𝔖 Bobbio Scriptorium
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A warning against the use of diluted stock solutions of apolar silicones for coating glass capillary columns

✍ Scribed by Grob, K. ;Grob, G.


Publisher
John Wiley and Sons
Year
1978
Tongue
English
Weight
174 KB
Volume
1
Category
Article
ISSN
0935-6304

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✦ Synopsis


For the preparation of capillary columns by the static coating method [I] considerable volumes of solution containing the liquid phase in a concentration range of 0.05-2.0% are used. For convenience and economy we have for many years prepared such solutions in batches of 50-100 ml, and have continued using them over a period of several weeks or months. All solutions were stored in Sovirel bottles with Teflon-lined screw caps and kept in the dark at room temperature. No measurable loss of volatile solvent occurred even in the course of half a year.

From time to time we had periods during which wewere unable to reproduce well-elaborated column making procedures. Despite extremely exact work the new columns were unsatisfactory because of excessive activity. By chance we observed that a fresh coating solution produced again the expected column characteristics. Although we had similar experiences three times within two years, we had no proof for the correlation, since in all cases several parameters beside the coating solution had been varied. Following a preliminary warning in a recent report [2], we ran a series of column preparations in which the age of the coating solution was the only varied parameter.