Porphyrins and porphyrin-derivatives have been described as successful PSs for PDT, some of them being approved for clinical use. Trying to advance in the development of PDT PSs, other chromophoric scaffolds (phtalocyanine, fullerene, BODIPY, etc.) have been reported as potentially interesting to develop advanced systems able to overcome some of the drawbacks. In this context, BODIPY have revealed as valuable dyes for the development of new PSs due to their outstanding chemical and physical features such as high absorption coefficients in the Vis region, high resistance to photobleaching low dependence of the photophysical signatures with the environmental conditions (e.g., solvent polarity), as well as small size and high lipophilicity, facilitating biological-membrane penetration. On the other hand, the high chemical versatility of the BODIPY core, amenable by the rich well-known BODIPY chemistry, allows exhaustive and selective modification of the chromophoric BODIPY core (BODIPY functionalization), making possible the fine modulation of photophysical properties. This work focuses on the contributions of our research group on the application of novel BODIPYs as singlet oxygen photosensitizers from the two perspectives that are commonly considered as effective (1) Attaching heavy atoms (mainly iodine and bromine, but also transition metals) to the BODIPY and (2) orthogonal BODIPY dimers. Moreover, the accessible fine chemical modulation of BODIPY properties makes possible to balance 1O2 photogeneration and fluorescence, which is interesting to develop PDT + bioimaging theranostic agentsas well as to modulate other physical and chemical properties interesting for the searched photo-biological activity (e.g., water solubility and membrane permeability Finally, BODIPYs with functional groups of interest to be anchored to different nanocarriers are also described.
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