Determination of alpha-fetoprotein by radioimmunoassay. Improvement of the quality of a locally produced kit.

With the aim of improving the sensitivity and simplifying the analytical procedure, changes have been made in the test for determining alpha-fetoprotein (AFP) by radioimmunoassay, using a locally developed kit first produced about ten years ago. Close correlation between values obtained for serum AFP using the old and new procedures was obtained (r = 0.977), but the mean value for healthy nonpregnant adults was found to be 2.5 micrograms AFP/l with the new test. This is about half the level obtained earlier and confirms the recent findings of other authors. Besides reducing the time and equipment necessary for performing the test, the modified procedure enables more precise distinction between normal and elevated concentrations of AFP in patient serum.