Recent Strategies to Develop Innovative Photosensitizers for Enhanced Photodynamic Therapy

Abstract

This review presents a robust strategy to design photosensitizers (PSs) for various species. Photodynamic therapy (PDT) is a photochemical-based treatment approach that involves the use of light combined with a light-activated chemical, referred to as a PS. Attractively, PDT is one of the alternatives to conventional cancer treatment due to its noninvasive nature, high cure rates, and low side effects. PSs play an important factor in photoinduced reactive oxygen species (ROS) generation. Although the concept of photosensitizer-based photodynamic therapy has been widely adopted for clinical trials and bioimaging, until now, to our surprise, there has been no relevant review article on rational designs of organic PSs for PDT. Furthermore, most of published review articles in PDT focused on nanomaterials and nanotechnology based on traditional PSs. Therefore, this review aimed at reporting recent strategies to develop innovative organic photosensitizers for enhanced photodynamic therapy, with each example described in detail instead of providing only a general overview, as is typically done in previous reviews of PDT, to provide intuitive, vivid, and specific insights to the readers.

A Review on Cellulose-based Materials for Biomedicine

“…Photo-based treatments using light radiation are promising for antibiotic resistance bacteria (Table 1) [81][82][83][84]. They required the presence of photosensitizer molecules that absorb the light radiation and convert it to thermal energy (photothermal therapy) or generation reactive species (i.e., photodynamic treatment) such as reactive oxygen species (ROS).…”

“…hypocrellin [91], xanthene [68], BODIPY (Dipyrrometheneboron difluoride) [81,92], chlorin-e6 [93], phthalocyanines [94,95], protoporphyrin-IX [96][97][98], and porphyrin [86,87,[99][100][101][102][103][104].…”

“…Por(+)-the paper was illuminated using visible light of wavelength and power of 400-700 nm and 65 ±5 mW/cm2, respectively, for 30 min. Cationic porphyrin (Por(+)) conjugated cellulose was performed as paper for scalable antimicrobial treatment using PDI [81]. The antibacterial and antiviral efficacies were investigated against bacteria (S. aureus, vancomycinresistant Enterococcus faecium (VER), Acinetobacter baumannii, P.aeruginosa, and Klebsiella pneumoniae) and viruses (dengue-1 virus, influenza A, and human adenovirus-5).…”

Fluorescence Microscopy—An Outline of Hardware, Biological Handling, and Fluorophore Considerations

“…This conjugate was found to localise within the mitochondria of cells, which is the major cite of ROS production. The use of organic fluorophores in theranostics and photo-dynamic therapies has been well covered in the literature and the reader is directed to some excellent reviews on these topics [ 287 , 288 ].…”

Feature-Based Molecular Networking—An Exciting Tool to Spot Species of the Genus Cortinarius with Hidden Photosensitizers

“…After irradiation with a suitable light source, the PS reaches an excited state, transfers its excess energy to environmental triplet oxygen, and generates singlet oxygen ( 1 O 2 /Type II reaction), inducing cell death [10,11]. PDT in its current state heavily depends on porphyrin-like structures and transition metal complexes [12,13], whereas the search for new photoactive scaffolds from nature is neglected [14].…”