将PEG 400从血浆中去除的主要目的就是为了清除可能引发的离子抑制效应。图5为由下面方程式得出的基质效应数据一览，据最新AAPS论文报道6。
基质效应 =（含PEG的峰响应值/不含PEG的峰响应值）
图表A所示数据来源于经Oasis
MCX萃取去除PEG的血浆样品。图表B所示数据来源于经萃取后又加入PEG的血浆样品，可以看到在样品制备过程中未去除PEG的结果。由图显示，若未去除PEG，醋丁洛尔和美托洛尔受到严重的离子抑制作用影响，基质效应因子分别为0.45和0.77。由上述数据可以清晰看出，那些与PEG峰共流出的分析物，使用Oasis
MCX SPE板去除PEG后，离子抑制效应能得以有效清除。经PEG去除后，最终醋丁洛尔和美托洛尔的基质效应因子分别为0.93和1.04。
结论
Oasis MCX
96孔板提供了一种用于去除血浆样品中高浓度PEG的简便、快捷、高效的方法，从而消除早期药代动力学研究中常见的基质效应（通常是离子抑制效应）。此外，该解决方案无需进行色谱分析方法的再开发、样品的稀释、及其他费时费力的流程即可成功解决上述问题，这使得整个解决方案广泛适用于高通量分析的应用。
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