Protein characterization

During the purification process, routine SDS-PAGE and western blot will be carried out to assess the target protein as a part of our quality assurance. Upon the completion of the purification, our quality control specialists will assess the final product in pursuant to your requirement.

Case study 1 - Characterization and Bioactivity Test of Cytokine

  • Workflow:

    • The target cytokine gene was synthesized and subcloned into pET30a vector.
    • Plasmid was transformed into high-efficiency BL-21 E. coli cell.
    • High expression E. coli strain was selected by antibiotics
    • Large-scale culture to express target cytokine.
    • The cytokine was purified by IEX and SEC resin.
  • Deliverables:

    Bioactive cytokine

  • 1. Production of Cytokine in E. coli System

  • Fig. 1 SDS-PAGE analysis of cytokine after purification
    A: Purified cytokine (non-reduced)
    B: Purified cytokine (reduced)
    MK: Molecular weight standards
  • 2. Characterization of cytokine product

    Fig. 2 Characterization of cytokine product by mass spectrum
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    Sequencing verification by MS/MS assay
  • 3. Bioactivity Assay of final cytokine product

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    Fig.3 Bioactivity assay showing Novoprotein cytokine with similar bioactivity as commercial product in market.

Case study 2 – Endotoxin level control

Endotoxin level (Eu/mg) Protein concentration(ug/ml) Protein concentration(ug/ml) Dilution times LAL result (positive+, negative -)
10000.51000-
10000.51000-
5001500-
5001500-
1005100-
1005100-
105050-
105050-
52510-
52510-
LAL(Limulusamebocytelysate) controlled to 5EU/mg

We also offer post-purification services including isotope labeling, process development, protein crystallization, peptide synthesis, and mammalian stable cell line generation. For information about our protein expression and purification services, please visit our protein expression and purification page or contact us at sales@novoprotein.com. Want to know how other scientists speak of us? Check out our References.

YOUR CONCERNS

Will I get what I am promised?
Our counter-contract ensures your terms of expectation are met.

I feel like losing control of data generation!
Our service team keeps tight monitoring and tracking over each step where data are generated.