Octadecyl dihydrogen phosphate

Sheng Y, Zhou B, Zhao J, Tao N, Yu K, Tian Y, Wang Z (2004) Influence of octadecyl dihydrogen phosphate on the formation of active super-fine calcium carbonate. J Colloid Interface Sci 272((2) 326-329... 

Table 2.1 HPLC capacity factors for secbuto-barbitone and vinbarbitone with an octadecyl silyl stationary phase and mobile phases of methanoiyO.l M sodium dihydrogen phosphate (40 60) at (a) pH 3.5, and (b) pH 8.5. From Moffat, A.C. (Ed.), Clarke s Isolation and Identification of Drugs, 2nd Edn, The Pharmaceutical Press, London, 1986. Reproduced by permission of The Royal Pharmaceutical Society...

Reversed-phase HPLC was used by Jatlow et al. for the analysis of cocaine and its metabolites 1n urine (Fig.4.7). An amount of 0.1 ug/ml cocaine could be detected by using a microparticulate octadecyl column and an acidic mobile phase consisting of 0.25 M potassium dihydrogen phosphate (pH 2.7) containing 17 acetonitrile. For the analysis of cocaine in plasma, an... 

To separate theophylline from 1,7-dimethylxanthine, Rodriguez et al.177 used methanol -formamide - potassium dihydrogen phosphate (0.05 M)(22 11.5 66.6)(pH 5.8) in combination with an octadecyl type of column. 

Figure 10.8 Separation of hydrophilic compounds on three different octadecyl columns [redrawn with permission from M.R. Euerby and P. Petersson, J. Chromatogr. A, 994, 13 (2003)]. Stationary phases Prontosil C18 AQ (similar, Fs = 7.7), Genesis AQ (reference) and Platinum EPS C18 (different, Ag —58). Conditions columns, 15cm x 4.6mm i.d. mobile phase, 1 mlmin potassium dihydrogen phosphate pH 2.7 in water-methanol (96.7 3.3) temperature, 6O C UV detector, 210nm. Peaks 1—nicotine 2 = benzylamine 3 = procainamide 4 = terbutaline 5 —salbutamol 6 —phenol. 

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