• banner:siRNA scientific innovation in siRNA design and novel modification strategies  

    Small Interfering RNA (siRNA)

    Dharmacon siRNA products are the result of scientific innovation in siRNA design and novel modification strategies to optimize potency, specificity and delivery.


    siRNA design

    Our scientists were the first to establish siRNA design rules for high potency silencing and continue to drive innovation in this area. The SMARTselection algorithm selects highly functional and specific siRNAs for all of our predesigned products, enabling us to offer a functionality guarantee for all three of our major product lines: ON-TARGETplus, siGENOME, and Accell reagents.

    SMARTpool technology

    Pooling of siRNAs better mimics the natural RNAi pathway, and when combined with SMARTselection design, provides advantages for both potency and specificity.

    • Targeting four mRNA regions at once improves the likelihood of effective silencing and reduces false negatives due to inaccessible binding sites
    • Lower relative concentration of each siRNA reduces sequence-specific off-targeting
    • All Dharmacon predesigned siRNA products are all available as SMARTpool reagents or up to 4 individual siRNAs

    Reducing off-targets for better specificity

    The primary source of siRNA-mediated off targets is the seed region (nucleotides 2-7) which uses the microRNA pathway to induce non-specific gene silencing via interactions within the 3' UTR. Seed region filters and seed frequency analysis are incorporated in the SMARTselection siRNA design strategy to reduce microRNA-like off-target activity. Dharmacon siRNA products provide the most comprehensive bioinformatic strategies to mitigate off-targeting.

    • Conserved microRNA seed regions are filtered out of siRNA designs
    • Frequency analysis of siRNA seed complements (how often this occurs in the 3' UTR transcriptome) are performed and preference is given to siRNA designs with low-frequency seeds
    • ON-TARGETplus siRNA

      Enjoy optimal specificity from the only siRNA with a patented modification pattern to reduce off-targets caused by either the sense or the antisense strand.

    • Accell siRNA

      Specially modified for delivery into difficult-to-transfect cells without a transfection reagent, Accell enables non-viral RNAi in neuronal, immune, and stem cells.

    • siGENOME siRNA

      Highly potent siRNA for all human, mouse, and rat genes. siGENOME has provided the longest standing siRNA silencing guarantee on the market.

    • Lincode siRNA

      siRNAs for efficient knockdown of long, noncoding RNA (lncRNA) genes with modifications to ensure specificity.

    • Custom siRNA Synthesis

      No pre-designed product to fit your needs? Use our online design tools and extensive synthesis options to create a custom siRNA specific for your application.

    • ON-TARGETplus Controls

      Validated positive controls and non-targeting negative controls utilizing patented modifications for optimal specificity. Available as pools or single siRNAs.

    • Accell Controls

      Effectively optimize Accell siRNA delivery conditions with fluorescent or unlabeled positive and negative controls. Kits of validated controls available.

    • siGENOME Controls

      A robust selection of validated positive, negative, and novel RISC-Free® controls to effectively assess all aspects of RNAi experiments.

    • Lincode Controls

      Endogenous lncRNA positive control and non-targeting control siRNA and pool reagents for high-confidence experiments.

    • Human siRNA Libraries

      Find the predefined gene family, including Druggable genes or Whole Genome, that’s right for your discovery efforts.

    • Mouse siRNA Libraries

      A wide selection of predefined siRNA libraries, including the most up-to-date Whole Mouse genome collection available.

    • RTF siRNA Libraries

      Human and mouse SMARTpool siRNA libraries in a novel pre-dispensed format to enable RNAi screening without the need for high-throughput automation.

    • Lincode siRNA Libraries

      Choose a collection of Human or Mouse siRNAs based on RefSeq lncRNA genes with NR_ Accession numbers.

    • Cherry-pick Libraries

      Fast and easy online configuration and ordering of plated siRNA & microRNA reagents targeting your genes of interest.

    • Zoonome Custom siRNA Libraries

      Enzymatically generated custom siRNA libraries for screening in non-human or mouse model organisms.


    Product Line Selection

    Which siRNA is right for you?

    Dharmacon offers four complete pre-designed product lines across human, mouse and rat genomes. Use the table below to assist you in determining the right siRNA product line for your needs.

      Cost-effective, efficient silencing High specificity for reduced off-targets + efficient silencing Highly specific knockdown of long noncoding RNA (lncRNA) Target silencing in difficult-to-transfect cells
      siGENOME siRNA ON‑TARGETplus siRNA Lincode siRNA Accell siRNA
    Pre-designed for Human, Mouse and Rat protein-coding genes + +   +
    Pre-designed for Human and Mouse long noncoding RNA (lncRNA)     +  
    Recommended for transfectable mammalian cells in culture + + +  
    Recommended for neuronal, suspension, primary and other difficult-to-transfect cells       +
    Recommended transfection reagent DharmaFECT transfection reagent DharmaFECT transfection reagent DharmaFECT transfection reagent None required
    Available as SMARTpool reagent + + + +
    Available as four individual siRNAs + + + +
    Guaranteed knockdown by SMARTpool and 3 of 4 siRNAs + +    
    Sense strand is modified to prevent interaction with RISC and favor antisense strand uptake Selective application when thermodynamic analysis indicates it necessary for favorable antisense RISC loading + + +
    Antisense strand seed region is modified to destabilize off-target activity and enhance target specificity   + +  
    Modifications to facilitate cellular uptake without separate transfection reagents       +
    Stabilizing modifications to prevent nuclease-mediated degradation       +
    Sequence information provided with purchase + + + +

    siRNA Resources