A novel fiber optic biosensor for nitric oxide determination based on vicinal diaminobenzozcridine fluorescent probe

A novel fiber optic biosensor for the determination of nitric oxide based on vicinal diaminobenzozcridine (VDABA) fluorescent probe was designed and fabricated. The reaction conditions between VDABA and NO, which include concentration of VDABA, temperature and pH, were studied in-depth. The sensitivity of VDABA for NO detection under the optimum conditions and its optical properties were also investigated. The fluorescence responses were concentration-dependent and a good linear relationship (R 2 =0.9863) was observed over the range 1.8×10 -6 to 9×10 -6 mol/L NO, the regression equation was F = 3.8889[NO] (mol/L)+217.2. Besides, a complex sensitive film embedding VDABA in cellulose acetate (CA) was prepared, and a fiber optic NO biosensor was fabricated using this film. Then the change of fluorescence phase shift of this biosensor was studied preliminarily by means of the lock-in technology.