Capillary Liquid Chromatography- Mass Spectrometry
What is Chromatography?
Chromatography is the technical term for a set of laboratory approaches for the separation of mixtures (Solid/Liquid/Gas). The mixture is dissolved in a fluid which called the mobile phase, which carries it through a structure holding another material known as the stationary phase. The various constituents of the mixture transport at different velocities, causing them to separate. The separation is mainly based on differential partitioning between the mobile and it’s stationary phases. Subtle differences in a compound's partition coefficient result in differential retention time on the stationary phase and thus changing the separation (Tomer, et al., 1994).
Chromatography can be preparative or analytical. The basic purpose of preparative chromatography is to separate the components of a mixture for more advanced uses (and also it is a method of purification). Analytical chromatography is done normally with smaller amounts of material and is for measuring the relative proportions of analytic in a mixture. The two are not mutually exclusive (Covey, et al., 1986). Basically chromatography methods can categorize based on several factors.
• by chromatographic bed shape
1. Column chromatography
2. Planner chromatography (Paper and Thin layer methods)
• Displacement Chromatography
• by physical state of mobile phase
1. Gas
2. Liquid
• by separation mechanism
1. Adsorption chromatography
2. Ion exchange chromatography
3. Size exclusion chromatography
4. Partition chromatography
5. Affinity chromatography
Figure 1: Classification of Chromatography techniques.
Liquid Chromatography
Liquid chromatography (LC) is an analytical c...
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... their mass / charge ratio (m/z). Several different techniques are available for both ionization and ion analysis, resulting in many different catogories of mass spectrometers with different combinations of these two processes. In practice, some combinations are far more versatile than others and the following descriptions focus on the major types of ion sources and mass analyzers that used in LC-MS systems.
• Ion Sources
1) Electrospray Ionization Source
2) Atmospheric Pressure Chemical Ionization Source
3) Atmospheric Pressure Photo Ionization
• Mass Analyzers
1) Quadruple Analyzers
2) Time-of-flight Analyzers
3) Ion Trap Analyzers
4) Hybrid Analyzers
Applications of Capillary liquid chromatography- mass spectrometry
Biochemical screening or genetic disorders,
Drug Monitoring and Toxicology,
Vitamins and Related Metabolites,
Analysis of Steroid Hormones
The objective of this experiment was to perform extraction. This is a separation and purification technique, based on different solubility of compounds in immiscible solvent mixtures. Extraction is conducted by shaking the solution with the solvent, until two layers are formed. One layer can then be separated from the other. If the separation does not happen in one try, multiple attempts may be needed.
Cu (aq) + 2NO3 (aq) + 2Na+ (aq) + 2OH- (aq) → Cu(OH)2 (s) + 2Na+ (aq) + 2NO3(aq)
A convenient method of separating a mixture of organic compounds is recognized as liquid-liquid extraction, which involves the dispersion of a substance between two immiscible solvents using preferential solubility. Strategically using the differences in solubility of the interested solute, the compound can be transferred from one liquid part to the other during extraction. Organic acids and bases can be separated from each other by using an organic solvent like diethyl ether and a polar solvent such as water. Diethyl ether is an appropriate solvent since it wil...
Physical separation methods refer to any means of olefin/paraffin separation that use the physical properties between the species in order to achieve separation. These properties include size, shape, boiling point, vapour pressure, volatility etc.
...the mass spectrometer. This is called an electron impact source. Gases and volatile liquid samples are allowed to leak into the ion source from a reservoir. Non-volatile solids and liquids may be introduced directly. Cations formed by the electron bombardment (red dots) are pushed away by a charged repeller plate (anions are attracted to it), and accelerated toward other electrodes, having slits through which the ions pass as a beam. Some of these ions fragment into smaller cations and neutral fragments. A perpendicular magnetic field deflects the ion beam in an arc whose radius is inversely proportional to the mass of each ion. Lighter ions are deflected more than heavier ions. By varying the strength of the magnetic field, ions of different mass can be focused progressively on a detector fixed at the end of a curved tube. Because the mass of each individual ion
The distance of the initial extract line to a pigment band was divided by the distance of the marked solvent front to the initial extract line both were measured in cm. The RF (relative to front) was calculated for each pigment band, indicating the travelled distance between the pigment and the front (solvent line) on the chromatography
AMS determines the isotopic composition of a sample material by first producing a negatively-charged ion beam, which is then subjected to a series of extremely selective filtering procedures in order to find C-14.
Chromatographic process occurs due to differences in the distribution constants of individual sample components. It is the science which studies the separation of a mixture of molecules based on differences in their structure or composition.
For this experiment we have to use physical methods to separate the reaction mixture from the liquid. The physical methods that were used are filtration and evaporation. Filtration is the separation of a solid from a liquid by passing the liquid through a porous material, such as filter paper. Evaporation is when you place the residue and the damp filter paper into a drying oven to draw moisture from it by heating it and leaving only the dry solid portion behind (Lab Guide pg. 33.).
Once the mixture had been completely dissolved, the solution was transferred to a separatory funnel. The solution was then extracted twice using 5.0 mL of 1 M
As explained by Saferstein “Chromatography is a means of separating and tentatively identifying the components of a mixtur... ... middle of paper ... ... ively place the suspect or perpetrator behind bars. Analyzing soil compounds can be measured by the levels of organic molecules including n-alkanes, fatty alcohols and fatty acids, which are all found in the waxy outer layer of plant matter (Geddes, 2008). It basically states that compounds can remain in the soil for thousands of years, which explains that each area being tested has its unique organic profile.
Extraction separates compounds based on their solubility. A separatory funnel allows two distinct layers (aqueous and organic) to form when two immiscible liquids are separated with the more dense liquid on bottom. In this lab, dichloromethane (organic) has a density of 1.33g/mL while water (aqueous) has the density of 1.00g/mL, so dichloromethane will be on the bottom and since “like dissolves like” and eugenol does not dissolve in water but dissolves in dichloromethane, eugenol will be found in the dichloromethane layer.
HPLC (High Performance Liquid Chromatography) is an analytical technique which separates a complex mixture of components into its specific individual components. It is a powerful tool in analysis, as it combines high speed with extreme sensitivity compared to traditional methods of chromatography because of the use of a pump which creates a high pressure and forces the mobile phase to move with the analyte in high speed. It is been used as a principle technology in various automated analyzers used for diagnostic purpose.
The separation was successful and produced separated stages consistent with prediction based upon solubility properties. This was indicated by the qualitative tests and observations.