Abstract
NBNPQD (2-benzyl-1-oxo-1,2-dihydropyrido[4,3-b]quinoxaline 5,10-dioxide) is a new synthesized quinoxaline derivative. It could be labeled with auger emitter I-125 successfully with yield about 90 %. The labeled product was evaluated by electrophoresis and thin layer chromatography. Factors affected labeling yield were studied. I-125-NBNPQD was stable up to 48 h post labeling. Biodistribution study of I-125-NBPQD in normal and tumor bearing mice was also conducted. The biodistribution data revealed that I-125-NBNPQD diffused rapidly to tumor sites in both ascites and solid tumor bearing mice. I-125-NBNPQD was declined rapidly from most of organs but slowly from tumor sites. In vitro radiotoxicity of I-125-NBNPQD increased with the increase of its radioactivity. This study encourages the possible use of I-125-NBNPQD in tumor imaging and treatment. It also encourages further studies on the chemotherapeutic activity of NBNPQD hoping to get a new potent antitumor agent.