Fluorination Chemistry Enhances NIR-II Fluorescence of Polymer Dots for Quantitative Brain Tumor Imaging.

Fluorination Chemistry Enhances NIR-II Fluorescence of Polymer Dots for Quantitative Brain Tumor Imaging. Angew Chem Int Ed Engl. 2020 Aug 07;: Authors: Liu Y, Liu J, Chen D, Wang X, Zhang Z, Yang Y, Jiang L, Qi W, Ye Z, He S, Liu Q, Xi L, Zou Y, Wu C Abstract Fluorescent probes in the second near-infrared region (NIR-II, 1000~1700 nm) have resulted in unprecedented imaging performance. Here, we describe a fluorination strategy in semiconducting polymers for development of highly bright NIR-II probes. Notably, tetrafluorination yielded a fluorescence QY of 3.2% for the polymer dots (Pdots), over 3-fold enhancement as compared to non-fluorinated counterparts. The fluorescence enhancement was attributable to nanoscale fluorous effect in the Pdots that maintained the molecular planarity and minimized the structure distortion between the excited state and ground state, thus reducing the nonradiative relaxations. Followed by through-skull and through-scalp imaging of the brain vasculature of live mice, we quantitatively analyzed the vascular morphology of transgenic brain tumors in terms of the vessel lengths, vessel branches, and vessel symmetry, which showed statistically significant differences from the wild type animals. The bright NIR-II Pdots achieved by fluorination chemistry provide insightful information for precise diagnosis of the malignancy of the brain tumor. PMID: 32767727 [PubMed - as supplied by publisher]
Source: Angewandte Chemie - Category: Chemistry Authors: Tags: Angew Chem Int Ed Engl Source Type: research