1) Dissolving agent 2) Washing solution 
<chemistry> The term for the fluid (such as a buffer solution) that is used in column chromatography to separate the components of a mixed sample.The fluid is run through the column and brings out the separated substances (separately). ... (09 Oct 1997) ... 
Type: Term Pronunciation: el′yū-ant Definitions: 1. A material that has undergone elution.
a liquid used for elution.