The present disclosure relates to analytical instrumentation, apparatuses and methods. More specific embodiments include mass spectrometry instrumentation, apparatuses, and methods.
Present day analytical instrumentation typically includes an analyte preparation component and a detection component coupled to a processing and control component. The processing and control component typically takes the form of a computer that is configured to control analysis by providing parameters to the analyte preparation and/or the detection components. For example, in the case of mass spectrometry instrumentation, the processing and control component may provide a detection parameter to the detection component, such as a voltage to the electron multiplier and/or engagement of the electron multiplier in the on or off stage. Likewise, the processing and control component may also provide analytical preparation component parameters in the form of ionization energies, ionization times, scan range, and/or waveforms. Typically these parameters are downloaded to these components by the processing and control component and data sets are acquired utilizing these parameters. Upon interpretation of the acquired data sets, the operator of the instrument may feel it is necessary to redefine certain parameters, download these parameters, and acquire additional sets of data.
The present invention provides analytical instruments and analytical processes that provide, in certain embodiments, dynamic modification of analytical component parameters during analysis.
Sample analysis apparatuses are disclosed that can include processing circuitry configured to acquire one data set from an analysis component configured according to one analysis parameter set, and prepare another analysis parameter set using another previously acquired data set.
Sample analysis methods are disclosed that can include acquiring first and second data sets from an analysis component configured according to a first analysis component parameter set provided to the analysis component from a process and control component coupled to the analysis component. Sample analysis methods can also include using the process and control component to process the first data set to prepare a second analysis component parameter set.
Sample analysis instruments are disclosed that can include a processing and control component coupled to an analysis component with the processing and control component comprising processing circuitry coupled to a storage device. The storage device of the instrument can also include analysis component parameter sets associated with data parameter values with individual ones of the analysis component parameter sets being associated with individual ones of the data parameter values. The processing circuitry of the instrument can be configured to process data sets and select an analysis component parameter set from the storage device using a data parameter of the data sets.
Embodiments of the disclosure are described below with reference to the following accompanying drawings.
Embodiments of the analytical apparatuses, instrumentation and methods are described with reference to
Referring first to
Sample 18 can be any known and/or unknown chemical composition. For example, sample 18 can be any chemical composition including both inorganic and organic substances in solid, liquid and/or vapor form. Specific examples of sample 18 suitable for analysis in accordance with the present invention include volatile compounds, such as toluene, or specific examples include highly-complex non-volatile protein based structures, such as bradykinin. In certain aspects, sample 18 can be a mixture containing more than one substance or in other aspects sample 18 can be a substantially pure substance.
Instrument 10 can be any instrument configured with a processing and control component 12 and an analysis component 13. This includes analytical apparatuses used for chemical analysis such gas or liquid chromatographs equipped with detectors such as flame ionization, UV-vis, conductivity, IR, and/or mass spectrometry detectors. Instrument 10 can be configured as described in U.S. patent application Ser. No. 10/542,817 entitled Mass Spectrometer Assemblies, Mass Spectrometry Vacuum Chamber Lid Assemblies, and Mass Spectrometer Operational Methods filed Jul. 13, 2005, the entirety of which is incorporated by reference herein. Instrument 10 can also be configured as described in U.S. patent application Ser. No. 10/554,039 entitled Mass Spectrometry Instruments and Methods, filed Oct. 20, 2005, the entirety of which is incorporated by reference herein. As another example, instrument 10 can be configured as described in International Patent Application Serial No. PCT/US05/20783 entitled Analytical Instruments, Assemblies, and Methods, filed Jun. 13, 2005, the entirety of which is incorporated by reference herein. Instrument 10 can include an analysis component 13 coupled to a processing and control component 12.
Analysis component 13 includes a detection component 16 coupled to the processing and control component. Detection component 16 can include a mass spectrometer, a flame ionization detector, a thermal conductivity detector, a thermal ionic detector, an electron capture detector, or an atomic emission detector. Furthermore, detection component 16 can include an absorbance detector such as an ultraviolet absorbance detector, a fluorescence detector, an electrochemical detector, a refractive index detector, a conductivity detector, a fourier transform infrared spectrometer, a light scattering detector, a photo ionization detector, and/or a diode array detector. Detection component 16 can be an atomic spectroscopy detector, an emission spectroscopy detector, or a nuclear magnetic resonance spectroscopy detector. Exemplary detection components include those described in U.S. patent application Ser. No. 10/537,019 entitled Processes for Designing Mass Separators and Ion Traps, Methods for Producing Mass Separators and Ion Traps, Mass Spectrometers, Ion Traps, and Methods for Analyzing Samples, the entirety of which is incorporated by reference herein. Additional detection components include those described in International Patent Serial No. PCT/US04/29127 entitled Ion Detection Methods, Mass Spectrometry Analysis Methods, and Mass Spectrometry Instrument Circuitry, filed Sep. 3, 2004, the entirety of which is incorporated by reference herein.
Analysis component 13 can also include an analyte preparation component 14, if desired. Analyte preparation component 14 can include chromatography, derivatization, and/or purge and trap components, for example. Exemplary analyte preparation components include those described in U.S. patent application Ser. No. 11/173,263 entitled Spectrometry Instruments, Assemblies and Methods, filed Jun. 30, 2005, the entirety of which is incorporated by reference herein. Analysis component 13 can also be configured as described in U.S. patent application Ser. No. 11/152,395 entitled Instrument Assemblies and Analysis Methods, filed Jun. 13, 2005, as well as described in U.S. Provisional Patent Application Ser. No. 60/681,188 entitled Analytical Instrumentation and Processes, filed May 13, 2005, the entirety of both of which are incorporated by reference herein.
Analysis component 13 can include those analytical components that can be configured according to analysis parameters. According to exemplary embodiments, analysis component 13 can be configured according to analysis parameter sets. For example where analyte preparation component 14 is a gas chromatograph component, the gas chromatograph component is configured according to an analysis parameter set that can include parameters such as injector temperature, oven program, and/or split/splitless relay times. As another example, where analyte preparation component 14 is a liquid chromatograph component, the liquid chromatograph component is configured according to an analysis parameter set that can include parameters such as sample volume and liquid phase composition program.
As another example, analysis component 13 can include detection component 16 that can be configured according to analysis parameter sets. For example and by way of example only, detection component 16 can be a mass spectrometry detector component that includes an ionization component coupled to an ion trap and a detector. The mass spectrometry detector component can be configured according to mass spectrometry analysis component parameter sets that include, for example, ionization time parameters and/or waveform parameters. According to exemplary embodiments, instrument 10 can be configured as described in U.S. patent application Ser. No. 10/570,706 entitled Analysis Device Operational Methods and Analysis Device Programming Methods, filed Mar. 3, 2006, the entirety of which is incorporated by reference herein. Instrument 10 may also be configured as described in U.S. patent application Ser. No. 10/570,707 entitled Mass Spectrometry Methods and Devices, filed Mar. 3, 2006, the entirety of which is incorporated by reference herein. The configuration of analysis component 13 according to analysis parameter sets for the analysis of sample 18 can affect what is acquired in the form of data set 20. For example, in the case of mass spectrometry components, the longer the ionization time, the higher the likelihood data set 20 acquired will be indicative of undesirable effects, such as space charge effects (described below).
Processing and control component 12 can be used to configure analysis component 13 according to analysis parameter sets as well as acquire and/or process data set 20. Data set 20 can include data parameters. For example data parameters of data set 20 acquired using an analysis component configured as a high performance liquid chromatograph coupled to a diode-array detector can include total absorbance, total absorbance at a selected wavelength, and/or absorbance during a selected time or time range. As another example, data parameters of data set 20 acquired using an analysis component configured as mass spectrometer can include total analyte ion abundance and/or total abundance at a specified m/z ratio.
Processing and control component 12 can be a computer and/or mini-computer that is capable of controlling the various parameters of instrument 10. Processing and control component 12 can include processing circuitry 22 and storage device 24. Processing circuitry 22 is configured to acquire analytical component parameters from storage device 24 as well as acquire process data set 20 received from detection component 16, for example. Circuitry 22 is also configured to process data set 20 received from detection component 16 and dynamically modify parameters of analysis component 13. The dynamic modification of the parameters of analysis component 13 can take place while instrument 10 is analyzing sample 18 and/or in between analyses of sample 18 utilizing instrument 10, for example.
Processing circuitry 22 may be implemented as a processor or other structure configured to execute executable instructions including, for example, software and/or firmware instructions. Processing circuitry 22 may additionally include hardware logic, PGA, FPGA, ASIC, and/or other structures. In exemplary embodiments, data set 20 may be output from instrument 10 via FPGA processing circuitry 22. In another embodiment, data set 20 may be directly output from a bus of processing circuitry 22 where an appropriate bus feed is provided. Processing circuitry 22 may include an analog to digital converter (ADC) to retrieve, record, and/or convert data set 20 during analog processing utilizing processing circuitry 22. Processing circuitry 22 may also amplify analog signals received from detection component 16 before processing data set 20.
Storage device 24 is coupled to processing circuitry 22 and is configured to store electronic data, programming, such as executable instructions (e.g., software and/or firmware), data, or other digital information that may include processor usable media. Processor usable media includes any article of manufacture which can contain, store, or maintain programming data or digital information for use by, or in connection with, an instruction execution system including processing circuitry in the exemplary embodiment.
Exemplary processor usable media may include any one of physical media such as electronic, magnetic, optical, electromagnetic, infrared or semiconductor media. Some more specific examples of processor usable media include, but are not limited to, a portable magnetic computer diskette, such as a floppy diskette, zip disk, hard drive, random access memory, read only memory, flash memory, cache memory, and/or other configurations capable of storing programming, data, or other digital information.
Processing and control component 12, including processing circuitry 22 in combination with storage device 24, may be utilized to dynamically modify parameters of analysis component 13 by processing data set 20 in the context of the analysis component parameters used to generate data set 20. For example, data set 20 can include parameters of the data set, such as total analyte ion abundance in the case of a mass spectrometry instrument data set. The total abundance can be processed in the context of the analysis component parameters used to generate the data set parameter, such as ionization time parameter of an ion source component. Upon processing data set 20 in the context of the analysis component parameters used to generate data set 20, the component parameters may be modified, analysis component 13 can be reconfigured with the modified parameters, and a subsequent analysis of sample 18 performed using instrument 10 as reconfigured. This dynamic analysis may be utilized continuously or intermittently as the user of instrument 10 desires.
Acquisition and generation of data according to the present invention can be facilitated with processing and control component 12. Processing and control component 12 can be a computer or mini-computer that is capable of controlling the various elements of instrument 10. This control includes the specific application of RF and DC voltages as described herein and may further include determining, storing and ultimately displaying mass spectra. Processing and control component 12 can contain data acquisition and searching software. In one aspect such data acquisition and searching software can be configured to perform data acquisition and searching that includes the programmed acquisition of the total analyte count described above. In another aspect, data acquisition and searching parameters can include methods for correlating the amount of analytes generated to predetermined programs for acquiring data.
According to an exemplary embodiment reference is made to
Inlet system component 26 can be configured to introduce an amount of sample 18 into instrument 10. Inlet system component 26 may be configured to prepare sample 18 for ionization. Types of inlet system components can include batch inlets, direct probe inlets, chromatographic inlets, and permeable or capillary membrane inlets. Inlet system component 26 may be configured to prepare sample 18 for analysis in the gas, liquid and/or solid phase. In some aspects, inlet system component 26 may be combined with ion source component 28.
Ion source component 28 can be configured to receive sample 18 and convert components of sample 18 into analyte ions. This conversion can include the bombardment of components of sample 18 with electrons, ions, molecules, and/or photons. This conversion can also be performed by thermal or electrical energy. In one aspect, ion source component 28 can provide a predetermined amount of energy to sample 18. Providing this predetermined energy amount to sample 18 provides a sample containing at least one ionized molecule and/or molecules, and can also provide the formation of other molecules and ions, as demonstrated by equation 1 below:
M+
M
+·
+E′→M
+
+F
+
+N+E″ (1)
wherein M represents the neutral analyte molecules, E represents the energy provided to M; M+· represents an internally excited ion; E′ represents any E not deposited into M+· as internal or kinetic energy; M+, F+ and N represent charged analyte ions, charged dissociation products, and neutral dissociation products, respectively; and E″ represents any E not remaining in M+, F+ or N as internal or kinetic energy. A variable energy ion source component 28 may impact the amount of dissociation of sample into these other, molecules (F+ and N), for example.
Ion source 28 may utilize electron ionization (EI, typically suitable for the gas phase ionization), photo ionization (PI), chemical ionization, collisionally activated disassociation and/or electrospray ionization (ESI). For example in PI, the photon energy can be varied to vary the internal energy of the sample. Also, when utilizing ESI, the sample can be energized under atmospheric pressure and potentials applied when transporting ions from atmospheric pressure into the vacuum of the mass spectrometer can be varied to cause varying degrees of dissociation (often referred to as “nozzle/skimmer” or “cone voltage” dissociation). Referring to
Referring again to
An exemplary depiction of “gating” is shown in
Mass analyzer component 32 can include magnetic sectors, electrostatic sectors, and/or quadrupole filter sectors. More particularly, mass analyzer component 32 can include one or more of triple quadrupoles, quadrupole ion traps, cylindrical ion traps, linear ion traps, rectilinear ion traps, ion cyclotron resonance and quadrupole ion trap/time-of-flight mass spectrometers. Quadrupole ion traps or “Paul traps” can refer to an ion trap having a toroidal ring electrode and two end caps. The toroidal ring electrode may have a hyperbolic shape in one cross section. The two end caps may also have a hyperbolic shape in one cross section. Cylindrical ion traps (CIT) have been considered a variation on the quadrupole ion trap where the ring electrode and end caps may have flat surfaces in one cross section. Linear ion traps can consist of sets of parallel rods, the rods being either round, hyperbolic, and/or flat in one cross section. Referring to
Referring next to
As depicted in
Referring to
According to exemplary embodiments, during analysis component parameter set 3, the trapping RF of mass analyzer component 32 is turned on, focusing DC amplitude is turned off, and ion transport gate component 30 is open. Mass analyzer component 32 is filled for a predefined time or a time calculated from the total analyte ion abundance. As depicted in
According to exemplary implementations, mass analyzer components 32, such as linear ion traps may have an RF voltage applied to the parallel rod electrodes during the analyses such as those with analysis component 13 configured according to the analysis component parameters of set 1. This can provide focusing of the analyte beam to the detector. This focusing RF may be at a different amplitude and/or frequency than the trapping RF used to store ions for manipulation as described in sets 3-5 in
Referring to
Referring to
At S20, data set #1 is acquired using an instrument configured with analysis component parameter(s) set #1. According to exemplary embodiments, analysis component 13 can be configured according to a first analysis component parameter set as dictated by processing and control component 12. Analysis component parameter set #1 can be used to configure analysis component 13 (
Data set #1 can include the data acquired utilizing an instrument configured with analysis component parameter set #1. In keeping with the theme of mass spectrometry as above, data set #1 can be the data set acquired using a mass spectrometry instrument. For example, and by way of example only, the data set can include data set parameters such as total ion current, selective ions detected, selected mass range detected, and/or mass spectra detected.
Hereafter the process proceeds to S22 where the data set acquired in S20 is sorted by a predefined data set parameter and/or parameters to isolate predefined data parameter(s), such as total analyte ion abundance.
The process then can proceed to S24 where a determination is made as to whether or not the acquired data parameter sorted in S22 is greater than a predefined minimum. According to exemplary embodiments, the predefined minimum may be associated with the first analysis component parameter set within storage device 24, for example. The acquired data parameter of the first data set can be compared with the defined threshold amount to selectively dictate the first or second analysis parameter set to the analysis component. For example, if a total amount of a certain ion is the acquired data parameter, then a determination would be made if that amount of ion is greater than the predefined minimum ion amount. Where the acquired data parameter is greater than the predefined minimum, the process proceeds to S26 and analysis begins with instrument 10 (
In the case the acquired data parameter is less than the minimum, the process proceeds to S28 where data set #2 is acquired using analysis component parameter set #2, the second analysis component parameter set. In an exemplary embodiment, and in keeping with the theme of mass spectrometry, analysis component parameter set #2 can include a mass spectrometry range other than the mass spectrometry range defined using analysis component parameter set #1 above, or parameter set #2 can include a longer open gate time to facilitate the acquisition of more analyte ions by mass analyzer 32 (
The process proceeds to S30 where the acquired data set #2 is sorted by one or more predefined data set parameters that may be equivalent to the predefined data set parameters used to sort data set #1 above. For example, the data set can be sorted by data set parameters such as abundance of an ion and/or TIC.
Proceeding to S32, a determination is made as to whether or not the acquired data parameter sorted in S30 is greater than a predefined minimum. This predefined minimum may be associated with the second analysis component parameter set in storage device 24, for example. For example, as described above, whether or not the ion abundance and/or TIC acquired using the instrument configured with analysis component parameter set #2 is greater than a predefined ion abundance or TIC minimum. In the case the acquired data parameter is greater than the minimum, the process proceeds to S34 which dictates that analysis should begin starting with analysis component parameter set #2. Where it is the case that the predefined data parameter is less than the minimum the process can return to S20.
As but one example utilizing the process described in
Utilizing this process, for example, and in keeping with the mass spectrometry theme but not limited thereby, instrument 10 (
With reference to S28 of
In accordance with an exemplary embodiment and referring to
Analytical methods can include acquiring first and second data sets from an analysis component configured according to a first analysis component parameter set provided to the analysis component from a process and control component coupled to the analysis component. The methods can also include processing the first data set to prepare a second analysis component parameter set using the process and control component.
According to exemplary embodiments, the processing of the first data set can be performed during the acquiring of the second data set. The analysis component can also be configured according to the second analysis component set. Methods can also include acquiring a third data set from the analysis component configured according to the second analysis component set, and processing the second data set to prepare a third analysis component parameter set using the process and control component. The processing of the second data set can be performed during the acquiring of the third data set, for example.
For example and referring first to S40, a data set #1 can be acquired using an analysis instrument configured with analysis component parameter set #1. According to exemplary embodiments, analysis component 13 can be configured to include the ion source component, the transport gate component and the mass analyzer component. These components can be configured to provide analyte ions to the detection component according to one analysis component parameter set and reconfigured according to another analysis component parameter set, for example. The analysis component parameter sets can include one or more of ion gate position parameters, trapping RF amplitude parameters, focusing DC amplitude parameters, and detector power parameters described in detail previously. Parameter set #1 can be predefined and/or can be dictated using the process described above in
The process proceeds to S42 where data set #2 is acquired using analysis component parameter set #2 and simultaneously, for example, analysis component parameter set #3 is prepared by processing data set #1 using processing and control component 12. The process proceeds to S44 where data set #3 is acquired using analysis component parameter set #3 prepared in S42 and analysis component parameter set #4 is prepared based on data set #2 acquired in S42. The process can continue in this acquisition and parameter preparation mode as continued in S46 where data set N is acquired using analysis component parameter set N, and analysis component parameter set N+1 is prepared from data set N−X, with X being 2, 3, 4, etc.
The process can then proceed to S48 where, in an exemplary embodiment, but not necessarily, the data sets and/or individual data set parameters acquired during the process can be scaled consistent with the prepared analysis component parameter sets. According to exemplary embodiments, processing circuitry 22 of processing and control component 12 can be further configured to scale the data sets using the analysis parameter sets used to acquire the data sets. For example, the analysis parameter sets can include a gating parameter and the data sets are scaled using the gating parameter, such as the length of time the gate is open.
Referring to S42, S44, and S46 of
The process then continues to S54 where a determination is made as to whether or not the data set parameter exceeds a predefined upper threshold. For example, another analysis parameter set is prepared by acquiring a data set parameter of another data set and comparing the other data set parameter to a threshold amount. According to exemplary embodiments, the data set parameter is the total analyte ion abundance of the data set. The threshold amount can be an upper limit amount of the abundance, for example. The comparing can include determining an excess of the upper limit amount and storing the excess.
The apparatus can be configured with the threshold amount being a lower limit amount and the comparing can include determining a deficiency of the lower limit amount and storing the deficiency. For example, if the data set parameter does exceed the upper threshold then an incremental count of the exceeding amount is made at S56 and then the process continues to S58 where a determination is made as to whether or not the data set parameter exceeds a predefined lower threshold. Where the lower threshold is exceeded an incremental count of the exceeding data set parameters of that lower threshold is made and then the process continues on to S62 where a determination is made to whether the data set parameter has exceeded a predefined maximum value. According to exemplary implementations, the other analysis parameter set is further prepared by comparing the stored excess to this excess maximum. Where the predefined maximum value has been exceeded, that value is noted in S64, the process continues to S66, and a summation of the upper counts, lower counts, and the determination of the number of times the maximum value has been exceed is recorded.
Upon summation, the process can continue to S68 where a determination is made as to whether or not more data is required. If more data is required, the process returns to S50; if not, the process can continue onto the process outlined in
According to exemplary embodiments the apparatus can be configured to compare the excess count of the data parameter with data set parameter limit associated with the analysis component parameters used to acquire the data set. For example, referring to
When the upper count has not exceeded the upper count limit, the process can continue to S74 where a determination is made as to whether the recorded maximum value(s) have exceeded the maximum value limit. If the limit has been exceeded, the process can continue onto S72 as described above. If not, the process can continue onto S76 and a determination is made as to whether the total of the maximum value exceeding times and the upper count limit exceeds a predefined data set parameter limit and if so, the process proceeds onto S72 as described above.
From S72, after modification of the analysis component parameter set, a determination is made as to whether the modified analysis component parameter set includes a predefined analysis component parameter that is greater than a predefined minimum in S78. Where the modified parameter is greater than the predefined minimum, the process proceeds to S82 where the modified analysis component parameter set is stored. For example, where the data set parameter is the total analyte ion abundance of the data set and it is determined that the excess is greater than the upper limit, the analysis component parameter set used to acquire the data set can be modified to include a decreased ionization time parameter. This modified analysis component parameter set may then be used to reconfigure analysis component 13 as described.
Where the modified parameter is less than the predefined minimum, the modified parameter is set at a predefined minimum and the modified parameter set is stored in device 24 (
According to exemplary embodiments, the modified analysis parameter set can be prepared by comparing the stored deficiency to a deficiency maximum. For example, referring to S76 of
Referring to S84 of the process shown in
Referring to
As is indicated using the variable N in
Referring to
In keeping with the theme of mass spectrometry but not limited thereby, recall the gating described above with reference to instrument 10 and
In an exemplary embodiment, the ionization time parameter for a given parameter set can be varied, for example, by modifying an ionization parameter based on previously acquired data and providing these modified parameters to the components of the instrument during subsequent analyses. As described above, mass analyzer components can have parameters provided to them that include such parameter(s) as voltage waveforms that manipulate the analyte ions in the mass analyzer component such as an ion trap. These voltage waveform parameters in combination with other analytical parameters such as ionization time parameters can be dynamically modified and dictated to the analysis components with the processing and control components via relays that control the timing of various events during analysis in accordance with the processes described herein.
For example, an instrument can produce an RF waveform parameter and apply that parameter to a mass analyzer component. In so doing, the mass analyzer component can be configured to store analyte ions of a predetermined mass to charge ratio and analyze analyte ions by providing specific analyte ions to detection components at predetermined frequencies by executing the digitized waveform information at a fixed rate. The rate can include rates such as 20 million samples per second (MSamples/sec). In an exemplary embodiment, analytical parameters can be provided to an instrument with the analytical parameters including an ionization time parameter having a fixed period of ionization as the first event of the mass analysis parameter. The ionization time parameter can be set to any value from zero to the full period specified in the mass analysis parameter, for example, by specifying the start offset of the mass analysis scan parameter to something other than the first data point of the scan.
For example, if a scan parameter is downloaded to the mass analysis component, such as an ionization parameter of 10 milliseconds, this can represent 200,000 data points stored in memory to represent the RF waveform of the mass analysis component during that 10 millisecond period. Where an ionization time of 5 milliseconds is provided to the instrument, the instrument can begin clocking out the data set acquired from the instrument not with the first point of the ionization time, but rather at data point number about 100,000 later in the mass analysis scan parameter. In exemplary embodiments, the relay that allows for providing the ionization time can be turned on during this 5 millisecond time period resulting in a 5 millisecond ionization time. By specifying where to begin clocking out the data, the ionization time can be set to any value required without the need to recalculate the waveform parameter downloaded to the mass analyzer component.
In particular embodiments, and with reference to
In exemplary embodiments and as described above with reference to
Referring to
At S208 a determination is made as to whether or not the total ion current has exceeded the lower threshold. Where the lower threshold has been exceeded, an incremental count of the data points below the lower threshold is made at S210 and the process proceeds to S212.
At S212 a determination is made as to whether or not the total ion current is greater than the maximum predefined by the user. Upon a determination that a maximum is exceeded, the total number of times that the maximum is exceeded is accounted for in S214. The process then proceeds by totaling the incremental upper limit, the incremental lower count and the maximum values in S216.
After S216 the process proceeds to S218 where a determination is made as to whether or not more data points need to be acquired. If more data points do need to be acquired, the process reverts to S200 and more data points are acquired. If not, the process proceeds to S220 in
Referring to S220 where the upper count is less than or equal to the limit, the process proceeds to S228 where a determination is made as to whether the maximum values recorded are greater than the limit. Where the maximum values are greater than the limit, the process proceeds to S222 as described above. Where the maximum value is less than the limit, the process proceeds to S230 where the total value is compared to the total value limit. Where a determination is made that the total is greater than the limit, the process proceeds to S222 as described above. Where it is less than the limit, the process proceeds to S232 for determination of whether the lower count is less than the limit. Where the lower count is less than the limit, the process proceeds to S234 where the ionization time parameter of the parameter set used to acquire the data set is modified to increase the ionization time.
The process then proceeds to S236 where a determination is made as to whether the modified ionization time parameter is greater than the predefined maximum. Where it is greater than the maximum, the process proceeds to S238 where the maximum ionization time parameter is set and the modified parameter is stored. Where it is less than the maximum, the modified set is stored in S240.
Referring again to S232, where it is the case that the lower count limit is greater than the limit, the process proceeds to S242 where the same parameter used to acquire the data set having the total ion current parameter is stored for use in subsequent analyses.
In an exemplary embodiment, after modification of these parameters, the data set parameters acquired using modified parameters can be scaled as described above with reference to
Referring to
This application claims priority to U.S. Provisional Patent Application No. 60/675,340 filed Apr. 25, 2005, entitled “Analytical Instrumentation and Analytical Processes” the entirety of which is incorporated by reference herein.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US2006/015948 | 4/25/2006 | WO | 00 | 7/20/2009 |
Number | Date | Country | |
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60675340 | Apr 2005 | US |