Phenyl bonded phase

Hi) How would the retention of the solutes be affected by using a phenyl bonded phase instead of the C-18 ... 

The most satisfactory HPLC conditions for analysis of VI was ultimately achieved using a phenyl-bonded phase column in the reverse phase mode. Based upon the experience described above for polymeric octadecylsi-lane, water acetonitrile was exclusively used as mobile phase in the development work. 

Figure 6. HPLC analysis of human plasma from a non-marijuana smoker to which 100 ng/mL of VI has been added. A gradient (superimposed with dashed line) beginning with 60 40, water-.acetonitrile was used on a phenyl-bonded phase...

The C)8, C8, and phenyl bonded phases are most often used in the reverse... 

Other silica-based phases that are available include phenyl and fluorinated alkyl and phenyl-bonded phases. The phenyl and fluorinated phases offer the potential for n-n interactions and show different selectivity in comparison to... 

Early PG analysis using HPLC techniques was carried out as adsorption chromatography on normal-phase (NP) columns packed with silica or alumina. The nonpolar mobile phase comprizing of organic solvents (hexane, toluene, ethyl acetate, and HOAc) allows separation of PGs which are unstable in aqueous media (e.g., PGH2 on cyano- or phenyl-bonded phases). Usually, the injection medium must be fairly polar to dissolve the PGs. This is achieved by the addition of... 

As noticed by other authors, Pettitt and Damon117 found that a phenyl-bonded phase gave better peak shapes for the alkaloids than an octyl or octadecyl type of stationary phase. However the addition of N,N-dimethyloctylamine to the mobile phase was found to be essential in order to greatly reduce tailing of opium alkaloids (Fig. 7.9). 

RSP,methylreserpate Post-column reactor for Phenyl bonded phase not ACN-0.005M NaH.PO. buffer(pH 6) ... 

Figure 3.8. Comparative chromatograms illustrating the effect of selectivity of C8, cyano-, and phenyl-bonded phases. Diagram courtesy of MAC-MOD Analytical.

Explore selectivity differences between C18, C8, polar-embedded, cyano-or phenyl-bonded phases. 

Hi) The phenyl bonded phase is slightly more polar than the C-18, and this will cause the solutes to elute faster, though it may not affect all the solutes to the same extent. 

Euerby, M.R., et al., Solvent and stationary phase selectivity in capillary electrochromatography method development Comparison of Cl8, C8, and phenyl-bonded phases for the separation of a series of substituted barbiturates, J. Microcol. Sep., 11, 305, 1999. 

HPLC has also used to determine taxol and related compounds in biological fluids [13]. After evaluating C8-, cyanopropyl-, and phenyl-bonded phases, Riley and his co-workers selected a C8-bonded phase column with a mobile phase of MeOH NaOAc buffer (0.02 M, pH 4.5, 35 65 v/v) as their system for analysis of taxol in human plasma and urine. 

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