Lee Kyung-Ah, Yeo Sujeong, Kim Kyeong Ho, Lee Wonjae, Kang Jong Seong
College of Pharmacy, Chungnam National University, Daejeon 305-764, Republic of Korea.
J Pharm Biomed Anal. 2008 Apr 14;46(5):914-9. doi: 10.1016/j.jpba.2008.01.012. Epub 2008 Jan 17.
The enantioseparation of N-protected fluorenylmethoxycarbonyl (N-FMOC) alpha-amino acids was carried out on three polysaccharide-derived chiral stationary phases, such as cellulose tris(3,5-dimethylphenylcarbamate) (Chiralcel OD), amylose tris(3,5-dimethyl-phenylcarbamate) (Chiralpak AD) and cellulose tris(4-methylbenzoate) (Chiralcel OJ), and the influence of acetonitrile composition and pH of the eluents on the enantioseparation in reverse mode chromatography was examined. The best separation of the enantiomers was achieved with 40% acetonitrile in 50mM phosphate buffer at pH 2. However, increasing the composition of acetonitrile to 50% on Chiralcel OD yielded a considerable decrease of retention time with minimum loss of resolution. The elution order of N-FMOC alpha-amino acid enantiomers on Chiralcel OD and OJ were quite different, indicating that both phases could be used in a complementary manner for the separation of the enantiomers of N-FMOC alpha-amino acids. The positive relationship between the capacity factor of N-FMOC alpha-amino acids and the hydrophobicity of amino acids indicated that hydrophobicity plays an important role on the retention of the N-FMOC alpha-amino acids in the reverse mode.
在三种多糖衍生的手性固定相上进行了N-保护的芴甲氧羰基（N-FMOC）α-氨基酸的对映体分离，这三种固定相分别为三（3,5-二甲基苯基氨基甲酸酯）纤维素（Chiralcel OD）、三（3,5-二甲基苯基氨基甲酸酯）直链淀粉（Chiralpak AD）和三（4-甲基苯甲酸酯）纤维素（Chiralcel OJ），并研究了乙腈组成和洗脱液pH值对反相色谱中对映体分离的影响。在pH为2的50mM磷酸盐缓冲液中，含40%乙腈时对映体实现了最佳分离。然而，在Chiralcel OD上，将乙腈组成增加到50%会使保留时间显著缩短，而分离度损失最小。N-FMOC α-氨基酸对映体在Chiralcel OD和OJ上的洗脱顺序差异很大，这表明这两种固定相可互补用于分离N-FMOC α-氨基酸的对映体。N-FMOC α-氨基酸的容量因子与氨基酸疏水性之间的正相关关系表明，疏水性在反相中对N-FMOC α-氨基酸的保留起着重要作用。
