TAPY scaffolds have been identified as versatile mitochondrial-targeting agents in studies with cancer cells (A549, HT-29 and MCF-7). This finding paves the way for future developments utilizing this moiety to enhance bioimaging tools and mitochondrial-targeted anticancer drugs.

Quaternary ammonium compounds (QACs), particularly dicationic architectures, are well-known for their antimicrobial activity. This study explores the antimicrobial potential of several TAPY derivatives, demonstrating their broad-spectrum antifungal and antibacterial properties. 

Silica-encapsulated photosensitizers exhibit greater stability than their non-encapsulated counterparts. This enhanced stability has been leveraged to improve phototherapeutic efficiency against HeLa cancer cells, paving the way for advancements in photodynamic therapy (PDT).

Biofilms of Staphylococcus aureus are complex structures that are difficult to eradicate. A polymeric hydrogel system based on PHEMA, encapsulating a molybdenum-based photosensitizer, has demonstrated high efficacy in eliminating these recalcitrant bacterial reservoirs. 

Styrylpyrilium derivatives have been synthesized and characterized. A series of bioimaging studies in hepatoma (Hep3B) cells demonstrated mitochondrial localization, which could provide the basis for developing sensors or drugs targeted to this important cellular organelle. 

Nitric oxide (NO) plays numerous roles at the cellular level. The fluorescent sensor mtNOpy has been developed to image NO within the mitochondria of various cell types (e.g., HT-29 and RAW264.7) and can also differentiate phagocytes (neutrophils and monocytes) from other leukocytes (NK, B, and T cells) in peripheral blood.

Synthetic dyads comprising a BODIPY fluorophore and a pseudopeptidic targeting moiety have been designed to selectively target lysosomes in HT-29 cancer cells, enabling confocal microscopy imaging of this process. In addition, lysosomal imaging was also performed in a cellular model of lysosomal storage disease (Niemann–Pick type C). 

Two BODIPY(Br)-based photosensitizers with self-assembly capabilities have been studied against S. aureus and E. coli. Despite their ability to form particles extracellularly, the compounds are effective agents for bacterial photoinactivation, likely due to disassembly within the cellular interior. 

Identifying the products formed upon reaction of 1,2-diaminoanthraquinone (DAQ or DAA) enables mapping of nitric oxide (NO) production sites in stimulated RAW264.7 macrophages, thereby contributing to a better understanding of the biochemical roles of this reactive nitrogen species (RNS).

Selecting the appropriate excitation wavelength for confocal microscopy–based bioimaging is crucial to maximize the detectable signal. This study optimizes the excitation settings for nitric oxide (NO) detection in RAW264.7 macrophages using 1,2-diaminoanthraquinone (DAQ or DAA) as a fluorescent probe. 

The preparation of styrene-based materials loaded with Rose Bengal (as photosensitizer) is described, together with the photoantimicrobial properties of these polymers against Gram-positive and Gram-negative bacteria, as well as fungi (S. aureus, E. faecalis, E. coli, P. aeruginosa, and C. albicans).

PHEMA-based hydrogels encapsulating Rose Bengal form a flexible, transparent material that eradicates planktonic E. coli and P. aeruginosa upon white-light irradiation. This effect is accomplished after addition or iodide, which generates additional bactericidal species (triiodide and hydrogen peroxide). 

This work demonstrates the photobactericidal activity of macroporous styrene-based materials containing a molybdenum-based photosensitizer against Gram-negative P. aeruginosa. Notably, the material exhibits superior resistance to photobleaching compared with other well-known antimicrobial photosensitizing systems. 

Nitric oxide (NO) is detected in RAW264.7 cells via a fluorescence “off–on” response using one of the smallest NO sensors reported. This minimalistic design reduces perturbations and potential interferences from the probe in the cellular milieu. In addition, the underlying deamination mechanism is demonstrated.