Patent Application
20220178890
The present disclosure is directed generally to the performance of maintenance evaluations on a gas chromatograph (GC) or a gas chromatograph-mass spectrometer (GC-MS). More particularly, the present invention relates to systems and methods enabling the automated performance of GC/GC-MS health and diagnostics evaluations and reporting, including systems and methods for generating maintenance recommendation reports based on the health and diagnostics evaluations.
Analytical or scientific instrument systems such as gas chromatographs or gas chromatograph-mass spectrometers may be used in connection with sample analyses. In connection with such instrument systems, scheduled diagnostic and maintenance activities may be performed according to a predetermined schedule. For instance, regularly scheduled instrument diagnostics testing may be required, followed by any necessary maintenance of the instrument system as determined by the diagnostics testing to proactively clean, replace, or perform other activities on the various parts or components of the instrument system to correct malfunctions or otherwise to ensure proper function going forward.
Health and diagnostic testing procedures are commonly performed manually to ensure that the instrument system's performance is acceptable before or after completion of maintenance. Such manual testing may have drawbacks. Typically, a highly skilled and qualified technician is required to perform such maintenance and testing. Additionally, the manual testing may be inconsistently performed across serviced instruments thereby leading to inconsistent results regarding instrument performance after completion of the scheduled maintenance. Furthermore, performing the testing manually as well as gathering and analyzing test results manually may be time consuming, cumbersome, and error prone.
The disclosure is directed to a novel method and apparatus which provides performance of maintenance evaluations on GC/GC-MS instrument systems. More particularly, the present invention relates to systems and methods enabling the automated performance of GC/GC-MS health and diagnostics evaluations and reporting, including systems and methods for generating maintenance recommendation reports based on the health and diagnostics evaluations.
In accordance with the concepts described herein, one scientific instrument for providing performance of maintenance evaluations on GC/GC-MS instrument systems is described. The instrument can include a material analysis chamber, an injector, a data processor, and a controller. The material analysis chamber can include an input port, and the injector can be configured to insert one material sample from a plurality of material samples into the material analysis chamber via the input port. The material analysis chamber can be configured to perform a scientific analysis of the inserted material sample, where the plurality of material samples can include at least one diagnostic material sample. In some versions, the data processor can include a memory storing correlation data for comparing a first set of results of a first scientific analysis to expected results associated with the at least one diagnostic material sample to form a first set of compared results. The data processor can be further configured to selectively generate an output report of the first set of compared results.
In some versions, a controller can be operatively coupled with the material analysis chamber, the injector, and the data processor. The controller can be configured to receive a first command via a user input feature, and upon receiving the first command at the user input feature, autonomously direct the injector to inject the at least one diagnostic material sample into the material analysis chamber. The controller can further initiate the scientific analysis to formulate the first set of results, direct the data processor to analyze the first set of results and to generate the first set of compared results, and direct the data processor to generate a first output report illustrating the first set of compared results.
As such, the systems and methods disclosed can provide improved automated diagnostics and reporting for gas chromatograph systems, gas chromatography-mass spectrometry systems, or for other systems of chromatography.
The foregoing has outlined rather broadly the features and technical advantages of the present disclosure in order that the detailed description that follows may be better understood. Additional features and advantages will be described hereinafter which form the subject of the claims. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the disclosure as set forth in the appended claims. The novel features which are believed to be characteristic of the disclosed systems and methods, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present disclosure.
For a more complete understanding of the present disclosure, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
In the description herein, it is understood that a word appearing in the singular encompasses its plural counterpart, and a word appearing in the plural encompasses its singular counterpart, unless implicitly or explicitly understood or stated otherwise. Furthermore, it is understood that for any given component or embodiment described herein, any of the possible candidates or alternatives listed for that component may generally be used individually or in combination with one another, unless implicitly or explicitly understood or stated otherwise. Moreover, it is to be appreciated that the figures, as shown herein, are not necessarily drawn to scale, wherein some of the elements may be drawn merely for clarity of the disclosure. Also, reference numerals may be repeated among the various figures to show corresponding or analogous elements. Additionally, it will be understood that any list of such candidates or alternatives is merely illustrative, not limiting, unless implicitly or explicitly understood or stated otherwise. In addition, unless otherwise indicated, numbers expressing quantities of ingredients, constituents, reaction conditions and so forth used in the specification and claims are to be understood as being modified by the term “about.”
Accordingly, unless indicated to the contrary, the numerical parameters set forth in the specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the subject matter presented herein. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the subject matter presented herein are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical values, however, inherently contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.
Numerous types of scientific instruments exist for the compositional analysis of fluids, including liquids and gasses. Although the invention will be described with regard to the compositional analysis of fluids in GC/GC-MS applications, it can be extended to apply to the other related applications. For example, liquid chromatography (LC) and liquid chromatography-mass spectrometer (LC-MS) applications.
GC-MS is a technique to determine the quantity and identity of components in an analyte. The analyte is injected into a gas chromatograph which separates the mixture into its individual components, and the output from the gas chromatograph may be fed into a mass spectrometer which determines the molecular formula of each component (each referred to herein as a “scientific analysis”). The mass spectra of each component can often be compared against a known library of mass spectra of known compounds. GC-MS is frequently used in analysis of environmental contaminates, food safety, forensics, toxicology, and metabolomics.
In typical procedures for evaluating, diagnosing, or troubleshooting the health of GC/GC-MS instrument systems, a user manually inputs a standardized diagnostic material sample into the instrument and reviews the results. Thereafter, the user determines what maintenance activities are necessary, if any. End-to-end automation of a full-system evaluation of a GC/GC-MS instrument, along with the automatic generation of reports and recommendations for maintenance, is needed to increase the operative efficiency of the lab and reduce the specialized skills and costs associated with the routine, manual evaluations. If the injection, processing, post-processing analysis, and reporting of the results are seamlessly automated by the instrument, the instrument would only require a single input mechanism, such as a push-button accessible by a user or a pre-scheduled or other software-based triggering condition, to initiate the testing and generate recommendations for maintenance on the instrument.
To enable the end-to-end evaluations to run autonomously, individual compounds in one or more diagnostic material samples are pre-loaded into the instrument and formulated to test different aspects of chromatography, such as contamination in the inlet or guard column, active sites, degradation of stationary phase, or other aspects of the instrument which may typically require maintenance. For example, when a GC instrument is used to repeatedly test analytical samples, various components along the sample pathway can degrade over time, which can gradually impact performance of the instrument. Many factors can lead to this damage, such as thermal degradation, buildup of non-volatile compounds, oxidation from leaks, physical or chemical damage to surfaces, septum coring, etc. The injected sample potentially touches multiple surfaces from injection, volatilization, separation, and eventual detection. Ultimately, this damage along the flow path leads to active sites, which interact with the injected compounds to be analyzed. This unwanted interaction can manifest in various ways, such as peak tailing, peak fronting, peak broadening, compound reactions, and analyte suppression.
The typical strategy for performing an analysis using a diagnostic test mix is to have a variety of compound types formulated to evaluate specific aspects of the instrument system. The various properties of these compound types allow for the evaluations to determine where specific instrument component wear (health monitoring) is occurring and to recommend specific maintenance steps needed to bring the instrument system back to a healthier status. For example, the below is a listing of potential test mix components and how they can be utilized to evaluate system health.
Particularly, acids and bases generally identify the presence of acid and base activation sites, which can specifically bind compounds based on alkalinity. Hydroxyl compounds (alcohols) may be useful for identifying active sites due to their polarity and potential for hydrogen bonding, which can make them useful for identifying oxidative damage or exposed glass, such as from broken column pieces. Alcohols may be particularly sensitive to adsorption sites when compared to most other polar compounds. Fatty acid methyl ester compounds (FAMEs) can be useful for quantitating the film thickness of a column. However, there may in some instances be limited application for this for assessing column health. Hydrocarbons are non-polar compounds and can be generally immune to most active sites. In this application, they can be useful as an internal standard as their intensity can be measured relative to the other peaks in the mix.
In general, the traditional test mix of the components listed in Table 1 may be a useful starting point for validating chromatography health, though the listed components merely represent one example and diagnostic test mix samples are in no way limited to the compounds of Table 1. For instance, inlet reactivity can be identified with endrin or 4,4′-DDT. As another example, DFTPP (Decafluorotriphenylphosphine) may be a useful compound for evaluating MS performance if an MS is coupled to the GC as a detector. Different test mixes may also be tailored to a specific application. System performance check compounds are useful for evaluating performance relative to specific analysis methodology. An alternative approach may be to replicate the manufacturer's test data for each column.
Referring now to the drawings,
GC-MS instrument system 100 includes a gas chromatograph 102 and a mass spectrometer 104. Gas chromatograph 102 further includes an injector port 106 positioned adjacent to and fluidly coupled to an oven 108 via a tube 110. Particularly, tube 110 fluidly couples with a gas chromatograph column 112. To perform a scientific analysis within the column 112, a material sample 114, typically in the form of a liquid, is injected into injector port 106 along with a carrier gas, or mobile phase, 116. Thereafter, column 112 of oven 108 separates material sample 114 into its individual components, which then travels through the exit port 118, typically in the form of a gas. As the gas exits oven 108 at exit port 118, it may optionally be input into mass spectrometer 104. Mass spectrometer 104 may be, for example, a quadrupole-based instrument system, ion trap, time-of-flight, or any other known and commonly used instrument system for mass spectrometry. A typical quadrupole-based instrument system includes an ionization chamber 120, a source slit 126, a set of quadrupole rods 128, an exit slit 130, and a detector 122. Ion optics, ion guides, and other mass-resolving devices may exist between the ionization chamber 120 and the detector 130. In its most basic form, the gas enters ionization chamber 120, it is ionized and the particles accelerated through source slit 126, through quadrupole rods 128, and through exit slit 130 before reaching detector 122. Detector 122 then detects the particles as they are received, before analysis is done via a data processor 134 using known data stored in memory 148 to determine the molecular formula of each component.
While data processor 134 is illustrated as associated with detector 122 of mass spectrometer 104, it should be understood that data processor 134 may also be associated with a detector (not shown) at exit port 118 of gas chromatograph for separately analyzing the components of the materials traveling therethrough. Examples of typical gas chromatograph detectors are flame ionization detectors, thermal conductivity detectors, or the like. Further, while memory 148 is illustrated as being associated with data processor 134 for storing known data, memory 148 may be included in controller 136 alternative to or in addition to being located in data processor 134, and memory 148 may be configured to store data sets generated by GC/GC-MS runs and evaluations for later use to develop and report data trends. For example, each time an evaluation is performed and the resulting data is generated, that data set may be stored for comparison against data collected during a second or later evaluation.
To operate each of the components and the procedures described above, GC-MS instrument system 100 may further include a controller 136 comprised of specialized computer processing equipment having software and hardware configured for operating GC-MS instrument system 100. As such, controller 136 may be operatively coupled (as shown by the dashed lines), such as using electrical and/or data cables, with each and every component of system 100, including but not limited to injector port 106 (including injectors 208 and 304 of
To affect end-to-end automation of a full-system evaluation of a GC/GC-MS instrument, injection of the material sample is only one portion of the process which may be automated. With reference to
One potential limitation is that traditional vials 214 and septa 210, once punctured, can sometimes allow for the material sample to gradually evaporate, thereby changing the concentration of the material contained within them over time. As such, in some versions, the autosampler may be configured to contain an improved vial 216 designed to hold the diagnostic material sample 204, where instead of a septum 210, a specialized lid 212 opens for the sample extraction, and then reseals when not in use. As such, the improved vial 216 would therefore be capable of preserving a larger volume of diagnostic material samples 204 and for a much longer period of time than standard or traditional vials 214.
With reference to
With reference to
Thereafter, at step 406, a method is optimized to analyze the diagnostic material sample. This method may be stored locally or in the cloud by the instrument and it may be automatically modified by the controller based on various configuration parameters, such as the type of column that is currently installed (e.g., depending on the length, inner diameter, outer diameter, stationary phase thickness, etc.), the type of GC or MS instrument that is configured (e.g., a single quadrupole, triple quadrupole, Orbitrap, etc.), and the GC inlet that is being used. Based on the column phase, a plurality of different diagnostic material samples may be readily available for retrieval by the instrument system to properly evaluate the system in its current configuration. As such, the controller is configured to initiate and direct an evaluation of the health of the instrument system in a controlled fashion, rather than to evaluate a specific application using the instrument system. It should be understood that, in some versions, configuration parameters may be stored nearby or on a surface of the container holding the diagnostic material, and which the configuration parameters are readable (e.g., using RFID or other similar techniques) by the instrument prior to initiation of the scientific analysis.
In addition to utilizing the diagnostic material sample for diagnosing the GC instrument health, the controller may also activate the calibration gas at the end of the GC analysis run for assessing additional aspects of MS health. For instance, with the calibration gas, SIM/SRM isolation and efficiency could be quickly determined as well. As such, one embodiment of the methods described herein would be to strictly evaluate GC and chromatography health, while a second embodiment could also encompass MS health and tuning.
At step 408, post processing software (which may be configured to operate on the embedded instrument firmware, such as within the data processor 134 or the controller 136) would analyze the raw data sets as detected by the GC column 112 or the MS detector 124. For instance, with regard to the GC column 112, post-processing and analysis of the data set could review the mass traces that are representative of the test compounds. Various chromatographic information can be gathered from this such as, but not limited to, the retention time of compounds, peak tailing, peak shape, peak areas, column bleed level changes during the oven ramp, other chromatographic characteristics, ion ratios (MS), or mass accuracy (MS). The post processing software may be configured to analyze and compare the raw data sets with one or more data sets stored within the memory, such as an ideal data set, including an output data set for the analyzed diagnostic material that would be expected under normal operating conditions by a healthy instrument. In other versions, the software may be configured to analyze and compare the raw data sets with a data set stored from a prior scientific analysis of the same or a similar diagnostic material, or from an online storage database.
With regard to the MS detector 124, post-processing and analysis of the data set using the calibration gas portion could provide several other useful metrics for evaluating MS health. This type of evaluation can be performed after the retention time of the last compound and during the oven cool down period, and can provide data to analyze ion intensities, ion ratios, mass accuracy, air or water levels (with calibration gas on or off), leak check percentage, SIM/SRM isolation efficiency, collision energy evaluations, rapid tuning to see if other ion optic values may be more suitable (continuous tuning), or other useful data.
At step 410, after the data are analyzed and optionally compared to previous trends, a report can be generated. In some versions, the report may be displayed to the user via the display screen 144 while in other versions, the report may be stored locally or in a cloud-based server for TCP/IP based for remote viewing, or transmitted to a remote user through the internet via hard wiring or transmitter 146. The output report may be configured to summarize the results and highlight or recommend which, if any, maintenance actions might be required (e.g., directing a user to trim the column, replace the liner, recalibrate the instrument, etc.). If tuning or recalibration is required, this can be triggered automatically by the instrument system to be completed. In other alternative versions, if the GC/GC-MS instrument system is connected in an IoT (Internet of Things) framework, a push notification can be generated to mobile devices and to the data system.
It is to be understood that features described with regard to the various embodiments herein may be mixed and matched in any combination without departing from the spirit and scope of the disclosure. Although different selected embodiments have been illustrated and described in detail, it is to be appreciated that they are exemplary, and that a variety of substitutions and alterations are possible without departing from the spirit and scope of the present disclosure.
