Thus the separation of analytes is achieved.
During this procedure, it also drives the mixture priorly dropped on the lower parts of the plate with a pipette upwards with different flow rates. In this method, the mobile phase travels upward through the stationary phase The solvent travels up the thin plate soaked with the solvent by means of capillary action. in column chromatography (alumina, silica gel, cellulose) can be utilized. As adsorbent material all solid substances used. In this method stationary phase is a solid adsorbent substance coated on glass plates. Thin-layer chromatography is a “solid-liquid adsorption” chromatography. Paper chromatography is a “liquid-liquid” chromatography. In this method a thick filter paper comprised the support, and water drops settled in its pores made up the stationary “liquid phase.” Mobile phase consists of an appropriate fluid placed in a developing tank. In paper chromatography support material consists of a layer of cellulose highly saturated with water. Īffinity chromatography.Paper chromatography Besides, dextran, agorose, polyacrylamide are also used as column materials. Sephadeks G type is the most frequently used column material. Molecules smaller than the pores are diffused into pores, and as molecules get smaller, they leave the column with proportionally longer retention times ( Figure 3).
Larger molecules pass through spaces between porous particles, and move rapidly through inside the column. Molecules larger than pores can not permeate into gel particles, and they are retained between particles within a restricted area. The solution containing molecules of different dimensions are passed continuously with a constant flow rate through the column. In a gel- permeation column stationary phase consists of inert molecules with small pores.
This procedure is basically used to determine molecular weights of proteins, and to decrease salt concentrations of protein solutions. The basic principle of this method is to use dextran containing materials to separate macromolecules based on their differences in molecular sizes. Ion- exchange chromatography.Gel- permeation (molecular sieve) chromatography Some of them include column chromatography, thin-layer chromatography (TLC), paper chromatography, gas chromatography, ion exchange chromatography, gel permeation chromatography, high-pressure liquid chromatography, and affinity chromatography. Various chromatography methods have been developed to that end. The purpose of applying chromatography which is used as a method of quantitative analysis apart from its separation, is to achive a satisfactory separation within a suitable timeinterval. Liquid chromatography is used especially for thermal unstable, and non-volatile samples. Gas chromatography is applied for gases, and mixtures of volatile liquids, and solid material. If mobile phase is liquid it is termed as liquid chromatography (LC), and if it is gas then it is called gas chromatography (GC). Mobile phase flowing over the stationary phase is a gaseous or liquid phase. Stationary phase in chromatography, is a solid phase or a liquid phase coated on the surface of a solid phase. Agarose-gel chromatography is used for the purification of RNA, DNA particles, and viruses. Paper chromatography is used in the separation of proteins, and in studies related to protein synthesis gas-liquid chromatography is utilized in the separation of alcohol, esther, lipid, and amino groups, and observation of enzymatic interactions, while molecular-sieve chromatography is employed especially for the determination of molecular weights of proteins. ion-exchange chromatography) are more effective in the separation of macromolecules as nucleic acids, and proteins. Chromatography methods based on partition are very effective on separation, and identification of small molecules as amino acids, carbohydrates, and fatty acids. The type of interaction between stationary phase, mobile phase, and substances contained in the mixture is the basic component effective on separation of molecules from each other.
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