Using a Headspace Analyzer to Test For Sterility and Stability

Imagine yourself at your headspace analyzer, reveling in the delight of your waitress bringing out your house special spaghetti and sprinkling it with Parmesan cheese. This tasty treat is made possible by complex combinations of volatile organic compounds that work together to deliver the unique flavors and aromas found in foods and drinks. These volatiles also play a key role in the safety and efficacy of pharmaceutical products.

One way to ensure that these volatiles remain unaltered is to perform headspace analysis. Headspace gas analysis (HGA) is a nondestructive testing technique used to measure the concentration of certain gases in hermetically sealed containers. It is especially useful in ensuring that a product’s sterility and stability are maintained in the packaging.

Analyzing Headspace: The Role of Headspace Analyzers in Quality Control

The method of analyzing the headspace is through the use of tunable diode laser absorption spectroscopy. This is a nondestructive method in which a laser beam is directed at the container’s headspace, causing molecules within to absorb a portion of the light passing through the container. The intensity of the absorbed light is then proportional to the gas concentration.

A traditional method of analyzing the headspace involves the extraction of the sample’s volatile components with a gas syringe. The syringe is then inserted into the chromatography vial, and the outgassed materials are analyzed with a gas chromatograph and mass selective detector. This can be problematic, since it requires the injection of air blanks between each sample, which can contaminate the instrument.