Nanosilver Could Usher in Next‐Generation Photoprotective Agents for Magnesium Porphyrins

Abstract

A novel strategy, based on silver nanoparticles (AgNPs), has been developed for simultaneously improving: 1) photostability, 2) fluorescence emission, and 3) singlet oxygen generation ability of natural porphyrin (i.e., chlorophyll (Chl) molecules). The benefit of AgNPs as photoprotector of Chl is that they spontaneously bind with the nitrogen atoms of Chl as soon as they are mixed together, even in the dark prior to the illumination, inhibiting thus the binding of reactive oxygen species (ROS) at nitrogen sites, known to cause the photodegradation of porphyrins.

In Situ Reduction of Silver by Polydopamine: A Novel Antimicrobial Modification of a Thin-Film Composite Polyamide Membrane

“…According to Yang et al, electrons released by the oxidation of catechol to quinone can reduce silver ions in the solution phase. At the same time, the O- and N-based ligand sites in PDA could serve as anchors for the resulting AgNPs. , …”

“…At the same time, the O-and N-based ligand sites in PDA could serve as anchors for the resulting AgNPs. 40,41 Figure 3a-d presents the TEM micrographs (plan view) of the control membrane XLE and the silver incorporated membranes. Consistent with the SEM micrographs (Figure 2), the TEM micrographs also show the "ridge and valley" structure of the polyamide rejection layer.…”

Metal-enhancement study of dual functional photosensitizers with aggregation-induced emission and singlet oxygen generation

“…More recently, these localised SPR effects have been exploited to enhance the optoelectronic properties of functional materials, such as uorophores and photosensitizers, leading to a new eld of studying metal-enhanced uorescence (MEF) [30][31][32][33][34][35][36][37][38][39][40][41] and singlet oxygen generation (ME-SOG). [42][43][44][45][46][47][48] To date, several works have been reported to tune the distance between the uorophore and the metallic surface in controlling the plasmonic-enhancement effects. [49][50][51] For example, Liang et al 49 employed the layer-by-layer (LBL) technique to control the distance between the conjugated polymeric uorophore (PFVBT) and silver nanocubes (for up to three bilayers) by using oppositely charged polyelectrolytes for the assembly.…”

“…Due to the interactions of the excited uorophore and plasmonic NPs, 42,48,[52][53][54] photostability and SOG rate of the photosensitizers could be enhanced. 43 For instance, Ke and coworkers 55 have reported the simultaneous enhancement of uorescence and SOG of the aluminium phthalocyanine on the surface of Au@silica nanorods. However, no correlation was found between the optimum distance for MEF and ME-SOG.…”

A novel PVDF hybrid membrane with excellent active–passive integrated antifouling and antibacterial properties based on a PDA guiding effect

“…Furthermore, the O sites and N sites of PDA can serve as anchors to guide the immobilization of AgNPs on PDA microspheres through metal coordination. 45,46 Therefore, we propose that it is the guiding reduction effect of PDA microspheres on Ag + that greatly enhances the quantity and efficiency of the generation of AgNPs on the substrate interior. The existence of numerous AgNPs on the cross-section specifically imparted the membranes with excellent hydrophilicity, permeability, and antifouling performance during the filtration process.…”