Accurate Detection of Hcy in Human Serum and Two-Photon Visualization of Atherosclerosis Using a Highly Specific Fluorescent Probe

As an important metabolic intermediate of sulfur-containingaminoacids in human body, homocysteine (Hcy) is regarded as an independentrisk factor for atherosclerotic cardiovascular disease. Therefore,real-time monitoring of the fluctuation of Hcy level is of great importancefor the early diagnosis as well as the treatment of atherosclerosis.Herein, a new two-photon (TP) fluorescent probe (RH-2) was developed via a hydrogen bond-assisted strategy, which hada high specificity for detecting Hcy over cysteine (Cys) and glutathione(GSH) in solution, cells, and tissue. Probe RH-2 wasapplied to the quantitative determination of Hcy in human serum successfully.Moreover, the two-photon fluorescence (TPF) imaging of abnormal expressionof Hcy in aortic vessels and liver of atherosclerotic model mice werefulfilled by RH-2. Therefore, probe RH-2 can be served as a potential tool to understand the function ofHcy in atherosclerosis, supplying a clinical promise for the earlydiagnosis of atherosclerosis (AS).

Automated summary

As a key metabolic intermediate for sulfur-containing amino acids, homocysteine (Hcy) is considered an independent risk factor for atherosclerotic cardiovascular disease. Therefore, real-time monitoring of Hcy levels is crucial for early diagnosis and treatment of atherosclerosis. A new two-photon fluorescent probe (RH-2) was developed using a hydrogen bond-assisted strategy, demonstrating high specificity for detecting Hcy in various biological samples. RH-2 successfully quantitatively determined Hcy in human serum and enabled two-photon fluorescence imaging of abnormal Hcy expression in atherosclerotic model mice, offering potential clinical applications for early diagnosis of atherosclerosis.