Detailed explanation of LC-MS molecular weight determination technology

Detailed explanation of LC-MS molecular weight determination technologyIntroduction to Testing Technology Services Details

Accurate determination of molecular weight is a fundamental step in multiple aspects such as structural identification, quality control, and drug development in life science research and biopharmaceutical development. Whether it is confirming the complete expression of proteins or verifying the purity of synthesized small molecules, molecular weight information is one of the data of b ù k ě hu ò qu ē. Among numerous molecular weight determination techniques, liquid chromatography-mass spectrometry (LC-MS) is widely used for molecular weight determination of d à nb á izh ì, peptide segments, small molecule drugs, and even metabolites due to its high sensitivity, wide applicability, and structural analysis ability.

1、 Overview of LC-MS Technology Principles

LC-MS is a combined system of liquid chromatography (LC) and mass spectrometry (MS) techniques

• LC section: Firstly, different components in the sample are separated by chromatography to reduce matrix interference and improve detection specificity.

• MS part: Then, the ion mass to charge ratio (m/z) is detected by ionization and mass analyzer to obtain the molecular weight information of each component.

Common ionization methods include:

• ESI (electric spray ionization): suitable for analyzing polar compounds, such as d à nb á izh ì, polypeptides, nucleotides, etc.

• APCI (Atmospheric Pressure Chemical Ionization): Suitable for volatile small molecules.

• MALDI (Matrix Assisted Laser Desorption Ionization): commonly used for rapid molecular weight scanning of d à nb á izh ì.

In Biotech, we mainly use high resolution electrospray mass spectrometry (HR-ESI-MS) with optimized chromatographic system to measure the molecular weight of small molecules to high molecular biological products.

2、 The advantages of LC-MS in molecular weight determination

1. Coexistence of high sensitivity and high accuracy

LC-MS systems can detect target substances at concentrations as low as picomoles (pmol) or lower, with mass errors typically controlled within<5 ppm, making them particularly suitable for molecular weight analysis of trace components in complex samples.

2. Compatibility with complex samples

Compared to traditional methods such as SDS-PAGE or UV absorption, LC-MS is almost unaffected by sample impurities and can be directly used in complex systems such as cell lysate, serum, and fermentation supernatant.

3. Can provide structural related information

In addition to molecular weight, MS can also provide structural clues such as isotope distribution, fragment information, and post-translational modifications (such as phosphorylation and glycosylation), which have natural advantages in confirming molecular structures.

3、 Typical application scenarios for LC-MS molecular weight determination

1. D à nb á izh ì molecular weight verification

In the process of recombinant protein expression and purification, confirming the integrity of the target protein (such as whether there is N-terminal truncation, C-terminal deletion, or signal peptide uncut) is a routine QC step. The molecular weight of j ī ngqu è measured by LC-MS can quickly determine whether the protein matches the theoretical molecular weight and identify the presence of minor modifications.

2. Purity and identity confirmation of small molecule drugs

LC-MS is one of the methods for confirming the structure of drug molecules after synthesis. By obtaining plasma peaks of [M+H]+and [M+Na]+, it is determined whether the molecular weight of the main peak is consistent with the target structure, and the presence of synthetic by-products or degradation products is monitored.

3. Quality control of peptide synthesis

Artificially synthesized peptides are prone to chain end elongation failure or residue deletion. LC-MS can efficiently determine the integrity of peptide sequences, improve the success rate of synthesis, and enhance the reliability of subsequent experiments.

4. Molecular labeling of metabolomics and lipidomics

In metabolomics, LC-MS is not only used for quantification, but also for molecular weight screening of characteristic metabolites or differential substances, providing a basis for subsequent structural analysis (such as MS/MS).

4、 Comparison with other molecular weight measurement techniques

Conclusion: Each method has its own application scenarios, and LC-MS is gradually becoming the mainstream molecular weight determination scheme in modern biological analysis due to its accuracy, applicability, and structural analysis capabilities.

5、 Advantages of LC-MS molecular weight determination service provided by Baitai Paike Biotechnology

At Baitai Paike Biotechnology, we have built an LC-MS analysis system based on g ā odu ā n platforms such as Thermo Orbitrap and Bruker QTOF, and equipped it with dedicated sample preprocessing and data analysis processes. It has the following core advantages:

• One stop detection capability from small molecules to d à nb á izh ì.

• Delivery within 3-5 working days, compatible with multiple sample types.

• Support extended services such as post translation modification analysis and isomer recognition.

• Provide raw data and Zhu ā ny è reports for project archiving and publication.

With the deepening of biological research and the acceleration of drug development, the accuracy and information depth of molecular weight determination are increasingly valued. LC-MS is helping scientists move from "having" to "accuracy" and from "quantity" to "quality" with its analytical capabilities. If you are conducting d à nb á izh ì identification, small molecule validation, or peptide quality control, please feel free to contact Baitai Paike Biotechnology. We will provide strong data support for your research project using Zhu ā ny è's LC-MS technology platform.

~~

Baitai Paike Biotechnology Characteristic Project

1、 Protein sequencing

Biotec Biotech uses Thermo's newly launched Obitrap Fusion Lumos mass spectrometer and Shimadzu's Edman degradation sequencing system to analyze the d à nb á izh ì sequence, providing mass spectrometry based protein sequencing analysis services, including amino acid composition analysis of d à nb á izh ì, Ndu ā nc è x ù, Cdu ā nc è x ù, and full sequence analysis, as well as d à nb á izh ì N-terminal sequence analysis services based on Edman degradation. For unknown theoretical sequences, we provide de novo sequencing services based on de novo sequencing to analyze protein sequences.

※ Service advantages:

1. Adopting the world's advanced mass spectrometer Obitrap Fusion Lumos;

2. It can achieve 100% coverage of the measured target protein sequence;

3. It can determine up to 70 amino acid sequences at the N-terminus of proteins;

4. Can measure various forms of samples: protein solution, PVDF protein bands;

5. Low sample usage: Protein samples only require 5-10ug to complete detection;

6. Sequencing is not affected by N-terminal modifications such as blocking, PEC, and glycosylation.

2、 D à nb á izh ì omics

Biotec Biotech uses Thermo Fisher's Orbitrap Fusion Lumos mass spectrometry platform combined with Nano LC to provide a variety of d à nb á izh ì omics analysis services, including quantitative d à nb á izh ì omics, targeted d à nb á izh ì omics, proteomics, post-translational modified proteomics, and more. In addition, Baitai Paike Biotechnology has launched a 4DD à nb á izh ì omics service based on timsTOF Pro, which helps with research in micro sample proteomics, large sample population medicine, and high-throughput modification genomics.

※ Service advantages:

1 . High throughput quantitative protein analysis: Large scale experimental analysis with multiple control groups, discovering new biomarkers;

2. Multiple in vitro and in vivo labeling methods are suitable for analyzing various samples such as tissues, cells, and blood;

3. High sensitivity of mass spectrometry analysis and high repeatability of experimental results;

4. Can detect low abundance proteins with a wide linear range;

5. Bioinformatics analysis is more systematic and accurate.

3、 Single cell mass spectrometry flow cytometry analysis

Baitai Paike Biotechnology uses the Fluidigm mass spectrometry flow cytometry system for single-cell mass spectrometry analysis. Metal element markers (usually metal element labeled specific antibodies) are used to label molecules on the surface and inside of cells. Then, individual cells are separated using flow cytometry principles, and the atomic mass spectrum of individual cells is analyzed using inductively coupled plasma mass spectrometry (ICP-MS). The atomic mass spectrum data is then converted into signal molecule expression levels on the cell surface and inside.

※ Service advantages:

1. Advanced technology, filling technological gaps

The use of metal labeled antibody technology avoids the problem of few and easily interacting channels in traditional flow cytometry fluorescence. At the single-cell level, multiple indicators can be characterized simultaneously, and Baitai Paike Biotechnology can detect 51 target proteins simultaneously.

2. Large analysis quantity and low cost

Single cell RNAseq is limited by factors such as cost, and the total number of analyzed cells for all samples is generally around 2x10 ^ 4. However, flow cytometry technology can analyze at least 10 ^ 5 cells in one sample, achieving an order of magnitude increase, and the cost is not higher than that of single-cell RNAseq.

3. Great application prospects

① The results of flow cytometry can provide changes in cell subpopulations, which have great research prospects in clinical diagnosis, disease mechanism research, and other fields;

② Combining metal tag technology with other technologies will lead to new application directions. In addition to conventional proteins, mass spectrometry flow cytometry technology can also be used for post-translational modification of proteins;

③ Can detect cell survival rate, cell size, mRNA transcript expression level, DNA synthesis rate, and protease activity.

4、 Immunopeptide omics analysis and novel antigen discovery based on high-precision mass spectrometry

The one-stop solution for high-precision mass spectrometry based immunopeptidomic analysis and new antigen discovery from Biotec Biotech includes our proprietary, highly sensitive immunopeptide enrichment and identification scheme. We can assist you in identifying and recognizing over 10000 type I peptides and over 10000 type II peptides. Through our optimized high-throughput immunopeptidomic analysis platform, immunopeptidomic analysis can be performed with reproducible identification and quantification from small sample materials. This service can be applied to large-scale research, aiming to assist researchers in finding solutions for cancer, immune diseases, and infectious diseases, and to explore unknown targets in depth.

5、 Characterization of Biopharmaceuticals

Baitai Parker is based on high-resolution mass spectrometry technology, MALDI TOF， High performance chromatography separation technology provides a range of biological drug analysis solutions, from amino acid composition and primary structure analysis of biological products such as d à nb á izh ì, peptides, antibodies, vaccines, to product variability and purity analysis. Intended to provide high-quality biopharmaceutical analysis services and assist biopharmaceutical manufacturers in improving the quality of biopharmaceuticals.

Baitai Paike Biotechnology's Seven Major Testing Platforms

Baitai Paike Biotechnology - High quality service provider for characterization of biological products and multi omics of biological mass spectrometry

Beijing Baitai Paike Biotechnology Co., Ltd. is committed to providing quality control testing and project validation services for the biological/pharmaceutical and medical device industries. The company's laboratory follows regulations and guidelines such as NMPA, ICH, FDA, and EMA, and has obtained CNAS/ISO9001 dual quality system certification. It has established a complete quality system, including data cold and hot/remote backup, regular equipment measurement/periodic verification, software audit tracking, and provides customers with integrated solutions and technical services to support new drug research and development, drug application registration, and production release.

1. The company adopts the ISO9001 quality control system and provides CRO detection and analysis services based on mass spectrometry;

2. Recognized by the National CNAS Laboratory, we provide customers with drug quality research services that comply with global pharmaceutical regulations;

3. The business scope covers omics, proteomics, metabolomics, biopharmaceutical characterization, single-cell analysis, single-cell mass spectrometry flow cytometry, bioinformatics cloud analysis, and multi omics integrated analysis of biological mass spectrometry;

4. Seven major quality control testing platforms to meet your one-stop service needs;

5. Providing services to over 3000 enterprises and 10000+customers;

6. Committed to providing you with high-quality biological mass spectrometry analysis services!

Detailed explanation of LC-MS molecular weight determination technologyIntroduction to Testing Technology Services Details