NEW Silencer® Select In Vivo Ready siRNAs
NEW Silencer® Select siRNAs, HPLC Purified

More Options for Your RNAi Research: In Vivo Ready Silencer® Select siRNAs

Applied Biosystems continues to expand the range of Silencer® Select siRNAs to accommodate researchers’ needs. Silencer Select In Vivo Ready siRNAs are optimized for use in animals. In addition, larger sizes of HPLC-purified siRNAs are available for applications requiring modified or larger amounts of siRNAs.

Advantages of Silencer Select siRNAs
Silencer Select siRNAs incorporate the latest improvements in siRNA design, prediction algorithms for off-target effects, and chemical modifications to yield siRNAs with unrivalled knockdown consistency, potency, and specificity. The result is more successful experiments and cleaner, more consistent phenotypic data.

New Design Algorithm Improves Effective siRNA Prediction Accuracy
Silencer Select siRNAs are designed with a new algorithm that incorporates over 90 sequence and thermodynamic parameters. Rigorous testing of siRNAs designed with this algorithm has shown its ability to predict siRNAs that can knock down target mRNA levels by 70% or better, 94% of the time [1]. More importantly, 87% of the siRNAs tested silenced their targets by 80% or better. This represents a 28% increase in predictive accuracy at the 80% knockdown level over the previous generation siRNA design algorithm.

Up to 100-Fold More Potent than Current siRNA Technologies
Silencer Select siRNAs are so potent that, for easily transfected cells, such as HeLa cells, only 3–5 nM final concentration is recommended for routine use. This represents a 10- to 20-fold lower concentration range than most suppliers currently recommend. Lower siRNA concentrations significantly reduce off-target effects and decrease reagent costs per experiment. Data show that Silencer Select siRNAs are 5- to 100-fold more potent than siRNAs—both modified and unmodified—from other suppliers (Figure 1).

Figure 1. Silencer® Select siRNAs Provide Up to 100X Higher Potency Compared to Competing siRNAs. Each data point represents a minimum of 30 siRNAs to 10 gene targets, tested in triplicate. Each siRNA was individually transfected into HeLa cells at the indicated siRNA concentration. After transfection (48 hr), RNA was isolated using the MagMAX™-96 Total RNA Isolation Kit, cDNA was synthesized using the High Capacity cDNA Reverse Transcription Kit, and real-time PCR was performed using TaqMan® Gene Expression Assays. Results are expressed as percent of mRNA remaining as compared to Silencer Negative Control #1 siRNA transfected cells, using 18S as the normalizing gene.

Novel Chemical Modifications Reduce Off-Target Effects by Up to 90%
Although siRNA design and bioinformatic filters can significantly improve siRNA specificity, further improvements can be made with carefully selected chemical modifications. Silencer Select siRNAs incorporate a novel set of chemical modifications that reduce off-target effects by up to 90% without compromising siRNA efficacy or potency [1].

Now Available for Expanded Applications

In Vivo Ready for Animal Injection
For siRNA-induced gene silencing experiments in animals, high quality siRNA is critical. Applied Biosystems Silencer Select In Vivo Ready siRNAs—the highest quality siRNAs available—provide the extra level of purification and testing required for introduction into animals. Each siRNA strand is individually purified by HPLC, desalted, and annealed with its complementary strand. In Vivo Ready siRNAs are then further purified to remove excess salt. The result is a highly pure siRNA with minimal salt content, suitable for in vivo applications. In Vivo Ready siRNAs contain <0.6 mM Na+, <2.0 mM K+, and <0.1 mM Mg2+ when resuspended at a concentration of 50 μM in de-ionized water. In Vivo Ready siRNAs are then filtered through a 0.2 μm pre-sterilized filter and tested for the presence of endotoxin.

These siRNAs, once resuspended in the appropriate buffer or formulated as you desire, are ready for delivery into animals. Silencer Select In Vivo Ready siRNAs are synthesized from a sequence you provide or from Silencer Select Pre-designed or Validated siRNA sequences.

HPLC Purified—New Larger Size
To meet the needs of customers performing applications that require larger amounts of siRNAs or modified siRNAs, HPLC purified Silencer Select siRNAs are now also available in a 250 nmol size. HPLC-purified siRNA strands are analyzed by MALDI-TOF mass spectrometry and analytical HPLC. The efficiency of annealing is verified by PAGE. Silencer Select HPLC-Purified siRNAs are synthesized from a sequence you provide or from Silencer Select Pre-designed or Validated siRNA sequences.