Microorganisms Photocatalytic Inactivation on Ag3PO4 Sub-Microcrystals Under WLEDs Light Source

Abstract

In this article, we report the silver orthophosphate (Ag3PO4) photocatalytic inactivation properties on strains Gram-positive Saprophyte B. subtilis, a diploid fungus Candida albicans and Gram-negative Pseudomonas aeruginosa, using as irradiation source white-light-emitting diodes (WLEDs) with luminous flux ( v) of 1.3 x 10 3 Lumens and relative power density of 15 mW m -2 . Microorganisms death curves and the kinetic constants (Kd) indicated that the inhibitory effect of the Ag3PO4 under WLEDs irradiation is well pronounced to C. albicans (6.6 x 10 -2 min -1 ) in relation to P. augenosas (4.6 x 10 -2 min -1 ) and B. subitilis (2.5 x 10 -2 min -1 ). Decimal reduction time (Dt) were 34.4 min to C. albicans, 50.1 min P. augenosas and 92.1 min to B.subitilisThe micrographs obtained by scanning electron microscopy with field emission gun (SEM-FEG) demonstrated that there was cell wall permeability and consequently total rupture in the C. albicans, suggesting the lipid peroxidation phenomenon and protein oxidation promoted by the presence of reactive oxygen species (ROS). Furthermore, it was observed the Ag3PO4 when irradiated by WLEDs demonstrates important sporicidal activity in related to B. subtilis, promoting the endospore wall rupture.

Effect of the Cross-Section Morphology in the Antimicrobial Properties of α-Ag2WO4 Rods: An Experimental and Theoretical Study

“…Our research group and other authors have been involved in a research field in which complex silver-based oxides, such as Ag 2 CrO 4 [9,10], the three polymorphs of Ag 2 WO 4 [11][12][13][14], Ag 3 PO 4 [15,16], α-AgVO 3 [17], and β-Ag 2 MoO 4 [18][19][20][21], are investigated as biocide materials. α-Ag 2 WO 4 becomes even more interesting because it absorbs a large amount of radiation in the visible region and has optoelectronic properties closely related to particle size, allowing for better control [11,12,[22][23][24][25][26][27].…”

Inactivation of SARS-CoV-2 by a chitosan/α-Ag2WO4 composite generated by femtosecond laser irradiation

“…and devices for disinfection of surfaces/surroundings. In particular, different complex silver-based oxides with potent antibacterial and antifungal activities have been presented, such as Ag 2 CrO 4 6 , 7 , the three polymorphs of Ag 2 WO 4 8 , 9 , Ag 3 PO 4 10 , 11 , α-AgVO 3 12 and β-Ag 2 MoO 4 13 . To provide a deeper understanding and establish a correlation among morphology, surface energy and biocidal activity, first principles calculations were conducted at the density functional theory (DFT) level to complement and rationalize the experimental findings 14 .…”

Bioactive Ag3PO4/Polypropylene Composites for Inactivation of SARS-CoV-2 and Other Important Public Health Pathogens

“…However, their success and applicability largely depend on previous experience. Our research group has been developing potent biocide materials based on complex silver-based oxides, such as Ag 2 CrO 4 , , three polymorphs of Ag 2 WO 4 , , Ag 3 PO 4 , , α-AgVO 3 , and β-Ag 2 MoO 4 with enhanced antifungal activity. Additionally, to provide a deeper understanding of the atomic and electronic structure and to establish a correlation between the morphology and the biocide activity, we conducted first-principles calculations at the DFT level to complement and rationalize the experimental findings …”