Purine enzyme activities are usually assayed by radiochemical procedures and often TLC is part of the separation method. In screening patients with rheumatic diseases, these procedures have shown disadvantages like a relatively large coefficient of variation (C.V.) and time-instability. We describe a non-radiochemical reversed-phase HPLC micro-method with UV detection for measurement of activit...

1. A synthetic 3-([14C]valine)-labelled tetradecapeptide renin substrate was used to measure renin concentration. Renin liberated "4C-labelled angiotensin I, which was separated from the labelled substrate by paper chromatography. The conversion ofsubstrate into angiotensin I was quantitated by liquid-scintillation counting of radioactivity. 2. The rate of conversion of the substrate into angio...

Tera Becquerel quantities of a number of radioisotopes such as 131I, 99Mo, 32P, 153Sm, 51Cr, 82Br, 203Hg, 140La, 46Sc, etc. are produced in various radiochemical forms and regularly supplied through Board of Radiation & Isotope Technology (BRIT) for applications in medicine, industry, biology, agriculture and research & development activities. These radioisotopes are produced by neutron activat...