Studies of the chemical and biological properties of the liver-imaging agent 99mTc-phytate.
The correlation between chemical formulation and biodistribution of 99mTc-phytate solutions was examined. On the basis of radiochemical analyses and biological experiments, the following optimum parameters were found: weight ratio of the anhydrous sodium phytate to SnCl2 18:1; concentration of phytate 5-6 g/l, pH of the injection solution 6-7. Maximum uptakes in rat organs were in the liver 95.8 +/- 3.26 at 15-20 min p.i., and in the spleen 3.98 +/- 0.79% 3 hours p.i. Two new methods for radiochemical analysis enabling the separation of three peaks were used: ITLC-SG Gelman chromatography and molecular sieving through Sephadex G-25. The bench-life of the injection solution was also checked during a 5-h period, as well as its shelf-life which was at least 6 months. Clinical examinations showed excellent visualization of the normal liver with discrete radiocolloid uptake in the spleen and no uptake in other tissues. With SPECT a more precise and clear localization of liver lesions was achieved especially due to the low uptake of 99mTc-phytate in the spleen.
D000818:Animals; D002855:Chromatography, Thin Layer; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008099:Liver / Q000000981:diagnostic imaging*; D008107:Liver Diseases / Q000000981:diagnostic imaging; D015609:Organotechnetium Compounds; D010833:Phytic Acid / Q000032:analysis / Q000378:metabolism*; D011854:Radiochemistry; D051381:Rats; D011919:Rats, Inbred Strains; D013667:Technetium / Q000032:analysis / Q000378:metabolism*; D013997:Time Factors; D014018:Tissue Distribution; D014055:Tomography, Emission-Computed
D015609:Organotechnetium Compounds; C026177:technetium phytate; D013667:Technetium; D010833:Phytic Acid