Study of Photodegradation in Response to Photodynamic Therapy Using Raman Spectroscopy

• Grant number: 10/06114-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2010
• End date: February 28, 2011
• Field of knowledge: Biological Sciences - Biophysics - Radiology and Photobiology
• Principal Investigator: Juliana Ferreira Strixino
• Grantee: Joyce Ramos
• Host Institution: Instituto de Pesquisa e Desenvolvimento (IP&D). Universidade do Vale do Paraíba (UNIVAP). São José dos Campos , SP, Brazil

Abstract

The widely-used therapies for the treatment of cancer (such as surgery, chemotherapy, etc.) have side effects. Thus, there has been considerable effects develop of new techniques for fighting cancer. Recently, after extensive studies, photodynamic therapy (PDT) has emerged as a promising method for cancer treatment, and the only known side effect is skin and eye photosensitivity. However, PDT is still being studied because, there are some limitations and problems that need to be better understood in order to optimize treatment. Among these are the properties of photosensitizers and the interaction of light with sensitized biological tissues. The objective of this research is to investigate, using Raman spectroscopy, the correlation between the photodegradation of the photosensitizer Photogem® molecules with normal liver tissue necrosis in rats subjected to photodynamic therapy. Based on information obtained a mathematical model will be establish that allows correlation with data obtained by fluorescence spectroscopy, which was developed by the optical group at the Physics Institute of São Carlos (IFSC-USP). The photosensitizer what to be used is derivatives of hematoporphyrin and the sample prepared s will be analyzed by a Raman equipment in order to verify the correlation between the pharmacokinetics of photosensitizers with resulting tissue necrosis after PDT.