Pyrolysis gas chromatography-mass spectrometry (py-GC-MS) is an analytical method that is used to break down complex molecular mixtures by exposing them to intense heat, after which different components are separated and their concentrations measured. Py-GC/MS is one of the definitive methods for detecting microplastics in water and other environmental samples.
Simple pricing model, no hidden fees
- Fast turnaround times
- Personal service from method experts
- Competitive prices
- Result accuracy guarantee
What is pyrolysis GC-MS used for?
Py-GC-MS is used in various fields of chemical analysis to test for the presence of chemical species and determine their respective concentrations. It can be used for quality control across the pharmaceutical and consumer goods industries, where it is especially useful when screening samples for polymers and plastics, which are notoriously difficult to detect through conventional means.
The ability of py-GC-MS to detect plastic contaminants is also highly useful in environmental analysis, particularly when analyzing the presence of microplastics in drinking water, wastewater, sediment, soil, and sludge. The method can also be used to characterize polymeric materials and estimate the molecular composition of lignin samples.
How does pyrolysis GC-MS work?
The key principle of py-GC-MS is that the sample is first pyrolyzed, which means that it is broken down with heat. The pyrolysis is conducted under an inert atmosphere, as this prevents the sample from reacting or oxidizing further, instead causing it to separate into smaller constituent parts.
The fragmented sample is then passed through a gas chromatography column, which will separate the components based on their size and chemical properties. Finally, the fragments pass through a mass spectrometer, which separates them further and detects them as they reach the end of the chamber, recording their respective mass/charge ratio. These ratios can be used to determine the chemical composition of the individual fragments, their concentrations, and subsequently the composition of the original sample.
Suitable samples and sample preparation
Unlike conventional GC-MS, there are fewer restrictions on what can be tested through py GC-MS, simply because the pyrolysis step helps to break down complex sample types to make them suitable for testing without much preparation. This means that py-GC-MS can be effectively carried out on small amounts of powdered solid samples. It can also be carried out on solutions, as well as dispersions of insoluble materials. Both clean and wastewater are also suitable sample materials.
Advantages and limitations of pyrolysis GC-MS
The key advantage of py-GC-MS is the ability to detect components in solutions that are non-volatile and therefore would not usually appear in conventional GC-MS analysis. Furthermore, it can be conducted on a greater range of sample types than other similar methods. Pyrolysis-GC/MS can also detect very small quantities of contaminants, down to microliters or micrograms within liters of sample material.
One key disadvantage of py-GC-MS in microplastics analysis is that it can only quantify polymers in micrograms per liter, thus not providing information on the number of particles that belong to different size ranges. Furthermore, it is incapable of detecting certain inorganic substances, and non-homogeneous samples may produce slightly varying results, sometimes needing to be tested multiple times to reach reliable conclusions.
Suitable sample matrices
- Water samples
- Powdered solids
- Organic solutions
Ideal uses of py-GC-MS
- Detecting impurities in water
- Analyzing polymers and plastics
- Detecting the presence of microplastics
- Characterizing complex mixtures
- Quality control of consumer goods
Frequently asked questions
Pyrolysis-GC-MS is one of the most popular analysis techniques for detecting microplastics in water, soil, and other environmental samples. It can also be used to characterize complex, non-volatile samples, such as lignin.
Measurlabs offers a variety of laboratory analyses for product developers and quality managers. We perform some of the analyses in our own lab, but mostly we outsource them to carefully selected partner laboratories. This way we can send each sample to the lab that is best suited for the purpose, and offer high-quality analyses with more than a thousand different methods to our clients.
When you contact us through our contact form or by email, one of our specialists will take ownership of your case and answer your query. You get an offer with all the necessary details about the analysis, and can send your samples to the indicated address. We will then take care of sending your samples to the correct laboratories and write a clear report on the results for you.
Samples are usually delivered to our laboratory via courier. Contact us for further details before sending samples.