双水相萃取是一种新型的液-液萃取技术,具有方法简单,易操作,成本低,易放大,条件温和,可保持蛋白质活性等明显优势,特别适用于生物样品的前处理和组分分离。本文建立了15% PEG-4000/8% NaH 2 PO 4双水相体系,通过两次双水相萃取结合高效液相色谱法(HPLC)分离了唾液中的多种蛋白质。经过双水相萃取,对上、下两相中的蛋白质进行色谱的梯度洗脱分析。50 min 内蛋白质的色谱峰可分为10组,根据其在上、下两相的分配规律还可划分为6个组分区。结果表明,两次双水相萃取结合 HPLC 可以实现唾液中的蛋白质的选择性分离。该法为复杂生物样品中的蛋白质多维度、选择性分离和分析提供了新的思路。
Saliva protein separation by one-step aqueous two-phase extraction( ATPE)in the system of 15%(mass ratio if not specified)PEG-4000 / 8% NaH 2 PO 4 was presented. The proteins extracted from the top and bottom phases were separated and characterized by high performance liquid chromatography( HPLC)respec-tively. Under the optimized gradient elution procedure,more saliva protein peaks in the two phases were shown. Saliva protein peaks in 50 min gradient were divided into ten specific groups which were classified into six sections based on the protein distribution in the top and bottom phases. Then,the top or bottom phase was performed the second step ATPE. Possible reasons for protein partition and retention difference are discussed briefly. Results show that some proteins can be separated completely in one-step ATPE,while some can be sep-arated in the following two-step ATPE. The combination of two steps ATPE and HPLC provides a new way to achieve selective separation.