| Necleophilic and elimination reactions could take place between hydrazine derivatives and carbonyl compounds to generate hydrazone with-NHNH2structure. Hydrazone and its derivatives with unique biological activities and optical propoties attract great attentions in the fileds of biology, pharmaceutics, functional materials and analytical chemistry. However, few researchers have employed the above interaction for analysis purpose. Then, this thesis tries to apply it to hydrochloric acid hydralazine and formaldehyde analysis, and to preliminarily investigate the reaction mechanism.1. Hydrazine derivatives could react with ninhydrin to generate a colorful product containing-NHN=CH-groups, that is hydrazone, which could carry out at room temperature with very slow step. In pH6.2PB buffer, it was found that the above reaction could get faster if boric acid catalyzes it, which was applied to rapid determination of hydralazine. Under the optimum reaction conditions, the increment of absorbance(436nm) was directly proportional to the concentration of hydralazine hydrochloride in the ranges of0.50～40μmol/L, with the detection limits of0.18μmol/L. Furthermore, the reaction mechanism was discussed based on the boric acid catalyzed reaction.2. The interaction of hydrazine derivatives containing Rhodamine B with formaldehyde generates hydrazone, leading to the opening of oxygen miscellaneous anthracene ring to induce the color changes from colorless to red and the enhancement of fluorescence. In pH5.0NaAC-HAc buffer, the fluorescence enhancement was directly proportional to the concentration of formaldehyde in the ranges of4.0～60ppm, the linear equation is:F/F0=1.415+0.0581c(r=0.9948). Moreover, using the change of color, Nafion film was employed as the substrate to develop a portable test paper for visualized analysis, in pH8.0Tris-HCl buffer, the composite film was used to detect formaldehyde in the ranges of0.50～100ppm. |
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