Use of activated charcoal in the radioimmunoassay of human growth hormone in plasma.

The use of activated charcoal in the radioimmunoassay of human growth hormone is described. The method permits the rapid separation of bound from free labelled human growth hormone in large batches and affords a quick method for screening iodination eluates. The necessity for an equality of protein concentration for the incubation and the separation procedure is emphasized. The method is simple, reliable and rapid, and the sensitivity obtained compares favourably with that of other methods of separation.