An exploration of new avenues regarding deep tissue penetration and highersinglet oxygen efficiencies: novel near-IR photosensitizers for photodynamictherapy

Abstract

A series of novel BODIPY-bearing electron-withdrawing groups at the meso position are reported here. According to the optical measurements, it may be clearly seen that the introduction of electron-donating groups into 3,5-positions and the presence of electron-withdrawing groups at the meso position of the BODIPY core resulted in spectacular bathochromic shifts (up to~304 nm), and the projected photosensitizers had absorption bands in the therapeutic window of the electromagnetic spectrum (600-900 nm). The absorption maxima of compounds 4, 5, 6, and 7 were at 886 nm, 890 nm, 760 nm, and 761 nm, respectively. The singlet oxygen generation experiments revealed that compounds 6 and 7, with high singlet oxygen quantum yields (0.52 and 0.93, respectively), were excellent and promising candidates for photodynamic therapy. The singlet oxygen quantum yield of 0.93 was the highest reported value so far for BODIPY-based photosensitizers.

Exploring the photocatalytic and photodynamic effects of BODIPY-linked titanium dioxide nanoparticles

“…All of these are considered effective PS agents for generating 1 O 2 [ 9 ]. Besides these types of PSs, the heavy atom-incorporated BODIPY (boron-dipyrromethene) molecule is also known for its excellent 1 O 2 generation under proper light excitation [ 10 – 13 ]. Additionally, BODIPY exhibits outstanding photophysical properties, including a high fluorescence quantum yield ( φ > 70%), a high absorption coefficient ( ɛ > 50,000), intense fluorescence emission in the range of 510–800 nm, and high photostability [ 14 , 15 ].…”