title: Antimicrobial photodynamic efficiency of novel cationic porphyrins towards periodontal Gram-positive and Gram-negative pathogenic bacteria.
abstract: The Gram-negative Aggregatibacter actinomycetemcomitans and Fusobacterium nucleatum are major causative agents of aggressive periodontal disease. Due to increase in the number of antibiotic-resistant bacteria, antimicrobial Photodynamic therapy (aPDT) seems to be a plausible alternative. In this work, photosensitization was performed on Gram-positive and Gram-negative bacteria in pure culture using new-age cationic porphyrins, namely mesoimidazolium-substituted porphyrin derivative (ImP) and pyridinium-substituted porphyrin derivative (PyP). The photophysical properties of both the sensitizers including absorption, fluorescence emission, quantum yields of the triplet excited states and singlet oxygen generation efficiencies were evaluated in the context of aPDT application. The studied porphyrins exhibited high ability to accumulate into bacterial cells with complete penetration into early stage biofilms. As compared with ImP, PyP was found to be more effective for photoinactivation of bacterial strains associated with periodontitis, without any signs of dark toxicity, owing to its high photocytotoxicity.
authors.affiliation: Biophotonics Laboratory, Centre for Earth Science Studies, Trivandrum, India.
authors.forename: Chandra Sekhar
authors.initials: CS
authors.lastname: Prasanth
authors.forename: Suneesh C
authors.initials: SC
authors.lastname: Karunakaran
authors.forename: Albish K
authors.initials: AK
authors.lastname: Paul
authors.forename: Vesselin
authors.initials: V
authors.lastname: Kussovski
authors.forename: Vanya
authors.initials: V
authors.lastname: Mantareva
authors.forename: Danaboyina
authors.initials: D
authors.lastname: Ramaiah
authors.forename: Leslie
authors.initials: L
authors.lastname: Selvaraj
authors.forename: Ivan
authors.initials: I
authors.lastname: Angelov
authors.forename: Latchezar
authors.initials: L
authors.lastname: Avramov
authors.forename: Krishnankutty
authors.initials: K
authors.lastname: Nandakumar
authors.forename: Narayanan
authors.initials: N
authors.lastname: Subhash
mesh_terms: D002412:Cations; D006090:Gram-Negative Bacteria / Q000302:isolation & purification*; D006094:Gram-Positive Bacteria / Q000302:isolation & purification*; D009682:Magnetic Resonance Spectroscopy; D010519:Periodontium / Q000382:microbiology*; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000494:pharmacology*; D011166:Porphyrins / Q000494:pharmacology*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D002412:Cations; D017319:Photosensitizing Agents; D011166:Porphyrins