Photosensitization of phthalocyanine for singlet oxygen generation in photodynamic therapy applications

In this work, phthalocyanine and its OCH3 derivatives were investigated to see their photosensitization characteristics for producing singlet molecular oxygen, which is important in photodynamic therapy type-II. All structures were first optimized to achieve the minimized energy 3D models Subsequently, they were prepared for the photosensitization investigations. All the experiments were conducted based on the density functional theory calculations. The energy absorption and emission observed between the occupied and unoccupied molecular orbitals based on the required energy for excitation and the corresponding energy of emission. The results indicated that the OCH3 models could be expected to be safer than the original phthalocyanin by their required energy at longer wavelengths. The ratio of singlet molecular oxygen generation was found to be 1:1 for each of the OCH3 derivatives.