Immobilization of ALA‐Zn^II Coordination Polymer Pro‐photosensitizers on Magnetite Colloidal Supraparticles for Target Photodynamic Therapy of Bladder Cancer

Abstract

5-Aminolevulinic acid (ALA) is a widely used photodynamic therapy (PDT) prodrug in the clinic. It can be metalized to the photosensitizer PpIX, which produces toxic singlet oxygen to kill cancer cells upon visible light irradiation. Herein, a core/shell-structured vehicle is designed to comprise magnetite colloidal supraparticles (MCSPs) as cores and ALA-Zn(II) coordination polymers as shells (Fe3O4@ALA-Zn(II) ) for target pro-photosensitizer delivery. The coordination polymers with 2D layered structures are locally deposited on the MCSPs by the complexation of the ALA and Zn(II) ions, and are readily controlled by varying the feed precursors and reaction temperatures. The maximum conjugated ALA amount is up to 17%. The Fe3O4@ALA-Zn(II) microspheres exhibit pH-sensitive release of ALA in acidic environment and rapid magnetic responsiveness. Cytotoxicity results demonstrate that Fe3O4@ALA-Zn(II) shows a significant inhibitory effect to T24 cells and is nontoxic to 293T normal cells as exposed to the 630 nm visible light for a very short time, which may due to the selective accumulation of ALA-induced PpIX in T24 cancer cells. Compared to the ALA used alone, the coordination polymer form is more efficient because of the bioactivity of incorporated Zn ions despite underlying the same apoptosis mechanism as ALA agent.

Upconversion nanoparticle-mediated photodynamic therapy induces autophagy and cholesterol efflux of macrophage-derived foam cells via ROS generation

“…5, 6, 7 Although PDT has been applied clinically to treat diseases, its notable drawback is that the effect of the traditional photosensitizer chlorin e6 (Ce6) has a shallow depth. 8, 9 In this study, we combined the widely used photosensitizer Ce6 with silica nanoparticles, which have high hydrophilicity, good biocompatibility and favorable optical properties, to form a UCNPs-Ce6 complex.…”

Controllable Photodynamic Therapy Implemented by Regulating Singlet Oxygen Efficiency

“…88 ALA could selectively accumulate in tumorous tissues and be metalized to the PS PpIX for producing 1 O 2 after the visible light irradiation. In this PS (Fe 3 O 4 @ALA‐Zn II ), the ALA release could be triggered by a small pH variation (pH 7.4 to 6.0 and 5.0).…”

“…Instead of the most PS in the core part, Guo et al confined the pH sensitive PS, 5‐aminolevulinic acid Zn(II) coordination polymer (ALA‐Zn II , 19 ) in the shell part, and magnetite colloidal supraparticles (Fe 3 O 4 ) in the core part ( Figure ) . ALA could selectively accumulate in tumorous tissues and be metalized to the PS PpIX for producing 1 O 2 after the visible light irradiation.…”

Mucoadhesive Cationic Polypeptide Nanogel with Enhanced Penetration for Efficient Intravesical Chemotherapy of Bladder Cancer

“…These well‐designed drug carriers possess unique physical properties, including improved tissue mucoadhesiveness and permeability, colloidal stability, sustained drug delivery ability, as well as a relatively low cost 9, 10, 11, 12. However, there are still several deficiencies that limit the clinical applications.…”