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Oligonucleotide Conjugate Discovery
Delivering the oligonucleotide to a specific cell or tissue, and tuning its drug-like properties.
What a conjugate program has to source
Oligonucleotide conjugates create opportunities to deliver the sequence to a specific cell or tissue and to fine-tune its drug-like properties. The conjugation chemistry is where the complexity sits.
A conjugate program rarely runs late because that chemistry fails. More often the sequence comes from one supplier, the ligand from a second and the linker from a third, and each handover brings a new set of analytical methods, a new impurity discussion and a shipment waiting on customs.
Our capability covers oligonucleotides, peptides and small molecules, which means ligands, toxins, linkers, lipids and PEG are all made here, with design, synthesis and analytical support at any scale.
Discovery capabilities
Conjugation capabilities
Conjugate types
Existing peptide-drug conjugate image
Reference candidate only; not a peptide-oligonucleotide image
Library images are illustrative; specific molecular structures have not been verified.
Topology
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3′ or 5′ end conjugation
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Oligonucleotide moiety conjugates on base and phosphorus backbones
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Complex dual conjugation: 3′,5′, 3′,3′ and 5′,5′
Attachment diagrams pending scientific review.
Conjugation chemistry
- Amide coupling
- Thiol-maleimide addition
- Click chemistry: CuAAC and SPAAC
- Disulfide chemistry
- Hydrazone chemistry
Conjugation runs either after synthesis, including post-ultrafiltration and diafiltration workflows, or during solid-phase assembly itself, using amidite-based 5′ modification or custom-loaded supports for 3′ attachment. Building the conjugation into the assembly means several linker geometries can be tested in one campaign.
Linkers and ligands
- More than 50 modified polystyrene and CPG resins: GalNAc, lipid and PEG amine, biotin, dye
- More than 100 peptide conjugates: cell-penetrating peptide, cyclic peptide, bicyclic peptide
- More than 150 cleavable and uncleavable linkers with maleimide, DBCO, BCN, azide and PySS handles
For liver-targeted work, GalNAc is made in-house: more than 100 types including mono-, tri- and tetra-GalNAc, GalNAc amidite, PFP ester, azide and PEG conjugates.
Discovery in practice
Conjugation for discovery
Ligand screening · Peptide conjugation · siRNA-ASO
Case studies
Conjugation in practice
| Case study | Results |
|---|---|
| Dual conjugation | 140 complex dual conjugates 4–6 weeks |
| siRNA-peptide | SEC purity above 90% Ultrafiltration purification |
| siRNA-ASO | 14 conjugates · 5 weeks SEC purity by UPLC above 90% |
Featured case study
Dual conjugation for fast ligand screening
Dual conjugation allows two ligands to be screened on one siRNA. Using it we ran a two-dimensional screen of the affinity of two ligand types, which raised screening efficiency sharply and gave lead optimization for 140 complex dual conjugates in four to six weeks.
siRNA-peptide conjugation
We prepared the siRNA and the cyclic peptides, then performed the conjugation with the cyclic peptide after siRNA annealing. SEC purity was held above 90%, with purification by our ultrafiltration technology.
siRNA-ASO conjugation
We prepared 5′ SH and N3 ASO and siRNA in-house and delivered 14 conjugates within five weeks, at SEC purity by UPLC above 90%.
Peptide-oligonucleotide conjugates
One-stop POC synthesis, with more than 10 years of experience in both oligonucleotide and peptide chemistry, and more than 80 peptides, lipids and PEG linkers readily available for conjugation. Linker and conjugation chemistry, including dual conjugation, is custom-tailored per program.
Design decisions made with scale-up in view
The linker chemistry that works on 50 mg does not always work on 5 kg, and the conjugation strategy chosen in discovery is usually the one carried to IND. Because process development runs in the same organization, scale-up feasibility can be assessed while several leads are still open.
Tell us which components the conjugate needs
Our quality
Quality is embedded in every oligonucleotide conjugate we deliver. We apply meticulous controls, thorough characterization, and proven processes to ensure each conjugate meets tight specifications for purity, stability, and performance.
Complexity drives us forward – never at the expense of precision. With clear documentation and experienced teams, we turn potential obstacles into dependable outcomes. It’s how we deliver conjugates you can trust to advance with confidence from discovery through development.
Our locations
Our global network supports oligonucleotide conjugate development with flexibility and local access. Strategically located sites in China, Singapore, Switzerland, and the U.S. provide integrated synthesis, conjugation, and scale-up capabilities.
This connected footprint helps keep complex projects moving without bottlenecks or delays. Combining deep specialism with regional support means you can progress discovery through commercial manufacturing confidently – knowing you have precise, responsive capacity wherever you need it to advance your oligonucleotide therapies.
Our history
From its foundation, our journey has been defined by a commitment to innovation, quality, and strong partnerships, driven by a purpose-driven pace.
We’ve evolved into a leading CRDMO with a perfectly orchestrated platform, consistently expanding our global footprint and capabilities to accelerate breakthroughs for our partners and patients worldwide.
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