Drug product phase pure

The ideal solubility equation has significant value in chiral systems, where a single enantiomer is desired as the product [20]. The behaviour of chiral compounds is very important in biological systems and in drug development, where it is typical for just one enantiomer of an API to be biologically active. The undesired enantiomer may be inert, or possess more serious toxicity effects, as in the case of Thalidomide. Many enantiomeric systems form three discrete solid phases, depending on the solution concentration. Pure crystals of each enantiomer will form at high concentrations of their respective enantiomer. At... 

Emulsions are either oil phase dispersed in water phase, an oil-in-water (o/w) emulsion, or water phase dispersed in oil phase, a water-in-oil (w/o) emulsion. If a poorly water-soluble drug substance is soluble in oil, it can be solubilized in an emulsion where it partitions into the oil phase. The total solubility in an emulsions, is the summation of concentrations in the aqueous and oil phases (Strickley, 2004). The total solubility of the emulsion system is the sum of the drug concentration in the aqueous phaseSv, and the concentration in the oil phase, which can be approximated by the product of the drug s solubility in the pure oi i, multiplied by the fraction of the oil in the emulsion ... 

El-Sherif et al. [79] developed and validated a reversed-phase HPLC method for the quantitative determination of omeprazole and two other proton pump inhibitors in the presence of their acid-induced degradation products. The drugs were monitored at 280 nm using Nova-Pak Ci8 column and mobile phase consisting of 0.05 M potassium dihydrogen phosphate-methanol-acetonitrile (5 3 2). Linearity range for omeprazole was 2-36 fig/ml. The recovery of omeprazole was 100.50 0.8%, and the minimum detection was 0.54 /zg/ml. The method was applied to the determination of pure, laboratory prepared mixtures, and pharmaceutical dosage forms. The results were compared with the official USP method for omeprazole. 

Sadtler Collection. The most comprehensive collection of published spectra is that of the SadU Researdi Laboratories. Li the solid liquid phases, over 63 000 spectra of pure compounds including 600 spectra of commonly abused ugs, 600 spectra of pieptoxic chemicals have been published, in addition to 36 000 spectra of commercud products. There are also 7400 spectra in the vapom phase. Mpropriate Fourier transform spectrophotometer. 

Fluorous chemistry integrates the characteristics of solution-phase reactions and the phase tag strategy developed for solid-phase chemistry [7-15], Perfluoroalkyl chains instead of polymer beads are used as the phase tags to facilitate the separation process. In 2001 the Curran group first reported the concept of fluorous mixture synthesis (FMS) for solution-phase library synthesis [16], FMS is able to produce individual pure compounds without the effort of deconvolution. It adapts literature procedures to synthesize complex natural products, their enantiomers and diastereomers. FMS can also be used for the development of new synthetic protocols and to make novel drug-like molecules [17, 18],... 

Similarly, if the racemic mixture is composed of basic drugs, use is made of camphor-10-sulfonic acid, a natural product obtainable as an optically pure enantiomer. An example of the type of reactions involved is shown in Figure 4.13, where a pair of enantiomeric alcohols is resolved by reaction with phthalic anhydride and an optically pure base to form a pair of diastereoisomeric salts. Reactions of this type can be tedious to perform and, with the advent of HPLC with chiral stationary phases, are gradually being replaced. 

Some examples of preparative enantioseparation of chiral drugs are summarized in Table 9. Overall, SMB chromatography is a powerful tool for the production of enantiomerically pure compounds on a large scale within a short phase of development. The availability of software which allows scaling-up of an analytical enantioseparation to SMB technology is a crucial advantage. The characteristics of SMB chromatography are such as to provide pure... 

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