Development of a red-light emission hypoxia-sensitive two-photon fluorescent probe for in vivo nitroreductase imaging. Issue 3 (19th December 2018)

• Record Type: Journal Article
• Authors: Gebremedhin, Kalayou Hiluf; Li, Yaming; Yao, Qichao; Xiao, Ming; Gao, Fengli; Fan, Jiangli; Du, Jianjun; Long, Saran; Peng, Xiaojun
• Is Part Of: Journal of materials chemistry. Volume 7:Issue 3(2018)
• Page Start: 408
• Page End: 414
• Publication Date: 2018-12-19
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Biomedical materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c8tb02635a
• Languages: English
• ISSNs: 2050-750X

Abstract

Abstract : A red-light emission nitroreductase-activatable two-photon fluorescent probe, namelyNRP, was developed for monitoring of degree of hypoxia in cells and in vivo nitroreductase imaging. Abstract : The overexpression of nitroreductase (NTR ) in hypoxia has been recognized as a biomarker of highly aggressive disease, and the development of a hypoxia-sensitive two-photon (TP) bioimaging probe with both excitation and emission wavelengths in the red-light region provides favorable deep-tissue imaging with a low background fluorescence signal. Although quite a few TP hypoxia-sensitive fluorescent probes have been reported forNTR detection, their short emission wavelength (<550 nm) limits their application. Herein, we report a red light emissive TP hypoxia-sensitive turn-on probe (NRP ) by employing Nile Red as a red-emitting fluorophore and p -nitrobenzene as anNTR recognition group with improved sensitivity. TheNRP probe showed obvious strong red-fluorescence enhancement in the presence ofNTR and high selectivity towardNTR in aqueous solution. Our in vitro experimental results illustrated that theNRP loaded tumor cells treated under hypoxia display remarkably strong fluorescence in both OP and TP microscopy at 655 nm with 45-fold enhancement, which affords deep-tissue penetration ability. TheNRP probe was also successfully applied for imagingNTR in liver tissue slices and a 4T1-bearing mice model, which is important for bioimaging applications.