Sentence:  In our work the best procedure for <WSD>removing</WSD> substances causing nonspecific staining in order to obtain specific conjugates was to pass the conjugates through a DEAE-cellulose column and in some cases to absorb the first and second milliliter fractions with sweet clover tissue powder . 
Meaning of the word marked with <WSD> tags:  remove something concrete, as by lifting, pushing, or taking off, or remove something abstract