Preparative-scale purification of RNA using an efficient method which combines gel electrophoresis and column chromatography

Here we describe a reliable method for purifying large amounts of RNA of any sequence and length with comparable efficiency and resolution of gel electrophoresis and with capacity approaching that of column chromatography. The RNA mixture of interest is separated on a cylindrical denaturing polyacrylamide gel, eluted by a peristaltic pump, detected by a UV-vis detector, and collected by a fraction collector. Using this method, we were able to separate one third of a 100 ml in vitro transcribed 34mer hammerhead ribozyme (~6.2 mg) in a single run. The entire 100 ml transcribed RNA (~18.5 mg) was separated after consecutive runs using one single gel preparation.