Silencer Select siRNAs from Ambion
  • Incorporate the latest improvements in siRNA design, off-target effect prediction algorithms, and chemistry
  • Provide unrivalled silencing consistency, potency, and specificity
  • Result in fewer failed experiments due to poor silencing
  • Yield cleaner, more consistent phenotypic data

100% Guarantee – The BEST in the Industry

At Thermo Fisher Scientific, we guarantee that when you purchase two Invitrogen Silencer Select Pre-designed siRNA to the same target, then those two siRNAs will silence the target mRNA by 70% or more. To qualify for the guarantee, siRNA's must have been transfected at ≥5 nM and mRNA levels detected 48h post transfection. Real-Time RT-PCR is recommended but not required for this application. Customers must also show > 80% knockdown with a positive control siRNA to demonstrate transfection efficiency. If the guaranteed level of knockdown is not observed and an appropriate positive control is successful, a onetime replacement of up to two new Silencer Select siRNA designs will be provided free of charge. This guarantee does not extend to any replacement product.

Reducing false positives and false negatives in siRNA experiments
(Open access to Ambion siRNA sequences and associated data)

In recent years, siRNA screens have highlighted issues with the technology stemming from off target effects, variable level of knockdown efficacy, and low-level confidence in hits from screening campaigns.

A recent genome-wide screen published in Nature by researchers at the National Institutes of Health highlights an effective approach to circumvent the challenges currently being faced by the screening community. New bioinformatics techniques to decipher real positives from false positives that arise from the seed region have been highlighted in this publication. Seed sequence driven off target effects have been extensively observed in siRNAs screens as these stem from the miRNA driven seed sequence. This seminal work highlights usage of high potency Silencer Select siRNA at lower siRNA concentration as arrayed singles allowing identification of off targets (false positive or false negative) stemming from the seed sequence. Such deconvolution is not possible for a pooled approach where unique biology can be observed owing to two or more siRNAs working in a concerted manner.

National Center for Advancing Translational Sciences (NCATS) and Thermo Fisher Scientific are also providing all researchers access to siRNA sequences and associated data on PubChem from  Silencer Select siRNA library, which includes 65,000 siRNA sequences targeting more than 20,000 human genes.

Get the siRNA sequences here

PRODUCT REPLACEMENT AS SET FORTH ABOVE IS THERMO FISHER SCIENTIFIC'S SOLE OBLIGATION AND CUSTOMER’S SOLE AND EXCLUSIVE REMEDY WITH RESPECT TO THE GUARANTEE GIVEN ABOVE. To arrange a replacement, contact Technical Services. Please be ready to supply data indicating transfection efficiency and measurement of mRNA knockdown. Contact Technical Support if you require such a replacement.