Nanocaging Rose Bengal to Inhibit Aggregation and Enhance Photo-induced Oxygen Consumption^†

Area of Science:

• Biomaterials Science
• Photochemistry
• Medical Applications

Background:

• Photosensitized crosslinking of proteins is vital for medical applications like wound healing and tissue repair.
• Rose Bengal (RB) is a common photosensitizer but its aggregation at high concentrations reduces efficiency.
• Aggregation of RB decreases singlet oxygen yield, hindering effective protein crosslinking.

Purpose of the Study:

• To investigate the use of nanocages to sequester RB and inhibit its aggregation.
• To enhance the photosensitization efficiency of RB for medical applications.
• To evaluate the impact of nanocaging on RB's photobleaching and oxygen consumption kinetics.

Main Methods:

• Tested cucurbituril and cyclodextrin nanocages for RB sequestration.
• Investigated hydroxypropyl-functionalized cyclodextrins for their efficacy in inhibiting RB aggregation.
• Analyzed oxygen consumption and photobleaching rates of RB/cyclodextrin solutions under LED light.

Main Results:

• Hydroxypropyl-functionalized cyclodextrins were most effective at inhibiting RB aggregation.
• Oxygen consumption rates increased by 58-80% at 100 μm RB and 200-300% at 1 mm RB with cyclodextrin nanocages.
• Photobleaching rates increased by ~20% and ~75% at 1 mm RB with β and γ cyclodextrins, respectively.

Conclusions:

• Nanocages can effectively minimize RB aggregation, leading to improved photosensitization.
• This approach holds promise for developing more efficient photo-medical therapies.
• Optimized RB/cyclodextrin formulations could advance tissue engineering and regenerative medicine.