Spectroscopic Study On The Interaction Of Cucurbit"n"urils With Guest Molecule

1. Synthesis, characterization of 1,10-phenanthroline derivatives and their spectroscopic study after interacted with cucurbit[n]urils(Q[n],n=6~8)Six novel 1,10-phenanthroline derivatives(G1~G6) were synthesized, and characterized by IR, 1H NMR, MS and elemental analysis.UV-Vis spectra, fluorescence spectrophotometry and 1H NMR were applied to investigate the interactions between the compounds( G1~G6) and Q[n] (n=6~8). Formation constant and inclusion ratio of all G-Q systems were determined. The results showed that G1-Q[6], G1-Q[7], G2-Q[6], G3-Q[7], G3-Q[8], G4-Q[7], G4-Q[8],G5-Q[7], G6-Q[7] and G6-Q[8] both forms a 1:1 complex, their formation constant of K were found to be 3.00×10~4, 1.86×10~4, 1.64×10~4, 1.90×10~4, 6.67×10~3, 7.00×10~4, 2.10×10~4, 1.60×10~4, 5.75×10~4 and 2.55×10~4 L/mol respectively. G2-Q[7] and G5-Q[8] form a 2:1 complex, their formation constant of K were found to be 1.01×10~3 and 0.575×10~3 L/mol respectively. The effect of pH value of media on the interaction was also studied. The experiment results revealed that Q[n](n=6~8) can selectively interact with guests (G1~G6) and form stable inclusion complexes under acidic condition.2. Spectroscopic study respectively on the interaction of berberine hydrochloride with Q[n](n=7,8), ranitidine hydrochloride with Q[n](n=7,8) and drugs release properties in vitro2.1 The interaction between berberine hydrochloride (BH) and Q[n](n=7,8) and the effect of pH value in media solution on the interaction were investigated by UV-Vis spectroscopy and fluorescence spectrophotometry. The inclusion ratio and formation constant were determined. Drug release behavior of inclusion complexes in vitro was detected by ultraviolet spectrometry. According to the experimental results, Q[7] and Q[8] were capable of interacting with BH under both acidic and alkaline conditions in solution. Q[7] formed a 2:1 complex with BH, formation constant of K was found to be 6.71×10~4L/mol. However, Q[8] formed a 1:2 complex with BH, formation constant of K was found to be 1.44×10~4 L/mol. Moreover, fluorescent sensitizing effect of Q[7] and Q[8] on BH were both observed. The release of BH was sustained since the clathrate compound was formed.2.2 UV-Vis spectroscopy and 1H NMR were performed to investigate the interaction of Q[n] (n=7,8) with ranitidine hydrochloride (RH). The effect of pH value of solution on the interaction were studied; the inclusion ratio and formation constant K were determined. Drug release behavior of inclusion complexes in vitro was detected by ultraviolet spectrometry. The results revealed that RH form a 1:1 complex with the Q[n](n=7,8). Formation constant of K was found to be 1.21×10~4 L/mol and 2.06×10~4 L/mol for RH-Q[7] and RH-Q[8] systems respectively. RH can both form inclusion complexes with Q[7] and Q[8] in acidic and neutral conditions respectively. We observed significant slow release of RH since the clathrate compound was formed.