A water-soluble photo-induced NO donor with high fluorescence quantum yield and the real-time monitoring of its controlled NO release in living cells and zebrafishes

In this work, a water-soluble photo-induced NO donor CNA-NO was deveolped to increase the local concentration of nitric oxide in human body. The 6-(butylamino)-3,4-dihydronaphthalen-1(2H)-one was chosen to replace the aminoacetophenone in the common design of rhodamine to form the red fluorophore CNA and the N-nitroso group was employed as the fluorescence quenching group of fluorophore CNA, which formed the NO donor CNA-NO. The cyclohexyl group in naphthalenone was introduced to limit the rotation of the free benzene in this photoreleaser and the energy of the donor was sent in the form of fluorescence, which could enhance the fluorescent signals of CNA-NO and was helpful to monitor and control the release of nitric oxide accurately. Upon the irradiation, the fluorescence of CNA-NO enhanced more than 78-fold and the fluorescence quantum yield changed from 0.79% to 20.31%. The nitric oxide releasing yield was calculated to be 58.6%. The appropriate release time of 40 min and nitric oxide release in a wide pH range including physiological environment were helpful to control the increased concentration of nitric oxide accurately. At last, good biocompatibility ensured the success of the controllable nitric oxide release in living cells and zebrafishes. [Display omitted] •A water-soluble and photo-induced NO donor CNA-NO was synthesized.•The fluorescence of CNA-NO enhanced more than 78-fold upon the irradiation.•CNA-NO was applied for monitoring of NO release in living cells and zebrafishes.