FLUORESCENT MICROSCOPIC DETERMINATION OF GATIFLOXACIN IN MILK, INJECTION, HUMAN URINE AND RABBIT SERUM SAMPLES BY SELF-ORDERED RING TECHNIQUE ON GLASS SLIDES SUPPORT

摘要

A simple and sensitive self-ordered ring (SOR) technique, which was based on the capillary effect of solvent on a hydrophobic glass slide, was successfully applied to the determination of gatifloxacin in milk, injection, human urine and rabbit serum samples. In a medium of pH 3.20 (HAc-NaAc) with the aid of polyvinyl alcohol)-124 (PVA-124), when 0.50 mu L aluminum-sensitized gatifloxacin was dropped on glass slide with dimethyl dichlorosilane (DMCS) pretreated, a typical fluorescent SOR with diameter(2R) of the ring less than ca. 1.77 mm and the belt width (2 delta) less than 29.3 mu m can be obtained. The solute on the ring belt had strong fluorescence. Data of the imaged SOR showed that the gatifloxacin molecule across the SOR belt section follows a Gaussian distribution. The assay showed that when the droplet volume is 0.1 mu L, the SOR method coued be used to determine gatifloxacin in the range of 5.61 x 10~(-14)~ 1.50 x 10~(-12)mol/ring(5.61 x 10~(-8)~1.50 x 10~(-5) M) and the limit of determination (LOD) reached 5.61 x 10~(-15) mol/ring (5.61 x 10~(-8) M) with three-fold signal-to-noise ratio (S/N = 3).