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Chemical Conjugation-based VLP Modification Service

Chemical Conjugation-based VLP Modification Service

As a leading global provider of custom services, CD BioSciences has always been committed to providing highly customized and comprehensive solutions that advance our clients' projects with the best quality. Our experienced scientists are happy to meet each specific client requirement and provide the most appropriate solution. CD BioSciences has a sophisticated VLPlantTM platform and extensive experience in modifying VLPs by chemical conjugation to produce chimeric virus-like particles (cVLPs) for your development of vaccines, nanomaterials and diagnostics.

Overview of Chemical Conjugation-based VLP Modification

Coronavirus Structure

To overcome the disadvantages of being limited by antigen size, conformation and assembly of VLPs when constructing cVLPs using genetic fusion methods. We offer chemical conjugation methods to construct cVLP from VLPs generated from plant platforms. In this strategy, the target antigen and VLPs are first produced separately and subsequently linked together by attaching the antigen to the surface of the VLPs. Antigens can be covalently or non-covalently bonded to VLPs constructed from plant platforms to form cVLPs. The most common covalent method is through the use of heterobifunctional chemical crosslinkers with amine and sulfhydryl reactive arms. For example, cysteine-containing antigens can be embedded to VLPs with amino acid residues on their surface. Non-covalent coupling strategies include the use of streptavidin as a junction to link biotinylated antigens and VLPs through their specificity and strong interactions.

Advantages of Chemical Conjugation

This approach allows for the attachment of antigens of different sizes and types to VLPs, including non-protein antigens, and also allows for the manipulation of the binding sites of antigens to VLPs to maximize exposure of conjugated antigens. This ability is essential for the development of vaccines against pathogens with antigenic versatility, as larger proteins are more effective than shorter peptides at eliciting antibodies and eliciting an immune response.

Common conjugation chemistriesCommon conjugation chemistries. (Rohovie MJ, et al., 2017)

Our Services

CD BioSciences provides customers worldwide with chemical conjugation methods for virtually all modifications of VLPs. If you are interested in our services, please contact us for more details and.

  • Covalent Bonds-based VLP Modification Service
    Cysteine-based VLP Modification Service
    CD BioSciences offers VLP modification based on cysteine modification: VLPs and ligands (proteins, peptides, PEG, etc.) are activated with maleimide at pH between 6.5 and 7.5 and then irreversibly bound by thioether bonds in the presence of heterojunctions to produce cVLPs.
    Lysine-based VLP Modification Service
    CD BioSciences offers VLP modification based on lysine modification: VLPs and. ligands (peptides, fluorescent probes, proteins,etc.) are first activated using maleimide, and then when the pH is between 7.2 and 9, lysine residues exposed on the surface of VLPs and ligands can form amide bonds through ester reactions of n-hydroxysuccinimide (NHS), resulting in cVLPs.

    Acidic Amino Acids-based VLP Modification Service
    CD BioSciences offers services for the modification of VLPs based on acidic amino acids (aspartic acid and glutamic acid).

    Nonnatural Amino Acid-based VLP Modification Service
    CD BioSciences provides customers with surface functionalization of VLPs based on unnatural amino acids, which in turn produces cVLPs by linking ligands (peptides, proteins, fluorescent probes, antibodies, etc.) to VLPs via click chemistry (azide-alkyl cyclization).

  • Noncovalent Bonds-based VLP Modification Service
    CD BioSciences provides services for the modification of VLPs by noncovalent bonding methods (based on chain affinity-biotinylation technology).

Advantages of Our Services

Advantages of Our Services

CD BioSciences also provide VLPs construction through different plant platforms, VLPs purification and VLPs characterization assay services, if you are interested, please feel free to contact us.


  1. Rohovie MJ.; et al., Virus-like particles: Next-generation nanoparticles for targeted therapeutic delivery. Bioeng Transl Med. 2017, 2:43-57.
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