Synthesis, optimization and biological evaluation of [99m]Tc-digoxin as possible cardiac imaging agent

Heart imaging radiopharmaceuticals could improve the diagnostic value of routine heart scanning for detecting cardiac disorders. The aim of the study was to prepare high radiochemical purity [99m]Tc-Digoxin in a yield of about 98%. The optimal conditions for labelling were as follows: 100microg of Digoxin, 2microg of SnCl2·2H2O, room temperature [25 +/- 1°C], reaction retention time of 30 min at pH 7. Under these conditions, the radiochemical yield of [99m]Tc-Digoxin reaches 98%. In vivo bio distribution was performed in normal Swiss Albino mice at different time intervals after administration of [99m]Tc-Digoxin.Scintigraphic study of [99m]Tc-Digoxin was performed in rabbits. The heart uptake of 99m Tc-Digoxin was sufficiently high and thus may be a potential myocardial imaging radiopharmaceutical applicable in cardiology

Labeling of epirubicin with technetium-99m: Optimization, biodistribution and scintigraphic imaging in tumor bearing mice

Epirubicin is an antineoplastic agent of anthracycline antibiotic, used for treating a variety of tumor types such as lymphoma, cancer of the breast, lung, ovary and stomach. The objective of this work was to demonstrate direct radiolabeling of epirubicin with 99mTc, quality control, biological characterization and scientigraphic evaluation in tumor bearing mice. The 99mTc-epirubicin labeling was optimized by varying the amounts of ligand 100-350microg, stannous chloride dihydride 20-50microg and pH range 2-10 by using NaOH or HCl. The radiochemical purity of 99mTc-epirubicin was evaluated by chromatographic techniques [Whatman No. 3 paper and ITLC-SG]. HPLC analyses were performed to check purity of epirubicin and radiochemical purity of labeled 99mTc- epirubicin. Biodistribution and scintigraphic imaging of 99mTc-epirubicin was performed in normal and tumor bearing mice at various time intervals. The optimum conditions ensuring 99mTc-epirubicin labeling yield as high as 99% by adding 35microg SnCl2.2H2O, 200microg of ligand at pH 6 for 30 min at room temperature [25 degree C +/- 2 degree C]. HPLC of 99mTc-epirubicin shows about 99% binding of the compound with technetium-99m. Electrophoresis study indicated the neutral nature of 99mTc-epirubicin. Biodistribution data and scintigraphic results showed that 99mTc-epirubicin accumulated in the liver as well as in tumor with significant uptake and excellent retention. 99mTc-epirubicin shows good stability in human serum. In vitro and in vivo studies revealed the significantly uptake of 99mTc-epirubicin in the tumor, and also indicating the efficiency of 99mTc-epirubicin as a tumor diagnostic agent

Preparation, biodistribution and scintigraphic evaluation of [99m]Tc-lincomycin

A complex of lincomycin was synthesized with technetium-99m. The synthesis was carried out by using SnCl[2].2H[2]O as reducing agent and ascorbic acid as stabilizer. The effect of various parameters such as amount of ligand/reducing agent, pH value and reaction time on radio labeling process was studied. The characterization of the [99m]Tc-Lincomycin was performed by HPLC and electrophoresis Biodistribution studies were carried out by analyzing the model of bacterial infectious rats [Sprague-Dawley]. The uptake of infectious lesions at different time interval was also studied by using scintigraphic technique. The complex showed effective target to non-target ratio for various inflammatory or infectious lesions. The [99m]Tc-Lincomycin effective binding to living bacteria and could be used successfully as an infection imaging agent