Dendrimer-Cationic Moiety Conjugation Service

Dendrimers modified with cationic moieties have increased surface charge density and improved cytotoxicity and transfection efficiency. As a leading customer-focused global biotechnology company, CD BioSciences has built a robust dendrimer modification platform for improving the properties of dendrimers to meet customer requirements. Our experienced scientists can help customers develop effective dendrimer modification strategies to meet the growing global demand for dendrimers.

Dendrimer-Cationic Moiety Conjugation Improves Transfection Efficiency

Cationic dendrimers with primary amine groups on the surface, modified by other cationic moieties (e.g., oligoamine, tertiary amine, quaternary ammonium, imidazolium, guanidium, and phosphonium), have reduced cytotoxicity and increased transfection efficiency.

• Dendrimer-Oligoamine Conjugation
  Dendrimers modified with oligoamines have an odd-even effect in gene transfection, as shown by the fact that the oligoamines with even-numbered repeating aminoethylene units show significantly higher transfection efficacy than those with odd-numbered aminoethylene units when grafted on a linear polymer. This is because oligoamines modified with even-numbered aminoethylene units have high buffering capacity and high activity in destabilizing membrane integrity selectively at endosomal pH. In addition, this parity effect of oligoamines is also applicable to other types of dendrimers, for example, polyglycerol and Newkome-type "arborol". Because the transfection efficiency of cationic polymers depends on several parameters, the transfection effect of oligoamine modified dendrimers is not always proportional to the length of the oligoamine. Dendrimers modified by longer oligoamines are beneficial for DNA condensation, but it might be harmful for DNA unpacking in the cytoplasm after endosomal escape.

Two-step synthesis of oligoamines-functionalized dendrimer. (Fischer W, et al., 2010)

• Dendrimer-Tertiary Amine/Quaternary Ammonium Conjugation
  Dendrimers modified with tertiary amines and quaternary ammonium have reduced cytotoxicity and are used as carriers for in vivo and in vitro gene delivery, mainly for the treatment of HIV. For example, quaternized carbosilane dendrimers can successfully deliver antisense oligonucleotides (asODN) and siRNAs to a range of cells associated with HIV pathology.

Structures of tertiary amine/quaternary ammonium-modified dendrimers. (Tambe V, et al., 2017)

• Dendrimer-Guanidium/Imidazolium Conjugation
  Dendrimers modified by guanidium, and imidazolium also improve transfection efficiency, with a mechanism of action like that of arginine-modified and histidine-modified dendrimers, respectively. Compared to commercial transfection reagents, triphenylphosphonium (TPP)-modified PAMAM dendrimers show high transfection efficiency and low cytotoxicity due to their mitochondrial targeting ability, which facilitates endosomal escape and membrane disruption during intracellular transport.

Synthetic route of TPP-functionalized G5 PAMAM dendrimers. (Wang X, et al., 2014)

Our Services

As a customer focused and trusted CRO, CD BioSciences has a proven technology platform and experienced scientists to advance the engineering of dendrimers to meet our customers' needs. When it comes to cationic moiety modification of dendrimers, we are confident that we can provide you with the highest quality service and are committed to meeting our customers' needs in an environmentally sustainable and cost-effective manner. Our services include but are not limited to:

• Oligoamines-Modified Dendrimers
  We improve the service of modifying dendrimers with oligoamines to reduce their charge density. When dendrimers modified with oligoamines are used as transfection reagents, transfection efficiency is increased, and cytotoxicity is reduced.
• Tertiary Amine/Quaternary Ammonium-Modified Dendrimers
  When dendrimers are used as vectors for in vivo or in vitro gene delivery, we can modify them with tertiary amines and quaternary ammonium to reduce cytotoxicity.
• Guanidium/Imidazolium-Modified Dendrimers
  We improve the transfection efficiency and cytotoxicity of dendrimers by modifying them with guanidine and imidazole.

Why Choose Us?

Want to Learn More?

With sophisticated facilities and an experienced research team, CD BioSciences is committed to helping our customers meet their needs for dendrimer modification services and products. All our deliverables will be delivered on time and undergo a rigorous quality testing process to ensure reliability. Contact us now to start moving forward with your attractive project.

References

1. Fischer W, et al., Dendritic polyglycerols with oligoamine shells show low toxicity and high siRNA transfection efficiency in vitro. Bioconjug Chem.2010, 21: 1744-52.
2. Tambe V, et al., Surface Engineered Dendrimers in siRNA Delivery and Gene Silencing. Curr Pharm Des. 2017, 23: 2952-2975.
3. Wang X, et al., Mitochondrial targeting dendrimer allows efficient and safe gene delivery. J Mater Chem B.2014, 2: 2546-2553