Pharmaceutical preparation Physiological fluids

The octanol-water partition coefficient scale may not be the best tool for hydrophobicity evaluation. The ability of MLC for hydrophobicity measurement and some studies on quantitative structure retention activity relationships (QSAR) are described in Chapter 9. Chapters 10 and 11 contain selected examples of applications in the analysis of a variety of samples, especially pharmaceutical preparations and physiological fluids, some of them are taken from the authors own experience. Details on the nature of the sample, stationary phase, mobile phase composition, detection wavelength, and figures of merit, are tabulated at the end of each of these... 

In the nineties, the number of analytical procedures in MLC proposed by several authors increased, especially in the field of the determination of drugs in physiological fluids and pharmaceutical preparations. The analysis of other types of samples was less frequent. This chapter shows the experimental procedures to be followed in handling micellar mobile phases for the analysis of several types of samples, with the exception of physiological fluids, which will be considered in the next chapter, owing to the particular characteristics and interest of these samples. 

The hydrophilic vitamins are a disparate group of compounds with few conunon properties apart from water solubility. This single fact, however, makes TLC an obvious choice for their separation, particularly in pharmaceutical preparations and food products. At physiological concentrations, TLC may equally well be employed, following extraction of the vitamins fi om tissues or body fluids, but this must be under acid conditions as most of these compounds are unstable at high pH. Some are also light-sensitive. Special means of detection may also be required unless samples have been greatly concentrated, since tissue levels of most hydrophilic vitamins are low or very low. 

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