siRNA, or small interfering RNA, are double-stranded RNA molecules that play a role in the endogenous RNA interference (RNAi) pathway. siRNA functions by stopping gene expression through binding to specific mRNA molecules and facilitating their degradation via the RNA-induced silencing complex (RISC), preventing protein production. This regulation is sequence-specific, allowing precise control over gene expression. Utilizing siRNA is an effective method to knock down gene expression and study protein function across various cell types and organisms.

High quality siRNA reagents

Selecting high-quality, validated siRNAs ensures effective and accurate gene silencing for research in gene function and regulation. We offer predesigned siRNA, backed by an industry leading guarantee, and custom synthetic siRNA solutions. All siRNAs are designed for optimal performance to help ensure robust and reproducible results.

Choose from our predesigned siRNA product lines

 Silencer Select siRNASilencer siRNAStealth RNAi siRNA
FeaturesRecommended: Higher knockdown, fewest off-targetsCost-effective, guaranteed siRNAGood knockdown, reduced off-targets
Potency (recommended working conc.)5 nM50 nM20 nM
Silencing guarantee2 of 2 siRNA2 of 3 siRNA2 of 3 siRNA
Target specificityHighestModerateHigh
Chemical modifications, length
  • LNA-modified
  • 19-bp duplex
  • 2 nt overhangs
  • Unmodified
  • 19-bp duplex
  • 2 nt overhangs
  • Modified
  • 25-bp duplex
  • No overhangs
Gene types targetedProtein-coding genesProtein-coding genes
siRNA librariesN/A
Target speciesHuman, mouse, rat (for other species, order custom designs)
Custom siRNA ordering toolCustom Silencer Select siRNACustom Silencer siRNACustom Stealth RNAi siRNA
schematic representing 3 steps in siRNA workflow


Predesigned siRNAs: How much do I need?

Number of transfections from 5 nmol of siRNA
Plate type (Transfection volume)10 nM final siRNA concentration100 nM final siRNA concentration
6 well (2.5 mL)20020
12 well (1 mL)50050
24 well (0.5 mL)10010
96 well (0.1 mL)5,00050
Questions?

Technical inquires:
Our Technical Application Scientists are available to help assist you at techsupport@thermofisher.com

Ordering & Order Status inquires:
If you have questions about pre-designed RNAi orders and order status, please contact us at genomicorders@thermofisher.com

If you have any questions about Custom RNAi orders and order status, please contact us at RNAiSupport@thermofisher.com

For Research Use Only. Not for use in diagnostic procedures.

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