A near-infrared-II molecular probe for early diagnosis of acute kidney injury induced by diverse etiologies

Acute kidney injury (AKI) is a clinical syndrome characterized by complex etiologies and usually lacks obvious clinical manifestations at the early stage. Compared with traditional imaging methods, optical imaging is broadly considered to be a promising technique for diagnosis of kidney dysfunction own to the merits of noninvasiveness, high sensitivity and fast feedback speed. Herein, we report a water-soluble fluorophore, PEG-TBSe, for in vivo imaging across diverse AKI models in the second near-infrared (NIR-II, 1000–1700 nm) window. Notably, PEG-TBSe possesses an ultrasmall size (~5.5 nm) that is suitable for renal clearance, allowing for comprehensive assessment of AKI severity in pre-renal, renal and post-renal models. In addition, the real-time imaging capacities of PEG-TBSe are sensitive to early changes in AKI, enabling the noninvasive identification of renal lesions earlier than common clinical assays. Overall, this study demonstrates the first NIR-II small molecular probe for the early diagnosis and evaluation of the severity of kidney dysfunction in different AKI models.