The prediction of RF values

✍ Scribed by R.P. Ouelette; J.F. Balcius

• Book ID: 104144206
• Publisher: Elsevier Science
• Year: 1967
• Tongue: English
• Weight: 506 KB
• Volume: 29
• Category: Article
• ISSN: 1873-3778
• DOI: 10.1016/s0021-9673(00)92656-6

✦ Synopsis

XOTES

247

fraction was allowed to evaporate at room temperature and the residue was dissolved in 2 ml of ethanol for measurement of ultraviolet absorption. For estimation of these steroids with Porter-Silber reagent, the residue was dissolved in 0.5 ml of 60 O/~ aqueous ethanol and then 1.0 ml of Porter-Silber reagent was added and mixed. The mixture was allowed to stand at room temperature for 15 h and the optical density , was measured at 410 rnp. The recovery of steroids was 75 to 80 %. The elution pattern is shown in Fig. I. The column could be used repeatedly.

Since the solutes distributed themselves between the less polar outer liquid phase and the more polar swollen stationary phase which is in equilibrium with the liquid phase, the elution sequence of I7-hydroxycorticosterolcls resembled that in straight phase partition chromatography.

This type of partition chromatography, which utilizes synthetic cross-linked polymer of medium polarity as the stationary phase and a less polar solvent mixture consisting of smaller amounts of polar components (e.g., ethanol and water) and larger amounts of less polar components (e.g., benzene and qz-hexane) as the moving phase, seems to be useful for the separation of neutral organic compounds of moderate and higher polarity.