Abstract
Synthesis of zinc O, O-diisobutyldithio [35S] phosphate (ZDDP [35S]) was successfully carried out, using an exchange reaction between ammonium salt of O, O-diisobutyl-dithiophosphoric acid and elementary sulfur [35S]. The experimental tehnique and apparatus in this method are much simpler, therefore much safer, than the ordinary synthetic method where P235S5 is used. The ZDDP [35S] obtained was both chemically and radiochemically pure. The specific activity of the sulfur in ZDDP [35S] was 20.6% of that of the elementary sulfur [35S] used. According to this synthetic method, a satisfactorily high specific activity of ZDDP [35S], can be easily obtained.
