A zwitterionic chromophore as both a biomarker-activatable optical imaging probe and a therapeutic agent for the detection and treatment of acute lung injury with bacterial infection

Abstract

Acute lung injury (ALI), often complicated by bacterial infection, poses significant challenges in diagnosis and treatment. Nitric oxide (NO) plays a key role in the pathophysiology of ALI, making it an ideal biomarker for early detection. In this study, we developed a zwitterionic chromophore, ZW–N, designed as both a biomarker-activatable imaging probe and a therapeutic agent for ALI with bacterial infection. The chromophore ZW–N integrates quaternary ammonium groups for antimicrobial activity and zwitterionic sulfonate groups to enhance biocompatibility and water solubility. Built on a flexible propanyl linker that couples two heptamethine cyanine dyes, ZW–N enables biomarker-responsive dual-modal imaging via optoacoustic (OA) imaging and near-infrared second-window (NIR-II) fluorescence imaging. Moreover, the chromophore ZW–N demonstrates therapeutic efficacy when combined with the clinically used antioxidant N-acetylcysteine (NAC) to treat ALI with bacterial infection. This dual-functional chromophore offers a promising platform for non-invasive, real-time monitoring of ALI, providing significant potential for improved detection and a more effective treatment strategy.