新型亲和双水相成相剂Triton X-100-IDA-Cu(Ⅱ)的制备

以小分子表面活性剂Triton X-100为载体,采用环氧氯丙烷(ECH)活化法偶联亚氨基二乙酸(IDA),通过配位反应螯合Cu(Ⅱ),合成了一种新型亲和双水相成相剂Triton X-100-IDA-Cu(Ⅱ),并对其合成条件进行了优化.结果表明:最佳活化工艺为n(ECH)∶n(Triton X-100)=2∶1,n(BF_3)∶n(Triton X-100)=1∶25,冰浴反应22 h,按n(NaOH)∶n(Triton X-100)=1∶1加入Na OH,环氧化反应3 h,环氧产物得率达到72.4%;最佳偶联工艺为pH 13条件下,加入等摩尔的IDA,55℃反应21 h,IDA的偶联率为76.3%;最佳螯合工艺为在0.05 mol/L醋酸钠溶液中,n(CuSO+4)∶n(Triton X-100-IDA)=1∶1,室温反应6 h,Cu(Ⅱ)的螯合率可达80.5%.通过测定Triton X-100-IDA-Cu(Ⅱ)与阳离子型疏水改性聚氧乙烯(HM-EO)所构成的双水相系统的相图,知两者可形成带亲和配基的稳定双水相系统.

Preparation of Iminodiacetic Acid-Polyethylene Glycol for Immobilized Metal Ion Affinity Partitioning

The synthesis route was investigated and optimized for the preparation of iminodiacetic acid-polyethylene glycol (IDA-PEG) for immobilized metal ion affinity partitioning in aqueous two-phase systems. IDA-PEG was synthesized from PEG in two steps by the reaction of iminodiacetic acid with a monosubstituted derivative of epichlorohydrin-activated PEG. The Cu2+ content combined with IDA-PEG was determined by atomic absorption spectrometry as 0.5 mol·mol^-1 (PEG). Furthermore, the affinity partitioning behavior of lactate dehydrogenase in polyethylene glycol/hydroxypropyl starch aqueous two-phase systems was studied to clarify the affinity effect of the Cu(Ⅱ)-IDA-PEG.