The PhD project deals with synthesis and characterization of organic photosensitizers in particular porphyrins and expanded porhyrins (pentaphyrins) for potential application in water disinfection. The growing population of harmful microbes and the development of resistance towards disinfectants/drugs calls for alternative and efficient methods of microbe destruction. Photodynamic therapy or photoinactivation is one such method that uses individually harmless components to destroy microorganisms. In view of this, we have carried out series of trial synthesis for new photsensitizers in particular expanded porphyrins. The aim is to obtain photosensitizers that can deliver broad spectrum of action against both Gram positive and Gram negative bacteria and also other pathogenic organisms. On the other hand, the immobilization of porphyrins onto solid supports like magnetic nanoparticles and polymers were also studied so that the recovery and reuse of photosensitizers is possible. The polymer supported photosensitizers have remarkable photodynamic activity against Gram positive bacteria in presence of visible light and looks promising for further study as well as application in treating water bodies to make them microbe free.
