Modified porphyrin-brucine conjugated to gold nanoparticles and their application in photodynamic therapy.

Two porphyrin-brucine quaternary ammonium salts were immobilized on gold nanoparticles and their suitability for both in vitro and in vivo photodynamic therapy (PDT) was assayed using the basaloid squamous cell carcinoma PE/CA-PJ34 cell line. In vitro PDT experiments revealed that the gold nanoparticle-bound conjugates were less effective than unbound conjugates in killing cells. However, the same conjugates were more effective in reducing tumor size in vivo, with complete tumor regression observed.