Chromatography processes employ doped sol gel glasses as chromatographic media. In one embodiment, a process for qualitative or quantitative determination of a reactive chemical contained in a sample comprises passing the sample through a column or planar chromatography apparatus wherein the apparatus includes packing or plates containing a porous doped sol gel glass. The doped sol gel glass is formed form a metal alkoxide and contains a compound encapsulated therein which is reactive with the reactive chemical in the pores of the doped sol gel glass. In another embodiment, a process for analyzing a gas sample containing a reactive chemical comprises passing the gas sample through glass capillaries or tubes containing porous doped sol gel glass pellets. The pellets are formed from a metal alkoxide and contain a colorimetric reagent encapsulated therein which is reactive with the reactive chemical in the pores of the pellets. In a third embodiment, a doped sol gel glass is included in the chromatographic media for pretreatment cleanup for interference removal prior to the chromatographic separation.