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Biological Methods-based VLP Characterization Service

Biological Methods-based VLP Characterization Service

CD BioSciences is a leading global company with advanced equipment and experienced staff. We are committed to helping customers analyze the biological properties of Virus-like particles (VLPs) produced by plants, mainly the binding capacity of functional epitopes to antibodies.

Biological Methods for VLP Characterization

The biological characterization of VLPs are often conducted by analyzing the binding of functional epitopes of VLPs to a panel of specific monoclonal antibodies. This binding activity is a preferred indicator of the safety and efficacy of the vaccine in vivo. Various immunoassay methods such as surface plasmon resonance (SRP), and enzyme-linked immunosorbent assay (ELISA), have been used to analyze antibody binding affinity to VLPs.



ELISA is a simple and rapid technique commonly used to analyze biomolecular interactions and can be used to detect and quantify antibodies or antigens attached to solid surfaces. As one of the most sensitive immunoassays, ELISA is widely used as a research tool and is a diagnostic method frequently used in clinical practice. There are four common types of ELISA assays: direct ELISA, indirect ELISA, sandwich ELISA and competition ELISA.

ELISA Classification

Method Advantages Disadvantages Optimal use
Direct ELISA
  • Fast
  • Low cross-reactivity
  • High background
  • Poor flexibility
  • Low sensitivity
Analysis of the immune response to antigens.
Indirect ELISA
  • High sensitivity
  • Economy
  • High flexibility
  • Cross-reactivity
Determination of the concentration of total antibody in the sample
Sandwich ELISA
  • High sensitivity
  • Good specificity
  • High flexibility
  • High requirements for paired antibodies
Analysis of complex samples
Competition ELISA
  • No sample preparation
  • required
  • Good repeatability
  • High flexibility
  • Good stability
  • Cumbersome to operate
Where only one antibody is available for the target antigen


The ability of VLPs to bind to the body's antibodies varies depending on the expression level and functional stability of the VLPs. Therefore, it is far from enough to explore the binding ability of VLPs and antibodies only based on ELISA. ELISA is a marker-based method and markers may impair the function of VLPs. Surface plasmon resonance (SPR) is an optical phenomenon that can be used to track the interactions between biomolecules in their natural state in real time. This method is non-destructive to biomolecules and does not require any markers. SPR therefore offers an attractive alternative biological approach to explore the ability of VLPs to bind to antibodies.

SPR detection systemSPR detection system. (Hearty S, et al., 2018)

Our Services

CD BioSciences offers biological assays (ELISA and SPR) for the ability to bind VLPs to antibodies. We are committed to providing a fast, high quality service at competitive prices to our customers worldwide. We also offer biophysical and biochemical methods for characterization of VLPs, which you can learn more about by following the link. If you are interested in our services, please contact us for more details and we will respond promptly.

Why Choose CD BioSciences


Experienced: We have long provided global clients with a variety of biochemical, biophysical and biological methods to characterize VLPs constructed on plant platforms. In turn, help customers realize the development of vaccines, nanomaterials and diagnostic reagents based on VLPs.

Advanced Equipment

Advanced Equipment: Our laboratory is equipped with the latest and most advanced instrumentation to perform the characterization of VLPs with almost laboratory methods to suit your needs.


Customer-First: From the inquiry to the delivery of the results, we will respond to your messages in a timely manner, keep in touch with you all the time, and provide you with the best experimental plan.


  1. Hearty S.; et al., Measuring Antibody-Antigen Binding Kinetics Using Surface Plasmon Resonance. Methods Mol Biol. 2018, 1827:421-455.
For Research Use Only.

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