Programmable selectivity for GC with series-coupled columns using pulsed heating of the second column.
Programmable selectivity for GC with series-coupled columns using pulsed heating of the second column.
复制标题
使用第二根色谱柱的脉冲加热，通过串联色谱柱实现 GC 的可编程选择性。
DOI：
10.1021/ac020614h
复制
发表时间：
2003
影响因子：
7.4
通讯作者：
Sacks,Richard
中科院分区：
文献类型：
--
作者：
Whiting,Joshua;Sacks,Richard
一个串联耦合的合奏的非极性二甲基聚硅氧烷柱和极性三氟丙基甲基聚硅氧烷柱与独立的在柱加热被用来获得第二柱的脉冲加热。对于由第一柱分离但与柱系综共混的混合物组分带，在两种组分中的第一种组分已经穿过柱接合点并且在第二柱中之后开始温度脉冲，而另一种组分仍然在第一柱中。这将加速第一个分量的频带。如果第二柱在第二组分谱带穿过结之前充分冷却，则第二谱带经历较少的加速，并且对于总体色谱图中的相应峰观察到增加的分离。通过用电阻加热丝和传感器丝包裹熔融石英毛细管柱来获得高速柱旁加热。通过1000 °C/min的短持续时间线性加热斜坡实现温度脉冲的快速加热。在脉冲期间，第二柱温度在几秒钟内增加20−100 °C。使用冷气体环境，可以在25秒内冷却到30 °C的静态温度。描述了温度脉冲起始时间和幅度对系综峰分离和分辨率的影响。使用一系列适当定时的温度脉冲来分离13组分混合物中的三个共洗脱组分对。
A series-coupled ensemble of a nonpolar dimethyl polysiloxane column and a polar trifluoropropylmethyl polysiloxane column with independent at-column heating is used to obtain pulsed heating of the second column. For mixture component bands that are separated by the first column but coelute from the column ensemble, a temperature pulse is initiated after the first of the two components has crossed the column junction point and is in the second column, while the other component is still in the first column. This accelerates the band for the first component. If the second column cools sufficiently prior to the second component band crossing the junction, the second band experiences less acceleration, and increased separation is observed for the corresponding peaks in the ensemble chromatogram. High-speed at-column heating is obtained by wrapping the fused-silica capillary column with resistance heater wire and sensor wire. Rapid heating for a temperature pulse is obtained with a short-duration linear heating ramp of 1000 °C/min. During a pulse, the second-column temperature increases by 20−100 °C in a few seconds. Using a cold gas environment, cooling to a quiescent temperature of 30 °C can be obtained in ∼25 s. The effects of temperature pulse initiation time and amplitude on ensemble peak separation and resolution are described. A series of appropriately timed temperature pulses is used to separate three coeluting pairs of components in a 13-component mixture.