Metabolic comparison of radiolabeled aniline- and phenol-phthaleins with ¹³¹I

The metabolic comparison of aniline- and phenol-phthaleins radiolabeled with ¹³¹I (¹³¹I-APH and ¹³¹I-PPH, respectively) has been investigated in this study. To compare the metabolic behavior of these phthaleins and their glucuronide conjugates radiolabeled with ¹³¹I, scintigraphic and biodistributional techniques were applied using male Albino rabbits. The results obtained have shown that these compounds were successfully radioiodinated with a radioiodination yield of about 100%. Maximum uptakes of ¹³¹I-APH and ¹³¹I-PPH, which were metabolized as N- and O-glucuronides, were observed within 2 h in the bladder and in the small intestine, respectively. In the case of verification of considerably up taking of these compounds also by tumors developed in the small intestine and in the bladder tissues, these results can be expected to be encouraging to test these compounds, which will be radiolabeled with other radioiodines such as ¹²⁵I, ¹²³I and ¹²⁴I as imaging and therapeutic agents in nuclear medical applications