Cellular Trojan horse based polymer nanoreactors with light-sensitive activity.

Area of Science:

• Nanotechnology
• Biomaterials Science
• Photochemistry

Background:

• Stimulus-sensitive nanodevices offer potential for advanced diagnostics and therapeutics.
• On-demand generation of reactive oxygen species (ROS) is crucial for targeted therapies.

Purpose of the Study:

• To develop and optimize light-sensitive nanoreactors for controlled ROS generation.
• To evaluate the efficacy of these nanoreactors in cancer cells for photodynamic therapy (PDT).

Main Methods:

• Encapsulation of Rose Bengal-bovine serum albumin (RB-BSA) photosensitizer within polymer vesicles (PMOXA-PDMS-PMOXA and PNVP-PDMS-PNVP).
• Optimization of nanoreactor size, stability, and encapsulation efficiency using light scattering, TEM, and UV-vis spectroscopy.
• Assessment of ROS generation and diffusion via electron spin resonance (ESR) spectroscopy.
• Evaluation of cellular uptake and phototoxicity in HeLa cells.

Main Results:

• Different block copolymers influenced encapsulation efficiency and cellular uptake.
• Optimized nanoreactors demonstrated efficient, illumination-controlled ROS production.
• ROS diffusion through the polymer membrane was dependent on copolymer molecular weight.
• Nontoxic nanoreactors induced HeLa cell death under PDT conditions, acting as a 'Trojan horse'.

Conclusions:

• Light-sensitive nanoreactors provide a stable and efficient platform for on-demand ROS generation.
• These nanoreactors show significant potential for precise spatiotemporal control in photodynamic therapy applications.
• The 'Trojan horse' mechanism enables targeted cell killing with minimal off-target effects.