Gas Chromatography Detector: An Overview

by Emily John Digital Marketing Service Provider

The detector senses the presence of the individual components as they leave the column. The doctor out pout after amplification is traced on a recorder. The duration of the intervals is usually a single second or even less than that. Hence, the gas chromatography detector is considered to be the brain of the instrument. The detector converts a change in effluent into an electric signal that is recorded by the data system.

Ideal Properties of a detector

This gas chromatography detector is used in both GC and HPLC should have the following ideal properties:

· High Sensitivity.

· Good stability and reproducibility.

· A linear response to solutes.

· Negligible baseline noise.

· It should be inexpensive.

· Capable of providing information on the identity of the solute.

· A temperature range from room temperature to at rest 400°C

· The response is short for time independent of the flow rate.

· High reliability and ease of operation.

· The detector should be non-destructive.

· Response is independent of mobile phase composition.

Detectors used in GC

Detection devices for a GC must respond rapidly and reproducibility to the low concentrations of the solutes emitted from the column.

Concentration-dependent detectors:

1. Thermal conductivity detector

2. Electron capture detector

3. Argon ionization detector

4. Helium ionization detector

Mass flow-dependent detectors:

1. Flame ionization detector

2. Nitrogen phosphorous detector

3. Flame photometric detector.

· These other detectors also used:

1. Thermionic detectors

2. Photoionization detectors

3. Atomic emission detectors

4. Sulfur chemiluminescence detector

· The most widely used detectors are TCD, FID, and ECD.

TCD is known as a thermal conductivity detector, which is one of the old detectors for GC, is still widely in use. It is well known as a cathetometer and a hot wire detector. The principle in TCD is the change in the thermal conductivity of the gas stream. It is a simple, inexpensive, accurate, and non-destructive type.

FID is another most widely used and generally applicable detector for GC. Detection involves monitoring the current produced by collecting this charge carries. There are numbers of properties performed by FID which makes the most useful general detector.

The electro-capture detector used for environmental samples because it selectively responds to halogen-containing organic compounds.

The final take

The detector is the key element that is present in any device that is used for the identification and estimation of any compound. It detects at a faster rate i.e. within seconds hence it is considered as brain if the instrument. Without a gas chromatography detector, no one can analyze the compound. Hence, it attains such important in the field of analysis.