LimsPulse
Chromatography

GC Headspace Sampler

Heats a sealed vial containing the sample so volatile compounds move into the gas above it, then injects a portion of that gas into the GC. The standard way to test residual solvents without putting the sample matrix into the GC.

  • Pharmaceutical
  • Packaging
  • Food & beverage
  • Environmental
  • Forensic
Illustration of GC Headspace Sampler
OVERVIEW

What is Headspace?

A static headspace sampler is an autosampler that sits on top of, or beside, a gas chromatograph. The sample is dissolved or suspended in a diluent (often water, DMSO, DMF or DMA) inside a crimp-sealed vial, typically 10 or 20 mL.

The vial is held at a set temperature for a set time (equilibration). Volatile solvents partition between the liquid and the gas above it (the headspace) until they reach equilibrium. The vial is then pressurised with carrier gas and a fixed volume of the headspace gas is transferred through a heated line into the GC inlet.

Because only gas is injected, non-volatile API and excipients stay in the vial. This keeps the inlet and column clean and makes headspace ideal for residual solvents testing to USP <467> and Ph. Eur. 2.4.24.

Used for

  • Residual solvents in APIs, excipients and drug products
  • Volatile impurities in packaging materials
  • Ethanol content in liquids and blood-alcohol type analyses
  • Monomer residues in polymers
  • Volatile organic compounds in water
AT A GLANCE

How it works

  1. 01

    Prepare vial

    Weigh the sample into a headspace vial, add diluent, and crimp the septum cap immediately.

  2. 02

    Equilibrate

    The vial is heated (e.g. 80 °C for 30–60 min), often with shaking, until solvents reach equilibrium with the headspace.

  3. 03

    Pressurise

    Carrier gas pressurises the vial to above the loop or column head pressure.

  4. 04

    Fill loop

    The vial vents through a sample loop (e.g. 1 mL), trapping a fixed volume of headspace gas.

  5. 05

    Inject

    A valve switches the loop into the carrier stream, which sweeps the gas through a heated transfer line into the GC.

  6. 06

    Separate & detect

    The GC separates the solvents and the FID measures each one.

Read the full working principle

Advantages

  • Non-volatile matrix never enters the GC, so inlets and columns last longer
  • Minimal sample preparation: weigh, add diluent, seal
  • Good sensitivity for volatile solvents
  • Fully automated with dozens of vials per sequence

Limitations

  • Only for analytes volatile enough to enter the headspace at the chosen temperature
  • Results depend strongly on matrix effects, so standards and samples need a matched diluent
  • Precision is usually lower than direct liquid injection (%RSD limits are often wider)
  • Long equilibration times limit throughput unless vials are overlapped
  • Leaking vial seals give low, variable results
TEST METHODS

Methods that use Headspace

In LimsPulse · Calibration Management

Keep every Headspace in control: usage logs, calibration and maintenance schedules, and automatic blocking of overdue instruments.

See how