Evaluation of formulations as a vehicle for delivering photosensitizers to the respiratory tract

• Grant number: 22/03965-6
• Support Opportunities: Scholarships in Brazil - Master
• Start date: November 01, 2022
• End date: February 29, 2024
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Vanderlei Salvador Bagnato
• Grantee: Isabelle Almeida de Lima
• Host Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated research grant: 13/07276-1 - CEPOF - Optics and Photonic Research Center, AP.CEPID

Abstract

Pneumonia is an infection characterized by inflammation of the alveoli that fill with fluid or pus, making it difficult to breathe and pass oxygen to the bloodstream. This infection is among the main causes of morbidity and mortality, mainly due to the difficulty of finding effective treatments against the increase in the rate of antibiotic-resistant microorganisms. Antimicrobial Photodynamic Therapy (aPDT) presents itself as a potential alternative, due to its high antimicrobial efficiency and non-specific action with a focus on multiple molecular targets, selectivity to the treatment site and non-invasive character. Studies carried out by our research group reported the efficiency and safety of a protocol for photoinactivation of Streptococcus pneumoniae in vitro, as well as the delivery of light and photosensitizer in an animal model. However, the reduction of microorganisms in vivo still presents challenges to be overcome, due to the presence of pulmonary surfactant. A promising strategy is the use of carriers/vehicles, where in high concentrations, the pulmonary surfactant (PS) itself can be used, as already reported by numerous studies that combined SP to several drugs. Another possibility is perfluorocarbon compounds (PFCs), which have high dissemination power, promoting a more uniform distribution of administered materials, increasing local effectiveness. Although formulations with several drugs have already been reported in the literature, as far as we know, there are no studies that report the use of SP and PFCs associated with photosensitizers. Thus, the present work aims to evaluate the efficiency of formulations using different photosensitizers and PS/PFCs as vehicles for photoinactivation of the microorganism Streptococcus pneumoniae.

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

LIMA, Isabelle Almeida de. Strategies for overcoming pulmonary surfactant barrier for successful antimicrobial photodynamic therapy. 2024. Master's Dissertation - Universidade de São Paulo (USP). Instituto de Física de São Carlos (IFSC/BT) São Carlos.