Low-Dose NIR-II Preclinical Bioimaging Using Liposome-Encapsulated Cyanine Dyes.
Duyang GaoZichao LuoYang HeLixiang YangDehong HuYongye LiangHairong ZhengXiaogang LiuZonghai ShengPublished in: Small (Weinheim an der Bergstrasse, Germany) (2023)
Fluorescence imaging in the second near-infrared window (NIR-II, 1000-1700 nm) provides a powerful tool for in vivo structural and functional imaging in deep tissue. However, the lack of biocompatible contrast agents with bright NIR-II emission has hindered its application in fundamental research and clinical trials. Herein, a liposome encapsulation strategy for generating ultrabright liposome-cyanine dyes by restricting dyes in the hydrophobic pockets of lipids and inhibiting the aggregation, as corroborated by computational modeling, is reported. Compared with free indocyanine green (ICG, an US Food and Drug Administration-approved cyanine dye), liposome-encapsulated ICG (S-Lipo-ICG) shows a 38.7-fold increase in NIR-II brightness and enables cerebrovascular imaging at only one-tenth dose over a long period (30 min). By adjusting the excitation wavelength, two liposome-encapsulated cyanine dyes (S-Lipo-ICG and S-Lipo-FD1080) enable NIR-II dual-color imaging. Moreover, small tumor nodules (2-5 mm) can be successfully distinguished and removed with S-Lipo-ICG image-guided tumor surgery in rabbit models. This liposome encapsulation maintains the metabolic pathway of ICG, promising for clinical implementation.
Keyphrases
- fluorescence imaging
- photodynamic therapy
- low dose
- clinical trial
- drug administration
- aqueous solution
- high resolution
- randomized controlled trial
- healthcare
- ionic liquid
- magnetic resonance
- drug delivery
- signaling pathway
- computed tomography
- coronary artery bypass
- climate change
- risk assessment
- acute coronary syndrome
- fatty acid