What is in the HiSpec Buffer that selectively synthesizes cDNA from mature miRNAs ONLY?

The proprietary, patent-pending formulation selectively prohibits the reverse transcription of longer RNAs from being reverse transcribed. Using HiSpec Buffer, cDNA can be efficiently synthesized from RNA molecules ranging up to 100 bp. Mature miRNAs are < 25 bp, while some precursor miRNAs are longer than 100 bp. As a result, HiSpec Buffer is ONLY recommended for mature miRNAs.