Development of a pyrogallol-formaldehyde resin column for one-step pre-purification of 68Ge/68Ga generator eluates: Enhanced [68Ga]Ga-DOTA-TATE radiolabeling yield by selective removal of tetravalent cationic impurities.

A pyrogallol-formaldehyde resin (PGR) column was developed for one-step pre-purification of 68Ge/68Ga generator eluates. The resin selectively adsorbs tetravalent cations (Ge4+, Sn4+, Ti4+) with efficiencies of 81.8%, 42.4%, and 29.8% in standards, reducing Sn4+ and Ti4+ to undetectable levels in generator eluates. Formaldehyde leaching was negligible, and cell viability remained 98% ± 1.7%, confirming biocompatibility. 68Ge breakthrough decreased >20-fold (0.0008 ± 0.0001% to 0.00003 ± 0.00002%). Manual [68Ga]Ga-DOTA-TATE labeling yield increased from 58.9 ± 6% to 75.9 ± 1.8% (n = 10). The column is reusable for ≥10 runs. PGR enables high-purity, high-yield 68Ga radiopharmaceutical synthesis without additional processing time, resolving pH-dependent tetravalent cation interference via colloid mitigation.