The GRS FullSample Purification Kit provides an efficient and fast method for the simultaneous purification of genomic DNA, total RNA (including miRNA), and total protein from whole blood and other biological fluids, animal tissues, and cultured cells. DNA is bound to a DNA binding spin column and the flow-through is subsequently passed through a RNA binding spin column. The proteins in the flow-through can then be precipitated with acetone. Contaminants are washed and DNA is eluted with a low salt buffer and RNA is eluted with RNAse-free water. The entire procedure can be completed in less than half an hour without phenol/chloroform or alcohol precipitation. Eluted gDNA (20-30kb) is suitable for most common downstream applications, including PCR, whereas purified total RNA (including microRNA) is ready to use for RT-PCR, primer extension, and Northern Blotting. After protein precipitation, the pellet is washed with ice-cold ethanol and resuspended in an appropriate volume of desired buffer compatible with the downstream application of choice.