title: Synthesis and properties of 5,10,15,20-tetrakis[4-(3-N,N-dimethylaminopropoxy)phenyl] chlorin as potential broad-spectrum antimicrobial photosensitizers.
abstract: A novel 5,10,15,20-tetrakis[4-(3-N,N-dimethylaminopropoxy)phenyl]chlorin (TAPC) was synthesized by reduction of the corresponding porphyrin TAPP with p-toluenesulfonhydrazide, followed by selective oxidation with o-chloranil. Spectroscopic properties and the photodynamic activity of these photosensitizers were compared in N,N-dimethylformamide. An increase in the absorption band at 650nm was found for the chlorin derivative with respect to TAPP. These photosensitizers emit red fluorescence with quantum yields of 0.15. Both compounds were able to photosensitize singlet molecular oxygen with quantum yields of about 0.5. Also, the formation of superoxide anion radical was detected in the presence of TAPC or TAPP and NADH. Photodynamic inactivation was investigated on a Gram-positive bacterium Staphylococcus aureus, a Gram-negative bacterium Escherichia coli and a fungal yeast Candida albicans cells. In vitro experiments showed that TAPC or TAPP were rapidly bound to microbial cells at short incubation periods. These photosensitizers, without intrinsic positive charges, contain four basic amino groups. These substituents can be protonated at physiological pH, increasing the interaction with the cell envelopment. Photosensitized inactivation improved with an increase of both photosensitizer concentrations and irradiation times. After 15min irradiation, a 7 log reduction of S. aureus was found for treated with 1μM photosensitizer. Similar result was obtained with E. coli after using 5μM photosensitizer and 30min irradiation. Also, the last conditions produced a decrease of 5 log in C. albicans cells. Therefore, TAPC was highly effective as a broad-spectrum antimicrobial photosensitizer.
authors.affiliation: Departamento de Química, Facultad de Ciencias Exactas Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Agencia Postal Nro. 3, X5804BYA, Río Cuarto, Córdoba, Argentina.
authors.forename: Darío D
authors.initials: DD
authors.lastname: Ferreyra
authors.affiliation: Departamento de Química, Facultad de Ciencias Exactas Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Agencia Postal Nro. 3, X5804BYA, Río Cuarto, Córdoba, Argentina.
authors.forename: Eugenia
authors.initials: E
authors.lastname: Reynoso
authors.affiliation: Departamento de Química, Facultad de Ciencias Exactas Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Agencia Postal Nro. 3, X5804BYA, Río Cuarto, Córdoba, Argentina.
authors.forename: Paula
authors.initials: P
authors.lastname: Cordero
authors.affiliation: Departamento de Química, Facultad de Ciencias Exactas Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Agencia Postal Nro. 3, X5804BYA, Río Cuarto, Córdoba, Argentina.
authors.forename: Mariana B
authors.initials: MB
authors.lastname: Spesia
authors.affiliation: Departamento de Química, Facultad de Ciencias Exactas Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Agencia Postal Nro. 3, X5804BYA, Río Cuarto, Córdoba, Argentina.
authors.forename: M Gabriela
authors.initials: MG
authors.lastname: Alvarez
authors.affiliation: Departamento de Química, Facultad de Ciencias Exactas Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Agencia Postal Nro. 3, X5804BYA, Río Cuarto, Córdoba, Argentina.
authors.forename: M Elisa
authors.initials: ME
authors.lastname: Milanesio
authors.affiliation: Departamento de Química, Facultad de Ciencias Exactas Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Agencia Postal Nro. 3, X5804BYA, Río Cuarto, Córdoba, Argentina. Electronic address: edurantini@exa.unrc.edu.ar.
authors.forename: Edgardo N
authors.initials: EN
authors.lastname: Durantini
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D017319:Photosensitizing Agents / Q000494:pharmacology*; D011166:Porphyrins / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D013050:Spectrometry, Fluorescence / Q000379:methods; D013056:Spectrophotometry, Ultraviolet / Q000379:methods
chemical_list: D000890:Anti-Infective Agents; D017319:Photosensitizing Agents; D011166:Porphyrins; C006969:chlorin
keywords: Chlorin; Microorganisms; Photodynamic activity; Photoinactivation; Porphyrin