Compound isotope distribution detection method
By constructing an element database and calculating the molecular isotope mass and abundance of compounds, the accuracy and efficiency problems when detecting the isotope distribution of compounds in the prior art are solved, and fast and accurate isotope distribution detection is achieved.
Patent Information
- Application Number
- CN202411957966.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-30
- Publication Date
- 2025-04-04
AI Technical Summary
When detecting the isotope distribution of compounds, the prior art is susceptible to instrument fluctuations, the operation is complex and the calculation time is long, especially for molecules with larger mass, the simulation results are relatively unstable.
By constructing an element database, it contains the isotope mass and abundance of all elements, extract the elements and numbers to be tested according to the chemical formula of the compound to be tested, calculate the atomic mass and abundance of each element to be tested, and combine the atomic mass and abundance of all elements to obtain the molecular isotope mass and abundance of the compound.
It realizes rapid and accurate detection of the isotope distribution of compounds, and is suitable for different types of compounds, simplifies the calculation process, and improves detection efficiency and accuracy.
Smart Images
Figure CN119763719A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of chemical analysis, and in particular relates to a method for detecting isotope distribution of a compound. Background Art
[0002] In chemical fields such as biological metabolism, environmental monitoring and mass spectrometry, isotope distribution is one of the important indicators for compound analysis. For example, in the environmental field, the unique isotope distribution property can help identify unknown small molecule compounds. In the biological field, isotope distribution can help find biological metabolites. At present, isotope distribution is usually calculated by experiment or software simulation calculation. The experimental method is mainly to inject compound standards into the mass spectrometer to show the molecular isotope distribution in the mass spectrum. However, the result is easily affected by instrument fluctuations, and the instrument operation time is long and the technology is complex. The simulation software disclosed on the Internet adopts the random distribution mode in statistics, and calculates the molecular mass by weight according to the different atomic isotope masses and abundances, and then repeatedly calculates thousands or even tens of thousands of atoms to obtain the isotope distribution map. However, this method has a good effect on compounds with a mass of less than 100, but for molecules with larger mass, the isotope distribution simulation is less stable and cannot reflect the actual results well, and the more molecules are repeatedly calculated, the longer and more complicated the calculation time is.
[0003] Therefore, there is an urgent need for a detection method that is more accurate and efficient than existing methods, which can quickly and accurately obtain the results of the isotope distribution of compounds and provide a more efficient analytical tool for chemical research and related fields. Summary of the invention
[0004] The technical problem to be solved by the present invention is to provide a method for detecting the isotope distribution of a compound, which can quickly and accurately detect the isotope distribution of a compound.
[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions: The present invention provides a method for detecting isotope distribution of a compound, comprising the following steps: Step 10, constructing an element database; the element database includes the mass and abundance of isotopes of all elements in the periodic table; Step 20, extracting and obtaining the elements and their numbers according to the chemical formula of the compound to be tested; Step 30, based on the element database, according to the elements and their number to be measured, respectively obtain the mass and abundance of the atomic group of each element to be measured; Step 40, combining the masses and abundances of the atomic groups of all the elements to be tested to obtain the masses and abundances of the molecular isotopes of the compound to be tested.
[0006] As a further improvement of the present invention, in step 30, obtaining the mass and abundance of the atomic group of the element α to be measured specifically includes: Search the element database and find that the element α to be tested has n isotopes, namely α 1 , α 2 , …, α n , the corresponding masses are Iso 1 , Iso 2 、…、Iso n , the abundances are x 1 、x 2 , …, x n ; n represents an integer greater than or equal to 1; Use formula (1) to calculate the mass of each atomic group of the element α to be measured: Formula (1) In the formula, represents the mass of the i-th atomic group of the element α to be measured, represents the isotope α in the i-th atomic group of the element α to be measured 1 The number of represents the isotope α in the i-th atomic group of the element α to be measured 2 The number of represents the isotope α in the i-th atomic group of the element α to be measured n The number of ; m represents the number of elements α to be measured.
[0007] As a further improvement of the present invention, in step 30, the abundance of each atomic group of the element α to be measured is calculated using a polynomial distribution formula.
[0008] As a further improvement of the present invention, the polynomial distribution formula is expressed as formula (2): Formula (2) In the formula, represents the abundance of the ith atomic group of the element α to be measured, Represents polynomial coefficients.
[0009] As a further improvement of the present invention, the step 40 specifically includes: Combine all the atomic groups of the elements to be tested to obtain molecular isotopes; add up the masses of all the atomic groups in each molecular isotope to obtain the mass of each molecular isotope; multiply the abundances of all the atomic groups in each molecular isotope to obtain the abundance of each molecular isotope.
[0010] As a further improvement of the present invention, in step 30, after obtaining the masses and abundances of all atomic groups of the element to be measured, atomic groups with abundances lower than 0.05% are removed.
[0011] As a further improvement of the present invention, in step 40, after obtaining the masses and abundances of all molecular isotopes of the compound to be tested, molecular isotopes with abundances lower than 0.01% are removed.
[0012] As a further improvement of the present invention, it also includes: Step 50, visualizing the mass and abundance of the molecular isotopes of the test compound to obtain a molecular isotope distribution map of the test compound.
[0013] Compared with the prior art, the technical solution of the present invention has the following beneficial effects: (1) The present invention provides a method for detecting the isotope distribution of a compound. Different isotopes of the same element to be tested in the compound to be tested are combined according to the number of the element to be tested to obtain the atomic groups of the element to be tested, and then the mass and abundance of each atomic group of the element to be tested are calculated, thereby obtaining the mass and abundance of all atomic groups of all elements to be tested in the compound to be tested, and finally different atomic groups of different elements to be tested are combined to obtain the mass and abundance of the molecular isotopes of the compound to be tested. The method of the present invention is applicable to the isotope distribution detection of different types of compounds, and the method of the present invention can accurately obtain the detection results for small molecules, macromolecules and complex compounds. The method of the present invention is based on simple and practical statistical principles such as polynomial distribution calculation. The distribution of atomic groups of each element is calculated and then combined together to obtain the theoretical isotope distribution, which simplifies the code calculation amount and does not need to rely on manual experience analysis, thereby improving the accuracy of isotope distribution detection and improving detection efficiency.
[0014] (2) The element database constructed by the method of the present invention includes the mass and abundance of isotopes of all elements in the periodic table, which serves as a reliable basis for detecting isotope distribution and further improves the accuracy of detection. At the same time, the element database can be expanded according to the results of new element discovery research, so that it can be used to detect new types of compounds beyond inherent limitations. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 is a flow chart of the compound isotope distribution detection method of the present invention; Figure 2 It is the compound C detected in Example 2 12 Br 10 Isotope abundance diagram of Figure 3 Compound C obtained by comparative example 1 12 Br 10 Isotope abundance diagram of Figure 4 Compound C obtained by comparative example 2 12 Br 10Isotope abundance diagram. DETAILED DESCRIPTION
[0016] The technical solution of the present invention is described in detail below.
[0017] The present invention provides a method for detecting the isotope distribution of a compound, such as Figure 1 As shown, the following steps are included: Step 10: construct an element database, which includes the mass and abundance of isotopes of all elements in the periodic table.
[0018] Specifically, the mass and abundance of the isotopes of all elements in the periodic table are obtained from the PubChem database to construct an element database. For example, hydrogen has two isotopes: 1 H and 2 H, the masses are 1.007825 amu and 2.014102 amu, and the abundances are 0.999885 and 0.000115, respectively.
[0019] Step 20, extract the elements and their number according to the chemical formula of the compound to be tested. For example, the chemical formula of the compound to be tested, 4,5-dibromo-1,2-dimethoxybenzene, is C 8 H 8 Br 2 O 2 The elements extracted are C, H, Br and O, and their numbers are 8, 8, 2 and 2 respectively.
[0020] Step 30, based on the element database, according to the elements and their number to be measured, respectively obtain the mass and abundance of the atomic group of each element to be measured.
[0021] Preferably, obtaining the mass and abundance of an atomic group of one of the elements α to be measured specifically includes: Search the element database and find that the element α to be tested has n isotopes, namely α 1 , α 2 , …, α n , the corresponding masses are Iso 1 , Iso 2 、…、Iso n , the abundances are x 1 、x 2 , …, x n ; n represents an integer greater than or equal to 1.
[0022] There are m isotopes of the element α in the test compound, and when n isotopes are combined, multiple different atomic groups will be obtained, each of which is composed of m elements. For example, the i-th atomic group of the element α In α 1 , α 2 , …, α n , , , , …, is an integer greater than or equal to 0 and less than or equal to m.
[0023] Use formula (1) to calculate the mass of each atomic group of the element α to be measured: Formula (1) In the formula, represents the mass of the i-th atomic group of the element α to be measured, represents the isotope α in the i-th atomic group of the element α to be measured 1 The number of represents the isotope α in the i-th atomic group of the element α to be measured 2 The number of represents the isotope α in the i-th atomic group of the element α to be measured n The number of ; m represents the number of elements α to be measured.
[0024] The abundance of each atomic group of the element α to be measured is calculated using the polynomial distribution formula shown in formula (2): Formula (2) In the formula, represents the abundance of the ith atomic group of the element α to be measured, represents the polynomial coefficients. Among them, Indicates m takes The number of combinations of express Pick The number of combinations of , …, express Pick The number of combinations.
[0025] Preferably, in step 30, the masses and abundances of all atomic groups of the element to be detected are obtained. Considering that atomic groups with abundances lower than 0.05% have no statistical significance, atomic groups with abundances lower than 0.05% are removed to increase the detection speed.
[0026] Step 40, combining the masses and abundances of the atomic groups of all the elements to be tested to obtain the masses and abundances of the molecular isotopes of the compound to be tested.
[0027] Specifically include: Combine the atomic groups of all the elements to be tested to obtain molecular isotopes. 8 H 8 Br 2 O 2 There are four elements to be tested: C, H, Br and O. The atomic groups of the four elements to be tested are combined respectively.
[0028] Add the mass numbers of all the atomic groups in each molecular isotope to obtain the mass of each molecular isotope.
[0029] Multiply the abundances of all atomic groups in each molecular isotope to obtain the abundance of each molecular isotope.
[0030] Preferably, in step 40, after obtaining the masses and abundances of all molecular isotopes of the test compound, molecular isotopes with abundances less than 0.01% are removed, considering that molecular isotopes with abundances less than 0.01% have almost no effect in practice.
[0031] Step 50, visualizing the mass and abundance of the molecular isotopes of the test compound to obtain a molecular isotope distribution map of the test compound.
[0032] Two specific examples and two comparative examples are provided below.
[0033] Example 1 (the compound to be tested is C 8 H 8 Br 2 O 2 ) After building the element database, compound C 8 H 8 Br 2 O 2 The four elements extracted are C, H, Br and O, and their numbers are 8, 8, 2 and 2 respectively.
[0034] The masses and abundances of the isotopes of the four elements to be tested, C, H, Br and O, were obtained by searching in the element database, as shown in Table 1.
[0035] Table 1 The mass and abundance of the isotopes of the four elements to be measured: C, H, Br and O
[0036] The mass of each atomic group of the four elements to be measured was calculated using formula (1), and the abundance of each atomic group of the four elements to be measured was calculated using formula (2). The atomic groups with abundance less than 0.0005 were removed. The results are shown in Table 2.
[0037] Table 2 Abundance of each atomic group of the four elements to be tested
[0038] The atomic groups of the four elements to be tested are combined separately, the masses of the atomic groups are added to obtain the masses of the molecular isotopes, and the abundances of the atomic groups are multiplied to obtain the abundances of the molecular isotopes, thus obtaining C 8 H 8 Br 2 O 2 The mass and abundance of molecular isotopes are shown in Table 3.
[0039] Table 3 C 8 H 8 Br 2 O 2 The mass and abundance of molecular isotopes
[0040] Example 2 (the compound to be tested is C 12 Br 10 ) The detection process is the same as in Example 1, and C 12 Br 10 The mass and abundance of molecular isotopes are shown in Table 4.
[0041] Table 4 C 12 Br 10 The mass and abundance of molecular isotopes
[0042] C 12 Br 10 The mass and abundance of the molecular isotopes are visualized to obtain the molecular isotope distribution diagram of the compound to be tested, such as Figure 2 shown. Figure 2 In the graph, the horizontal axis represents the mass of the molecular isotope and the vertical axis represents the abundance of the molecular isotope.
[0043] Comparative Example 1 (Compound to be tested is C 12 Br 10 ) The Isotope Distribution Calculator software from Agilent Technologies, USA, was used to test and the following results were obtained: Figure 3 The isotope distribution diagram shown. The Isotope Distribution Calculator software from Agilent Technologies, USA, is a software with a relatively high accuracy in calculating isotope distribution in this field.
[0044] Compare Table 4 and Figure 3It can be seen that the calculation accuracy of the method of the present invention is similar to that of the Agilent software. The mass and abundance obtained by the method of the present invention can be calculated to six decimal places, while the Agilent software can only calculate to four decimal places, and the calculation accuracy of the method of the present invention is higher. The calculation time of the method of the present invention is 0.1593 seconds, and the calculation time of the Agilent software is about 0.2 seconds. The calculation time of the method of the present invention is comparable to that of the commercial software.
[0045] Comparative Example 2 (Compound to be tested is C 12 Br 10 ) The open source software in the website GitHub was used for testing, and the following results were obtained: Figure 4 The isotopic distribution diagram is shown.
[0046] contrast Figure 2 and Figure 4 It can be seen that the calculation accuracy of the method of the present invention is higher. The calculation time of the method of the present invention is 0.1593 seconds, and the calculation time of the open source software in the website GitHub is 10.3865 seconds. The calculation time of the method of the present invention is shorter and more efficient.
[0047] The basic principles, main features and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above specific embodiments, and the descriptions in the above specific embodiments and the specification are only for further illustrating the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed for protection.
Claims
1. A method for detecting the isotope distribution of a compound, characterized in that: The following steps are involved: Step 10, constructing an element database; the element database includes the mass and abundance of isotopes of all elements in the periodic table; Step 20, extracting and obtaining the elements and their numbers according to the chemical formula of the compound to be tested; Step 30, based on the element database, according to the elements and their number to be measured, respectively obtain the mass and abundance of the atomic group of each element to be measured; Step 40, combining the masses and abundances of the atomic groups of all the elements to be tested to obtain the masses and abundances of the molecular isotopes of the compound to be tested.
2. The method for detecting compound isotope distribution according to claim 1, characterized in that: In step 30, obtaining the mass and abundance of the atomic group of the element α to be measured specifically includes: Search the element database and find that the element α to be tested has n isotopes, namely α 1 , α 2 , …, α n , the corresponding masses are Iso 1 , Iso 2 、…、Iso n , the abundances are x1, x2, …, x n ; n represents an integer greater than or equal to 1; Use formula (1) to calculate the mass of each atomic group of the element α to be measured: Formula (1) In the formula, represents the mass of the i-th atomic group of the element α to be measured, represents the isotope α in the i-th atomic group of the element α to be measured 1 The number of represents the isotope α in the i-th atomic group of the element α to be measured 2 The number of represents the isotope α in the i-th atomic group of the element α to be measured n The number of ; m represents the number of elements α to be measured.
3. The method for detecting compound isotope distribution according to claim 2, characterized in that: In step 30, the abundance of each atomic group of the element α to be measured is calculated using a polynomial distribution formula.
4. The method for detecting compound isotope distribution according to claim 3, characterized in that: The expression of the polynomial distribution formula is formula (2): Formula (2) In the formula, represents the abundance of the ith atomic group of the element α to be measured, Represents polynomial coefficients.
5. The method for detecting compound isotope distribution according to claim 1, characterized in that: The step 40 specifically includes: Combine all the atomic groups of the elements to be tested to obtain molecular isotopes; add up the masses of all the atomic groups in each molecular isotope to obtain the mass of each molecular isotope; multiply the abundances of all the atomic groups in each molecular isotope to obtain the abundance of each molecular isotope.
6. The method for detecting compound isotope distribution according to claim 1, characterized in that: In step 30, after the masses and abundances of all atomic groups of the element to be measured are obtained, atomic groups with abundances lower than 0.05% are removed.
7. The method for detecting compound isotope distribution according to claim 1, characterized in that: In step 40, after the masses and abundances of all molecular isotopes of the test compound are obtained, molecular isotopes with abundances lower than 0.01% are removed.
8. The method for detecting compound isotope distribution according to claim 1, characterized in that: Also includes: Step 50, visualizing the mass and abundance of the molecular isotopes of the test compound to obtain a molecular isotope distribution map of the test compound.