Aza-BODIPY-Based Nanomedicines in Cancer Phototheranostics

Abstract

Cancer phototheranostics, composed of optical diagnosis and phototherapy (including photodynamic therapy and photothermal therapy), is a promising strategy for precise tumor treatment. Due to the unique properties of near-infrared absorption/emission, high reactive oxygen species generation, and photothermal conversion efficiency, aza-borondipyrromethene (aza-BODIPY), as an emerging organic photosensitizer, has shown great potential for tumor phototheranostics. By encapsulating aza-BODIPY photosensitizers within functional amphiphilic polymers, we can afford hydrophilic nanomedicines that selectively target tumor sites via an enhanced permeability and retention effect, thereby efficiently improving diagnosis and therapeutic efficacy. Herein, in this spotlight article, we attempt to highlight our recent contributions in the development of aza-BODIPY-based nanomedicines, which comprises three main sections: (1) to elucidate the design strategy of aza-BODIPY photosensitizers and corresponding nanomedicines; (2) to overview their photophysical properties and biomedical applications in phototheranostics, including fluorescence imaging, photoacoustic imaging, photodynamic therapy, photothermal therapy, and synergistic therapy; and (3) to depict the challenges and future perspectives of aza-BODIPY nanomedicines. It is believed that this Spotlight on Applications article would illuminate the way of developing new aza-BODIPY nanomedicines as well as other organic photosensitizer-based nanomedicines for future clinical translation.

The TDDFT Excitation Energies of the BODIPYs; The DFT and TDDFT Challenge Continues

“…The BODIPY pigment and its derivatives are key entities for phototheranostics [1], including photodynamic therapy [2], functional optoelectronic materials [3], such as solar cells [4][5][6] and light emitting diodes [7], and stimuli-responsive materials [8][9][10][11]. In order to understand or predict the optical properties [12,13] of such important chromophore, and notably the lowest energy electronic transition, a very large number of investigations involving computational argumentations were reported but most of the time the correspondence between the calculated position and experimentally observed one turned out to be chronically poor, where differences ranging from 60 to 100 nm were commonly depicted [14][15][16][17][18][19][20][21][22][23][24][25][26][27].…”

Photodynamic therapy: photosensitizers and nanostructures

“…8,40 Aza-BODIPY have been suggested to be closer to clinical development than any subcategory in their category, and although they are less synthetically accessible, 16 they currently attract wide research attention. 41 In general terms, BODIPY-based PSs are hydrophobic, but as in the previously commented species, hydrophilic derivatives can be obtained after appropriate chemical modifications. Similar quantum yields for the production of ROS than those shown by traditionally used organic dyes have also been reported for some transition metal 46 and might suffer from attenuated fluorescence and insufficient ROS generation.…”

Type I Photosensitizers Revitalizing Photodynamic Oncotherapy

“…Normally, traditional molecular photosensitizers have a poor triplet state quantum yield, and heavy atoms (e.g., Br and I) are often employed to enhance their ISC process. [ 111 ] Although the ROS generation efficiency can be significantly improved, the concerns about their “dark toxicity” might increase as well. [ 112 ] Therefore, developing photosensitizers without heavy atoms remains a huge challenge.…”