Department of Chemistry, Smith and Kolthoff Halls, University of Minnesota, 207 Pleasant Street S.E., Minneapolis, Minnesota 55455, USA.
Anal Chem. 2012 Aug 7;84(15):6747-52. doi: 10.1021/ac301248h. Epub 2012 Jul 18.
Background correction is a very important step that must be performed before peak detection or any quantification procedure. When successful, this step greatly simplifies such procedures and enhances the accuracy of quantification. In the past, much effort has been invested to correct drifting baseline in one-dimensional chromatography. In fast online comprehensive two-dimensional liquid chromatography (LC×LC) coupled with a diode array detector (DAD), the change in the refractive index (RI) of the mobile phase in very fast gradients causes extremely serious baseline disturbances. The method reported here is based on the use of various existing baseline correction methods of one-dimensional (1D) liquid chromatography to correct the two-dimensional (2D) background in LC×LC. When such methods are applied orthogonally to the second dimension ((2)D), background correction is dramatically improved. The method gives an almost zero mean background level and it provides better background correction than does simple subtraction of a blank. Indeed, the method proposed does not require running a blank sample.
背景校正(Background correction)是在进行峰检测或任何定量程序之前必须执行的非常重要的步骤。如果成功,这一步骤将极大地简化这些程序并提高定量的准确性。在过去,人们投入了大量的精力来校正一维色谱中的漂移基线。在快速在线全二维液相色谱(LC×LC)与二极管阵列检测器(DAD)耦合的情况下,非常快速梯度中流动相的折射率(RI)的变化会导致极其严重的基线干扰。这里报道的方法基于使用一维(1D)液相色谱的各种现有的基线校正方法来校正 LC×LC 中的二维(2D)背景。当这些方法正交应用于第二维(2D)时,背景校正得到了极大的改善。该方法提供了几乎为零均值的背景水平,并且比简单的空白相减提供了更好的背景校正。实际上,所提出的方法不需要运行空白样品。