siRNA | Thermo Fisher Scientific

High quality siRNA reagents for potent gene silencing

siRNA, or small interfering RNA, are double-stranded RNA molecules that play a role in the endogenous RNA interference (RNAi) pathway. RNAi using siRNA is the best way to effectively knock down gene expression to study protein function in a wide range of cell types.

Choose from guaranteed, pre-designed siRNAs targeting human, mouse, or rat
Validated siRNAs available against key human and mouse targets
Specificity-enhanced siRNA reduces the likelihood of off-target effects

Search pre-designed siRNA

Choose from our pre-designed siRNA product lines

	Silencer Select siRNA	Stealth RNAi siRNA	Silencer siRNA
	RECOMMENDED Highest knockdown, fewest off-targets	Good knockdown, reduced off-targets	Cost-effective, guaranteed siRNA
Potency (recommended working conc.)	5 nM	20 nM	50 nM
Silencing guarantee Learn more	2 of 2 siRNA	2 of 3 siRNA	2 of 3 siRNA
Target specificity	Highest	High	Moderate
Chemical modifications, length	LNA-modified 19-bp duplex 2 nt overhangs	Modified 25-bp duplex no overhangs	Unmodified 19-bp duplex 2 nt overhangs
Gene types targeted	Protein-coding genes Long non-coding RNA (lncRNA)	Protein-coding genes	Protein-coding genes
siRNA libraries	Custom gene lists Pre-defined collections, including the whole human genome	N/A	Custom gene lists Pre-defined collections
Target species	Human, mouse, rat (Other species: order custom designs)
Custom siRNA ordering tool	Custom Silencer Select siRNA	Custom Stealth RNAi siRNA	Custom Silencer siRNA

Libraries

siRNA libraries for high-throughput screening

Controls

Controls for RNAi experiments

In vivo RNAi

siRNA for in vivo use

New to siRNA? Complete the RNAi workflow with optimal siRNA delivery and tools for mRNA knockdown detection!

siRNA videos

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

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