Reactive probe for hydrogen sulfite: Good ratiometric response and bioimaging application

4-(1H-Phenanthro[9,10-d] imidazol-2-yl) benzaldehyde (P-1) was prepared as a new ratiometric optical probe for hydrogen sulfite. Upon the addition of HSO3-, it displayed large emission wavelength shift (Delta lambda = 120 nm) and the detection limit was determined to be as low as 2 mu M. In addition to its high selectivity for hydrogen sulfite rather than other common anions, P-1 was successfully applied to the detection of hydrogen sulfite in HeLa cells with ratiometric fluorescent methods. (C) 2013 Elsevier B.V. All rights reserved.