Silica-based nucleic acid purification methods employ a simple bind-wash-elute process. Nucleic acids bind to the silica membrane in the presence of chaotropic salts. Polysaccharides and proteins do not bind well to the column and residual traces are removed during alcohol-based wash steps, along with the salts. After binding and washing, nucleic acids are selectively eluted under low-salt conditions, using water or TE buffer. Silica-based methods are fast, easy-to-perform and economical.