Polymer analysis device and method
Patent Information
- Application Number
- JP2022156709
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2022-09-29
- Publication Date
- 2025-03-26
- Estimated Expiration
- 2042-09-29
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Figure 0007651536000001 
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Abstract
Description
[Technical field]
[0001] The present invention relates to an apparatus and method for analyzing polymers, and in particular to a technique for analyzing the mass of terminal groups and the like. [Background technology]
[0002] A polymer is an aggregate of multiple molecules (hereinafter referred to as "polymer molecules") with various degrees of polymerization. Each polymer molecule consists of a main chain portion and other portions (hereinafter referred to as "non-main chain portions").
[0003] The main chain portion has a structure in which multiple repeating units are linked together. The number of repeating units that make up the main chain portion is the degree of polymerization. The non-main chain portion includes two end groups that are linked to both ends of the main chain portion. Hereinafter, the two end groups may be simply referred to as "end groups". The non-main chain portion may include one or more additional ions. For example, when a polymer is cationized using a cationizing agent, one or more additional ions are attached to the main chain portion of each polymer molecule. Hereinafter, the one or more additional ions included in the non-main chain portion may be simply referred to as "additional ions".
[0004] The mass spectrum obtained by mass spectrometry of a polymer contains multiple peaks corresponding to multiple polymer molecules with different degrees of polymerization. These multiple polymer molecules are also called a polymer series. In the mass spectrum of a polymer, the peak interval corresponds to the mass of the repeating unit, i.e., the mass of the monomer molecule. It is generally easy to predict the presence or absence of adduct ions and the mass of the adduct ions when they are generated. In contrast, it is very difficult to directly estimate the mass of the end group from the mass spectrum of a polymer.
[0005] Kendrick Mass Defect analysis (KMD analysis) is known as a polymer analysis method (see, for example, Patent Document 1). KMD analysis uses the ratio of the exact mass of a repeating unit to the integer mass of the repeating unit to obtain Kendrick mass defect (KMD) as a feature that does not depend on the mass of the repeating unit (which may also be called the mass of the main chain portion) and depends on the mass of the non-main chain portion.
[0006] In general, the end groups contained in a polymer determine the chemical properties of the polymer. Therefore, it is important to identify the composition of the end groups in polymer analysis. However, conventional KMD analysis cannot uniquely identify the mass of the non-main chain part including the end groups.
[0007] Although Non-Patent Document 1 describes a technique for estimating the elemental composition of the end groups in a polymer, the document does not describe the use of two polymers that have a special relationship. [Prior art documents] [Patent documents]
[0008] [Patent Document 1] JP 2020-008314 A [Non-patent literature]
[0009] [Non-Patent Document 1] "Estimation of elemental composition of polymer end groups using accurate mass" (Applications note MS: MSTips No. 357), 2021, JEOL Ltd., [Retrieved September 27, 2022], Internet<URL:https: / / www.jeol.co.jp / applications / detail / 2160.html> Summary of the Invention [Problem to be solved by the invention]
[0010] An object of the present invention is to identify the mass of a non-main chain portion in a polymer. Alternatively, an object of the present invention is to provide information for identifying the mass of a non-main chain portion in a polymer. [Means for solving the problem]
[0011] The polymer analysis apparatus according to the present invention includes a first mass spectrum of a first polymer, and having a main chain portion different from the main chain portion of the first polymer; a processor for processing a second mass spectrum of a second polymer having the same non-main-chain portion as the non-main-chain portion of the first polymer, the processor calculating at least one mass candidate for the non-main-chain portion based on a first polymer molecular mass and a first repeating unit mass identified from the first mass spectrum, applying a Kendrick Mass Defect (KMD) analysis to the at least one mass candidate using the first repeating unit mass, thereby generating a first KMD analysis result, and calculating a second repeating unit mass identified from the second mass spectrum for the second mass spectrum. a second repeating unit mass different from the first repeating unit mass thereby generating a second KMD analysis result; and generating an image for identifying the mass of the non-main-chain portion or determining the mass of the non-main-chain portion based on the first KMD analysis result and the second KMD analysis result.
[0012] The polymer analysis method according to the present invention includes: determining a first polymer molecular mass and a first repeating unit mass identified from a first mass spectrum of the first polymer; The first polymer has calculating at least one mass candidate for the non-main chain portion; and applying a Kendrick Mass Defect (KMD) analysis to the at least one mass candidate using the first repeating unit mass, thereby generating a first KMD analysis result; having a main chain portion different from the main chain portion of the first polymer; a second repeating unit mass determined from a second mass spectrum of a second polymer having the same non-main chain portion as the non-main chain portion of the first polymer; a second repeating unit mass different from the first repeating unit massand generating an image for identifying the mass of the non-main-chain portion or determining the mass of the non-main-chain portion based on the first KMD analysis result and the second KMD analysis result. Effect of the Invention
[0013] According to the present invention, the mass of the non-main chain portion in a polymer can be determined, or information for determining the mass of the non-main chain portion in a polymer can be provided. [Brief description of the drawings]
[0014] [Figure 1] FIG. 1 is a block diagram showing a polymer analysis system according to an embodiment. [Diagram 2] FIG. 2 is a schematic diagram showing the structures of polymers A and B. [Diagram 3] FIG. 2 : Derivatization. [Figure 4] FIG. 2 shows an example of a mass spectrum of a polymer A and a mass spectrum of a polymer B. [Diagram 5] 1 is a flowchart illustrating a method for creating a mass candidate list. [Figure 6] FIG. 13 is a diagram showing a first example of a mass candidate list. [Figure 7] FIG. 1 shows a first example of an image including two plots. [Figure 8] FIG. 13 is a diagram showing a first example of a graph. [Figure 9] FIG. 13 is a diagram showing an example of polymer analysis. [Figure 10] FIG. 13 is a diagram showing another example of a mass spectrum of a polymer. [Figure 11] FIG. 13 is a diagram showing a second example of a mass candidate list. [Figure 12] FIG. 13 shows a second example of an image including two plots. [Figure 13] FIG. 13 is a diagram showing a second example of a graph. [Figure 14]1 is a flowchart illustrating a polymer analysis method according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] Hereinafter, an embodiment will be described with reference to the drawings.
[0016] (1) Overview of the embodiment The polymer analysis apparatus according to the embodiment includes a processor that processes a first mass spectrum of a first polymer and a second mass spectrum of a second polymer having the same non-main chain portion as the non-main chain portion of the first polymer. The processor calculates at least one mass candidate for the non-main chain portion based on the first polymer molecular mass and the first repeating unit mass identified from the first mass spectrum, and applies a Kendrick Mass Defect (KMD) analysis using the first repeating unit mass to the at least one mass candidate, thereby generating a first KMD analysis result. Meanwhile, the processor applies a KMD analysis using a second repeating unit mass identified from the second mass spectrum to the second mass spectrum, thereby generating a second KMD analysis result. Then, the processor generates an image for identifying the mass of the non-main chain portion or determines the mass of the non-main chain portion based on the first KMD analysis result and the second KMD analysis result.
[0017] According to the above configuration, the mass of the non-main chain portion common to the first and second polymers can be identified by utilizing the special relationship between these polymers. More specifically, by applying KMD analysis to mass candidates calculated from the first mass spectrum, a feature quantity that is independent of the first repeat unit mass and dependent on the mass of the non-main chain portion is obtained. On the other hand, by applying KMD analysis to the second mass spectrum, a feature quantity that is independent of the second repeat unit mass and dependent on the mass of the non-main chain portion is obtained. By matching these feature quantities, the mass of the non-main chain portion common to the first and second polymers can be identified.
[0018] If the non-main chain portion does not contain an adduct ion, the mass of the non-main chain portion can be assumed to be the mass of the end group (usually the combined mass of the two end groups). If the non-main chain portion contains an adduct ion, the mass of the end group can be determined by subtracting the mass of the adduct ion from the mass of the non-main chain portion. The composition of the end group can be inferred from the mass of the end group.
[0019] In an embodiment, the processor generates a plot representing the second KMD analysis and generates a reference image representing the first KMD analysis, the reference image being added to the plot. The image includes the plot and the reference image. The content of the plot is compared to the reference image to narrow down the mass of the non-main chain moiety. The mass of the non-main chain moiety may be determined by a user or automatically. The mass of the non-main chain moiety may be automatically determined by directly matching the first KMD analysis result and the second KMD analysis result.
[0020] In an embodiment, the plot includes at least one of a nominal Kendrick mass (NKM) plot having an NKM axis and a KMD axis, and a remainder of Kendrick mass (RKM) plot having an RKM axis and a KMD axis. Both the NKM-KMD plot and the RKM-KMD plot have a KMD axis. KMD is a feature that does not depend on the mass of the repeat unit and depends on the mass of the non-main chain portion.
[0021] A number of types of KMDs have been proposed so far. These KMDs have in common that they do not depend on the mass of the repeating unit and depend on the mass of the non-main chain portion. In the embodiment, any KMD may be used. Similarly, a number of types of RKMs have been proposed so far. These RKMs have in common that they do not depend on the NKM. In the embodiment, any RKM may be used.
[0022] In an embodiment, the processor computes a plurality of mass candidates for the non-backbone moieties, and the reference image includes at least one of a first reference image including a plurality of figures representing a plurality of KMDs computed from the plurality of mass candidates and displayed on the NKM-KMD plot, and a second reference image including a plurality of figures representing a plurality of RKM-KMD sets computed from the plurality of mass candidates and displayed on the RKM-KMD plot.
[0023] Only one of the NKM-KMD plot and the RKM-KMD plot may be displayed. In that case, a reference image corresponding to the displayed plot is displayed. If both the NKM-KMD plot and the RKM-KMD plot are displayed, the polymer can be analyzed more appropriately. In that case, two reference images corresponding to the two displayed plots are displayed. In an embodiment, each figure in the first reference image has a linear form, and each figure in the second reference image has a circular form. Linear forms include transverse lines, short lines, arrows, bands, etc. Circular forms include circles, ellipses, enclosed figures, etc.
[0024] In an embodiment, the processor calculates a plurality of mass candidates by repeatedly subtracting the first repeating unit mass from the first polymer molecular mass. In an embodiment, the processor determines the remaining mass after subtraction as a mass candidate if the remaining mass falls within a specified mass range. The mass range is specified by a user or automatically specified according to various conditions.
[0025] In an embodiment, the processor repeats subtraction and calculation of the degree of polymerization, thereby creating a list in which a plurality of mass candidates and a plurality of corresponding degrees of polymerization are registered. With this configuration, it is possible to take into account a plurality of degrees of polymerization in the process of identifying the mass of the non-main chain portion from the plurality of mass candidates. Based on the contents of the list, a reference image is generated.
[0026] In an embodiment, the processor calculates the total ion intensity for each calculated KMD based on the second mass spectrum, and creates a graph showing a plurality of total ion intensities corresponding to the plurality of KMDs. With this configuration, the mass of the non-main chain portion can be determined from the relationship between the plot content and the reference image while taking into account the content of the graph. The graph is, for example, a bar graph.
[0027] In embodiments, one of the first polymer and the second polymer is a polymer before derivatization, and the other of the first polymer and the second polymer is a polymer after derivatization. Derivatization can be used to easily prepare two polymers that differ only in their backbone portions (i.e., they have non-backbone portions in common).
[0028] The polymer analysis method according to the embodiment includes a calculation step, a first analysis step, a second analysis step, and a processing step. In the calculation step, at least one mass candidate for the non-main chain portion is calculated based on the first polymer molecular mass and the first repeating unit mass identified from the first mass spectrum of the first polymer. In the first analysis step, a Kendrick mass defect (KMD) analysis using the first repeating unit mass is applied to the at least one mass candidate, thereby generating a first KMD analysis result. In the second analysis step, a KMD analysis using a second repeating unit mass identified from the second mass spectrum is applied to a second mass spectrum of a second polymer having the same non-main chain portion as the non-main chain portion of the first polymer, thereby generating a second KMD analysis result. In the processing step, an image for identifying the mass of the non-main chain portion is generated or the mass of the non-main chain portion is determined based on the first KMD analysis result and the second KMD analysis result.
[0029] The first analysis step may be performed prior to the second analysis step, the second analysis step may be performed prior to the first analysis step, or the first analysis step and the second analysis step may be performed simultaneously.
[0030] The polymer analysis method according to the embodiment further includes a preparation step in which one of the first polymer and the second polymer is derivatized, thereby preparing the other of the first polymer and the second polymer.
[0031] The polymer analysis method according to the embodiment may be realized by a hardware function or a software function. In the latter case, the polymer analysis program is installed in the information processing device via a network or via a portable storage medium. The information processing device has a non-transitory storage medium that stores the polymer analysis program, and also has a processor that executes the polymer analysis program. The processor may be configured with one or more physical devices. Some of the steps in the polymer analysis method according to the embodiment may be performed by a user. All or some of the steps in the polymer analysis method according to the embodiment may be performed as a service on a network.
[0032] (2) Detailed Description of the Embodiments (2-1)KMD analysis First, we explain the Kendrick mass defect (KMD) analysis. For a given polymer mass M, the Kendrick mass (KM) is defined as follows:
[0033] KM = M x Mri / M (1)
[0034] Here, Mri is the integer mass of the repeating unit, and Mr is the exact mass of the repeating unit. The integer mass of the former can be calculated from the exact mass of the latter. The exact mass is the mass including the decimal point.
[0035] The integer part of KM is defined as the Nominal Kendrick Mass (NKM). The Kendrick Mass Defect (KMD) is defined as the difference between NKM and KM as follows:
[0036] KMD = NKM - KM (2)
[0037] On the other hand, the mass M of a polymer can generally be expressed as follows:
[0038] M = Mr × n + Me + Mc (3)
[0039] Here, n is the degree of polymerization, Me is the mass of the end group (total mass of the two end groups), and Mc is the mass of the adduct ion (total mass of the adduct ions when multiple adduct ions are attached). On the right side of the above formula (3), (Mr×n) is the mass of the main chain portion, and (Me+Mc) is the mass of the portion other than the main chain portion (non-main chain portion).
[0040] By substituting the right-hand side of equation (3) for M in equation (1) above, KM can be expressed as follows:
[0041] KM = Mri xn + ( Me + Mc ) Mri / Mr (4)
[0042] Since the first term on the right hand side of the above equation (4) is an integer, it does not contribute to KMD. With this in mind, from the above equations (2) and (4), KMD can be expressed as follows:
[0043] KMD = Round { ( Me + Mc ) Mri / Mr} - ( Me + Mc ) Mri / Mr (5)
[0044] The first term on the right side of the above formula (5) is NKM. Round{} means rounding off. In the above formula (5), KMD takes a value within the range of -0.5 to +0.5. KMD does not depend on the degree of polymerization n. More specifically, KMD does not depend on the mass of the main chain portion and depends on the mass of the non-main chain portion. In KMD analysis, the above coefficient (Mri / Mr) is used to obtain a feature amount that does not depend on the mass of the main chain portion.
[0045] A NKM-KMD pair is calculated for each peak in the mass spectrum of the polymer. This results in multiple NKM-KMD pairs corresponding to multiple peaks. Multiple NKM-KMD pairs are expressed as multiple display elements on a two-dimensional coordinate system having an NKM axis and a KMD axis. This generates a KMD plot (more precisely, an NKM-KMD plot).
[0046] In the KMD plot, a plurality of display elements corresponding to a plurality of peaks generated from a certain polymer are arranged at equal intervals parallel to the horizontal axis. For example, each display element is a circle, and in this case, the diameter of each circle is determined according to the area (ionic intensity) of each peak. Note that KMDs that take values within the range of 0 to 1.0 are also known. Such KMDs may also be used in the embodiment.
[0047] Next, we will explain the Remainder of Kendrick Mass (RKM). The decimal part of the quotient obtained by dividing KM by Mri is RKM. Specifically, RKM is defined as follows:
[0048] RKM = KM / Mri - Floor ( KM / Mri ) (6)
[0049] Here, Floor( ) means rounding down.
[0050] By substituting the right-hand side of equation (4) for each KM in equation (6) above, we obtain the following equation (7).
[0051] RKM = ( n + ( Me + Mc ) / Mr ) - Floor ( n + ( Me + Mc ) / Mr ) (7)
[0052] In the above formula (7), n is an integer, so it can be removed. In the end, RKM is defined as follows:
[0053] RKM = ( Me + Mc ) / Mr - Floor ( ( Me + Mc ) / Mr ) (8)
[0054] In the mass spectrum obtained from a polymer, the set of values Me, Mc, and Mr calculated from each peak is the same. Therefore, multiple RKMs calculated from multiple peaks will be the same value. RKM takes a value in the range of 0 to 1.0. Another method of calculating RKM is known in which the remainder obtained when NKM is divided by Mri is defined as RKM. In this case, RKM takes a value in the range of 0 to Mri.
[0055] Generally, a RKM-KMD pair is identified for each peak in the mass spectrum of a polymer. This results in multiple RKM-KMD pairs corresponding to multiple peaks. Multiple RKM-KMD pairs are expressed as multiple display elements on a two-dimensional coordinate system having RKM and KMD axes. This generates a RKM-KMD plot. In the RKM-KMD plot, multiple display elements are displayed at the same position, and their polymerization states are generated. For example, each display element is a circle, and the diameter of the circle is changed according to the peak area (ion intensity).
[0056] (2-2) Polymer analysis system FIG. 1 shows a polymer analysis system according to an embodiment. The polymer analysis system is composed of a mass spectrometer 10 and a polymer analysis device 12. In the embodiment, the mass spectrometer 10 performs mass analysis on sample A and sample B. The polymer analysis device 12 has a function of identifying the mass of a non-main chain portion in a polymer. In the embodiment, the mass of a non-main chain portion common to the two polymers A and B is identified based on two analysis results for the two polymers A and B that are in a special relationship.
[0057] In the embodiment, sample A and sample B are each subject to mass spectrometry. Sample A contains polymer A, and sample B contains polymer B. For example, polymer B is prepared by derivatization of polymer A (see reference numeral 14). Prior to describing the configuration shown in FIG. 1, polymer A and polymer B will be described with reference to FIG. 2.
[0058] In the example shown in FIG. 2, each polymer molecule 16 constituting the polymer A is composed of a main chain portion 18, an end group 22, and an additional ion 24. The main chain portion 18 has a structure in which a plurality of repeating units 20 are linked together. One repeating unit 20 corresponds to a monomer molecule. The end group 22 is usually composed of two end groups 22a and 22b bonded to both ends of the main chain portion 18. For example, when the polymer A is treated with a cationizing agent, an additional ion 24 is attached to the main chain portion 18. The mass of the additional ion 24 is usually known. When the additional ion 24 is attached to the main chain portion 18, the end group 22 and the additional ion 24 constitute a non-main chain portion. When the additional ion 24 is not attached to the main chain portion 18, the end group 22 constitutes a non-main chain portion.
[0059] Polymer B is prepared by derivatization of polymer A. Polymer B may also be prepared by other methods. Each polymer molecule 26 constituting polymer B, like each polymer molecule constituting polymer A, is composed of a main chain portion 28, an end group 32, and an additional ion 34. The main chain portion 28 has a structure in which a plurality of repeating units 30 are linked together. The end group 32 usually consists of two end groups 32a and 32b. When the additional ion 34 is attached to the main chain portion 28, the end group 32 and the additional ion 34 are 34 constitutes the non-main chain portion. If no adduct ion 34 is attached to the main chain portion 28, then the end group 32 constitutes the non-main chain portion.
[0060] The main chain portion 18 (repeating unit 20) in polymer A and the main chain portion 28 (repeating unit 30) in polymer B are different from each other. On the other hand, the non-main chain portion in polymer A and the non-main chain portion in polymer B are identical to each other. There is a special relationship between polymer A and polymer B. A method for preparing two polymers in such a special relationship includes derivatization. However, two polymers in a special relationship may also be prepared by other methods.
[0061] An example of derivatization is shown in FIG. 3. Reference numeral 36 denotes a repeat unit in polymer A. Repeat unit 36 has OH (see reference numeral 38). Polymer B is prepared by applying a derivatization reagent to polymer A. Reference numeral 40 denotes a repeat unit in polymer B. Repeat unit 40 has OCH3 instead of OH. FIG. 3 shows methylation as an example of derivatization, but other derivatization methods may be used. Note that derivatization has the secondary advantage of improving ionization efficiency.
[0062] Returning to FIG. 1, the mass spectrometer 10 has an ion source 44, a mass analyzer 46, and a detector 48. A sample is ionized in the ion source 44. The ionization method in the ion source 44 includes soft ionization methods such as MALDI and ESI. The mass analyzer 46 is composed of, for example, a time-of-flight mass analyzer, a Fourier transform mass analyzer, or the like. These are capable of performing accurate mass analysis. Ions are detected in the detector 48. An output signal from the detector 48 is sent to the polymer analysis device 12 via a signal processing circuit (not shown).
[0063] In the mass spectrometer 10, for example, sample A is measured first, followed by sample B. The measurement order may be reversed. The two samples may be measured simultaneously, so long as the two spectra obtained from the two samples can be distinguished afterwards.
[0064] The polymer analysis device 12 is composed of an information processing device such as a computer. The polymer analysis device 12 has a processor (e.g., a CPU) that executes a program. In Fig. 1, a plurality of functions performed by the processor are represented by a plurality of blocks (see reference numeral 50). A display device 72 is connected to the processor, and an input device (not shown) is also connected to the processor.
[0065] The mass spectrum creating section 51 creates a mass spectrum based on the output signal from the detector 48. In this embodiment, the mass spectrum creating section 51 creates a mass spectrum of sample A and a mass spectrum of sample B in sequence.
[0066] For simplicity of explanation, in the following explanation, it is assumed that sample A contains only polymer A, and sample B contains only polymer B. In this case, mass spectrum creation unit 51 creates a mass spectrum of polymer A as the mass spectrum of sample A, and creates a mass spectrum of polymer B as the mass spectrum of sample B. Note that the case where sample A contains multiple polymers and sample B contains multiple polymers will be explained later with reference to FIG. 9 etc.
[0067] Mass spectrum data of polymer A and mass spectrum data of polymer B are sent from mass spectrum creation unit 51 to display 72 via display processing unit 52. The mass spectrum of polymer A and the mass spectrum of polymer B are displayed on the screen of display 72.
[0068] The NKM / KMD / RKM calculation unit 53 (hereinafter simply referred to as the calculation unit 53) applies KMD analysis to the mass spectrum of polymer A and the mass spectrum of polymer B, respectively. Specifically, the calculation unit 53 executes the above formula (5) to calculate KMD (and in the process also calculates NKM), and also executes the above formula (8) to calculate RKM. The precise mass Mr of the repeating unit is identified from the peak interval in the mass spectrum. The integer mass Mri of the repeating unit is identified from the precise mass Mr of the repeating unit. As a result of the KMD analysis, a feature set consisting of NKM, KMD, and RKM is obtained for each individual peak contained in each mass spectrum.
[0069] The NKM-KMD plot generating unit 54 generates an NKM-KMD plot for each mass spectrum. The NKM-KMD plot has a NKM axis as the horizontal axis and a KMD axis as the vertical axis. For each peak, a display element representing a set of NKM-KMD calculated from the peak is mapped onto a two-dimensional coordinate system defined by the NKM axis and the KMD axis, thereby generating an NKM-KMD plot. For example, each display element is a circle, and the diameter of the circle is determined from the area of each peak.
[0070] In the embodiment, an NKM-KMD plot for polymer A and an NKM-KMD plot for polymer B are generated. Data showing these plots are sent to the display 72 via the display processing unit 52. The NKM-KMD plot for polymer A and the NKM-KMD plot for polymer B are displayed on the screen of the display 72.
[0071] The RKM-KMD plot generating unit 55 generates an RKM-KMD plot for each mass spectrum. The RKM-KMD plot has an RKM axis as the horizontal axis and a KMD axis as the vertical axis. For each peak, a display element representing a RKM-KMD pair calculated from the peak is mapped onto a two-dimensional coordinate system defined by the RKM axis and the KMD axis, thereby generating the RKM-KMD plot. For example, each display element is a circle, and the diameter of the circle is determined from the area of each peak.
[0072] In an embodiment, the RKM-KMD plot for polymer A and the RKM-KMD plot for polymer B are RKM The RKM-KMD plots for polymer A and polymer B are generated. Data showing these plots are sent to the display 72 via the display processing unit 52. The RKM-KMD plot for polymer A and the RKM-KMD plot for polymer B are displayed on the screen of the display 72.
[0073] In an embodiment, in identifying the mass of the non-main chain portion, at least one of the NKM-KMD plot and the RKM-KMD plot for polymer B is displayed. A reference image described below is displayed on the displayed plot. Desirably, both the NKM-KMD plot and the RKM-KMD plot for polymer B are displayed, and two reference images described below are displayed on the two plots.
[0074] The mass candidate list creation unit 56 (hereinafter simply referred to as the list creation unit 56) creates a mass candidate list including a plurality of mass candidates. Specifically, the list creation unit 56 identifies a polymer molecular mass from any peak contained in the mass spectrum of polymer A, and identifies a repeating unit mass based on the mass spectrum of polymer A. Then, the list creation unit 56 repeatedly subtracts the repeating unit mass from the polymer molecular mass. If the remaining mass after subtraction falls within a specified mass range, the list creation unit 56 determines that the remaining mass is a mass candidate. In identifying the polymer molecular mass, a peak may be specified by the user or automatically.
[0075] The mass range is designated in advance by the user (see reference numeral 58) or automatically. The mass range may be designated based on the expected upper and lower limit masses of the non-main chain portion. In an embodiment, the list creation unit 56, in the process of repeatedly subtracting the repeating unit mass from the polymer molecular mass, Degree of polymerization The calculation of is also repeated. A plurality of mass candidates and a plurality of corresponding degrees of polymerization are registered in the mass candidate list. The degree of polymerization is calculated from the number of times the unit mass is repeatedly subtracted.
[0076] The KMD / RKM calculation unit 60 (hereinafter simply referred to as the calculation unit 60) applies KMD analysis to multiple mass candidates included in a mass candidate list created from the mass spectrum of polymer A, thereby calculating a KMD-RKM pair for each mass candidate. As a result, multiple KMD-RKM pairs corresponding to multiple mass candidates are obtained. Specifically, the calculation unit 60 executes the following calculations.
[0077] When calculating KMD for a mass candidate MEi, the following equation (9) is executed.
[0078] KMD = Round { MEi x Mri / M r} - MEi x Mri / M r (9)
[0079] Here, Mri is the integer mass of the repeating unit in polymer A, and Mr is the exact mass of the repeating unit in polymer A. Round ( ) indicates rounding off.
[0080] When calculating RKM for mass candidate MEi, the following equation (10) is executed.
[0081] RKM = MEi / Mr - Floor( MEi / Mr ) (10)
[0082] Here, Floor ( ) indicates truncation to the nearest integer.
[0083] The above formula (9) is the same as the above formula (5) except for the difference in the mass of the object of analysis. Similarly, the above formula (10) is the same as the above formula (8) except for the difference in the mass of the object of analysis.
[0084] The reference image generation unit 62 has a first function of generating a first reference image (first graphics) based on a plurality of KMDs obtained from a plurality of mass candidates, and a second function of generating a second reference image (second graphics) based on a plurality of KMD-RKM pairs obtained from a plurality of mass candidates.
[0085] The display processing unit 52 synthesizes the first reference image on the NKM-KMD plot, and synthesizes the second reference image on the RKM-KMD plot. On the screen of the display 72, the NKM-KMD plot with the first reference image added is displayed, and the RKM-KMD plot with the second reference image added is displayed. In the embodiment, an image including these plots is displayed on the display 72. As will be described in detail later, the mass of the non-main chain portion can be identified by comparing the contents of the NKM-KMD plot with the first reference image. Similarly, the mass of the non-main chain portion can be identified by comparing the contents of the RKM-KMD plot with the second reference image.
[0086] The graph generating unit 64 generates a graph to assist in identifying the non-main chain portion, as will be described later.
[0087] A determination unit 74 may be provided in the display processing unit 52. The determination unit 74 compares the first KMD analysis result output from the calculation unit 60 with the second KMD analysis result output from the calculation unit 53, thereby identifying the mass of the non-main chain portion. In this case, the first KMD analysis result may be directly compared with the second KMD analysis result (see reference numerals 200 and 202), or a reference image showing the first KMD analysis result may be compared with a plot showing the second KMD analysis result.
[0088] The mass selection unit 66 selects a specific mass candidate from among a plurality of mass candidates as the mass of the non-main chain portion. The specific mass candidate may be designated by a user (see reference numeral 68) or may be designated by the determination unit 74 (see reference numeral 204).
[0089] When the non-main chain portion contains an adduct ion, the composition estimation unit 70 subtracts the mass Mc of the adduct ion from the mass of the non-main chain portion, thereby identifying the mass (precise mass) of the terminal group. Then, the composition estimation unit 70 estimates the composition of the terminal group based on the mass of the terminal group. When the non-main chain portion does not contain an adduct ion, the composition estimation unit 70 regards the mass of the non-main chain portion as the mass of the terminal group, and estimates the composition of the terminal group based on that mass. The display 72 displays the result of the composition estimation.
[0090] FIG. 4 illustrates a mass spectrum 76 obtained from polymer A and a mass spectrum 78 obtained from polymer B. When identifying mass candidates, a specific peak is specified by the user in the mass spectrum 76 (see reference numeral 80). The mass (precise mass) M of the polymer molecule is identified based on the m / z corresponding to the specific peak. The mass (precise mass) Mr of the repeating unit is identified from the magnitude between the peaks in the mass spectrum 76. Similarly, the mass (precise mass) of the repeating unit is identified from the magnitude between the peaks in the mass spectrum 78.
[0091] 5 shows the operation of the list creation unit. In S10, a mass range is accepted. In this case, the upper and lower limits for the mass of the non-main chain portion may be specified by the user. In S12, a specific peak in the mass spectrum of polymer A is selected by the user. This identifies the mass M of the polymer molecule. At the same time, the mass Mr of the repeating unit for polymer A is identified.
[0092] In S14, the mass Mr of the repeating unit is subtracted from the mass M of the polymer molecule. In S16, the remaining mass resulting from the subtraction is compared to the mass range. If the remaining mass does not reach the mass range (if remaining mass > mass range), S12 is executed again. If the remaining mass falls within the mass range (if remaining mass ⊂ mass range), S18 is executed, in which the remaining mass is determined as a mass candidate and the mass candidate is added to a mass candidate list. If the remaining mass falls below the lower limit of the mass range (if remaining mass < mass range), the process ends.
[0093] The subtraction in S14 is repeated until the end of this process. That is, the mass Mr of the repeating unit is repeatedly subtracted from the mass M of the polymer molecule. Among the multiple remaining masses obtained in this process, those belonging to the mass range are determined as mass candidates. In the embodiment, the list creation unit has a function of calculating the degree of polymerization. The degree of polymerization calculated for each mass candidate is also registered in the mass candidate list. The degree of polymerization can be easily identified from the number of times the subtraction is repeated.
[0094] FIG. 6 shows a first example of a mass candidate list. The mass candidate list 80 has a plurality of records 82. One record 82 corresponds to one mass candidate. The record 82 includes information indicating an index 84, a mass candidate 86, and a degree of polymerization 88. By repeating the subtraction process shown in FIG. 5, the degree of polymerization 88 changes stepwise in FIG. 6. In the example shown, when the index 84 changes by one, the degree of polymerization 88 decreases by one. Specifically, the degree of polymerization 88 changes from N1 to N2 (=N1-1), to N3 (=N1-2).
[0095] FIG. 7 shows an NKM-KMD plot 90 and an RKM-KMD plot 92. A mass spectrum may be displayed together with these plots 90 and 92. In the NKM-KMD plot 90, the horizontal axis is the NKM axis, and the vertical axis is the KMD axis. The NKM-KMD plot 90 includes a display element column 94 showing the KMD analysis results for polymer B. The display element column 94 is composed of a plurality of display elements 96 corresponding to a plurality of peaks included in the mass spectrum of polymer B. Each display element 96 is a circle, and its diameter represents the peak area. The display elements constituting the display element column 94 are arranged at equal intervals parallel to the NKM axis.
[0096] A first reference image 98 generated from the mass spectrum of polymer A is displayed on the NKM-KMD plot 90. In the illustrated example, the first reference image 98 includes a plurality of lines 100, 102, 104 as a plurality of figures corresponding to a plurality of mass candidates. Specifically, the plurality of lines 100, 102, 104 are displayed at a plurality of vertical positions corresponding to a plurality of KMDs obtained from a plurality of mass candidates. An index is displayed near each of the lines 100, 102, 104. A degree of polymerization may also be displayed near each of the lines 100, 102, 104.
[0097] On the other hand, in the RKM-KMD plot 92, the horizontal axis is the RKM axis and the vertical axis is the KMD axis. The RKM-KMD plot 92 includes a display element group 114 showing the KMD analysis results for polymer B. The display element group 114 is composed of a plurality of display elements corresponding to a plurality of peaks included in the mass spectrum of polymer B. However, these are multiplexed and displayed at the same position, and appear to constitute a single display element. Each display element is a circle, and its diameter represents the peak area.
[0098] A second reference image 106 generated from the mass spectrum of polymer A is displayed on the RKM-KMD plot 92. In the illustrated example, the second reference image 106 includes a plurality of circles 108, 110, 112 as a plurality of figures corresponding to a plurality of mass candidates. Specifically, the plurality of circles 108, 110, 112 are displayed at a plurality of coordinates corresponding to a plurality of RKM-KMD pairs obtained from a plurality of mass candidates. The diameters of the circles 108, 110, 112 are the same. Specifically, each circle has a size larger than the maximum size of the display element group. Other surrounding figures may be adopted. An index is displayed near each circle 108, 110, 112. A degree of polymerization may be further displayed near each circle 108, 110, 112.
[0099] In the NKM-KMD plot 90, when one looks vertically, the display element column 94 coincides with the line 100. This coincidence indicates that, among the multiple mass candidates, the mass candidate corresponding to index #1 corresponds to the mass of the non-main-chain portion. In the RKM-KMD plot 92, the display element group 114 belongs to the circle 108. This inclusion relationship indicates that, among the multiple mass candidates, the mass candidate corresponding to index #1 corresponds to the mass of the non-main-chain portion.
[0100] As described above, the mass of the non-main chain portion can be easily determined by comparing the first reference image 98 derived from polymer A with the NKM-KMD plot 90 derived from polymer B. Similarly, the mass of the non-main chain portion can be easily determined by comparing the second reference image 106 derived from polymer A with the RKM-KMD plot 92 derived from polymer B.
[0101] Only one of the NKM-KMD plot 90 and the RKM-KMD plot 92 may be displayed. In that case, a reference image corresponding to the displayed plot is displayed. By displaying both the NKM-KMD plot 90 and the RKM-KMD plot 92 and both the first reference image 98 and the second reference image 106, the mass of the non-main chain portion can be determined more accurately. Two reference images may be generated from the mass spectrum of polymer B, and two plots may be generated from the mass spectrum of polymer A.
[0102] Graph 116 is shown as an auxiliary image in Fig. 8. In the RKM-KMD plot 92 shown in Fig. 7, the graph 116 is created by calculating the sum of the areas of one or more peaks belonging to each of the circles 108, 110, and 112. In the illustrated example, graph 116 has a bar 118 corresponding to index #1. The height of the bar corresponds to the total peak area. Graph 116 is referenced to identify the mass of the non-main chain portion.
[0103] FIG. 9 shows an example of practical polymer analysis. As indicated by reference numeral 120, sample A contains multiple polymers. Among them, polymer A1 and polymer A2 are the respective objects of analysis. As indicated by reference numeral 122, sample B also contains multiple polymers. Among them, polymer B1 and polymer B2 are the respective objects of analysis. Polymer A1 and polymer B1 are in the special relationship described above (see reference numeral 124). Polymer A2 and polymer B2 are also in the special relationship described above (see reference numeral 126).
[0104] Mass spectrometry of sample A results in a mass spectrum 128, which includes multiple peak series corresponding to multiple polymers. Among them, peak series a1 is a peak series of polymer A1, and peak series a2 is a peak series of polymer A2. A peak series is made up of multiple peaks spaced at equal intervals.
[0105] Mass spectrometry of sample B results in mass spectrum 130, which includes multiple peak series corresponding to multiple polymers, of which peak series b1 is the peak series of polymer B1 and peak series b2 is the peak series of polymer B2.
[0106] A KMD analysis may be applied to the mass spectrum to identify or extract each peak series, and an NKM-KMD plot or a RKM-KMD plot may be generated based on the results (see reference numeral 132). When a user specifies a display element sequence in the NKM-KMD plot, a particular peak series associated with the display element sequence is automatically identified. Similarly, when a user specifies a display element group in the RKM-KMD plot, a particular peak series associated with the display element group is automatically identified.
[0107] A first mass candidate list 134 is generated by subtracting the mass of a particular peak in the peak series a1 (see FIG. 5). A second mass candidate list 136 is generated by subtracting the mass of a particular peak in the peak series a2 (see FIG. 5). The first mass candidate list 134 and the second mass candidate list 136 may be integrated to form a single mass candidate list 138. A KMD analysis is applied to the mass candidates in the first mass candidate list 134, and a first reference image is generated based on the KMD analysis results (see reference numeral 140). A KMD analysis is applied to the mass candidates in the second mass candidate list 136, and a second reference image is generated based on the KMD analysis results (see reference numeral 140).
[0108] On the other hand, by applying KMD analysis to the mass spectrum 130 of sample B, the NKM-KMD plot 142 and R A KM-KMD plot 144 is generated. A first reference image is synthesized with the NKM-KMD plot 142, RA second reference image is synthesized with the KM-KMD plot 144. By matching the content of the RKM-KMD plot 142 with the first reference image, a user can recognize that a particular mass candidate is a non-main chain mass. Similarly, by matching the content of the RKM-KMD plot 144 with the second reference image, a user can recognize that a particular mass candidate is a non-main chain mass.
[0109] When the mass of the non-main chain portion is determined, the mass of the end group is determined from the mass of the non-main chain portion, taking into consideration the presence or absence of an adduct ion and the mass of the adduct ion. The composition of the end group is estimated based on the mass of the end group (see reference numeral 146).
[0110] 10 illustrates a mass spectrum 131. The mass spectrum 131 is the mass spectrum of sample A or the mass spectrum of sample B. The mass spectrum 131 includes multiple peak series corresponding to multiple polymers.
[0111] An example of the mass candidate list 138 is shown in Figure 11. The mass candidate list 138 is made up of a first mass candidate list 134 created from the peak series a1, and a second mass candidate list 136 created from the peak series a2. By repeating the subtraction process shown in Figure 5, the degree of polymerization changes stepwise for each peak series (polymer series) in Figure 11. In the example shown, when the index changes by one, the degree of polymerization decreases by one. Specifically, in the first mass candidate list 134, the degree of polymerization is N 11 , N 12 (=N 11 -1), N 13 (=N 11 In the second mass candidate list 136, the degree of polymerization is changed as follows: N 21 , N 22 (=N 21 -1), N 23 (=N 21 -2) has changed.
[0112] FIG. 12 shows an NKM-KMD plot 142 generated from the KMD analysis results of the mass spectrum of sample B and RKM -KMD plot 144 is illustrated. 12 In the figure 11 1 shows a first reference image 154 and a second reference image 156 generated from the results of a KMD analysis of a number of candidate masses in the mass candidate list 138 shown in FIG.
[0113] NKM-KMD plot 142 contains multiple vertical columns of display elements. 142 In reality, there may be many more display element columns in the NKM-KMD plot, but only the main display element columns are depicted in Fig. 12. The first reference image 154 has multiple arrows 155 corresponding to multiple mass candidates. 142 A plurality of indexes are displayed near the plurality of arrows 155. By comparing the positions of the plurality of display element columns with the positions of the plurality of arrows 155, a plurality of mass candidates can be evaluated.
[0114] In the illustrated example, for example, it can be recognized that three mass candidates corresponding to indexes #11, #12, and #13 may correspond to the mass of the non-main chain portion. In addition, it can be recognized that two mass candidates corresponding to indexes #22 and #23 may correspond to the mass of the non-main chain portion. When multiple mass candidates are found, one of the mass candidates may be selected as the mass of the non-main chain portion, taking into consideration the total ion intensity. Alternatively, it can be assumed that derivatization was not performed 100%, and the mass candidate corresponding to the largest degree of polymerization may be selected as the mass of the non-main chain portion.
[0115] For example, the degree of polymerization when all repeating units are derivatized is n m If one of the repeating units is not derivatized, the degree of polymerization is one smaller, n m-1 Therefore, when multiple mass candidates are found, the mass candidate corresponding to the largest degree of polymerization can be selected.
[0116] RKM-KMD plot 144 includes a plurality of display element groups. R KM-KMD plot 144 In reality, more display elements may be included in the second reference image 156, but only the main display elements are depicted in Fig. 12. The second reference image 156 has a number of circles 160-170 corresponding to a number of mass candidates. The circles 160, 162, and 164 are generated based on the first mass candidate list, and the circles 166, 168, and 170 are generated based on the second mass candidate list. An index is displayed near each of the circles 160-170.
[0117] By comparing the positions of the plurality of display element groups with the positions of the plurality of circles 160 to 170, a plurality of mass candidates can be evaluated. The three circles 160, 162, and 164 all include display element groups. In such a case, as described above, any of the mass candidates may be selected as the mass of the non-main chain portion, taking into consideration the total ionic strength. Alternatively, the mass candidate corresponding to the largest degree of polymerization may be selected as the mass of the non-main chain portion. On the other hand, among the three circles 166, 168, and 170, the circle 168 and 170 include display element groups. In such a case, as described above, any of the mass candidates may be selected as the mass of the non-main chain portion, taking into consideration the total ionic strength. Alternatively, the mass candidate corresponding to the largest degree of polymerization may be selected as the mass of the non-main chain portion.
[0118] Another example of a graph is shown in Figure 13. For example, the RKM-KMD plot shown in Figure 12 144 For each circle in, the peak series ascribed to it is identification The total area of the peak series is calculated. Based on the total peak areas obtained from the peak series, a graph 172 shown in Fig. 13 is created. On the graph 172, a specific index may be specified for each polymer by the user (see reference numerals 174 and 176). In other words, the mass of the non-main chain portion may be selected for each polymer.
[0119] 14 is a flow chart showing a polymer analysis method according to an embodiment. In S20, sample B is prepared by derivatization of sample A. In S22, mass spectrometry is performed on each of samples A and B. This produces a mass spectrum of sample A and a mass spectrum of sample B.
[0120] In S24, based on the results of the KMD analysis of the mass spectrum of sample A, the NKM-KMD plot and RKM -KMD plot In S26, the NKM-KMD plot and RKM -KMD plot In step S26, an analysis target is specified. That is, a specific peak series contained in the mass spectrum of sample A is specified. In step S28, a mass candidate list is created based on the specific peak series. A first reference image and a second reference image are generated based on the KMD analysis result for the mass candidate list.
[0121] On the other hand, in S30, the NKM-KMD plot and RKM -KMD plot is created. In S32, The NKM-KMD plot and the first reference image are displayed, and the RKM-KMD plot and the second reference image are displayed. Comparison of the NKM-KMD plot with the first reference image, and RKM The mass of the non-main chain portion is identified by comparing the -KMD plot with the second reference image. In S36, the mass of the end group is identified based on the mass of the non-main chain portion, and the composition of the end group is analyzed from the mass of the end group.
[0122] The above S30 may be executed prior to the above S24 to S28. In S28, a mass candidate list is created from the mass spectrum of sample B, and in S30, an NKM-KMD plot and RKM -KMD plot may be created. [Explanation of symbols]
[0123] 10 mass spectrometer, 12 polymer analyzer, 51 mass spectrum creation unit, 53 NKM / KMD / RKM calculation unit, 54 NKM-KMD plot generation unit, 55 RKM-KMD plot generation unit, 56 mass candidate list creation unit, 60 KMD / RKM calculation unit, 62 reference image generation unit, 64 graph generation unit, 66 mass selection unit, 70 composition estimation unit.
Claims
1. a processor for processing a first mass spectrum of a first polymer and a second mass spectrum of a second polymer having a backbone portion different from the backbone portion of the first polymer and having a non-backbone portion the same as the backbone portion of the first polymer; The processor, calculating at least one mass candidate for the non-main chain portion based on a first polymer molecular mass and a first repeating unit mass identified from the first mass spectrum; applying a Kendrick mass defect (KMD) analysis to the at least one mass candidate using the first repeating unit mass, thereby generating a first KMD analysis result; applying a KMD analysis to the second mass spectrum using a second repeating unit mass identified from the second mass spectrum, the second repeating unit mass being different from the first repeating unit mass, thereby generating a second KMD analysis result; generating an image for identifying the mass of the non-main chain portion or determining the mass of the non-main chain portion based on the first KMD analysis result and the second KMD analysis result; A polymer analysis device characterized by:
2. 2. The polymer analysis apparatus according to claim 1, The processor, generating a plot representative of the second KMD analysis; generating a reference image representative of the first KMD analysis result, the reference image being added to the plot; A polymer analysis device characterized by:
3. 3. The polymer analysis apparatus according to claim 2, the plot includes at least one of a Nominal Kendrick Mass (NKM) plot having an NKM axis and a KMD axis, and a Remainer of Kendrick Mass (RKM) plot having an RKM axis and a KMD axis; A polymer analysis device characterized by:
4. 4. The polymer analysis apparatus according to claim 3, The processor calculates a plurality of mass candidates for the non-backbone moieties; The reference image includes at least one of a first reference image including a plurality of figures representing a plurality of KMDs calculated from the plurality of mass candidates and displayed on the NKM-KMD plot, and a second reference image including a plurality of figures representing a plurality of RKM-KMD sets calculated from the plurality of mass candidates and displayed on the RKM-KMD plot. A polymer analysis device characterized by:
5. A method for producing a mixture of a first polymer and a second polymer, the method comprising: a processor for processing a first mass spectrum of a first polymer and a second mass spectrum of a second polymer having the same non-main-chain portion as the first polymer; The processor, calculating a plurality of mass candidates for the non-main chain portion by repeatedly subtracting the first repeating unit mass from the first polymer molecular mass based on the first polymer molecular mass and the first repeating unit mass identified from the first mass spectrum; applying a Kendrick mass defect (KMD) analysis to the plurality of mass candidates using the first repeating unit mass, thereby generating a first KMD analysis result; applying a KMD analysis to the second mass spectrum using a second repeating unit mass identified from the second mass spectrum, thereby generating a second KMD analysis result; generating an image for identifying the mass of the non-main chain portion or determining the mass of the non-main chain portion based on the first KMD analysis result and the second KMD analysis result; A polymer analysis device characterized by:
6. 6. The polymer analysis apparatus according to claim 5, The processor determines the residual mass after subtraction as a mass candidate if the residual mass falls within a specified mass range. A polymer analysis device characterized by:
7. 6. The polymer analysis apparatus according to claim 5, The processor repeats the subtraction and the calculation of the degree of polymerization, thereby creating a list in which the plurality of mass candidates and the plurality of degrees of polymerization corresponding thereto are registered. A polymer analysis device characterized by:
8. A method for producing a mixture of a first polymer and a second polymer, the method comprising: a processor for processing a first mass spectrum of a first polymer and a second mass spectrum of a second polymer having the same non-main-chain portion as the first polymer; The processor, calculating at least one mass candidate for the non-main chain portion based on a first polymer molecular mass and a first repeating unit mass identified from the first mass spectrum; applying a Kendrick mass defect (KMD) analysis to the at least one mass candidate using the first repeating unit mass, thereby generating a first KMD analysis result; applying a KMD analysis to the second mass spectrum using a second repeating unit mass identified from the second mass spectrum, thereby generating a second KMD analysis result; generating an image for identifying the mass of the non-main chain portion or determining the mass of the non-main chain portion based on the first KMD analysis result and the second KMD analysis result; Calculating a total ion intensity for each calculated KMD based on the second mass spectrum, thereby creating a graph showing a plurality of total ion intensities corresponding to a plurality of KMDs. A polymer analysis device characterized by:
9. A method for detecting a molecular weight change in a polymer, comprising: a processor for processing a first mass spectrum of a first polymer and a second mass spectrum of a second polymer having the same non-main-chain portion as the first polymer; The processor, calculating at least one mass candidate for the non-main chain portion based on a first polymer molecular mass and a first repeating unit mass identified from the first mass spectrum; applying a Kendrick mass defect (KMD) analysis to the at least one mass candidate using the first repeating unit mass, thereby generating a first KMD analysis result; applying a KMD analysis to the second mass spectrum using a second repeating unit mass identified from the second mass spectrum, thereby generating a second KMD analysis result; generating an image for identifying the mass of the non-main chain portion or determining the mass of the non-main chain portion based on the first KMD analysis result and the second KMD analysis result; one of the first polymer and the second polymer is a pre-derivatized polymer; the other of the first polymer and the second polymer is a derivatized polymer; A polymer analysis device characterized by:
10. calculating at least one mass candidate for a non-main chain portion of the first polymer based on a first polymer molecular mass and a first repeating unit mass identified from a first mass spectrum of the first polymer; applying a Kendrick Mass Defect (KMD) analysis to the at least one mass candidate using the first repeating unit mass, thereby generating a first KMD analysis result; applying a KMD analysis to a second mass spectrum of a second polymer having a main chain portion different from the main chain portion of the first polymer and having the same non-main chain portion as the non-main chain portion of the first polymer, using a second repeating unit mass identified from the second mass spectrum, the second repeating unit mass being different from the first repeating unit mass, thereby generating a second KMD analysis result; generating an image for identifying the mass of the non-main chain portion or determining the mass of the non-main chain portion based on the first KMD analysis result and the second KMD analysis result; A polymer analysis method comprising:
11. The polymer analysis method according to claim 10, preparing one of the first polymer and the second polymer by derivatizing the other of the first polymer and the second polymer; A polymer analysis method comprising:
12. A program for performing polymer analysis in an information processing device, a function of calculating at least one mass candidate for a non-main chain portion of the first polymer based on a first polymer molecular mass and a first repeating unit mass identified from a first mass spectrum of the first polymer; applying a Kendrick Mass Defect (KMD) analysis to the at least one mass candidate using the first repeating unit mass, thereby generating a first KMD analysis result; a function of applying a KMD analysis to a second mass spectrum of a second polymer having a main chain portion different from the main chain portion of the first polymer and having the same non-main chain portion as the non-main chain portion of the first polymer, using a second repeating unit mass identified from the second mass spectrum, the second repeating unit mass being different from the first repeating unit mass, thereby generating a second KMD analysis result; a function of generating an image for identifying the mass of the non-main chain portion or determining the mass of the non-main chain portion based on the first KMD analysis result and the second KMD analysis result; A program comprising:
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