Development of iridium(III) phosphorescent probe for hypochlorous acid detection in macrophages cells and cancer cells co-culture system and application in inflamed mouse model

Abstract

Macrophages infiltrated in tumor microenvironment (TME) were found to play vital roles in immune responses and tumor development. In the process of immune, macrophages could produce pro-inflammatory mediators including ROS. Thus, targeting macrophages related ROS and distinguishing macrophages and cancer cells in one or more types of tumor and tumor microenvironments is extremely important and necessary to better understand tumor-associated macrophages (TAMs) functions and provide new insights into macrophage-centred therapeutic. Herein, we developed two unique Ir(III) probes, Ir1 and Ir2, for HOCl detection. Because of the dual protection of C^N ligand, Ir2 exhibits high sensitivity and selectivity in the present of HOCl. Therefore, Ir2 can be employed to detect HOCl in flow cytometry and image exogenous and endogenous HOCl in mitochondria. Importantly, Ir2 was applied to distinguish macrophages cells and cancer cells in TAMs by flow cytometry. Moreover, Ir2 is applicable in staining five kinds of organs of mouse tissues and monitoring HOCl generation in the LPS-stimulated inflammation of mouse model with two-photon microscopy (TPM).