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Introduction
Author(s) -
Leclercq Ludovic,
Lam William H.K.,
Peeta Srinivas
Publication year - 2011
Publication title -
computer‐aided civil and infrastructure engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.773
H-Index - 82
eISSN - 1467-8667
pISSN - 1093-9687
DOI - 10.1111/j.1467-8667.2010.00694.x
Subject(s) - citation , library science , history , computer science
Modern pharmaceutical formulations are complex mixtures including, in addition to one or more medicinally active ingredients, a number of inert materials such as diluents, disintegrates, colors and flavours. To ensure quality and stability of the final product, the pharmaceutical analyst must be able to separate these mixtures into individual components prior to quantitative analysis. Moreover, comparison of the relative efficacy of different dosage forms of the same drug entity requires the analysis of the active ingredient in biological matrices such as blood, urine and tissue. Among the most powerful techniques available to the analyst for the resolution of these mixtures are a group of highly efficient methods collectively called chromatography (color-writing). Because this technique is involved so intimately in all aspects of pharmaceutical research and development, the pharmacist should possess a working knowledge of chromatographic principles and techniques. Chromatographic separation relies on relative movement of two phases, similar to fractional distillation or counter current distribution. But in chromatography one phase is fixed (stationary phase) and other is mobile (mobile phase). The mobile phase passes over the stationary phase and transports components of the mixture at different speeds in the direction of the flow of mobile phase. The separation of components is a result of differential affinity of components for the mobile phase and a stationary phase. Definition: Tswett (1906) defined Chromatography as the method in which the components of a mixture are separated on an adsorbent column in a flowing system. Recently, the IUPAC has defined chromatography as: “A method used primarily for the separation of the components of a sample, in which the components are distributed between two phases, one of which is stationary while other moves. The stationary phase may be a solid or a liquid supported on a solid or a gel, and may be packed in a column, spread as a layer or distributed as a film. The mobile phase may be gaseous or liquid”.