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Title: Rose bengal-integrated electrospun polyacrylonitrile nanofibers for photodynamic inactivation of bacteria
Electrospun polyacrylonitrile (PAN) nanofibers integrated with different loadings of the photosensitizer rose bengal (RB) were synthesized for photodynamic inactivation of bacteria. Our results suggest that the ionic strength in the medium does not significantly affect the RB release from the RB-integrated electrospun PAN nanofibers (RBiEPNs), which could release RB effectively in phosphate-buffered saline (PBS), physiological saline (0.85% NaCl), and deionized H 2 O. However, the pH of the medium significantly influenced the release of RB. A larger amount of RB was released in PBS at a higher pH (RB release: pH 9.0 > pH 7.4 > pH 5.0). The RBiEPNs depicted high antimicrobial efficacy against both Gram-negative Escherichia coli ( E. coli ) and Gram-positive Bacillus subtilis ( B. subtilis ) bacteria under white light irradiation. The antimicrobial efficacy was potent and immediate against the bacterial cells, especially B. subtilis . The RBiEPNs containing 0.33 wt% RB demonstrated complete bacterial kills for B. subtilis and E. coli cells with log reductions of 5.76 and 5.94 in 30 s and 40 min, respectively. The generation of intracellular reactive oxygen species (iROS) was examined after white light treatment of the bacterial cells in the presence of the RBiEPNs. A significant correlation was found between the amount of iROS and the antimicrobial efficacy of the RBiEPNs. The high antimicrobial efficacy could be attributed to several factors, such as the encapsulation efficiency, loading capacity, and RB release behavior of the RBiEPNs, the presence of white light, and the generation of iROS. Taken together, the facile incorporation of a photosensitizer into polymeric nanofibers via blend electrospinning offers a feasible strategy for water disinfection.  more » « less
Award ID(s):
1831133 2122044
NSF-PAR ID:
10374111
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Environmental Science: Advances
ISSN:
2754-7000
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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