反相 正相 离子交换
分析物 中-低极性 低-高极性/中性  带电荷、可电离
分离机制 基于疏水性的分离 基于极性的分离 基于电荷的分离
样品基质 水溶液 非极性有机溶剂 水溶液/低离子强度
SPE吸附剂的活化/平衡 1. 用极性有机溶剂得到的溶剂化物
2. 水
非极性有机溶剂 低离子强度缓冲液
初步冲洗步骤 水溶液/缓冲液 非极性有机溶剂 低离子强度缓冲液
洗脱步骤 增加极性有机溶剂的含量 增加混合有机溶剂的洗脱强度 更强的缓冲液——通过调节离子强度或pH值而中和电荷
吸附剂官能团 C18, tC18, C8, tC2, CN, NH2, HLB, RDX, Rxn RP  Silica, Alumina, Florisil, Diol, CN, NH2 Accell Plus QMA, NH2, SAX, MAX, WAX Accell Plus CM, SCX, MCX, WCX, Rxn CX 
吸附剂表面极性 低至中等 高至中等
典型溶剂的极性范围 高至中等 低至中等
典型的上样溶剂 水、低强度缓冲液 正己烷、氯仿、二氯甲烷 水、低强度缓冲液 水、低强度缓冲液
典型的洗脱溶剂 MeOH/水、CH3CN/水 乙酸乙酯、丙酮、CH3CN 缓冲液、高离子强度的盐类,提高pH 缓冲液、高离子强度的盐类,降低pH
样品洗脱顺序 最大极性样品组分最先洗脱出来 最弱极性样品组分最先洗脱出来 最弱电离样品组分最先洗脱出来 最弱电离样品组分最先洗脱出来
为洗脱化合物而做的流动相溶剂改变 减弱溶剂极性 增强溶剂极性 增加离子强度或提高pH值 增加离子强度或降低pH值


This has been a brief introduction to sample enrichment and purification using solid-phase extraction [SPE]. The best way to start using SPE is to first learn what others have done with analytes and/or matrices similar to those of interest to you. You will find > 7,700 references to the use of SPE in the Resource Library on waters.com. Fill in the blank with a partial compound or matrix name in the following search phrase:
“Sep-Pak” OR “Oasis” AND ______*

NOTE: Rather than risk a spelling error, use an asterisk [*] with a root name for best results. Using this same search string, even more references [> 60,000] may be found on GOOGLE Scholar.

Further reading:

J.C. Arsenault and P.D. McDonald, Beginners Guide to Liquid Chromatography, Waters [2007]; Order P/N 715001531 on waters.com

P.D. McDonald and E.S.P. Bouvier, A Sample Preparation Primer and Guide to Solid-Phase Extraction Methods Development, Waters [2001] Search for WA20300 on waters.com

Waters, Purity by SPE [2008]; Search for 720001692en on waters.com

U.D. Neue, P.D. McDonald, Topics in Solid-Phase Extraction. Part 1. Ion Suppression in LC/MS Analysis: A Review. Strategies for its elimination by well-designed, multidimensional solid-phase extraction [SPE] protocols and methods for its quantitative assessment [2005]; Search for 720001273en on waters.com

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