Expedite gene function analysis with libraries of effective siRNAs
Increasingly, researchers are harnessing the power of RNAi to better understand gene function. To support this growing demand, Thermo Fisher Scientific has developed pre-defined and custom sets of premium-quality Ambion™ siRNAs—Silencer™ and Silencer™ Select siRNA Libraries—for performing RNAi experiments in human, mouse, and rat cell systems.

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NEW Silencer Select Libraries   NEW Silencer Libraries

Rigorous quality control for results you can trust 


Thermo Fisher Scientific synthesizes all siRNAs in-house to exacting quality standards. After synthesis using extensively validated and controlled procedures, each RNA oligonucleotide is assessed by MALDI-TOF (matrix-assisted laser desorption ionization—time-of-flight) mass spectrometry to confirm siRNA identity and quality. After annealing, each siRNA duplex is analyzed by nondenaturing gel electrophoresis to confirm proper annealing. And to follow each Ambion siRNA from order to delivery, we use a proprietary, state-of-the-art electronic tracking system. The result is premium-quality siRNA you can trust.

Information to accelerate discovery 


All Silencer and Silencer  Select siRNA Libraries, whether pre-defined or custom-made, are supplied with full siRNA sequence information and, when available, with siRNA validation data. Also provided on the CD accompanying the siRNA library are gene annotation information, which includes gene symbol, gene name, aliases, NCBI Entrez Gene ID, associated RefSeq mRNA accession numbers, and other accession numbers. Plates are individually barcoded with unique identifiers; this information is also provided with the siRNA and gene information.

To create these siRNA libraries, the bioinformatics team uses PANTHER (www.pantherdb.org) and Gene Ontology™ annotation information to create up-to-date target gene sets. siRNAs targeting the collection are then plated to order (minimum 1 nmol), giving you not only the most up-to-date siRNA libraries but also the freedom to customize your library so that it is most convenient for your particular experimental setup. Want to add siRNAs to your collection? No problem! We can also provide siRNAs in 96-well or 384-well plates, deliver multiple aliquots of each plate, arrange siRNAs in custom configurations, and provide siRNAs individually and/or in pools.