Copper-bridged fluorescent turn-on molecular system for high-performance identification and bioimaging of carbon monoxide

Novel high-performance fluorescent strategies have always been in great demand for carbon monoxide (CO) detection and cell-imaging at room temperature, which have two sides of a coin: its high toxicity even at low concentrations and crucial role in physiological and pathophysiological processes. Herein, we constructed a copper-bridged fluorescent turn-on molecular system, Nap-BC-Cu2+, in monitoring and cell-imaging of vaporous CO at room temperature. The absence of expensive palladium salts and the capability to detect both CORM-3 and CO are two major advantages of this strategy compared to previous reports. The sensing performance of the system is exceptional, demonstrated by less than 1 s response time and high sensitivity with remarkable fluorescence enhancement. The detection limit is calculated to be as low as approximately 82 nM and ∼ 14 ppb for CORM-3 and CO vapor, respectively. Besides, the presence of potential interferences had minimal impact on the detection. Moreover, the quantitative detection of CO vapor was also realized by naked-eye observation via paper tests, which provide a low-cost portable strategy for the real-time CO detection. Furthermore, the fluorescent turn-on molecular system exhibited low cell toxicity and high cellular uptake, and was effectively utilized for imaging CO in living Hela cells. [Display omitted] A novel copper-bridged fluorescence turn-on sensing platform for high-performance recognition, cell-imaging and paper test of CO is reported. •A novel copper-bridged fluorescent turn-on molecular system was designed and constructed.•Visual and fluorescence recognition specific for both CO vapor and CORM-3 were realized.•Fast response, high selectivity and low LOD of 82 nM and ∼ 14 ppb for CORM-3 and CO vapor, respectively, were achieved.•Paper strips detection of carbon monoxide vapor with obvious fluorescence color changes was realized.•Imaging CO in living Hela cells was successfully performed.