采用紫外吸收光谱法检测十二烷基二苯醚二磺酸钠（SLDED）与十二烷基磺酸钠(SDS)二元复合体系中SLDED的含量。 结果表明, 在复合溶液中SDS能增强SLDED的吸光度, 加入0.500 mmol·L-1复合组分SDS后, 0.500 mmol·L-1 SLDED的吸光度由0.631增加至0.682, 增幅达8.1%; 同时SDS还可以明显降低SLDED在水溶液中的表观临界胶束浓度（cmc）, 当SDS的浓度从0增加至0.500 mmol·L-1时, SLDED的表观cmc由1.12 mmol·L-1降低至0.702 mmol·L-1。 研究结果还表明, 羟丙基-β-环糊精（HP-β-CD）能有效消除SDS对SLDED紫外光谱的干扰, 加入1.000 mmol·L-1HP-β-CD后, 0.500 mmol·L-1 SLDED与0.500 mmol·L-1 SDS/0.500 mmol·L-1 SLDED复合溶液在281 nm处的吸光度分别为0.796和0.798, 相差仅0.3%, 远低于不添加HP-β-CD时的增幅。 在SLDED/SDS复合溶液中, SLDED形成胶束的标准摩尔吉布斯函变ΔγGθm随HP-β-CD浓度的增大而增加, 当HP-β-CD浓度由0分别增加至0.400, 0.800及1.200 mmol·L-1时, SLDED形成胶束过程的ΔγGθm由-41.098 kJ·mol-1分别增大至-39.833, -39.488和-38.184 kJ·mol-1, 表明了相比于形成胶束结构, SLDED分子优先选择与HP-β-CD形成包结物。 Job’s实验表明SLDED/HP-β-CD包结物中SLDED与HP-β-CD按物质的量比1∶2进行包结。 按包结比1∶2加入HP-β-CD后, 紫外光谱法能够准确检测SLDED/SDS复合水溶液中SLDED的含量, 方法的回收率为100.8%~101.4%。 FTIR及1H-NMR表征表明, SLDED分子进入HP-β-CD分子空腔并形成了包结物, 是HP-β-CD消除SDS干扰的本因。

Ultraviolet absorption spectrophotometry was applied to the determination of sodium lauryl diphenyl ether disulfonate (SLDED) in SLDED and sodium dodecyl sulfonate (SDS) complex systems. The results indicated that the existence of SDS not only can improve the ultraviolet absorption intensity of SLDED but also can greatly decrease the apparent critical micelle concentration values of SLDED in aqueous solution. With the addition of 0.500 mmol·L-1 SDS, the ultraviolet absorption intensity of SLDED increased from 0.631 to 0.682, with an increase of 8.1%. In addition, the apparent critical micelle concentration values of SLDED reduced from 1.12 to 0.702 mmol·L-1 when the concentrations of SDS respectively increased from 0 to 0.500 mmol·L-1. The results also showed that the interference of SDS on the ultraviolet absorption intensity of SLDED could be greatly reduced by HP-β-CD. With the addition of 1.000 mmol·L-1 HP-β-CD, the ultraviolet absorption intensity of 0.500 mmol·L-1 SLDED increased from 0.796 to 0.798, with an increase of only 0.3%, much lower than the increase without HP-β-CD. SLDED molecules were more likely to form inclusion complexes with HP-β-CD rather than micelles. Thus, the standard molar Gibbs free energy for SLDED from aqueous SDS/SLDED binary blend solution to the micelle, ΔγGθm, was respectively increased from -41.098 to -39.833 kJ·mol-1, -39.488 and -38.184 kJ·mol-1 while the concentrations of HP-β-CD increased from 0 to 0.400, 0.800 and 1.200 mmol·L-1. The results of Job’s plot for inclusion complexation of SLDED with HP-β-CD indicated that “HP-β-CD/SLDED” inclusion might be formed with the molar ratio of 2∶1. The concentration of SLDED in aqueous SDS/SLDED binary blend solution, could be accurately calculated by adding HP-β-CD with the molar ratio of 2∶1, and the recovery rate of SLDED was 100.8%~101.4%. The results of 1H-NMR and FT-IR exhibited that the interference of SDS on determination of SLDED could be greatly reduced because of the formation of SLDED/HP-β-CD inclusion with SLDED molecule locating within the HP-β-CD molecule.