Vicinal diaminobenzoacridine used as the fluorescent probe for trace nitric oxide determination by flow injection spectrofluorimetry and macrophage cells imaging

Based on a photoelectron transfer (PET) mechanism, vicinal diaminobenzoacridine (VDABA), a fluorescent probe for the determination of trace amounts of nitric oxide radical in biological sample, was synthesized and characterized by elemental analysis, IR, 1H NMR and 13C NMR spectrum. Combining a flow injection with spectrofluorimetry, a high-throughput method for detecting NO was obtained, which was successfully applied to the determination of NO in the human serum. The proposed method was simple, rapid, precise and automatic. Under optimum conditions, the linear calibration range was from 1.1 × 10−7 to 5.0 × 10−6 M and the detection limit was 3.1 × 10−8 M. Furthermore, the probe could make cell-derived NO “visible” by using confocal laser scanning microscope.