HP-β-CD降低脂肪醇聚氧乙烯醚对十二烷基二苯醚二磺酸钠紫外光谱的影响

Reducing the effect of AEO-7 on UV spectrum of SLDED with HP-β-CD

在SLDED(十二烷基二苯醚二磺酸钠)与AEO-7(脂肪醇聚氧乙烯醚)的复合水溶液中,AEO-7可对紫外光谱法检测SLDED产生明显干扰。实验结果表明:当复合水溶液中AEO-7的浓度为1.000 mmol/L时,0.200 mmol/L SLDED的吸光度由1.527降为1.409。同时,AEO-7还会降低SLDED的表观临界胶束浓度(c_(cmc)),当AEO-7的浓度分别为0.400、1.000 mmol/L时,SLDED的c_(cmc)由纯水中的0.320 mmol/L分别降低至0.317、0.289 mmol/L。研究结果进一步表明,HP-β-CD(羟丙基-β-环糊精)能有效消除AEO-7对SLDED检测结果的干扰作用,在复配体系中按n(SLDED)∶n(HP-β-CD)=1∶2加入HP-β-CD后,复配体系中SLDED的检测准确度明显提高。综合红外光谱表征与核磁共振氢谱表征的结果,可推测出SLDED分子进入HP-β-CD分子空腔,并形成n(SLDED)∶n(HP-β-CD)为1∶2的包结物,是HP-β-CD消除AEO-7对SLDED的干扰以及阻断SLDED分子形成胶束的主要原因。

In the complex aqueous solution of SLDED(sodium dodecyl diphenyl ether disulfonate)and AEO-7(fatty alcohol polyoxyethylene ether),AEO-7 can significantly interfere with the detection of SLDED by UV spectrometry.The experimental results indicate that the absorbance of 0.200 mmol/L SLDED decreases from 1.527 to 1.409 when the concentration of AEO-7 in the complex aqueous solution is 1.000 mmol/L.Meanwhile,AEO-7 also decreases the apparent critical micelle concentration(c_(cmc))of SLDED.When the concentrations of AEO-7 is 0.400 mmol/L and 1.000 mmol/L,c_(cmc)of SLDED in the pure water decreases from 0.320 mmol/L to 0.317 mmol/L and 0.289 mmol/L,respectivly.The results further show that HP-β-CD(hydroxypropyl-β-cyclodextrin)can effectively eliminate the interference effect of AEO-7 on SLDED assay results,and the accuracy of SLDED assay in the compound system is significantly improved after the addition of HP-β-CD in the compound system at a molar ratio of 12.Combining the results of infrared spectroscopic characterization and nuclear magnetic resonance hydrogen spectroscopy,it can be speculated that the entry of SLDED molecules into the molecular cavity of HP-β-CD and the formation of an inclusion junction with a molur ratio of 1∶2 are the main reasons for HP-β-CD to eliminate the interference of AEO-7 on SLDED and to block the formation of micelles by SLDED molecules.