Porphyrin Polymers Bearing N,N0-Ethylene Crosslinkers as Photosensitizers against Bacteria

SANTAMARINA, SOFÍA C.; HEREDIA, DANIEL A.; DURANTINI, ANDRÉS M.; DURANTINI, EDGARDO N.

Polymers

MDPI - Publisher of Open Access Journals

Año: 2022

2073-4360

The appearance of microbes resistant to antibiotics requires the development of alternativetherapies for the treatment of infectious diseases. In this work two polymers, PTPPF16-EDAand PZnTPPF16-EDA, were synthesized by the nucleophilic aromatic substitution of 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin and its Zn(II) complex with ethylenediamine, respectively. Inthese structures, the tetrapyrrolic macrocycles were N,N0-ethylene crosslinked, which gives themgreater mobility. The absorption spectra of the polymers showed a bathochromic shift of the Soretband of ~10 nm with respect to the monomers. This effect was also found in the red fluorescenceemission peaks. Furthermore, both polymeric materials produced singlet molecular oxygen with highquantum yields. In addition, they were capable of generating superoxide anion radicals. Photodynamicinactivation sensitized by these polymers was tested in Staphylococcus aureus and Escherichia colibacteria. A decrease in cell viability greater than 7 log (99.9999%) was observed in S. aureus incubatedwith 0.5 M photosensitizer upon 30 min of irradiation. Under these conditions, a low inactivationof E. coli (0.5 log) was found. However, when the cells were treated with KI, the elimination ofthe Gram-negative bacteria was achieved. Therefore, these polymeric structures are interestingantimicrobial photosensitizing materials for the inactivation of pathogens.