CDMO-ready PAMAM dendrimer–oligonucleotide conjugation for siRNA, ASO, PNA, and PMO programs — supporting covalent PAMAM–oligo conjugates and dendriplex delivery systems with generation selection (G1–G7+), site control, cleavable linker options, purification, and CMC-aligned analytics from feasibility through scale-up.
PAMAM (polyamidoamine) dendrimers are monodisperse, generation-defined macromolecules with multivalent surface functionality. Their branched architecture enables high-density oligonucleotide attachment (covalent conjugates) or electrostatic complexation (dendriplex systems), supporting delivery and intracellular release designs for therapeutic nucleic acids.
As an oligonucleotide CDMO, we integrate dendrimer generation selection, end-group functionalization, conjugation chemistry, purification, and analytical characterization to reduce development risk and accelerate preclinical readiness for siRNA, ASO/SSO, PNA, and PMO programs.
Typical workflows begin with feasibility builds (mg scale) to establish architecture and CQAs, followed by optimization of shielding (e.g., partial PEGylation), linker stability (stable vs cleavable), and formulation parameters (N/P, media stability) for scale-up.
Quick facts
The best PAMAM architecture is the smallest generation and minimal surface charge needed to reach your delivery and release goal.
Generation range
Two build modes
Control Oligo- Dendrimer Ratio and Attachment Site using orthogonal handles for reproducible, characterizable constructs.
Screen N/P ratio, shielding, and buffer systems to balance uptake, stability, unpacking, and tolerability.
Define conjugation completeness, residual reagents, size/zeta, stability, and release to support scalable execution.
Covalent attachment provides defined stoichiometry and improved batch-to-batch reproducibility for downstream analytics and scale-up.
Electrostatic complexation is tuned through N/P ratio, ionic strength, shielding, and serum stability to balance uptake and release.
Partial PEGylation and Ligand installation can reduce surface charge density and tune biodistribution while maintaining multivalency.
PAMAM generation influences surface group density, loading capacity, buffering behavior, and interaction strength. We commonly start with G4–G5 for screening, then adjust generation and shielding to meet the desired balance of delivery and biocompatibility.
Chemistry selection is driven by the installed oligo handle, PAMAM surface functionality, buffer compatibility, and the intended stability profile (stable vs cleavable). We design coupling workflows to minimize side reactions and streamline purification.
Activated esters form stable amide linkages with PAMAM surface amines; avoid competing nucleophiles during coupling.
Site-Specific Thioether formation using 5′/3′ Thiolated Oligos; control pH and protect thiols from oxidation.
Copper-free click coupling for sensitive payloads; consider solubility of hydrophobic click handles.
Loading ratio, residual reagents, SEC/GPC profile, HPLC/UPLC purity, and LC-MS where applicable.
N/P ratio, size/PDI, zeta potential, stability in relevant media, and release/functional readouts.
Storage stability and linker integrity; evaluate unpacking/release and activity retention over time.
Use internal links to build topical authority around oligonucleotide conjugation and delivery.
PLGA/PLA/PCL/PBAE and polymer-enabled delivery architectures with release profiling.
Linear vs branched vs multi-arm PEG and dPEG spacers with site control.
Hepatocyte-targeted conjugation formats and linker selection support.
Hydrophobic conjugation strategies for tissue targeting and uptake tuning.
Pillar page tying synthesis, conjugation, delivery, analytics, and scale-up together.
Covalent conjugates offer defined stoichiometry and reproducible architecture. Dendriplex systems are formulation-tunable via N/P ratio and shielding, but require stability/unpacking optimization.
G4–G5 are common starting points for siRNA/ASO screening. Higher generations increase loading but often require shielding to manage cytotoxicity and nonspecific interactions.
NHS–amine coupling, maleimide–thiol coupling, and copper-free click (SPAAC) are widely used. Cleavable linkers can be added for intracellular release designs.
Define loading ratio, purity, residual reagents, and stability early. For dendriplex systems, include N/P ratio, size/PDI, zeta potential, and stability in relevant media.
Yes. We support PNA and PMO conjugation using appropriate handles and coupling strategies, with purification and characterization tailored to the construct and analytical needs.
Yes. Partial PEGylation and ligand installation can reduce surface charge and tune interactions. We recommend a minimal modification strategy that preserves delivery performance.
Share your payload (siRNA/ASO/PNA/PMO), preferred format (covalent vs dendriplex), target generation, handle placement (5′/3′/internal), linker preference (stable vs cleavable), and desired scale. We will recommend architecture, coupling chemistry, purification strategy, and analytics package.
Peer‑reviewed references on PAMAM dendrimer generation effects, dendrimer–oligonucleotide complexation (polyplex / dendriplex), shielding/targeting, intracellular trafficking, and practical screening workflows.
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