The ReliaPrep RNA Cell Miniprep System provides a fast and simple technique for preparation of intact total RNA from cultured cells or tissue in as little as 30 minutes. The proprietary column/binding matrix can efficiently capture RNA from very small amounts of input material, isolating RNA eluted in a minimal volume (less than 15ul). Using this membrane-based purification system, from 100 to 5 x 10(6) cultured cells or 0.25 to 20mg of tissue can be processed per purification. The system incorporates a DNase treatment step directly on the minicolumn membrane and effectively removes substances that can inhibit downstream assays. Purification is achieved without the use of phenol:chloroform extractions or ethanol precipitations, resulting in pure RNA that does not require additional purification or concentration of the RNA for use in demanding applications.