SDS/CTAB/H2O的双水相性质及萃取作用

正负离子表面活性混合物;牛血清蛋白质;色氨酸;SDS/CTAB/H2O的双水相性质及萃取作用

Property and Extractability of Aqueous Two-phase System of SDS/CTAB/H2O

The cationic anionic surfactant mixtures are able to form an aqueous two phase system(ATPS). The pseudo ternary phase diagram of SDS/CTAB/H 2 O/Na 2 SO 4 system has been examined in the paper. The factors relating the formation time of ATPS and the distribution coefficient of bovine serum albumin(BSA) and tryptophane(Trp) in different ATPS regions have been investigated. It is shown that salt kind and its concentration and the phase volume ratio of system have important influence on the ATPS forming time. It needs at least 30 h for SDS/CTAB/H 2O system to form ATPS. However, the ATPS forming time would reduce to 1 min if there is 0 5 mol/L NaSO 4 in the system. When the ratio of top volume to bottom volume is 1, the ATPS forming time is shortest. The higher the hydrophobicity of the compound, the easier it would be extracted by the surfactant rich phase. Small water soluble compound can not be extracted in ATPS. When the electricity of compound is just opposite to that of the ordered combining structure of surfactant rich phase, the distribution coefficient would be much high.