SEC-HPLC Based Molecular Weight Identification Service

MtoZ Biolabs provides SEC-HPLC Based Molecular Weight Identification Services to determine the apparent molecular weight and size distribution of proteins and protein assemblies under native solution conditions. By profiling monomers, oligomers, and aggregates with high-resolution size-exclusion chromatography, this service delivers clear, reproducible evidence to support biopharmaceutical development, quality control, and protein characterization studies.

Overview

Molecular weight is a primary descriptor of a protein sample. SEC-HPLC is widely used for molecular weight identification because it separates molecules by hydrodynamic size without relying on binding or harsh chemical conditions. The resulting elution profile provides an interpretable view of sample heterogeneity, enabling estimation of apparent molecular weight, assessment of homogeneity, and comparison across lots, conditions, or timepoints.

Principle of SEC-HPLC Based Molecular Weight Identification

Size-exclusion chromatography separates molecules based on how they partition into porous particles packed inside the column.

🔸Larger species are excluded from more pores, travel a shorter path, and elute earlier.

🔸Smaller species access more pore volume, travel a longer path, and elute later.

🔸Retention time or elution volume is compared against a calibration curve generated using molecular weight standards.

🔸The result is an apparent molecular weight estimate that reflects hydrodynamic size in solution rather than exact mass.

Because SEC reports size behavior, interpretation considers shape, compactness, and interactions with the column matrix. A well-designed method minimizes non-size effects and supports consistent, decision-ready comparisons.



Ludwig N. et al. Curr Protoc Immunol. 2019.

Figure 1. Illustration of the SEC principle

SEC-HPLC Based Molecular Weight Identification Service at MtoZ Biolabs

SEC-HPLC Based Molecular Weight Identification Service at MtoZ Biolabs provides a practical way to assess protein size in solution and verify sample heterogeneity. Using size-exclusion high-performance liquid chromatography, MtoZ Biolabs estimates apparent molecular weight based on calibrated elution behavior and reports the distribution of major species such as monomers, oligomers, and higher-molecular-weight aggregates. The workflow is designed for clear comparisons across lots, constructs, formulations, and stress conditions, with results delivered in an interpretation-ready format for development, QC, and research decisions.

Why Choose MtoZ Biolabs

☑️Customizable Study Setup

Column selection, method conditions, and reporting endpoints are tailored to your protein and molecular weight range.

☑️Advanced Chromatography Platform

High-performance SEC-HPLC systems support stable retention, sharp peak shapes, and reliable size separation.

☑️Strict Quality Control

System suitability and run controls are used to keep results consistent across batches and study days.

☑️Responsive Customer Support

Clear sample guidance and timely communication help projects stay efficient from intake to final report.

Applications of SEC-HPLC Based Molecular Weight Identification Service

1. Biopharmaceutical Development

SEC-HPLC confirms the apparent molecular weight of the main species and tracks monomer to oligomer or aggregate distributions for developability decisions.

2. Quality Control and Lot Comparability

Molecular weight profiles from SEC-HPLC support batch-to-batch consistency checks by comparing retention behavior and size-population ratios.

3. Formulation and Stability Studies

Shifts in apparent molecular weight and peak distribution reveal size changes driven by pH, excipients, temperature, agitation, or freeze-thaw.

4. Protein Purification Assessment

SEC-HPLC molecular weight readouts show whether purification steps enrich the intended size species and reduce undesired higher-molecular-weight forms.

5. Process Troubleshooting

When unexpected size variants appear, SEC-HPLC highlights where molecular weight distributions change across conditions or processing stages.

FAQ

Q1: What types of samples are suitable?

1. Purified proteins and protein complexes, including recombinant proteins and fusion proteins

2. Biologics such as monoclonal antibodies, Fc-fusions, and antibody fragments

3. Protein formulations and process intermediates from development or manufacturing workflows

If you have special or limited material, we can assess feasibility and optimize a suitable workflow.

Q2: How should I prepare my samples?

1. Provide your research objective and basic sample information such as molecule type, expected molecular weight range, and buffer or formulation

2. Clarify samples by brief centrifugation or filtration when appropriate to remove particulates

3. Avoid repeated freeze-thaw cycles, aliquot if needed, store at 2 to 8°C or -80°C depending on sample stability, and ship with temperature control

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

Q3: What is the service general workflow?



Q4: What data formats are provided?

1. Instrument raw data files

2. Processed tables: Apparent molecular weight estimates, retention time or elution volume, and peak area percentages in XLSX or CSV.

3. Figures: Annotated SEC chromatograms and summary plots in PNG or TIFF.

4. Report: A PDF report summarizing methods, column and mobile phase conditions, key parameters, QC notes, results summary, and interpretation notes.

Additional formats can be provided upon request to meet specific analysis or publication requirements.

Start Your Project with MtoZ Biolabs

Contact us to discuss your experimental design or request a quote. Our technical specialists are available to provide a free business assessment.