Synthesis, characterization and in vivo evaluation of [(62)Zn]-benzo-δ-sultam complex as a possible pet imaging agent

Ann Nucl Med. 2014 Nov;28(9):880-90. doi: 10.1007/s12149-014-0885-y. Epub 2014 Jul 15.

Abstract

Objective: The development of a new tracer based on the cyclic sulfonamides (sultams) was investigated.

Methods: 3-(Methoxy-phenyl-methyl)-1,6-dimethyl-1H benzo[c][1,2] thiazine 2,2-dioxide (benzo-δ-sultam) was synthesized and characterized by elemental analysis, FT-IR spectroscopy and single crystal X-ray structure determination. The prepared cyclic sulfonamide was labeled with non-commercial (62)Zn radioisotope for fast in vivo targeting and Coincidence imaging purposes (radiochemical purity 97 % ITLC, 96 % HPLC, specific activity 20-23 GBq/mmol). In vivo biodistribution of the final complex was investigated in Sprague Dawley(®) rats bearing fibro sarcoma tumor after 2, 4 and 8 h post injection and compared with free Zn(+2) cation.

Results: Using instant paper chromatography method, the physicochemical properties of labeled compounds were found sufficiently stable in organic phases, e.g. a human serum, to be reliably used in bioapplications.

Conclusions: The complex exhibited a rapid as well as high tumor uptake (tumor to blood ratio 4.38 and tumor to muscle ratio 9.63) resulting in an efficient tumor targeting agent.

Publication types

  • Evaluation Study

MeSH terms

  • Animals
  • Chromatography, High Pressure Liquid
  • Chromatography, Paper
  • Humans
  • Molecular Structure
  • Naphthalenesulfonates* / chemical synthesis
  • Naphthalenesulfonates* / chemistry
  • Naphthalenesulfonates* / pharmacokinetics
  • Neoplasms, Experimental / diagnostic imaging
  • Positron-Emission Tomography / instrumentation
  • Positron-Emission Tomography / methods*
  • Radiopharmaceuticals* / chemical synthesis
  • Radiopharmaceuticals* / chemistry
  • Radiopharmaceuticals* / pharmacokinetics
  • Rats, Sprague-Dawley
  • Sarcoma / diagnostic imaging
  • Serum / chemistry
  • Spectroscopy, Fourier Transform Infrared
  • Zinc Radioisotopes* / chemistry
  • Zinc Radioisotopes* / pharmacokinetics

Substances

  • Naphthalenesulfonates
  • Radiopharmaceuticals
  • Zinc Radioisotopes
  • naphthosultone