3.3.5 Paladium-109
Beta-emitting
109 Pd labeled porphyrins have been used for various radiopharmaceutical applications [61].
109
Pd-hematoporphyrin or
100 Pd-protoporphyrin were
explored in homograft rejection studies [62]. Water soluble
109 Pd porphyrins were
also employed for biodistribution studies in mice bearing various types of tumors
[27]. Banerji’s group prepared a water soluble 5,10,15,20-tetrakis(3,4-bis(carboxymethyleneoxy)phenyl)porphyrin radiolabeled 18 labeled with
109 Pd [63].
Biodistribution revealed high tumor-to-blood and tumor-to-muscle ratios (4.4 and
38 at 24 h post-injection). Moreover, the complex showed predominant renal
clearance (89%, 24 h post-injection). The same group developed
109 Pd labeled
5,10,15,20-tetrakis(3,4-bis(carboethoxymethyleneoxy)phenyl)-porphyrin 19 [64]
and biodistribution data revealed efficient tumor uptake in Swiss mice bearing
fibrosarcomas.
N
HN
N
NH
OCH 2 COOH
HOOCH 2 CO
HOOCH 2 CO
OCH 2 COOH
HOOCH 2 CO
OCH 2 COOH
OCH 2 COOH
HOOCH 2 CO
18
N
HN
N
NH
OCH 2 COOC 2 H 5
C 2 H 5 OOCH 2 CO
C 2 H 5 OOCH 2 CO
OCH 2 COOC 2 H 5
C 2 H 5 OOCH 2 CO
OCH 2 COOC 2 H 5
OCH 2 COOC 2 H 5
C 2 H 5 OOCH 2 CO
19
3 Porphyrin and Phthalocyanine Radiolabeling
65