Tris-CAPS (N-cyclohexyl-3-aminopropanesulfonic acid) buffer has a concentration of 10X and a pH level of 9.6. It contains 0.6 M Tris and 0.4 M CAPS and is stored at room temperature. Tris-CAPS buffer is used in semi-dry Western blotting systems to increase transfer efficiency. The methanol in the anode buffer (pH 9.6) helps the protein stick to the membrane due to an increase in nonpolar binding. The SDS in the cathode buffer (pH 9.5) helps to ensure that all proteins are negatively charged and that larger proteins transfer out of the gel.