Advantages Of Gas Chromatography

Derivatization in Gas Chromatography GC

Content

i. Definition of chromatography ii. Detailed definition of gas chromatography. iii. Importance of gas derivatization iv. Gas chromatography reagents

v. Advantages of gas chromatography vi. Disadvantages of gas chromatography vii. Types of derivatization: reagents used, including advantages and disadvantages.

1. Alkylation

2. Silylation

3. Acylation viii. Chiral derivatization in gas chromatography ix. Conclusion

x. Reference; Vancouver style.

Definition

Derivatization is an analytical technique that is used to enhance thermal stability of analytical compounds that may contain polar or non-polar functional groups by adjusting their volatility to improve their separation properties for easy

For a sample to undergo gas chromatography it has to be in its volatile state so as to be removed by washing the sample with appropriate solvent at the temperature that will not lead to molecular rearrangement or decomposition of the sample. Compounds with active functional hydrogen such as hydroxide ions–OH and amine groups -NH are more easily modified due to their intermolecular hydrogen that will have an effect on the volatility of the compounds to which they are present in. The derivatization process of gas chromatography decreases or increases the volatility of compounds to be analyzed, promote detector response and reduces analyte adsorption in the Gas chromatography system.

Derivatization, as we know, is aimed to improve the characteristics of compounds to prepare them and make it easy to undergo Gas Chromatographic separation without undergoing decomposition. Derivatization in gas chromatography is very important in pharmaceutical and biomolecules like organic acids, amino acids, amides, pesticides and new classes of compounds like polycyclic aromatic hydrocarbons and fluorinated, alkylated molecules are slowly being analyzed

To enhance the sensitivity of the compounds to be analyzed.

Derivatization in Gas chromatography GC aims to provide the following;

1. Efficiency is a characteristic property of the compound to be analyzed to give symmetry for easy recognition and good peak resolution for better practice of gas chromatography analysis. Interaction of compounds between themselves or with the GC column is likely to have an effect on the separation efficiency of the compounds to be analyzed but as we now know derivatization can reduce these interactions that are likely to interfere with the analysis.

2. Suitability in this case unlike Liquid chromatography where the analyte has to be soluble in its mobile phase, Suitability is the requirement governing gas chromatography like the compounds volatility and so on. Derivatization restructures the chemical structure of compounds to a more desirable form suitable for analysis.

3. Detectability is the signal outcome that is emitted from gas chromatography detectors when reacted with the analyte. Increase in analyte or addition of functional groups or atoms that strongly interact with GC detectors increases the range at which their signals are detected by the machine.

Reagents used for derivatization for Gas