium and wherein the data structure, after being loaded into a main storage device and / or a working storage device of a computer or a computer network, is suitable for executing a method according to one of the embodiments described in this specification.

[0179] Further aspects

[0180] In the previous sections, various aspects of the disclosed technique for checking the validity of the mass axis calibration of a mass spectrometer have been discussed. In addition, the disclosed checking technique may also be performed according to the following aspects:

[0181] 1. A method for checking the validity of a mass axis calibration of a mass spectrometer (MS) of an analyzer system, the method comprising:

[0182] obtaining a mass axis inspection sample spanning a predetermined m / z measurement range of the mass spectrometer;

[0183] Automatic processing of the quality axis inspection sample, including:

[0184] performing a plurality of full scan mode MS measurements of different types on at least two mass axis points within the predetermined m / z measurement range of the MS using the MS to obtain measurement data,

[0185] wherein the different types include at least a first full scan MS measurement in positive mode and a second measurement in negative mode or at least a first full scan measurement of a first mass filter of the mass spectrometer and a second full scan mode of a second mass filter of the mass spectrometer; wherein the plurality of different full scan MS measurements are selected such that a maximum measurement time in the mass spectrometer is less than 5 minutes;

[0186] comparing the measurement data of each of the at least two mass axis points with corresponding reference data;

[0187] A determination is made based on the results of the comparing step whether the mass axis calibration condition is out of specification.

[0188] 2. The method according to aspect 1, wherein the quality axis inspection sample comprises:

[0189] a mixture of two or more different species spanning the full m / z measurement range of the mass spectrometer, wherein the at least two mass axis points are provided by different species in the mixture; or

[0190] a single species capable of fragmenting into two or more fragments having different m / z values, wherein the at least two mass axis points are provided by different fragments; or

[0191] One or more species selected to form clusters of ions or atoms or molecules that pass through the mass spectrometer at different m / z values ​​to provide the at least two mass axis points.

[0192] 3. The method according to aspect 1 or aspect 2, further comprising scheduling the processing of the quality axis check sample in an automated scheduling process of the analyzer system, preferably wherein the maximum measurement time is less than 2 minutes.

[0193] 4. The method according to any one of aspects 1 to 3, further comprising:

[0194] Prior to the step of performing a plurality of full scan mode mass spectrometry measurements, the mass axis inspection sample is processed in a single chromatographic run to separate two or more substances contained in the mass axis inspection sample.

[0195] 5. A method according to any one of aspects 3 to 4 above, wherein scheduling the processing of the mass axis inspection sample in an automated scheduling process includes minimizing the impact on the throughput of the mass spectrometer or an analyzer including the mass spectrometer.

[0196] 6. The method according to any one of the preceding aspects, wherein the mass axis inspection sample comprises fragments or clusters of molecules with different m / z values ​​to cover the m / z measurement range of the mass spectrometer.

[0197] 7. The method according to any one of aspects 1 to 6, wherein comparing the measurement data of each of the at least two mass axis points with corresponding reference data comprises:

[0198] evaluating at least one peak in the measurement data of each of the mass axis points to obtain at least one measurement parameter of each of the at least two mass axis points;

[0199] comparing the at least one measured parameter of each of the at least two mass axis points with corresponding reference data; and

[0200] A determination is made based on the results of the comparing step whether the mass axis calibration condition is out of specification.

[0201] 8. The method of aspect 7, wherein the at least one measurement parameter comprises one or more of peak position, peak width, peak baseline separation, and peak shape.

[0202] 9. The method of clause 8, wherein the at least one measurement parameter comprises peak position and peak width.

[0203] 10. The method according to any one of aspects 1 to 9, further comprising:

[0204] A mass axis adjustment procedure including separate measurements is scheduled or triggered if the determining step concludes that the mass axis calibration condition is out of specification, or operation of the mass spectrometer is resumed if the mass axis calibration condition is not out of specification.

[0205] 11. A method according to any one of aspects 1 to 10, wherein comparing the measurement data of each of the at least two mass axis points with corresponding reference data includes: fitting at least one peak in the measurement data of each of the at least two mass axis points to obtain at least one measurement parameter of each of the at least two mass axis points.

[0206] 12. A method according to any one of aspects 1 to 11, wherein the maximum measurement time is selected as the duration of the measurement window of the production sample of the mass spectrometer, or is selected as an integer multiple of the duration of the measurement window of the production sample of the mass spectrometer.

[0207] 13. The method according to any one of the preceding aspects 1 to 12, wherein the maximum measurement time is less than 2 minutes.

[0208] 14. The method according to any one of the preceding aspects 1 to 13, wherein the method of checking the validity of the mass axis calibration of the mass spectrometer comprises at least 50 measurement cycles with a mass interval of at least 2 amu.

[0209] 15. The method according to any one of the preceding aspects 1 to 14, wherein the method is repeatedly performed during a production mode of the mass spectrometer,

[0210] Optionally wherein the method is performed at least once per day or at least once every 400 samples analyzed by the mass spectrometer.

[0211] 16. The method according to any one of the preceding aspects 1 to 15, wherein the method is performed in one or more of the following situations:

[0212] - during a quality control routine of the mass spectrometer or of the analyzer comprising the mass spectrometer;

[0213] - during a periodic instrument inspection of the mass spectrometer or the analyzer comprising the mass spectrometer;

[0214] - during a start-up procedure of the mass spectrometer or of the analyzer comprising the mass spectrometer;

[0215] - regularly during downtime of the mass spectrometer or the analyzer comprising the mass spectrometer;

[0216] - after a repair or maintenance operation of the mass spectrometer or of the analyzer comprising the mass spectrometer.

[0217] 17. The method according to any one of aspects 1 to 16, wherein the method is performed when a triggering event occurs, the triggering event comprising one or more of the following:

[0218] - a change in the state of the mass spectrometer or of the analyzer system comprising the mass spectrometer,

[0219] a monitored parameter of the mass spectrometer or of the analyzer system comprising the mass spectrometer assumes a specific value or exceeds a specific threshold value;

[0220] - monitored parameters of the environment of the mass spectrometer; or

[0221] - Detection of errors in the mass spectrometer or in the analyzer system comprising the mass spectrometer.

[0222] 18. The method according to any one of the preceding aspects 1 to 17, wherein performing mass spectrometry to obtain measurement data for each of the at least two mass axis points comprises using a separate and predefined measurement range for each mass axis point.

[0223] 19. The method of aspect 18, wherein the measurement range is narrower than 10 amu, optionally narrower than 2 amu.

[0224] 20. The method according to any one of the preceding aspects 1 to 19, wherein the m / z measurement range of the mass spectrometer is the maximum m / z measurement range provided by the mass spectrometer.

[0225] 21. The method according to any one of the preceding aspects 1 to 20, wherein the m / z measurement range of the mass spectrometer spans 10 amu to 5000 amu, optionally 15 amu to 3000 amu.

[0226] 22. A method according to any one of the preceding aspects 1 to 21, wherein the m / z measurement range of the mass spectrometer is defined by a plurality of analytes and / or clusters to be measured by the mass spectrometer, and the m / z measurement range spans the m / z range of the plurality of analytes to be measured by the mass spectrometer from the analyte requiring the lowest m / z ratio to the analyte requiring the highest m / z ratio.

[0227] 23. The method according to any one of the preceding aspects 1 to 22, wherein comparing the measurement data comprises averaging a plurality of mass spectrometer measurement cycles.

[0228] 24. A method according to aspect 23, wherein the results of the multiple full-scan mode MS measurements of the different types are combined to obtain the measurement data for each of the at least two m / z points, and optionally wherein the results of the multiple full-scan mode MS measurements of the different types are averaged to obtain the measurement data for each of the at least two m / z points.

[0229] 25. The method according to any one of the preceding aspects 1 to 24, wherein the plurality of full scan mode MS measurements of different types further comprises one or more measurements selected from a list consisting of:

[0230] Measurement in negative mode;

[0231] Measurement in positive mode;

[0232] Measurement of a specific mass filter of said mass spectrometer;

[0233] Measurements at different scanning speeds;

[0234] Measurements at different scanning resolutions;

[0235] measurements performed using different ion sources of the analyzer system; and

[0236] Measurements performed using different detectors of the analyzer system.

[0237] 26. A method according to any one of the preceding aspects 1 to 25, wherein the analyzer system processes the sample in a clocked manner, and wherein the method for checking the validity of the mass axis calibration of the mass spectrometer of the analyzer system has a duration of one clock cycle or an integer multiple of one clock cycle.

[0238] 27. A method according to any one of the preceding aspects 1 to 26, wherein if the step of determining whether the mass axis calibration condition is out of specification concludes that the mass axis calibration condition is within specification but within a predetermined distance from an out of specification threshold, then preventive maintenance is scheduled.

[0239] 28. A computer system configured to perform the steps of the method of any one of aspects 1 to 27.

[0240] 29. The computer system of aspect 28, wherein the computer system is a controller of an analyzer system including a mass spectrometer.

[0241] 30. The computer system of aspect 29, wherein the analyzer system is a clinical or diagnostic analyzer system.

[0242] 31. A computer-readable medium comprising instructions stored thereon, which, when executed by a computer system comprising a mass spectrometer, prompt the computer system to perform the steps of any of the methods of aspects 1 to 27.

Claims

1. A method for checking the validity of a mass axis calibration of a mass spectrometer (MS) of an analyzer system, wherein the analyzer system including the mass spectrometer operates based on a specific clock, the specific clock being a predetermined time period during which the mass spectrometer processes a specific sample in a single measurement process, the method comprising: obtaining a mass axis inspection sample spanning a predetermined m / z measurement range of the mass spectrometer; Automatic processing of the quality axis inspection sample, including: performing a plurality of full scan mode MS measurements of different types on at least two mass axis points within the predetermined m / z measurement range of the MS using the MS to obtain measurement data, wherein the different types include at least a first full scan MS measurement in a positive mode and a second measurement in a negative mode or at least a first full scan measurement of a first mass filter of the mass spectrometer and a second full scan mode of a second mass filter of the mass spectrometer; wherein a plurality of different full scan MS measurements are selected such that a maximum measurement time in the mass spectrometer is less than 5 minutes; comparing the measurement data for each of the at least two mass axis points with corresponding reference data, wherein comparing the measurement data comprises averaging a plurality of mass spectrometer measurement cycles; A determination is made based on the results of the comparing step whether the mass axis calibration condition is out of specification.

2. The method according to claim 1, wherein the quality axis inspection sample comprises: a mixture of two or more different species spanning the full m / z measurement range of the mass spectrometer, wherein the at least two mass axis points are provided by different species in the mixture; or a single substance capable of fragmenting into two or more fragments of different m / z values, wherein the at least two mass axis points are provided by different fragments; or One or more species selected to form clusters of ions or atoms or molecules that pass through the mass spectrometer at different m / z values ​​to provide the at least two mass axis points.

3. The method of claim 1 or claim 2, further comprising scheduling the processing of the quality axis check sample in an automated scheduling process of the analyzer system.

4. The method of claim 1 or claim 2, wherein the maximum measurement time is less than 2 minutes.

5. The method according to any one of the preceding claims 1 to 4, further comprising: Prior to the step of performing a plurality of full scan mode mass spectrometry measurements, the mass axis inspection sample is processed in a single chromatographic run to separate two or more substances contained in the mass axis inspection sample.

6. The method of any one of claims 3 to 5, wherein scheduling the processing of the mass axis inspection sample in an automated scheduling process comprises minimizing the impact on the throughput of the mass spectrometer or an analyzer including the mass spectrometer.

7. The method according to any one of claims 1 to 5, wherein comparing the measurement data of each of the at least two mass axis points with corresponding reference data comprises: evaluating at least one peak in the measurement data of each of the mass axis points to obtain at least one measurement parameter of each of the at least two mass axis points; comparing the at least one measured parameter of each of the at least two mass axis points with corresponding reference data; as well as A determination is made based on the results of the comparing step whether the mass axis calibration condition is out of specification.

8. The method of claim 7, wherein the at least one measurement parameter comprises one or more of peak position, peak width, peak baseline separation, and peak shape.

9. The method according to any one of claims 1 to 7, further comprising: A mass axis adjustment procedure including separate measurements is scheduled or triggered if the determining step concludes that the mass axis calibration condition is out of specification, or operation of the mass spectrometer is resumed if the mass axis calibration condition is not out of specification.

10. The method according to any one of claims 1 to 9, wherein the maximum measurement time is selected as the duration of a measurement window of a production sample of the mass spectrometer, or is selected as an integer multiple of the duration of a measurement window of a production sample of the mass spectrometer.

11. The method according to any one of the preceding claims 1 to 10, wherein the method of checking the validity of the mass axis calibration of a mass spectrometer comprises at least 50 measurement cycles with a mass interval of at least 2 amu.

12. The method according to any one of the preceding claims 1 to 11, wherein performing mass spectrometry to obtain measurement data for each of the at least two mass axis points comprises using a separate and predefined measurement range for each mass axis point.

13. A method according to claim 1, wherein the results of the multiple full-scan mode MS measurements of the different types are combined to obtain the measurement data for each of the at least two m / z points, and optionally wherein the results of the multiple full-scan mode MS measurements of the different types are averaged to obtain the measurement data for each of the at least two m / z points.

14. The method of any one of the preceding claims 1 to 13, wherein the plurality of full scan mode MS measurements of different types further comprises one or more measurements selected from a list comprising: Measurement in negative mode; Measurement in positive mode; Measurement of a specific mass filter of said mass spectrometer; Measurements at different scanning speeds; Measurements at different scanning resolutions; measurements performed using different ion sources of the analyzer system; and Measurements performed using different detectors of the analyzer system.

15. The method according to any one of the preceding claims 1 to 14, wherein if the step of determining whether the mass axis calibration condition is out of specification concludes that the mass axis calibration condition is within specification but within a predetermined distance from an out of specification threshold, then scheduling preventive maintenance.

16. A computer system configured to perform the steps of any one of the methods according to claims 1 to 15.

17. A computer program product comprising computer executable instructions for performing the method according to any one of claims 1 to 15 when the program is executed on a computer or a computer network.

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