Development of water-soluble single-crystalline TiO₂ nanoparticles for photocatalytic cancer-cell treatment

The fabrication of water-soluble and biocompatible TiO₂ nanoparticles and their photocatalytic capabilities for applications to skin cancer cells, are discussed. TiO₂ nanoparticles, synthesized by a high-temperature nonhydrolytic method, are single-crystalline anatase, and are insoluble in water due to hydrophobic capping ligands. To make them water soluble, surface modification of these nanoparticles was performed, and these particles were coated with DMSA (2,3-dimercaptosuccinic acid). These nanoparticles represented superior photocatalytic capabilities to be applicable for the cancer cell treatment to that of the commercial Degussa P-25. These capabilities were attributed to the high surface-to-volume ratio and single crystallinity of these TiO₂ nanoparticles. These qualities increased the photocatalytic efficiency by increasing the number of catalytic sites and also enhancing the delocalization of carriers to reduce electron-hole pair recombination.