Open AccessSynthesis, photophysical properties and photodynamic antimicrobial activity of meso 5,10,15,20-tetra(pyren-1-yl)porphyrin and its indium(III) complex
Author(s) -
Jackline N Khisa,
Solomon Derese,
John Mack,
Edith Amuhaya,
Tebello Nyokong
Publication year - 2021
Publication title -
journal of porphyrins and phthalocyanines
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.322
H-Index - 64
eISSN - 1099-1409
pISSN - 1088-4246
DOI - 10.1142/s1088424621500462
Subject(s) - porphyrin , chemistry , quantum yield , bathochromic shift , free base , photochemistry , indium , intersystem crossing , fluorescence , singlet state , organic chemistry , excited state , salt (chemistry) , quantum mechanics , nuclear physics , physics
In this study, free-base meso 5,10,15,20-tetra(pyren-1-yl)porphyrin (H 2 TPyP) and its corresponding indium(III) complex (InClTPyP) were synthesized and characterized on the basis of mass spectrometry, 1 H NMR spectroscopy and elemental analysis. InClTPyP was obtained in good yield by treating the free base H 2 TPyP with indium(III) chloride. Purification of these compounds was achieved through column chromatography using different solvent systems. Metallation of the free base to form a metallo-porphyrin afforded improved photophysical properties. There was a bathochromic shift in wavelength of absorption from the parent free base H 2 TPyP ([Formula: see text] = 431 nm) to metallated indium(III) complex ([Formula: see text] = 443 nm). The fluorescence quantum yield in H 2 TPyP was higher ([Formula: see text] = 0.131) than in InClTPyP ([Formula: see text] = 0.017) due to efficient intersystem crossing to the triplet manifold in the metallated porphyrin. Upon illumination, both H 2 TPyP and InClTPyP show effective dose dependent antimicrobial activity against Staphylococcus aureus with photoinactivation IC[Formula: see text] values of 27.89 and 16.67 [Formula: see text]M, respectively.