High-pressure liquid chromatography principles

This chapter presents an overview of current trends in high-pressure liquid chromatography (HPLC) instrumentation focusing on recent advances and features relevant to pharmaceutical analysis. Operating principles of HPLC modules (pump, detectors, autosampler) are discussed with future trends. 

DeCleyn and Verzele (3Q.3J-.32) isolated the four possible isomers from piperinic acid irradiated in an ultra-violet reactor, by counter-current distribution and also the piperidides obtained synthetically from the treated piperinic acid by high pressure liquid chromatography (figure 4). The structures of the isomers were derived mainly from NMR data. Their pungency was recorded, but possibly not by rigorous methods (31.32). The results confirmed the observation of Grewe t ail. (29) that piperine is the pungent principle of pepper, and that other isomers have little taste. ... 

High-performance liquid chromatography (or less common, high-pressure liquid chromatography, HPLC) is a preferred method of analysis for many compounds because it does not require the high temperatures used in gas chromatography. Separations in HPLC can be based on either a size exclusion or on an adsorption principle. The size exclusion mode is useful for separating fatty acids from... 

La Rotonda, M.I. Cozzolino, S. Schettino, O. [Analysis of active principles in pharmaceutical doseige forms by high pressure liquid chromatography—cimetidine and zolimidine]. Boll.Soc.Ital.Biol.Sper., 1980, 56, 1394-1398... 

Kasai, H., Nishimura, S., Nagao, M., Takahashi,Y, and Sugimura, T. 1979. Fractionation of a mutagenic principle from broiled hsh by high-pressure liquid chromatography. Cancer Lett. 7 343-348. 

Supercritical fluid chromatography (SFC) is very similar in principle to, and is as convenient as, high-performance liquid chromatography, but it uses as the high-pressure eluant fluid CO2 (or other fluid) above its critical point (for CO2 Tc = 31.3°C, Pq = 7.38 MPa, pc = 0.448 g cm-3). SPC can separate relatively small and/or thermally labile molecules. The analyte is introduced as a solution in methanol. Small amounts of organic solvents can be added as "modifiers." Any C02 brought out with the analyte to ambient atmosphere will evaporate harmlessly. 

---