The emergence of microbial resistance to antimicrobial drugs and the environmental impacts of disinfectants and antifouling agents are becoming increasing problems in the clinic and environmental areas. Antimicrobial photodynamic therapy (aPDT) has been receiving considerable attention as a new antimicrobial approach. that circumvents some of the major drawbacks of classic antimicrobial chemotherapy. Recent studies have shown that aPDT is efficient, affordable, ready availability, safe, causes low environmental impacts and does not induce the development of resistance. Antimicrobial photodynamic therapy combines a nontoxic photosensitizer (PS), with visible light to generate singlet oxygen and free radicals that kill microbial cells (Merchat et al 1996; Minnock et al 1996). The main advantages of aPDT are the non-target specificity and the potential lack of development of resistance mechanisms due to the mode of action and type of biochemical targets (multi-target process) (Jori et al. 2004, Winckler 2007). In recent years, a great effort has been put in the search for more effective photosensitizers but the lack of standardized methodologies to conduct photoinactivation experiments and photophysical studies often complicates the comparison of results retards the targeted-design of photosensitizers.

This proposal aims the development of standardized protocol of screening of the photoinctivation efficiency of porphyrinic and corrole derivatives that can establish the methodological basis for a collaborative research project involving the two institutions.