The Interaction Between The Organized Assembly Of The Cephanone Surfactant Molecules

1. The Effects of Cephanone on the Structural Characters of CTAB MicellesThe effects of cephanone on the first critical micelle concentration (cmc1) and the second critical micelle concentration (cmc2) of cationic surfactant Hexadecyltrimethylammonium bromide (CTAB) was studied by the methods of conductivity and fluorescence polarization. The aggregation number of CTAB micelles and the distribution coefficient of cephanone between CTAB micelle and water were studied by the methods of the steady state fluorescence and UV spectra, respectively. The results show that with the increasing cephanone concentration, cmc1 and cmc2 of CTAB micelle both increase, whereas the aggregation number of CTAB micelles and the viscosity of CTAB micelle system both decrease, the above results may be related to the interaction between cephanone and CTAB and the distribution of cephanone in CTAB micelle.2. The Hydrotrope and Hydrotrope-Solubilization Action ofCephanone in CTAB/n-C5H11OH/H2O SystemThe effects of cephanone on the phase behavior of CTAB/n-C5H11OH/H2O system have been studied by the method of phase diagram. The structure of microemulsion and the location of cephanone in the microemulsion and lamellar liquid crystal have been determined. The results show that cephanone can increase the solubilities of cationic surfactant CTAB, which shows the hydrotrope action of cephanone. Cephanone also shows the hydrotrope-solubilization action which makes the solubility of n-C5H11OH in water and that of water in n-C5H11OH increase, and the solubilization amount of n-C5H11OH in O/W microemulsion and that of water in W/O microemulsion both increase. The mechanism of the hydrotrope-solubilization action of cephanone may be that the location of cephanone in the interphase of microemulsion causes the stability of O/W and that of W/O microemulsion enhanced and the solubilization amount of n-C5H11OH in O/W microemulsion and that of water in W/O microemulsion increased.The location of cephanone in the amphiphilic bilayer of the lamellar liquid crystal makes the stability of the lamellar liquid crystal decrease and the lamellar liquid crystal region reduce, and leads to the structural transition from lamellar liquid crystal to the bicontinuous structure.3. The Effects of CTAB/n-C5H11OH/H2O System on the Release of CephanoneThe release of cephanone in water, CTAB micelles and CTAB/n-C5H11OH/H2O microemulsions were studied by Uv-vis absorption spectroscopy. The distribution coefficient and the location of cephanone in CTAB micelle and CTAB/n-C5H11OH/H2O microemulsion, and the effect of the composition of microemulsions on the release rate were studied. The results show that CTAB micelles and the microemulsions formed by CTAB/n-CsH11OH/H2O can reduce the release rate of cephanone due to the location of cephanone in the palisade of the micelle and microemulsion. The release rate of cephanone decreases with the increasing CTAB content and it first increases then decreases with the increasing n-pentanol content.4. The Effects of CTAB/n-CsHnOH/HzO System on the Stability of CephanoneThe hydrolysis of cephanone in water, CTAB micelle and O/W microemulsions of CTAB/n-CsHnOH/FbO was studied by Uv-vis absorption spectroscopy. The change of pH in different hydrolysis system and the effect of composition of microemulsion on the hydrolysis were studied. The results show that the pH increased first and then reduced to the minimum with the hydrolysis. Compared with water, CTAB micelles and the O/W microemulsions formed by CTAB/n-C5H11OH/H2O inhibited the hydrolysis.