RNA interference (RNAi) is the best way to effectively knock down gene expression to study protein function in a wide range of cell types. Traditional RNAi methods for gene knockdown in mammalian cells involved the use of synthetic RNA duplexes consisting of two unmodified 21-mer oligonucleotides annealed together to form short/small interfering RNAs (siRNAs). Silencer® Select siRNA and Stealth RNAi™ siRNA improve upon these traditional duplexes by using proprietary chemical modifications to ensure better RNAi results.

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

Finding the Right Ambion siRNA

Search the more than 200,000 Ambion® siRNAs using our siRNA Selection Tool.

Which siRNA is right for you?

  Cost-effective siRNA Good knock-down, low off-target Highest knock-down, lowest off-target
Potency100 nM
recommended conc.
20 nM
recommended conc.
5 nM
recommended conc.
Learn more
2 of 3 siRNA guaranteed2 of 3 siRNA guaranteed2 of 2 siRNA guaranteed
Target specificityModerateHighHighest
Innate immune responseLowMinimized through chemical modificationsMinimized through chemical modifications
Molecular formatUnmodified 21-bp duplex with overhangsModified 25-bp duplex with no overhangsLNA modified 21-bp duplex with overhangs
CoverageCoding RNACoding RNACoding & non-coding RNA
Target speciesHuman, mouse, rat
(Other species: use custom tool)
Human, mouse, rat
(Other species: use custom tool)
Human, mouse, rat
(Other species: use custom tool)
Custom toolCustom Silencer® siRNACustom Stealth RNAi™ siRNACustom Silencer® Select siRNA
Cat. No.
AM16708: Silencer® Pre-designed siIRNA 5 nmol1299003: RNA-Stealth Oligos Tube Set4392420: Silencer® Select Pre-Designed siRNA 5 nmol
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siRNA selection tool

siRNA videos

Meet the Inventor: Silencer® Select siRNA technology

Meet the inventor: Susan Magdaleno discusses Silencer® Select siRNA technology

Dr. Gavin Robertson describes how Silencer® Select siRNA technology is advancing melanoma research.

Lipofectamine® RNAiMAX reagent


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