LC-MS-Based Peptide Quantitative Assays Service

Overview

Peptides play important roles in biological regulation, signaling processes, protein processing, and molecular interactions. Quantitative peptide analysis enables researchers to measure peptide abundance changes across different biological conditions, experimental groups, or treatment responses.

LC-MS/MS-based peptide quantitative assays provide molecular-specific measurement by detecting peptide signals according to their precursor and fragment ion information. This approach supports accurate peptide-level comparison, candidate validation, and investigation of dynamic changes in peptide expression. Depending on research objectives, peptide quantification workflows can be designed for targeted peptide measurement, global peptide abundance analysis, or modified peptide quantification.

LC-MS-Based Peptide Quantitative Assays Service at MtoZ Biolabs

MtoZ Biolabs provides LC-MS/MS-based peptide quantitative assays integrating optimized sample preparation, mass spectrometry analysis, quantitative data processing, and bioinformatics interpretation.

According to sample characteristics, experimental design, and analytical objectives, appropriate quantitative strategies are selected to achieve reliable peptide measurement.

The service includes:

1. Targeted Peptide Quantification

Targeted peptide quantification focuses on predefined peptide targets using targeted LC-MS/MS approaches such as PRM, MRM, or SRM.

By monitoring specific precursor and fragment ion signals, this strategy enables sensitive and reproducible measurement of selected peptides. It is suitable for candidate peptide validation, quantitative comparison, and monitoring peptide changes across experimental conditions.

2. Global Peptide Quantification

Global peptide quantification enables systematic measurement of peptide abundance across complex biological samples.

Depending on study requirements, different quantitative strategies can be applied, including:

• Label-Free Quantification (LFQ) for large-scale peptide abundance comparison without labeling; 
• Stable isotope-based quantification, including metabolic labeling approaches such as SILAC and isobaric labeling strategies such as TMT/iTRAQ, for quantitative comparison across experimental groups. 

These approaches support comparative analysis of peptide expression patterns under different biological conditions.

3. Modified Peptide Quantification

Modified peptides often require specialized analytical strategies due to their modification-specific characteristics and potential enrichment requirements.

By combining enrichment approaches with LC-MS/MS analysis, MtoZ Biolabs supports quantitative analysis of modified peptide forms, including:

• phosphorylated peptides; 
• acetylated peptides; 
• other post-translationally modified peptides. 

Quantitative strategies are selected according to modification type, sample characteristics, and research objectives.

Analysis Workflow

1. Experimental Design and Quantitative Strategy Selection

Sample type, experimental design, peptide analysis objectives, and quantitative requirements are evaluated to determine an appropriate workflow.

2. Sample Preparation and Peptide Extraction

Samples are processed using optimized preparation workflows to generate peptide solutions compatible with LC-MS/MS analysis.

For modified peptide studies, enrichment strategies can be incorporated according to modification characteristics and project requirements.

3. LC-MS/MS Data Acquisition

Peptide samples are analyzed using optimized LC-MS/MS workflows selected according to sample complexity and quantitative objectives.

4. Quantitative Data Processing

Mass spectrometry data are processed for peptide identification, quantitative signal extraction, normalization, and comparison between experimental groups.

5. Bioinformatics Analysis

Quantitative peptide datasets can be further analyzed through statistical comparison, clustering, annotation, and functional interpretation according to project requirements.

Applications

1. Biomarker Candidate Research

Quantify candidate peptides identified from discovery studies to evaluate abundance differences across biological samples or experimental groups.

2. Drug Response and Biological Perturbation Studies

Analyze peptide abundance changes following drug treatment, stimulation, genetic modification, or other experimental interventions.

3. Protein Regulation and Functional Studies

Investigate peptide-level changes associated with protein regulation, signaling processes, and biological responses.

4. Post-Translational Modification Studies

Quantify modified peptides to study dynamic regulation of phosphorylation, acetylation, and other modification events.

5. Comparative Biological Research

Compare peptide expression patterns across tissues, cell models, organisms, developmental stages, or different experimental conditions.

What Could be Included in the Report?

1. Experimental Details

Sample information, experimental design, peptide analysis strategy, and workflow information.

2. Materials, Instruments, and Methods

Sample preparation, LC-MS/MS methods, and data acquisition parameters.

3. Quality Assessment

Mass spectrometry performance, peptide identification quality, and quantitative evaluation.

4. Quantitative Results

Peptide identification results, abundance tables, and comparative analysis.

5. Bioinformatics Analysis

Statistical analysis, clustering, annotation, and functional interpretation according to project requirements.

6. Raw Data Files

Raw MS files and processed quantitative datasets.

Why Choose MtoZ Biolabs?

1. High Sensitivity Detection

Enables precise quantification and dynamic monitoring of low-abundance peptides.

2. High-Resolution Analysis

Ensures effective separation and accurate quantification of peptide signals in complex samples.

3. Multiple Quantification Strategies

Supports various modes, including label-free, isotope-labeled, and targeted quantification.

4. Strong Data Reliability

Standardized workflows guarantee reproducibility and comparability of results.

5. Comprehensive Technical Support

Covers the entire process from sample preparation to mass spectrometry detection and data interpretation.

FAQ

Q1. What types of samples are suitable?

The LC-MS-based peptide quantitative assays service is suitable for various peptide samples, including synthetic peptides, recombinant peptides, and biological extracts. To ensure analytical accuracy, it is recommended that samples have high purity and are free from salts, buffers, or other contaminants.

Q2. How should I prepare my samples?

To ensure analytical quality and reproducibility, please follow these guidelines:

(1) Purity requirements: Avoid high salt, buffer residues, and other contaminants.

(2) Storage conditions: Store at -20℃ for short term, or -80℃ for long term.

(3) Transportation: Ship with cold chain or dry ice, ensuring proper sealing, leak prevention, and clear sample labeling.

For more information, please refer to Sample Submission Guidelines for Proteomics, Sample Submission Guidelines for Metabolomics.

Q3. What is the service general workflow?

Q4. What quantitative strategies can be used for peptide analysis?

Depending on research objectives, peptide quantification can be performed using targeted approaches, label-free quantification (LFQ), stable isotope-based quantification, TMT/iTRAQ-based multiplexed quantification, SILAC, or absolute quantification workflows using isotope-labeled internal standards.

Contact Us

Different research objectives require different peptide quantification strategies, from targeted measurement of selected peptides to comprehensive peptide abundance analysis and modified peptide characterization.

Share your sample information and research objectives with MtoZ Biolabs. Our team can help evaluate the suitable LC-MS/MS-based peptide quantitative workflow for your project.