CN-121986263-A - Assignment of glycan peaks

Abstract

In some examples, an apparatus may include a Retention Time (RT) receiver executed by at least one hardware processor to receive a glucose ladder standard Retention Time (RT) and to receive neutral and charged glycans RT. An RT analyzer executed by the at least one hardware processor may determine an adjusted Glucose Unit (GU) value based on applying the glucose ladder standard RT and the neutral and charged glycans RT to expected GU values. Further, an expected RT generator executed by the at least one hardware processor may determine an expected RT for a given glycan based on the adjusted GU values.

Inventors

• E. Lister
• O. Potter
• R. ROBINSON

Assignees

• 安捷伦科技有限公司

Dates

Publication Date

20260505

Application Date

20240815

Priority Date

20240430

Claims (20)

1. 1. A glycan peak assignment apparatus, comprising: a Retention Time (RT) receiver, the retention time receiver being executed by at least one hardware processor to: the received glucose step sample Retention Time (RT), and Receiving neutral and charged glycans RT; an RT analyzer, the RT analyzer being executed by the at least one hardware processor to: Determining an adjusted Glucose Unit (GU) value based on applying the glucose ladder standard RT, and the neutral and charged glycans RT to an expected GU value; An expected RT generator, the expected RT generator executed by the at least one hardware processor to: determining an expected RT for the specified glycans based on the adjusted GU values, and A compound identifier, the compound identifier being executed by the at least one hardware processor to: identifying at least one compound based on the expected RT.
2. 2. The glycan peak attribution device according to claim 1, wherein the RT analyzer is executed by the at least one hardware processor to determine the adjusted GU value based on applying the glucose ladder standard RT, and the neutral and charged glycans RT, to the expected GU value by: Based on the glucose ladder standard RT, a fifth order polynomial GU is determined as a function of RT.
3. 3. The glycan peak attribution device according to claim 2, wherein the RT analyzer is executed by the at least one hardware processor to determine the adjusted GU value based on applying the glucose ladder standard RT, and the neutral and charged glycans RT, to the expected GU value by: The observed GU is determined based on the fifth order polynomial GU and the neutral and charged glycans RT.
4. 4. A glycan peak attribution device according to claim 3, wherein the RT analyzer is executed by the at least one hardware processor to determine the adjusted GU value based on applying the glucose ladder standard RT, and the neutral and charged glycans RT, to the expected GU value by: determining GU adjustment factors based on the observed GUs, and The adjusted GU value is determined based on applying the GU adjustment factor to the expected GU value.
5. 5. The glycan peak homing device of claim 4, wherein the GU adjustment factor comprises a first value representing a neutral glycan adjustment value.
6. 6. The glycan peak assignment device of claim 4, wherein the GU adjustment factor comprises a second value representing an acidic glycan adjustment value applied to S2 glycans.
7. 7. The glycan peak assignment device of claim 4, wherein the GU adjustment factor includes a third value representing an acidic glycan adjustment value multiplied by a factor of 0.5 and applied to S1 glycans.
8. 8. The glycan peak assignment device of claim 4, wherein the GU adjustment factor comprises a fourth value representing an acidic glycan adjustment value multiplied by a factor of 1.5 and applied to S3 glycans.
9. 9. The glycan peak assignment device of claim 4, wherein the GU adjustment factor includes a fifth value representing an acidic glycan adjustment value multiplied by a factor of 2.0 and applied to S4 glycans.
10. 10. The glycan peak attribution device according to claim 4, wherein the RT analyzer is executed by the at least one hardware processor to determine the adjusted GU value based on applying the glucose ladder standard RT, and the neutral and charged glycans RT, to the expected GU value by: the adjusted GU values are determined based on subtracting the GU adjustment factors from the corresponding expected GU values.
11. 11. The glycan peak attribution device according to claim 1, wherein the RT analyzer is executed by the at least one hardware processor to determine the adjusted GU value based on applying the glucose ladder standard RT, and the neutral and charged glycans RT, to the expected GU value by: based on the glucose ladder standard GU, a fifth order polynomial RT is determined as a function of RT.
12. 12. A method for glycan peak assignment, the method comprising: Receiving, by at least one hardware processor, at least one glucose step standard Retention Time (RT) and at least one neutral and charged glycan RT; determining, by the at least one hardware processor, at least one glucose step standard RT, and the at least one neutral and charged glycan RT based on applying the at least one GU adjustment factor to at least one expected Glucose Unit (GU) value, and Determining, by the at least one hardware processor, at least one adjusted GU value based on the at least one GU adjustment factor, and At least one expected RT for at least one designated glycan is determined by the at least one hardware processor based on the at least one adjusted GU value.
13. 13. The method of claim 12, wherein determining, by the at least one hardware processor, the at least one adjusted GU value based on the at least one GU adjustment factor further comprises: the at least one adjusted GU value is determined based on subtracting the at least one GU adjustment factor from at least one expected GU value.
14. 14. A non-transitory computer-readable medium having stored thereon machine-readable instructions that, when executed by at least one hardware processor, cause the at least one hardware processor to: determining an adjusted glucose step standard Retention Time (RT) and neutral and charged glycans RT applied to expected Glucose Unit (GU) values; based on the adjusted GU values, an expected RT for the specified glycans is determined.
15. 15. The non-transitory computer-readable medium of claim 14, wherein the machine-readable instructions to determine the adjusted GU value based on applying the glucose ladder standard RT and the neutral and charged glycans RT to expected GU values, when executed by the at least one hardware processor, further cause the at least one hardware processor to: A fifth order polynomial GU as a function of RT is determined based on the glucose ladder standard RT.
16. 16. The non-transitory computer-readable medium of claim 15, wherein the machine-readable instructions to determine the adjusted GU value based on applying the glucose ladder standard RT and the neutral and charged glycans RT to expected GU values, when executed by the at least one hardware processor, further cause the at least one hardware processor to: The observed GU is determined based on the fifth order polynomial GU and the neutral and charged glycans RT.
17. 17. The non-transitory computer-readable medium of claim 16, wherein the machine-readable instructions to determine the adjusted GU value based on applying the glucose ladder standard RT and the neutral and charged glycans RT to expected GU values, when executed by the at least one hardware processor, further cause the at least one hardware processor to: determining GU adjustment factors based on the observed GUs, and The adjusted GU value is determined based on applying the GU adjustment factor to the expected GU value.
18. 18. The non-transitory computer-readable medium of claim 17, wherein the GU adjustment factor comprises: A first value representing a neutral glycan adjustment value; a second value representing an acidic glycan adjustment value applied to the S2 glycan; a third value representing an acidic glycan adjustment value multiplied by a factor of 0.5 and applied to the S1 glycan; A fourth value representing an acidic glycan adjustment value multiplied by a factor of 1.5 and applied to the S3 glycan, and A fifth value representing an acidic glycan adjustment value multiplied by a factor of 2.0 and applied to S4 glycans.
19. 19. The non-transitory computer-readable medium of claim 17, wherein the machine-readable instructions to determine the adjusted GU value based on applying the glucose ladder standard RT and the neutral and charged glycans RT to expected GU values, when executed by the at least one hardware processor, further cause the at least one hardware processor to: the adjusted GU values are determined based on subtracting the GU adjustment factors from the corresponding expected GU values.
20. 20. The non-transitory computer-readable medium of claim 14, wherein the machine-readable instructions, when executed by the at least one hardware processor, further cause the at least one hardware processor to: generating a library of expected RT's based on the expected RT's for the specified glycans, and Signals observed in Liquid Chromatography (LC)/Mass Spectrometry (MS) data are assigned to glycan structures based on the expected RT from the library of expected RTs.

Description

Assignment of glycan peaks Cross Reference to Related Applications The present application claims priority from co-pending U.S. provisional patent application serial No. 63/587,593 entitled "GLYCAN PEAK ASSIGNMENT (glycan peak assignment)" filed on month 10, 2023 and U.S. non-provisional patent application serial No. 18/650,999 entitled "GLYCAN PEAK ASSIGNMENT (glycan peak assignment)" filed on month 4, 2024, the disclosures of which are incorporated herein by reference in their entireties. Background With respect to glycans, releasing glycans from glycoproteins and labeling the glycans with fluorescent labels facilitates relative quantification of each different glycan structure in a sample. In one example, liquid Chromatography (LC) may be used to separate the labeled released glycans. Drawings The features of the present disclosure are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings in which like reference numerals refer to similar elements and in which: FIG. 1 illustrates a layout of a glycan peak assignment device according to an example of the present disclosure; FIG. 2 illustrates a flow chart showing the utilization of the operation of the glycan peak assignment device of FIG. 1 and determining an observed Glucose Unit (GU), an expected GU, and a predicted GU according to an example of the present disclosure; FIG. 3 illustrates a flow chart of a scaling process to demonstrate operation of the glycan peak attribution device of FIG. 1, according to an example of the present disclosure; FIG. 4 illustrates a flow chart and associated examples of generating a hypothetical Retention Time (RT) for a degree of polymerization (d.p.s) beyond those observed experimentally by fitting to a function to demonstrate the operation of the glycan peak attribution device of FIG. 1, according to examples of the present disclosure; FIG. 5 illustrates an improvement in RT prediction accuracy in implementing adjustment values to demonstrate operation of the glycan peak assignment device of FIG. 1 according to an example of the present disclosure; FIG. 6 illustrates an example block diagram for glycan peak assignment according to examples of this disclosure; FIG. 7 illustrates a flow chart of an example method for glycan peak assignment in accordance with an example of the present disclosure, and Fig. 8 illustrates another example block diagram for glycan peak assignment according to another example of this disclosure. Detailed Description For simplicity and illustration, the present disclosure is described primarily by reference to examples. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. It may be evident, however, that the practice of the present disclosure is not limited to these specific details. In other instances, some methods and structures have not been described in detail to avoid unnecessarily obscuring the present disclosure. Throughout this disclosure, the terms "a" and "an" are intended to mean at least one of the specified elements. As used herein, the term "include" means including but not limited to, and the term "including" means including but not limited to. The term "based on" means based at least in part on. Disclosed herein are glycan peak attribution apparatuses, methods for glycan peak attribution, and non-transitory computer-readable media having machine-readable instructions stored thereon for providing glycan peak attribution. Regarding the release of glycans from glycoproteins and labeling of the glycans with fluorescent labels, attributing peaks to glycan structures can be technically challenging. In some cases, the Retention Time (RT) of the peak may be used to determine the identity (identity) of the glycan structure. However, utilizing retention times may include the disadvantage that retention times may vary significantly due to different dates, life of the columns, poorly controlled parameters such as ambient temperature effects, minor variations in the composition of the Liquid Chromatography (LC) mobile phase, and/or differences between individual columns of the same type. The selectivity (α) between different oligosaccharides may be relatively stable for the separation mode associated with hydrophilic interaction chromatography (hiclc) compared to the relatively unstable absolute RT of the different oligosaccharides. In this regard, carbohydrate standards may be used to normalize retention times, thereby creating a Retention Index (RI) that may be used to control the above-described variations. RI for glycan structures can be more stable than retention time and thus can be more suitable for attributing peaks to structures. In one example, peaks can be assigned to glycan structures by reference to a library of expected RIs formed based on the results of separation experiments of previously encountered glycans with well-validated structures.