Coupling probiotics with 2D CoCuMo-LDH nanosheets as tumor microenvironment-responsive platform for precise NIR-II photodynamic therapy.

Photodynamic therapy (PDT) has become a promising cancer treatment approach with superior advantages. However, it remains a ground challenge to develop tumor microenvironment (TME)-responsive photosensitizers (PSs) for tumor-targeting precise PDT. Herein, we report the coupling Lactobacillus acidophilus probiotics with 2D CoCuMo-layered double hydroxide nanosheets (LA&LDH) as a TME-responsive platform for precise NIR-II PDT. The CoCuMo-LDH nanosheets loaded on LA can be transformed from crystalline into amorphous one through etching by the LA metabolite-enabled low pH and over-expressed glutathione. The TME-induced in-situ amorphization of CoCuMo-LDH nanosheets can boost its photodynamic activity for singlet oxygen ( 1 O 2 ) generation under 1270 nm laser irradiation with the relative 1 O 2 quantum yield of 1.06, which is the highest among previously reported NIR-excited PSs. In vitro and in vivo assays prove that the LA&LDH can effectively achieve complete cell apoptosis and tumor eradication under 1270 nm laser irradiation. This study proves that the probiotics can be used as a tumor-targeting platform for highly efficient precise NIR-II PDT. This article is protected by copyright. All rights reserved.