In chromatography, endcapping refers to the replacement of accessible silanol groups in a bonded stationary phase by trimethylsilyl groups.
Endcapping technology prevents the tailing of a polar compound's peak and shows very high durability even with an alkaline mobile phase because of the strong film covering the stationary phase surface.
The amount of available silanol groups is reduced. (...)
With an endcapping the influence of non derivatized silanol groups can be minimized. The endcapping reagent is generally a smaller silane than used for derivatisation. This treatment reduces the unwanted interaction of polar or charged analytes (acids, bases ect.) because the amount of available silanol groups is reduced.