pH-triggered hydrophility-adjustable fluorescent probes for simultaneously imaging lipid droplets and lysosomes and the application in fatty liver detection

• DOI: 10.1016/j.bios.2024.116084
• Publication Date: 2024-02-02T00:42:21Z
• Authors: Shining Wu; Xuechen Li; Mingyang Zhou; Yuezhi Cui; Wenli Wu; Jiantao Ping; Xuezu Guo; Qiongzheng Hu

To study the collaboration between lipid droplets (LDs) and lysosomes, and the lipid change in nonalcoholic fatty liver disease (NAFLD), herein two pH-triggered hydrophility-adjustable fluorescent probes (LD-Lyso and LD-Lyso 1) are designed. The mechanism is based on cyclization and ring-opening with thorough consideration of pH and hydrophilic differences between LDs and lysosomes. Both of the two probes exist in ring-opening form and emit red fluorescence in acidic environment, while they exist in cyclized form and the emission is blueshifted in alkaline environment due to reduced conjugate planes. Moreover, LD-Lyso exhibits near infrared fluorescence at 740 nm under ring-opening form, which facilitates further cell, tissue, and in vivo imaging. The cell imaging results show that LD-Lyso can simultaneously target LDs and lysosomes by two different colors. Impressively, LD-Lyso cannot only detect NAFLD tissues from the normal tissue, but also distinguish different degrees of NAFLD tissues and mice, which provides a very promising tool for timely diagnosis of early NAFLD.