Pharmaceutical separations, elevated

TABLE 18-1. Pharmaceuticals Separated at Elevated Temperature Usiug Couveutioual Mobile Phases... 

In the pharmaceutical industry, it is essential to produce pure drug substance, suitable for human consumption, in a cost-effective manner. The purity of a drug substance can be checked by separation techniques such as GC, TLC, and HPLC. Both techniques tend to be more sensitive and specific than spectroscopic methods. HPLC has an advantage over GC as an analytical technique, since analytes need be neither volatile nor extremely stable to elevated temperatures. Highly accurate, almost universal detectors, such as... 

Monolithic supports are commonly used for environmental applications and will be discussed in more detail later.-5 Batch reactors are used mostly for small-scale production such as the hydrogenation of intermediates in the production of medicines in the pharmaceutical industry. The catalyst powder is mixed in a precise amount of reactant in a pressurized-stirred autoclave. A gaseous reactant, usually H2, is introduced at elevated pressures and the reaction proceeds with continuous monitoring of the H2 consumed. The catalyst is separated from the product via filtration and is often used again depending on its retained activity and selectivity. 

Like gas chromatography (GC), HPLC employs a chromatographic column for the separation. It differs from GC in that the sample components need not be volatile and stable at elevated temperatures, they must only be soluble in a suitable single-component or mixed solvent. Various modes of HPLC can be applied to the analysis of a large variety of sample types containing non-polar, moderately or strongly polar and ionic compounds, either simple species or high-molecular mass synthetic polymers or biopolymers. These features of HPLC are especially useful in pharmaceutical and clinical analysis. 

The separative process of filtration is widely used within the biopharmaceutical industry to remove contaminants from liquids, air, and gases, such as particulate matter but especially microorganisms. Microorganism removal is either required to achieve a sterile filtrate or, if the pharmaceutical product is thermally sterilized, to reduce the bioburden and, therefore, avoid elevated levels of endotoxins—the debris of gram-negative organisms. ... 

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