A simple and rapid procedure for the preparation of human LDH-1 and LDH-5 using an ion-exchange mini-column

A simple and rapid preparation of LDH-1 and LDH-5 from heart and liver homogenates is described. The preparation is carried out on a 3 ml mini-column of DEAE-Sephadex A-50. The fractions of heart homogenate containing LDH-1 were eluted with an NaCl gradient after salt elution of other isoenzymes. This semi-purified fraction was re-applied to a second column and the whole cycle was repeated. This procedure takes less than 90 min to complete and a 70% yield of LDH-1 can be obtained. The fractions of liver homogenate containing LDH-5 were eluted by simple washing of the gel column with Tris-HCl buffer. The semi-purified fraction was re-applied to a second column and the wash procedure was repeated. This preparation took less than 30 min to complete and a 70% yield was obtained. No apparatus other than a small mini-column is required for this purification.