| Publication Type |
Journal Article |
| Title |
Photoinactivation of Planktonic and Biofilm Forms of Escherichia coli through the Action of Cationic Zinc(II) Phthalocyanines |
| Authors |
Leandro M. O. Lourenco Deisy M. G. C. Rocha V Ramos Maria C. Gomes Adelaide Almeida Maria A. F. Faustino Filipe A. Almeida Paz Maria G. P. M. S. Neves Angela Cunha João P. C. Tomé |
| Groups |
CCC |
| Journal |
CHEMPHOTOCHEM |
| Year |
2019 |
| Month |
May |
| Volume |
3 |
| Number |
5 |
| Pages |
251-260 |
| Abstract |
Novel water-soluble zinc(II) phthalocyanines (ZnPc) peripherally substituted with 4-dimethylaminopyridine (DMAP) units (ZnPc 1-2) and the corresponding quaternized derivatives (ZnPc 1a-2a) were synthesized and their photodynamic inactivation (PDI) efficiency against a Gram-negative bacterium, a recombinant bioluminescent Escherichia coli strain either in planktonic or biofilm form, was investigated. The analysis of the photophysical properties revealed that the increase in the number of DMAP units on ZnPc shifted the absorption and emission band in aqueous media to the red region. The presence of multi-positive charges on ZnPc derivatives prevented aggregation and enhances the solubility in aqueous media. The quaternized derivatives ZnPc 1a and 2a displayed good stability and promising efficacy to generate singlet oxygen (O-1(2)). The affinity of the amphiphilic ZnPc 1-2 and quaternized ZnPc 1a-2a to planktonic bacterial cells corresponded to an average uptake of approximate to 10(6)PS molecules.CFU-1. The PDI assays conducted with planktonic cells and biofilms of E. coli show that irradiation with red or white light (150mW.cm(-2)) in the presence of 20M of ZnPc derivatives caused an effective inactivation. ZnPc 1a and ZnPc 2a exhibited the highest inactivation efficiency, particularly of the planktonic form, causing a 5log-scale (99.99\%) reduction in bioluminescence. The inactivation factor for biofilms was 99\% (2log). ZnPc 1a and ZnPc 2a can be regarded as promising photosensitizers for the photodynamic inactivation of Gram-negative bacteria. |
| DOI |
http://dx.doi.org/10.1002/cptc.201900020 |
| ISBN |
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| Publisher |
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| Book Title |
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| ISSN |
2367-0932 |
| EISSN |
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| Conference Name |
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| Bibtex ID |
ISI:000471813800007 |
| Observations |
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