Zwitterionic near infrared fluorescent agents for noninvasive real-time transcutaneous assessment of kidney function† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c6sc05059j Click here for additional data file.

We developed novel zwitterionic near infrared (NIR) fluorescent agents (ABZWCY-HPbCD and AAZWCYHPbCD), which exhibit favorable hydrophilicity, low plasma protein binding, high stability and nontoxicity. These attractive characteristics ensure that they are excreted rapidly, without any skin accumulation or metabolism in vivo. More importantly, zwitterionic HPbCD based agents can be efficiently filtrated by the glomerulus and completely excreted through the kidneys into urine without reabsorption or secretion in the kidney proximal tubule. Relying on these novel zwitterionic NIR agents and a transcutaneous device, we demonstrate a rapid, robust and biocompatible approach for assessing kidney function in rat models of both healthy rats and those with kidney disease, without the need for time-consuming blood/urine sample preparation. Our work provides a promising tool for in vivo realtime non-invasive kidney function assessment in preclinical applications.