3,000+ DNA/RNA modification options with expert design help, fast quoting, and ISO/GLP/GMP-aligned workflows. Build exactly what your assay or program needs — fluorescent probes, conjugates, delivery lipids, caps, chelators, and more.
BSI offers one of the broadest portfolios of phosphoramidite-based reagents to support research, diagnostics, sequencing, and therapeutic development. Our Oligonucleotide Modifications Reference Guide helps you choose the right modification—or combination—for your application.
With over 3000 options and growing, we deliver high-quality, custom-modified oligonucleotides backed by expert technical support. If the modification you need is not listed, contact us—our team can provide tailored solutions to meet your specific requirements.
If the modification you need is not listed, please don’t hesitate to contact us—our team is ready to assist with custom solutions tailored to your specific requirements.
Browse key modification families. Each card summarizes what it is and common uses. Click any card to jump to details.
Tune duplex stability, add labels, tolerate polymorphisms in primers/probes, model DNA damage/marks.
Epitranscriptomics mapping, RNA stability and translation studies, fluorescent RNA probes.
Increase nuclease resistance, raise/lower Tm, control conformation in ASOs/siRNA/diagnostics.
Adjust charge and stability, enable RNase‑H compatibility, enhance durability in vivo.
Enable ligation, prevent extension or degradation, add capture/labeling handles.
Enable internal fluorophores or haptens, add click handles, introduce cross-linking points, or probe folding and binding.
Enhance mRNA stability and translation, reduce immunogenicity, and study cap-binding proteins.
Add detection, targeting, or delivery functions; build antibody-oligo, drug-oligo, or nanoparticle conjugates; improve biodistribution.
Improve membrane association and uptake, extend serum half-life, and support nanoparticle assembly.
Covalent capture of interactions, footprinting, mapping contacts under UV/visible light.
Affinity capture (streptavidin) or antibody‑based detection in blots, ISH/FISH, ELISAs.
Enzyme Oligo Conjugates capture (streptavidin) or antibody‑based detection in blots, ISH/FISH, ELISAs.
Optimize FRET, minimize quenching, tune geometry and accessibility for enzymes/targets.
Signal amplification, multivalent targeting, barcoded assemblies and scaffolds.
Condition‑triggered release vs. stable attachment, controlled delivery and tracking.
qPCR/probes, imaging, FRET pairs, single‑molecule and multiplex detection.
Report on base stacking and environment, serve as FRET donors/acceptors, and monitor conformational changes or hybridization in real time.
Non‑emissive or dark quenchers to suppress donor fluorescence until target binding/cleavage.
Radiolabeling (PET/SPECT), lanthanide labeling, metal‑assisted capture and imaging.
Stabilize or probe structure, create MGB effects, tune Tm and signal.
Photocrosslink/cleavage, crystallography phasing, structure‑function studies.
azide/alkyne (CuAAC), DBCO/BCN (SPAAC), TCO/tetrazine (IEDDA), thiol-maleimide, NHS-ester/amine, and aldehyde-oxime/hydrazone workflows.
E‑DNA/E‑RNA biosensors, label‑based voltammetry, point‑of‑care diagnostics.
Puromycin, doxorubicin, folic acid, tocopherol and ferrocene.
Our scientists will recommend the best option to fit your assay, conjugation strategy, or delivery needs — and guide you from design through QC.
You can request a quote or contact our team for custom synthesis through the contact form below.
We provide HPLC, PAGE, mass spectrometry, and additional QC options depending on your needs.
Yes, GMP and GLP-grade oligos are available on request with full documentation and traceability.
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