title: Preparation and evaluation of a ⁹⁹mTcN-PNP complex of sanazole analogue for detecting tumor hypoxia.
abstract: A sanazole derivative, having a favorable single electron reduction potential (SERP) value compared to that of misonidazole, was synthesized and radiolabeled with [(99m)TcN(PNP)] precursor to evaluate its potential as a hypoxia imaging agent. The complex, which was lipophilic, could be prepared in good yields and challenging studies with cysteine showed stability of the complex against trans-chelation. However, despite being lipophilic as well as possessing favorable SERP value, biodistribution studies of this complex in fibrosarcoma tumor bearing Swiss mice showed low uptake in tumor. This observation is possibly attributed to fast clearance of the complex from blood, whereby the complex spends insufficient time in tumor to get reduced and trapped. Though uptake in tumor was low, slow clearance of activity from tumor suggests reduction and trapping of the complex in hypoxic cells. The present (99m)Tc-complex demonstrated acceptable values of tumor to blood (TBR) and tumor to muscle (TMR) ratios. However, low uptake in tumor which may not be indicative of the actual hypoxic status of the tumor, limit the utility of the complex to detect tumor hypoxia.
authors: Radiopharmaceuticals Program, Board of Radiation and Isotope Technology, Mumbai 400705, India.
authors: Anupam
authors: A
authors: Mathur
authors: Madhava B
authors: MB
authors: Mallia
authors: Sharmila
authors: S
authors: Banerjee
authors: H D
authors: HD
authors: Sarma
authors: M R A
authors: MR
authors: Pillai
mesh_terms: D000818:Animals; D015687:Cell Hypoxia / Q000502:physiology; D005354:Fibrosarcoma / Q000000981:diagnostic imaging* / Q000378:metabolism*; D051379:Mice; D015609:Organotechnetium Compounds / Q000138:chemical synthesis / Q000737:chemistry* / Q000493:pharmacokinetics; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000138:chemical synthesis / Q000737:chemistry* / Q000493:pharmacokinetics; D014230:Triazoles / Q000138:chemical synthesis / Q000737:chemistry* / Q000493:pharmacokinetics
chemical_list: D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D014230:Triazoles; C072690:AK 2123