Human growth hormone in urine: development of an ultrasensitive radiometric assay

Abstract
Summary An immunoradiometric assay for human growth hormone (HGH) has been developed which has a detection limit of 1ng/l and can measure HGH in unextracted urine from normal children and adults. The assay is based on a two-step procedure, using a solid-phase goat-anti-HGH immunosorbent for immunoextraction and [125I]-labeled monoclonal HGH-antibody for detection and quantification. The assay is not affected by urea, NaCl or changes of pH from 5–8. The mean urine HGH concentration in normal children is 6.78±7.6 (SD) pg/ml, in patients with HGH-deficiency 1.3±0.9 pg/ml which increases to 11.7±13.4 pg/ml on the day of growth hormone injection.