In mammalian cells the introduction of small 21–23 nucleotide sequence-specific RNA duplexes (small/short interfering RNAs, siRNAs) can act to initiate post-transcriptional gene knockdown and avoid triggering non-specific effects in mammalian cells (Figure 1).  BLOCK-iT siRNAs are traditional, unmodified siRNA duplexes synthesized on demand with the highest quality. Using our award-winning BLOCK-iT RNAi Designer, you can design Custom BLOCK-iT siRNA sequences for any organism, using a cDNA sequence or a GenBank® accession number.

Custom BLOCK-iT siRNAs provide:

  • The ability to custom design any number of siRNAs and controls
  • High-quality, error-free siRNA duplexes
  • A cost-effective approach for RNAi experiments

Figure 1. Typical siRNA duplex:  21 nucleotides long, with 2 DNA base-pair overhangs (TT).

Ordering information

For your convenience BLOCK-iT siRNAs can be ordered in 4 different synthesis scales. To design and order BLOCK-iT siRNAs, please visit the BLOCK-iT RNAi Designer.


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