miRNA molecules are small, single-stranded RNA molecules that are between 19 and 30 nucleotides in length and help regulate protein production by binding to the messenger RNA (mRNA) that encode which proteins the ribosome should produce. There has been a recent groundswell of interest in the processes in which these molecules are active, but the purification of the samples has oftentimes been laborious and complicated. According to the company, the new mirPremier kit provides researchers with at tool that enables "50 per cent faster miRNA preparation with no detectable large RNA". The kit continues Sigma-Aldrich's push into the RNAi field, following the recent launches of its Mission LentiExpress system for delivering shRNA short hairpin RNA) using lentivirus vectors and the N-TER nanoparticle siRNA (small interfering RNA) delivery system. The miRNA field is relatively new with the discovery of the first miRNAs having been made in 1993; however the term miRNA was not coined until 2001. Since then nearly 500 human miRNA molecules have been identified and they have been found to play a role in regulating nearly 30 per cent of human genes either 'silencing' the mRNA or flagging them for early degradation. miRNA misfunction has been implicated in the progression of various diseases such as cancer, heart disease and Parkinson's with recent research showing that there are three miRNA molecules that play a key role in the p53 tumour suppressor network. Many laboratory suppliers have been launching products to enable miRNA analysis with Illumina, Applied Biosystems and Agilent having all launched arrays this year. In addition, IDT launched a miRNA kit, dubbed the miRCAT, to enable researchers to discover new miRNA sequences using sequencing techniques. The new mirPremier system enables the purification of miRNA from a diverse range of biological samples such as mammalian cell cultures, animal tissue, and microbial cultures in less than 30 minutes. This rapid extraction of miRNA has been heralded as "critical for downstream applications" by Dr David Smoller, president of Sigma-Aldrich Research Biotech Business Unit. "Isolation of miRNA and other small RNAs using the mirPremier microRNA Isolation Kit yields a highly pure and concentrated sample, using a simplified and streamlined protocol without the need of hazardous organic solvents such as phenol and chloroform," said Tim Fleming, director for Global Life Science Commercial Marketing for Sigma-Aldrich. "Unlike other miRNA purification methods, mirPremier provided highly purified miRNA samples with no detectable large RNA."