RESUMEN
A fluorescence quenching method was established for the determination of H2 S in intestinal perfusate by optical fiber sensing technology combined with micro sequential injection lab_on_valve (μSIA_lov). In the experiment, 100 μL of 0. 1 mol/L NaOH was used as the carrier, and 50 μL of 5. 0×10-5 mol/L fluorescein mercury and 50 μL of sample were selected for the determination. The detection flow rate at the flowcell was 25 μL/s. According to H2 S quenching fluorescence at 521 nm, the concentration of H2 S in the sample was determined. The detected concentration range of H2S was 5. 0×10-6-8. 0×10-5 mol/L, and the detection limit was 5. 4×10-7 mol/L. Detection result of H2S in intestinal perfusion was 3. 8×10-5 mol/L with 3. 1% RSD (n=3). This method can be used for the determination of H2S effectively in the samples, which lay the foundation for real_time online measurement of H2 S in biological samples.