Basicity, silanol group water exchange

Some columns require special care. Amino columns, for example, should not be exposed to solvents that contain aldehyde or keto groups. Amino columns also are only partially stable in an aqueous environment. When exposed to water, the high concentration of bond phase in the pores creates a strongly basic environment. Under these circumstances, the silica surface dissolves slowly, creating acid silanols. At some point, the acidic silanols neutralize the local basic environment, and the dissolution of the phase is slowed down or even halted. Since amino columns are often used in an aqueous environment as ion exchangers or for the analysis of carbohydrates, you should be aware of this effect. 

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