PREPARATION OF REVERSED PHASE OPEN TUBULAR LIQUID-CHROMATOGRAPHIC COLUMNS FROM BOROSILICATE GLASS

The preparation of open tubular liquid chromatographic columns with small inner diameters (less-than-or-equal-to 20-mu-m) from Pyrex 7740 borosilicate glass is described. The surface area of the inner wall of the capillary is increased by etching with a series of acidic and basic solutions. Dimethyloctadecylchlorosilane is then reacted with the column wall to create a bonded stationary phase layer. The resulting columns exhibit good retention and high efficiency. The effects of each step in the etching process are examined and the silanization reaction is optimized.