An Activatable Afterglow/MRI Bimodal Nanoprobe with Fast Response to H2S for In Vivo Imaging of Acute Hepatitis

Abstract Accurate detection of hepatic hydrogen sulfide (H 2 S) to monitor H 2 S‐related enzymes’ activity is critical for acute hepatitis diagnosis, but remains a challenge due to the dynamic and transient nature of H 2 S. Here, we report a H 2 S‐activatable near‐infrared afterglow/MRI bimodal probe F1 ‐GdNP, which shows an “always‐on” MRI signal and “off‐on” afterglow signal toward H 2 S. F1 ‐GdNP shows fast response, high sensitivity and specificity toward H 2 S, permitting afterglow imaging of H 2 S and evaluation of cystathionine γ‐lyase (CSE)’s activity in living mice. We further employ the high spatial‐resolution MRI signal of F1 ‐GdNP to track its delivery and accumulation in liver. Importantly, F1 ‐GdNP offers a high signal‐to‐background ratio (SBR=86.2±12.0) to sensitively report on the increased hepatic H 2 S level in the acute hepatitis mice via afterglow imaging, which correlated well with the upregulated CSE activity in the liver, showcasing the good potential of F1 ‐GdNP for monitoring of acute hepatitis process in vivo.