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Gene Therapy Vector Purity Evaluation Service

Evaluation of Viral Vector Purity

Research products based on gene therapy viral vectors are currently facing clinical development challenges. Our company is committed to developing sensitive and ready-to-use methods to help customers detect and quantify potentially harmful contaminants left behind by viral vector production workflows. Our reliable and accurate impurity detection solutions will contribute to the development of gene therapy products for rare diseases.


Viral vectors expressing therapeutic genes show great promise for the treatment of a wide range of diseases, particularly rare diseases, and represent an emerging new therapeutic paradigm. One of the challenges in making progress in the development of current viral vector-based investigational products is the identification and characterization of the product- and process-related impurities present in even highly purified formulations.

During the production of viral vectors for gene delivery, impurities are often derived from the host cell system where the vector product is produced or from downstream purification processes. It is necessary to develop sensitive methods to measure host cell protein (HCP), host cell DNA (HC DNA), and common pollutants, which is crucial to identify the impurities in the vector prepared for the development of human rare disease treatment products, and helps to ensure and control the purity, efficacy, and safety of products.

Fig. 1 Adeno-associated virus (AAV) vector and impurity levels during purification.

Fig. 1 Adeno-associated virus (AAV) vector and impurity levels during purification. (Wright J F, 2014)

Viral Vector Purity Detection Services

In order to establish a good understanding of potential residues early in the process development, we offer our customers sensitive, accurate and precise impurity detection to assess the purity of viral vectors through technologies such as droplet digital PCR (ddPCR). Our services include, but are not limited to:

  • Analysis of host cell-related impurities
    The analysis and removal of host cell impurities are important for the production of gene therapy products as certain host cell molecules may act as adjuvants to stimulate anti-vector immune responses. We offer our customers a variety of analytical techniques such as the quantification of host cell nucleic acids by real-time or quantitative PCR (qPCR) or the detection of host cell impurities using transmission electron microscopy (TEM).
    • Detection of HEK293 residual DNA
      • Many gene therapy viral vectors are manufactured in HEK293 cells, therefore we offer ddPCR assays to accurately and precisely quantify residual HEK293 DNA in gene therapy drugs, which is essential for the production of safe therapeutics.
    • Detection of HEK293 residual DNA size
      • We offer customers HEK293-specific ddPCR-based residual DNA sizing solutions to measure HEK293 size and verify that any HEK293 residual DNA in a gene therapy formulation is below the FDA-recommended size of 200 base pairs.
  • Analysis of process impurities
    We provide our customers with the identification of process impurities in the preparation of viral vectors, usually by MS and chromatography.

Our Advantages

  • Sensitive and precise impurity testing for gene therapy
  • Move quickly with an easy protocol
  • Reasonable cost and customized development schedule

With extensive expertise and years of service in the gene therapy field, our company is able to provide gene therapy viral vector purity analysis services at multiple stages of development to accelerate your gene therapy manufacturing process. If you are interested in our services, please feel free to contact us for more details.


  • Wright, J. F. Product-related impurities in clinical-grade recombinant AAV vectors: characterization and risk assessment. Biomedicines, 2014, 2(1): 80-97.

All of our services and products are intended for preclinical research use only and cannot be used to diagnose, treat or manage patients.

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