吩噻嗪在十二烷基硫酸钠/苯甲醇/水微乳液中的定位

采用循环伏安法和荧光猝灭法研究了吩噻嗪（PTZ）在十二烷基硫酸钠（SDS）/苯甲醇（BA ）/ 水（H2O）微乳液中的定位.结果表明,吩噻嗪在十二烷基硫酸钠/苯甲醇/水体系微乳液中位于微乳液膜相中靠近表面活性剂极性头基的一侧,PTZ分子中的S原子和N原子均可朝向表面活性剂的极性头基.

The Location of Phenothiazine in SDS/BA/H2O Microemulsion

The location of phenothiazine in SDS/BA/H2O microemulsion was investigated by cyclic voltammetric and fluorescence quenching method.In O/W microemulsion,phenothiazine has two oxidation peaks.Because the peak potentials are independent of the sweep rate ( Fig.1 ) and all the peak currents are proportional to the square root of the potential sweep rate ( Fig.2 ),the electrochemical process for phenothiazine is reversible.According to the peak separation between the peak potentials in the positive and negative scans and the Nernstian equation,the above cyclic voltammetric characteristics for all peaks are of one - electron process.Since the process of the radical cation PTZ＋•losing an electron to form PTZ2＋ needs much more energy (≈0.4 V ) and there is only about 0.13 V between the two peaks ( table 1,Fig.1 ),the two peaks are both produced by the process of PTZ molecule losing an electron.In PTZ molecules,there are two polar groups with the S and N atoms as center,respectively.Thus,the phenothiazine molecules exist in the membrane phase with its N atom or S atom extended toward the polar head in the O/W microemulsion.Further experiments found that the fluorescence quenching of anthracene by PTZ in the W/O microemulsion is rather more similar to that in the O/W microemulsion than in pure benzyl alcohol.So,the location of PTZ in the W/O microemulsion is the same as in the O/W microemulsion,i.e.,in the inner side of the membrane phase of the W/O microemulsion.