Abstract
The bleeding of apolar high temperature columns may well be the critical factor limiting their applicability for GC/MS‐coupling, and for high temperature analyses. Therefore, a bleeding determination procedure has been designed as a basis for a systematic approach to the production of low‐bleed columns. Re‐silylation is a traditional method of reducing column bleeding. Increased efficiency of re‐silylation becomes feasible with immoblized coatings. Experience gained so far shows that resilylation of immoblized coatings may indeed result in the expected strongly reduced bleed rates and in improved overall column quality. Re‐silylation may also contribute to column washing by enhancing the solubility of adsorbed contaminants.