A new one-step method for the preparation of polyacrylamide gels containing tritium and carbon-14 for liquid scintillation counting is presented. Forty-four hours after placing the gel slices in the scintillation fluid described in the text, the samples are ready for counting. This one-step method is compared to the method of D. Goodman and H. Martzura (1971, Anal. Biochem. 42, 481) and is shown not only to require fewer manipulations but also to eliminate the need for a heating oven and to reduce the reagent costs. © 1979.