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Custom siRNA Synthesis Services

High-purity custom siRNA synthesis for RNA interference (RNAi) and gene silencing. Designed for functional genomics, in vivo studies, and therapeutic development, with advanced chemical modifications, delivery conjugation, and scalable production up to 100 g+ batches.

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Overview

ISO 9001:2015 / ISO13485:2016 45+ Years of Expertise U.S.A. Facilities-Texas GLP/GMP-Aligned Custom siRNA Triplex RNA 100 g+ batch capability Thousands of modifications

Custom siRNA synthesis is the production of sequence-specific small interfering RNA (siRNA) molecules designed to silence target genes through RNA interference (RNAi). These synthetic RNA duplexes bind complementary mRNA and trigger its degradation, resulting in reduced protein expression.

siRNA is widely used in functional genomics, target validation, pathway analysis, and therapeutic research because it provides precise, reversible gene knockdown without permanently altering the genome.

Bio-Synthesis offers custom siRNA synthesis with flexible design formats, advanced chemical modifications, and scalable production from research quantities to 100 g+ batch manufacturing, supporting applications from early discovery through preclinical development.

What you can configure

Custom siRNA programs can be configured by sequence, strand design, construct format, chemical modification pattern, purification grade, delivery strategy, and quality control requirements. Capabilities include standard 21-mer siRNA, 19-mer blunt duplexes, 25–27 nt Dicer-substrate siRNA, custom-length constructs, duplex siRNA, triplex siRNA, self-annealed duplex designs, pooled siRNA sets, delivery-conjugated siRNA, and large-scale manufacturing for qualified programs.

Scale

100 g+

Batch production capability for qualified projects

Formats

21 / 19 / 27 nt+

Standard, custom-length, triplex, and self-annealed designs

Chemistry

1000s

Modification, linker, and conjugation options

QC

MS + HPLC

Identity, purity, quantitation, and optional testing

What is siRNA Technology and What Are Its Benefits?

siRNA technology is a gene-silencing approach based on RNA interference (RNAi). Small interfering RNA molecules are designed to recognize a specific messenger RNA (mRNA) sequence and guide its degradation, reducing production of the target protein.

The diagram below illustrates how siRNA mediates gene silencing through RNA interference (RNAi).

siRNA mechanism showing RNA interference process where siRNA binds mRNA and causes gene silencing via RISC complex

Mechanism of RNA interference (RNAi): siRNA is incorporated into the RISC complex, binds complementary mRNA, and induces cleavage leading to gene silencing.

Because siRNA acts at the mRNA level without permanently editing the genome, it provides a powerful and flexible method for studying gene function, validating drug targets, analyzing disease pathways, and developing RNA-based therapeutic strategies. Custom siRNA can be optimized through sequence design, chemical modification, purification, and delivery conjugation to improve potency, stability, specificity, and in vivo performance.

Targeted Gene Silencing

siRNA enables sequence-specific knockdown of target genes, making it useful for functional genomics, disease pathway research, and therapeutic target validation.

Flexible Design Formats

Available formats include standard 21-mer duplex siRNA, 19-mer blunt duplexes, 25–27 nt Dicer-substrate siRNA, custom-length constructs, triplex siRNA, and self-annealed duplex designs.

Improved Stability

2′-OMe, 2′-F, LNA/BNA, phosphorothioate linkages, terminal protection, and other modifications can improve nuclease resistance and biological performance.

Delivery-Ready Options

siRNA is prepared for transfection, lipid nanoparticle workflows, GalNAc targeting, cholesterol or lipid conjugation, peptide conjugation, antibody conjugation, and other delivery strategies.

Research to Preclinical Scale

Projects can scale from screening quantities and pooled siRNA sets to gram-scale and 100 g+ batch production for qualified development programs.

Application-Specific QC

Quality control options include mass spectrometry, analytical HPLC, OD260 quantitation, duplex confirmation, endotoxin testing, RNase testing, Tm analysis, and additional project-specific assays.

Benefit Why it matters Typical siRNA strategy
Specific knockdown Reduces expression of a selected target gene without permanently editing the genome. Sequence-optimized guide strand with appropriate negative and positive controls.
Fast experimental timeline Supports rapid target validation compared with stable genetic manipulation approaches. Standard duplex siRNA or pooled siRNA for screening and confirmation studies.
Enhanced stability Improves resistance to nucleases and supports longer biological activity. 2′-OMe, 2′-F, LNA/BNA, PS end-caps, and terminal protection.
Improved delivery Supports cellular uptake, tissue targeting, and in vivo performance. GalNAc, cholesterol, lipid, peptide, PEG, antibody, or small-molecule conjugates.
Development flexibility Allows progression from discovery assays to preclinical oligonucleotide programs. Custom length, duplex/triplex/self-annealed architectures, scalable synthesis, and expanded QC.

For best results, siRNA design should consider target sequence accessibility, GC content, off-target risk, strand bias, chemical modification placement, delivery method, and assay conditions. Our team can help configure siRNA constructs based on research goals, application type, scale, and downstream testing requirements.

Custom siRNA Synthesis Options

Configure your siRNA by format, strand design, modification pattern, purification grade, delivery format, and documentation needs.

Flexible construct formats: Available formats include standard 21-mer duplex siRNA, 19-mer blunt duplexes, 25–27 nt Dicer-substrate siRNA, and custom-length RNA constructs. Options include duplex siRNA, triplex siRNA, self-annealed duplex designs, custom single strands, pooled siRNA sets, and non-standard architectures for specialized research and development programs.

Parameter Standard offering Additional options
Format 21-mer duplex with 2-nt 3′ overhangs; 19-mer blunt duplex; 25–27 nt Dicer-substrate siRNA; custom-length siRNA constructs custom-length single strands; duplex siRNA; triplex siRNA; self-annealed duplex designs; pooled siRNA sets
Strand design Annotated guide / passenger strands 5′ phosphate guide strand; custom polarity, overhang, or blocked-end designs
Modification design 2′-OMe, 2′-F, LNA, PS end-caps, terminal protections Custom modification maps, mixed chemistry patterns, labels, linkers, and conjugates
Purification RP-HPLC, IEX-HPLC, or RNase-controlled HPLC PAGE or dual HPLC for complex constructs and higher purity needs
Delivery format Lyophilized sodium salt or annealed duplex Single-strand delivery, buffer exchange, counter-ion exchange, or project-specific formulation support
Scale Small research quantities through gram scale Large-scale 100 g+ batch production for qualified programs

siRNA Design Principles for Potency and Specificity

Successful siRNA performance depends on thoughtful sequence selection, strand orientation, modification strategy, delivery method, and appropriate controls. Standard and advanced siRNA designs are available for research, in vivo, and development programs.

Core siRNA Design Checklist

  • Format: 21-mer siRNA with 2-nt 3′ overhangs, 19-mer blunt duplexes, 25–27 nt Dicer-substrate siRNA, or custom-length constructs.
  • Guide/passenger orientation: Annotate antisense guide and sense passenger strands for correct duplex assembly.
  • Thermodynamic bias: Weaken the 5′ end of the guide strand to favor guide-strand loading.
  • Seed review: Review guide positions 2–8 to reduce off-target risk.
  • GC content: Target approximately 30–55% GC and avoid long homopolymers.
  • Controls: Include scrambled, mismatch, positive, or pooled siRNA controls when appropriate.

Stability and Specificity Strategy

  • 2′ modifications: Use 2′-OMe, 2′-F, LNA, BNA, ENA, FANA, UNA, or related chemistries to improve nuclease resistance and potency.
  • PS end-caps: Add 1–3 phosphorothioate linkages at termini to increase exonuclease resistance.
  • Guide 5′ phosphate: Add 5′ phosphorylation when needed to support RISC loading.
  • Sense-strand tuning: Use passenger-strand deactivation strategies to reduce unintended strand activity.
  • Reduced immunostimulation: Use strategic 2′-OMe substitutions and motif review to reduce innate immune activation.
  • Pooling: Use 3–4 siRNA pools to reduce single-sequence artifacts.

siRNA Modifications, Linkers, and Conjugation Chemistry

siRNA modifications, linkers, and conjugation chemistry improve nuclease resistance, reduce off-target effects, enhance potency, enable tracking, and create application-specific siRNA constructs. Available chemistry includes sugar modifications, backbone modifications, terminal protection, fluorophores, affinity tags, reactive handles, spacers, cleavable linkers, and delivery-oriented conjugation handles.

Modification strategies are selected based on sequence, strand design, biological system, scale, purification, QC, and downstream application requirements. Thousands of modification and linker combinations are available for research, imaging, screening, in vivo, and preclinical oligonucleotide programs.

Modification category Examples Primary purpose
Sugar modifications 2′-O-methyl RNA, 2′-fluoro RNA, LNA/BNA, ENA, FANA, UNA and selected custom sugar chemistries Improve nuclease resistance, potency, serum stability, and biological performance.
Backbone modifications Phosphorothioate (PS) linkages, partial PS patterns, terminal PS end-caps, specialty linkage designs Increase exonuclease resistance, tune protein binding, and improve in vivo durability.
Terminal protection Inverted dT, Spacer C3, 3′ blockers, 5′ phosphate, terminal caps, protected ends Protect strand ends, support guide-strand function, and control strand activity.
Spacers and linkers AEEA, PEG linkers, C3/C6/C12 spacers, Ahx, cleavable linkers, disulfide linkers, acid-labile linkers Provide spacing, flexibility, solubility, controlled release, and conjugation positioning.
Fluorescent labels FAM, HEX, TAMRA, ROX, Cy3, Cy5, ATTO dyes, Alexa Fluor options Enable uptake studies, imaging, localization, trafficking, and assay readout.
Affinity tags Biotin, desthiobiotin, digoxigenin, affinity capture handles Support pull-down, detection, immobilization, enrichment, and analytical workflows.
Reactive handles Amine, thiol, azide, alkyne, DBCO, BCN, maleimide, NHS ester-compatible formats Enable custom bioconjugation to peptides, proteins, antibodies, polymers, ligands, and surfaces.
Delivery-oriented conjugates GalNAc, cholesterol, lipids, peptides, PEG, small molecules, targeting ligands Support cellular uptake, tissue targeting, formulation compatibility, and in vivo delivery strategies.

Stability Modifications

Stabilizing modifications are commonly used to protect siRNA from nuclease degradation and improve performance in serum, cell culture, and in vivo environments.

  • 2′-O-methyl and 2′-fluoro RNA
  • LNA/BNA and selected sugar variants
  • Phosphorothioate end protection
  • Terminal capping and protected ends

Linkers and Spacers

Linker chemistry can control distance, flexibility, solubility, release behavior, and attachment orientation between siRNA and a label, ligand, peptide, polymer, or carrier.

  • PEG and AEEA linkers
  • C3, C6, C12, and Ahx spacers
  • Cleavable and non-cleavable linkers
  • Disulfide, acid-labile, and click-compatible linkers

Labels and Reactive Handles

Functional tags and reactive groups enable imaging, tracking, affinity capture, immobilization, and downstream conjugation to delivery or targeting groups.

  • FAM, Cy3, Cy5, TAMRA, ATTO, Alexa Fluor
  • Biotin and digoxigenin
  • Amine, thiol, azide, alkyne, DBCO, BCN
  • Maleimide and NHS-compatible conjugation approaches
Application goal Recommended chemistry considerations Typical examples
Cell-based knockdown Balance potency, low toxicity, and reduced off-target effects. 2′-OMe seed modification, optional 5′ phosphate, HPLC-purified duplex siRNA.
In vivo gene silencing Increase nuclease resistance, reduce immunostimulation, and support delivery. 2′-OMe / 2′-F patterns, PS end-caps, GalNAc or lipid conjugates, endotoxin-controlled processing.
Uptake and imaging Add a fluorophore with proper spacing to reduce disruption of duplex function. FAM, Cy3, Cy5, or ATTO label with AEEA or PEG spacer.
Affinity capture Use tags that support enrichment or immobilization without interfering with the guide strand. Biotinylated sense strand, spacer arm, HPLC purification.
Custom bioconjugation Select a reactive handle and linker compatible with the partner molecule and reaction conditions. Azide-alkyne click chemistry, DBCO/azide SPAAC, thiol-maleimide, amine-NHS coupling.

Custom modification planning: The best siRNA chemistry depends on the target sequence, strand design, delivery method, biological system, scale, and QC requirements. Bio-Synthesis can help configure modification placement, linker selection, conjugation handle, purification method, and analytical testing for your specific program.

siRNA Drug Delivery Strategies and Bioconjugation Options

Effective siRNA delivery is essential for gene silencing performance. siRNA molecules can be delivered using lipid-based systems, ligand conjugation, peptide conjugation, polymer-based carriers, nanoparticle formulations, or other application-specific delivery strategies depending on the target cell, tissue, route of administration, and research or development goal.

The diagram below compares common siRNA delivery strategies used in research and therapeutic development.

comparison of siRNA delivery methods including lipid nanoparticles LNP GalNAc conjugation peptide conjugates and cholesterol lipid delivery systems

Comparison of siRNA delivery approaches including lipid nanoparticles (LNP), GalNAc conjugates, peptide-based delivery, and lipid-modified siRNA systems.

Custom siRNA programs can include bioconjugation, delivery-oriented modification patterns, and scalable production for in vitro knockdown studies, in vivo research, and preclinical development workflows.

Delivery strategy Examples Typical use case
Lipid nanoparticles (LNPs) Ionizable lipid systems, helper lipids, cholesterol, PEG-lipid components In vivo delivery, systemic administration, formulation-driven development programs
GalNAc-siRNA conjugates Triantennary GalNAc, cleavable or stable linkers, amide or click-based attachment Hepatocyte targeting through ASGPR-mediated uptake for liver-focused programs
Cholesterol and lipid conjugates Cholesterol, tocopherol, stearyl, lipid anchors, hydrophobic linker systems Improved membrane association, uptake enhancement, and formulation compatibility
Peptide-siRNA conjugates Cell-penetrating peptides, targeting peptides, CPPs, receptor-binding peptides Cellular uptake studies, targeted delivery concepts, and tissue-specific research applications
Polymer / PEG-siRNA conjugates PEG spacers, synthetic polymers, biodegradable polymer concepts, multivalent scaffolds Solubility tuning, spacing control, pharmacokinetic adjustment, and carrier-based delivery
Antibody or protein conjugates Antibody-siRNA, Fab-siRNA, protein-siRNA, maleimide, NHS, click, or bioorthogonal linkers Targeted delivery research, receptor-mediated uptake, and precision delivery workflows
Small molecule conjugates Ligands, receptor-targeting molecules, affinity tags, imaging or tracking groups Target engagement, uptake studies, biodistribution research, and specialized delivery designs

For Cell-Based Studies

Lipid transfection, electroporation, nucleofection, peptide conjugation, and fluorescently labeled siRNA can support in vitro knockdown, uptake, localization, and mechanism studies.

For In Vivo Studies

In vivo siRNA often requires chemical stabilization, endotoxin-controlled processing, and delivery strategies such as GalNAc, lipid conjugates, LNPs, peptide carriers, or polymer-based systems.

For Therapeutic Development

Development programs may require scalable synthesis, custom linker design, controlled conjugation, defined purification, expanded QC, and documentation aligned with the intended application.

Use case Why delivery matters Common siRNA setup
Cell-based knockdown Efficient intracellular delivery is required for RISC loading and target mRNA degradation. 21-mer duplex siRNA, 2′-OMe seed modification, RP-HPLC purification, lipid transfection.
In vivo liver targeting Ligand-mediated delivery improves hepatocyte uptake and tissue selectivity. GalNAc-siRNA with 2′-OMe / 2′-F chemistry and phosphorothioate end protection.
Uptake and localization studies Tracking labels help evaluate delivery efficiency, localization, and cellular trafficking. Fluorophore-labeled siRNA with AEEA, PEG, or other spacer chemistry.
Formulation development Construct chemistry and purity affect compatibility with LNPs and other carrier systems. Modified siRNA, buffer exchange, counter-ion control, high-purity duplex or single strands.
Targeted conjugate research Ligands, peptides, antibodies, or small molecules can direct siRNA toward selected cells or receptors. siRNA with amine, thiol, azide, alkyne, DBCO, BCN, maleimide, or other reactive handles.

The best delivery approach depends on the biological target, cell type, tissue, route of administration, desired duration of knockdown, and downstream assay. Our team can help configure siRNA format, modification pattern, linker chemistry, purification, and QC requirements to match your delivery strategy.

Purification Grades and Development Support

Different siRNA applications require different levels of purity, documentation, and biological control. Flexible purification and quality options are available for screening, cell-based, in vivo, and development-stage programs.

Grade Best fit Description
Desalted Early screening and plate-based assays Removes salts and small-molecule impurities; practical for high-throughput discovery workflows.
RNase-Free HPLC Routine cell-based studies Reverse-phase or ion-exchange HPLC under RNase-controlled workflow to enrich full-length product.
RNase-Free Dual HPLC Sensitive assays or complex chemistries Two orthogonal HPLC steps such as RP + IEX for higher full-length enrichment.
In Vivo Grade Pilot animal studies Nuclease-controlled processing with defined endotoxin and bioburden controls.
In Vivo RNase-Free Dual HPLC Critical in vivo and preclinical studies Dual purification with stringent RNase and endotoxin controls for high-confidence in vivo work.
GLP / cGMP Support Advanced development programs Project-specific support available on request, depending on sequence, chemistry, scale, QC, and regulatory needs.

Quality Control and Manufacturing Support

Standard QC Package

  • Mass spectrometry by ESI or MALDI for strand identity
  • Analytical HPLC for purity assessment
  • OD260 quantitation and concentration reporting
  • Duplex integrity assessment when applicable
  • Lot documentation for traceability

Optional Testing

  • Endotoxin testing by LAL
  • RNase testing
  • Tm / thermal profile
  • Functional knockdown assay support
  • RUO, GLP-aligned, or cGMP support on request

Applications

Cell-Based Gene Knockdown

Use modified or unmodified duplex siRNA to reduce target mRNA expression in cultured cells for mechanistic studies and target validation.

In Vivo Gene Silencing

Configure chemically stabilized and delivery-conjugated siRNA for pilot in vivo studies, pharmacology, biodistribution, and PK/PD workflows.

Pooled Screening

Use 3–4 siRNA pools against a single gene to reduce sequence-specific artifacts and improve confidence in screening workflows.

Imaging and Trafficking

Add fluorescent labels, spacers, or affinity tags to track uptake, localization, and delivery performance.

Therapeutic Development

Advance from research-grade constructs to structured preclinical programs with scalable synthesis, modification planning, and expanded QC.

Custom Complex Constructs

Support non-standard duplexes, specialized overhangs, conjugated constructs, and advanced linker architectures.

FAQ

Why use modified siRNA instead of unmodified siRNA?

Modified siRNA can improve nuclease resistance, serum stability, potency, specificity, delivery compatibility, and in vivo performance. Common modifications include 2′-OMe, 2′-F, LNA/BNA, PS end-caps, and terminal protection.

What siRNA delivery options are available?

Delivery options may include lipid nanoparticles, GalNAc conjugates, cholesterol or lipid conjugates, peptide conjugates, polymer or PEG conjugates, antibody or protein conjugates, and small-molecule targeting ligands. The best choice depends on cell type, tissue target, route of administration, and application.

What is the best siRNA delivery method for cultured cells?

Lipid-based transfection is the most common starting point for many adherent and suspension cells. Electroporation or nucleofection may be better for hard-to-transfect cells such as neurons, stem cells, and immune cells. Polymer-based reagents may be useful for scalable transfection but can require optimization.

Explore TEW--> siRNA modification for in vivo delivery

Can siRNA be ordered in plates?

Yes. Plate-format siRNA orders can support screening projects, pooled designs, and high-throughput workflows. Include plate format, concentration, normalization, and control requirements in the quote request.

How can I reduce siRNA off-target effects?

Use guide seed review, avoid problematic motifs, consider 2′-OMe modification in the seed region, tune or deactivate the passenger strand, and use 3–4 siRNA pools when appropriate.

What is custom siRNA synthesis?

Custom siRNA synthesis is the chemical production of sequence-specific small interfering RNA duplexes designed to trigger RNA interference and reduce target gene expression.

Can siRNA be used in vivo?

Yes. In vivo siRNA often requires chemical stabilization, low-endotoxin handling, and delivery strategies such as LNPs, GalNAc, lipid conjugates, peptides, or other targeting systems.

 

Explore TEW--> siRNA modification for in vivo delivery

What siRNA lengths and formats can you synthesize?

Common siRNA formats include 21-mers with 2-nucleotide 3′ overhangs, blunt 19-mers, and 25–27 nt Dicer-substrate siRNAs. Custom lengths can also be synthesized, including duplex, triplex, and self-annealed duplex formats.

What siRNA modifications and linkers are available?

Available options can include 2′-OMe, 2′-F, LNA/BNA, phosphorothioate linkages, terminal protection, PEG and AEEA linkers, cleavable linkers, fluorophores, affinity tags, and reactive handles such as amine, thiol, azide, alkyne, DBCO, BCN, and maleimide.

Do you deliver annealed duplexes?

Yes. Custom siRNAs can be delivered as annealed duplexes, single strands, triplex constructs, or self-annealed duplex designs depending on project requirements and downstream processing needs.

How should siRNA be stored?

Lyophilized siRNA is commonly stored at 4 °C short term or −20 °C long term. In solution, use RNase-free buffer, aliquot, and store at −20 °C to reduce freeze-thaw cycles.

What is the typical turnaround time?

Standard stabilized siRNAs may be completed in a few weeks after order confirmation. Heavily modified, conjugated, large-scale, or specialized QC projects may require additional time.

Can you make 100 g or larger siRNA batches?

Yes. Bio-Synthesis can support 100 g+ batch production for qualified siRNA programs, depending on sequence, chemistry, purification, QC, and project requirements.

What are the main benefits of siRNA technology?

siRNA technology enables specific and reversible knockdown of target gene expression, making it useful for functional genomics, drug target validation, pathway studies, and therapeutic oligonucleotide development.

Is siRNA immunostimulation a concern?

It can be, depending on sequence, model system, dose, and delivery method. Strategic 2′ modifications, especially 2′-OMe, and motif screening can help reduce TLR7/8-related innate immune activation.

What should I check if knockdown is low?

Verify the sequence, target transcript isoforms, delivery method, concentration, time point, cell health, and RNA handling. If needed, test multiple siRNA candidates or a pooled siRNA design.

More FAQ'sAll FAQ's

siRNA Design, Modification, and Application Guides

How to Design Effective siRNA (2026 Guide)

Key factors for siRNA design include target accessibility, GC content, seed region specificity, strand selection, and off-target minimization. Proper design improves knockdown efficiency and reproducibility.

siRNA Modification Strategies for In Vivo Delivery

Chemical modifications such as 2′-OMe, 2′-F, phosphorothioate linkages, and terminal protection improve stability, reduce immune activation, and enhance in vivo performance.

siRNA vs Antisense Oligonucleotides (ASO)

siRNA induces mRNA cleavage through RISC, while ASOs typically act via RNase H or steric blocking. Each approach has different applications in gene regulation and therapeutic development.

siRNA vs shRNA: Differences and Use Cases

siRNA provides transient gene silencing, while shRNA enables longer-term knockdown through vector-based expression systems. Selection depends on experimental design and duration requirements.

Common Mistakes in Gene Silencing Experiments

Frequent issues include poor sequence design, insufficient controls, off-target effects, improper delivery conditions, and lack of validation. Addressing these improves experimental success.

How to Order Custom siRNA

To request a custom siRNA quote, provide your target sequence, target gene, species, desired siRNA format, scale, purification method, modification needs, and delivery or conjugation requirements. If a final siRNA sequence is not available, our team can review the target region and recommend candidate designs.

Order Information to Provide

  1. Target information: target gene, species, accession number, target region, or candidate sequence.
  2. Format: 21-mer duplex, 19-mer blunt duplex, 25–27 nt Dicer-substrate siRNA, pooled siRNA, custom-length construct, triplex siRNA, self-annealed duplex, or single strands.
  3. Modifications: 2′-OMe, 2′-F, LNA/BNA, PS linkages, terminal protection, labels, linkers, reactive handles, or other specialty modifications.
  4. Delivery or conjugation: GalNAc, cholesterol/lipid, peptide/CPP, PEG, antibody, small molecule, polymer, or other bioconjugation strategy.
  5. Scale and grade: screening scale, mg scale, gram scale, 100 g+ batch production, RUO, in vivo grade, GLP-aligned, or cGMP support on request.
  6. QC requirements: MS, analytical HPLC, OD260, duplex integrity, endotoxin, RNase, Tm, functional testing, or custom documentation.

Design Support Available

If you need help selecting the best siRNA candidate, share your target sequence or gene information. Candidate review can consider:

  • Guide/passenger strand orientation
  • Seed region review at guide positions 2–8
  • GC content and homopolymer avoidance
  • Overhang selection such as UU or dT-dT
  • 5′ phosphate needs for guide-strand activity
  • Sense-strand deactivation strategy
  • Pooled siRNA strategy when multiple candidates are preferred
  • Modification placement for stability, specificity, and delivery
Request a Quote Ask for Design Support

Recommended Reading on Custom siRNA and RNA Interference

Key publications supporting siRNA mechanism, design principles, and chemical stabilization strategies.

  • Fire A, et al. “Potent and specific genetic interference by double-stranded RNA in C. elegans.” Nature (1998).
  • Elbashir SM, et al. “Duplexes of 21-nucleotide RNAs mediate RNA interference in mammalian cell culture.” Nature (2001).
  • Czauderna F, et al. “Structural variations and stabilizing modifications of synthetic siRNAs in mammalian cells.” Nucleic Acids Research (2003).
  • Allerson CR, et al. “Fully 2′-modified oligonucleotide duplexes with improved in vitro potency and stability.” J Med Chem (2005).
  • Krützfeldt J, et al. “Silencing of microRNAs in vivo with ‘antagomirs’.” Nature (2005).
  • Prakash TP, Bhat B. “2′-Modified oligonucleotides for antisense therapeutics.” Curr Top Med Chem (2007).
  • Nair JK, et al. “Multivalent N-acetylgalactosamine–conjugated siRNA for targeted delivery to hepatocytes.” J Am Chem Soc (2014).

Why Choose Bio-Synthesis

Trusted by biotech leaders worldwide for over 45+ years of delivering high quality, fast and scalable synthetic biology solutions.

Greetings Researchers,

Please be advised that any information, guidelines, writeups, and oral/video/graphic content on our website are intended solely as general guidelines.
It is the researcher's sole responsibility to conduct thorough research on the designs of the products intended for their experiments before submitting
their designs to Biosynthesis for review of production feasibility.
Thank you for your understanding.

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