3.5. Radiolabeling of PSMA-HYNIC Derivatives

[^99mTc]Tc-PSMA-T1, [^99mTc]Tc-PSMA-T2, [^99mTc]Tc-PSMA-T3, [^99mTc]Tc-PSMA-T4 and [^99mTc]Tc-iPSMA (reference substance for in vivo study) were labeled in the presence of 5 mg of EDDA, 50 mg of tricine dissolved in 0.5 mL of 0.1 M phosphate buffer pH 7.4. After dissolution of reagents, 20 µg of PSMA, 20 µL of 1 mg/mL SnCl₂, 2H₂O solution in 0.1 M HCl, and 0.6–1 GBq of sodium pertechnetate (^99mTc) solution were added. The labeling mixture was incubated for 15 min at 95 °C.