Encapsulation of diiodo-BODIPY in sodium dodecyl sulfate stabilized cellulose acetate capsules for enhanced singlet oxygen production in aqueous solution

Abstract

As drug delivery vehicles, polymeric capsules have become highly versatile structures to protect the active substrate from degradation, improve biocompatibility, and provide controlled release. In particular, encapsulation could become an efficient technique to implement these materials in physiological media if the active substrate is an insoluble compound in an aqueous solution. Herein, an iodinated BODIPY derivative as a photosensitizer (PS) was encapsulated in a cellulose acetate (CA) polymer via a precipitation method with 50.8–71.8 % of encapsulation efficiency to enable the singlet oxygen production (1O2) in aqueous media. The prepared PS/CA capsules were stable for 10 days in PBS buffer with PdI values between 0.264–0.698 and produced 1O2 under 532 nm LED light efficiently. This work discusses the size effects of PS-loaded CA capsules on stability in solution, photophysical property, encapsulation efficiency, thermal stability, leakage behavior, and PDT activity. Additionally, under different UV light doses, the 1O2 generation of the PS/CA capsules were studied systematically.