Gas Chromatography (GC) is a type of chromatography used to separate, identify, and measure substances that can be vaporized without decomposition.
How It Works:
- The sample is vaporized (turned into gas).
- An inert carrier gas (like helium or nitrogen) acts as the mobile phase and pushes the sample through a column (stationary phase).
- Different substances in the mixture interact differently with the stationary phase:
- Some move faster
- Some move slower
- This difference in movement separates the components as they exit the column at different times.
- A detector records the separated substances for identification and measurement.
Key Features:
- Works only for substances that can be vaporized without breaking down.
- Very fast, precise, and sensitive.
- Can separate mixtures with many components.
Uses of Gas Chromatography:
- Detecting drugs, alcohol, or poisons in blood or urine.
- Testing air and water pollutants.
- Identifying flavors, fragrances, and food additives.
- Analyzing explosives or volatile chemicals in forensic science.
In Short:
Gas chromatography is a method that separates substances in a mixture using a gas to carry vaporized samples through a column, allowing scientists to identify and measure each component accurately.