When packaging a product, some materials will give off gas and fill the remaining volume of the container to a certain degree. This space above the material in the container is known as headspace. Depending on the material or conditions applied to the container, the headspace may become filled with gasses at a concentration not previously predicted. Often these volatile organic compounds will cause undesired consequences to the product and/or unpleasant odors.
Scientists use headspace analysis to learn more about the volatile and semi-volatile organic compounds being released from sample materials. A method for analyzing the composition of the headspace is known as Headspace GC/MS.
The two most common processes of types of headspace GC/MS are outlined below. Both types of analyses can accommodate either solids or liquids:
Dynamic headspace
A sample is sealed in a vessel that is heated and flushed with ultrapure gas. The gas then passes through a sorbent material which collects the volatile organics removed from the sample chamber. The sorbent material is then heated and flushed with gas in the opposite direction, to move the collected volatile materials into the head of the gas chromatograph (GC). Mixtures of compounds are separated in the GC and then delivered to the mass spectrometer (MS) for identification. This technique measures down to parts per billion levels.
Static headspace
The sample is heated in a sealed environment and the gasses are removed from the vial for static analysis. Once the gas has been captured, it is injected to a gas chromatograph which separates components of the gas according to size and polarity. The components are then identified individually with a mass selective detector. The technique has sensitivity levels in the ppm range.
Uses of headspace GC include applications like:
- Testing for residual solvents on consumer goods and pharmaceuticals
- Industrial analysis of volatile organics outgassed from plastics
- Identifying flavor compounds and odors in beverages and food products
Headspace GC is an excellent method to determine what and how much material is being outgassed from your product.
Contact us to learn more about Innovatech Labs’ headspace GC services
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