Krupcík J, Spánik I, Benická E, Zabka M, Welsch T, Armstrong D W
Department of Analytical Chemistry, Faculty of Chemical Technology, Slovak Technical University, Bratislava.
J Chromatogr Sci. 2002 Oct;40(9):483-8. doi: 10.1093/chromsci/40.9.483.
The enantioselective tuning of two columns coupled in series is investigated in chiral high-resolution gas chromatography. Two columns with opposite enantioselectivities (Chirasil-L-Val and Chirasil-D-Val) are coupled in series via a T connector, and the relative retention of enantiomers chromatographed on the system is changed by varying the individual carrier gas flow rates in the coupled columns. The flow-rate ratio necessary for the required selectivity is calculated on the basis of the measured retention factors on the individual columns. The performance of this method for adjusting selectivity is studied by the separation of enantiomers of the N-TFA-O-methyl esters of six amino acids. It is demonstrated that the change of the coupling point carrier gas pressure, at the constant inlet and outlet pressures, may change the enantioselectivity of the given column series to such an extent that the enantiomer elution order may be reversed.
在手性高分辨率气相色谱中，研究了串联耦合的两根色谱柱的对映体选择性调节。两根具有相反对映体选择性的色谱柱（Chirasil-L-Val和Chirasil-D-Val）通过一个T型连接器串联耦合，通过改变耦合柱中各自的载气流速来改变在该系统上色谱分离的对映体的相对保留率。根据在各柱上测得的保留因子，计算出所需选择性所需的流速比。通过分离六种氨基酸的N-TFA-O-甲酯对映体，研究了该调节选择性方法的性能。结果表明，在恒定的入口和出口压力下，耦合点载气压力的变化可能会使给定柱系列的对映体选择性发生改变，以至于对映体的洗脱顺序可能会颠倒。
