الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
1.1. History of HPLC:
Chromatography was first developed by the Russian botanist ”Mikhail Tswett” in 1903 as he produced a colorful separation of plant pigments through a column of calcium carbonate. Since then, chromatography was developed into a valuable tool in separation and identification of compounds. High performance liquid chromatography (HPLC) is a high-resolution separation tool that has revolutionized large number of areas of science and technology. The basic theory behind high performance liquid chromatography is not new, but it was not developed until around 1969. This development introduced the effective use of a small diameter packing material and columns, which allowed the chromatographer to perform separations faster and with greater resolution than had previously been attainable. The basic of separation in HPLC involves partitioning of the analyte molecule between a liquid mobile phase and a solid stationary phase [285].
1.2. What is HPLC?
High-performance liquid chromatography (sometimes referred to as high-pressure liquid chromatography), HPLC, is a chromatographic technique used to separate a mixture of compounds in analytical chemistry and biochemistry with the purpose of identifying, quantifying and purifying the individual components of the mixture. HPLC has many uses including medical (e.g. detecting vitamin D concentrations in blood serum), legal (e.g. detecting performance enhancement drugs in urine), research (e.g. purifying substances from a complex biological sample, or separating similar synthetic chemicals from each other), determination of drugs in biological fluids and in pharmaceutical formulations, stability indicating methods for determination of drugs in the prescence of its degradation products, and manufacturing (e.g. pharmaceutical quality assurance).
HPLC relies on the pressure of mechanical pumps on a liquid solvent to load a sample mixture onto a separation column, in which the separation occurs. An
HPLC separation column is filled with solid particles (e.g. silica, polymers, or sorbents), and the sample mixture is separated into compounds as it interacts with the column particles. HPLC separation is influenced by the liquid solvent’s condition (e.g. pressure, temperature, etc….), chemical interactions between the sample mixture and the liquid solvent (e.g. hydrophobicity, protonation, etc…), and chemical interactions between the sample mixture and the solid particles packed inside of the separation column (e.g. ligand affinity, ion exchange, etc...).
The schematic of an HPLC instrument typically includes a sampler by which the sample mixture is injected into the HPLC, one or more mechanical pumps for pushing liquid through a tubing system, a separation column, a digital analyte detector (e.g. a UV/Vis, or a photodiode array (PDA)) for qualitative or quantitative analysis of the separation, and a digital microprocessor for controlling the HPLC components (and user software) [286]. A diagram showing the main parts is simplified in Figure 1.