GenScript now provides reliable long RNA oligos up to 160 bases to meet even more research application needs. To ensure that the RNA oligos are of highest quality, all RNA oligonucleotides are identified by electrospray ionization-mass spectrometry (ESI-MS) and purified by RNase-free HPLC. To meet quality control specifications, the deviation from measured mass to calculated mass must be no more than 1‰ and the purity of the RNA must be more than 90%.