Category:Derivatization
From LEAP
Derivatization
When do you use derivatization? When you need to:
- Increase or decrease the volatility of the analytes to improve separation
- Improve peak symmetry by reducing interaction of sample and column
- Increase detector response (i.e., ECD)
- Enhance thermal stability
Gas chromatography is used to separate volatile organic compounds. By modifying the functionality of a molecule to increase or sometimes decrease – volatility, derivatizing reagents enable chromatographers to analyze compounds that otherwise are not readily monitored by GC. Derivatization also reduces analyte adsorption in the GC system and improves detector response, peak separations, and peak symmetry.
Derivatives are used for the following reasons: • to improve resolution and reduce tailing of polar compounds (–OH, –COOH, =NH, –NH2, –SH, and other functional groups) • to analyze relatively nonvolatile compounds • to improve analytical efficiency and increase detectability • to improve stability of compounds
The choice of a derivatizing reagent is based on the functional group requiring derivatization, the presence of other functional groups in the molecule, and the reason for performing the derivatization. The chemical structure and properties of the molecule influence the reagent choice. In choosing a suitable derivatization reagent, certain criteria must be used as guidelines.
What are the requirements for a good reagent? It will:
- Not cause any rearrangements or structural changes in the analyte
- Produce a reaction that is 95–100% complete
- Produce a stable derivative
- Not contribute to loss of sample during the reaction
- Produce a derivative that is inert to the column and connections
- Not produce interfering byproducts
Derivatization is a technique used in chemistry which transforms a chemical compound into a product of similar chemical structure, called a derivative. Generally, a specific functional group of the compound participates in the derivatization reaction and transforms the educt to a derivate of deviating reactivity, solubility, boiling point, melting point, aggregate state, or chemical composition. Resulting new chemical properties can be used for quantification or separation of the educt. Derivatization techniques are frequently employed in chemical analysis of mixtures and in surface analysis, e.g. in x-ray photoelectron spectroscopy where newly-incorporated atoms label characteristic groups.
LEAP provides automated workstation instrumentation solutions based on the LEAP CTC PAL X, Y, Z syringe only autosampler robot from LEAP Technologies. This extremely flexible, precise, and adaptable liquid handling robotic platform is available in a variety of lengths and options depending on the requirements of your sample preparation and injections for your UHPLC, LC or GC chromatography. Please contact LEAP Technologies on how we can help you get maximized throughput with flexible pipetting automation solutions.
Contact LEAP
This category currently contains no pages or media.
