The convenient screening method using albumin for the tumor localizing property of Ga-porphyrin complexes

Eleven Ga-phorphyrin complexes bearing various lengths of carbon-chain were synthesized and the UV–vis spectra shift patterns in various concentrations of albumin solutions were evaluated. The distributions of these derivatives into the organs were also determined by surface fluorescence using nitrogen-pulsed laser spectrophotometry. The shift patterns between 0 and 0.9% albumin concentrations (albumin test) were correlated to their tumor localizing property. The albumin test was proved to be useful for evaluation of tumor localizing properties of porphyrin derivatives. The tumor localizing ability was increased along with increasing their lipophilicity and the derivative bearing decyl groups as side chains was a maximum. The porphyrin–albumin complex might have key mission for the passive accumulation focusing on the tumor.