Matching results from a polystyrene sample (PS) with a reference found in the GERSTEL Pyro Database. Top: Mirrored view of sample and database reference chromatograms. Bottom: Individual marker matches between the PS sample and the PS and styrene-butadiene rubber (SBR) reference information in the database.
Top: Additional match information for individual peaks in the PS sample. Bottom: Mirrored display of the mass spectrum of an individual peak and the mass spectrum of the matching peak in the database.


A clear view of details in complex samples

The GERSTEL ChromIdent® Pyro Edition software enables efficient determination of even minor amounts of polymer material and other compounds in complex samples through intelligent matching with library or database data on pyrolysis breakdown products. Even when only subsets of complex samples are in the library data, a high rate of success can be achieved. One example is the determination of pyrolysis breakdown products of microplastics in environmental samples using GERSTEL-TDU-Pyrolysis or Thermal Extraction Desorption (TED)-GC/MS.  The determination of co-polymers in the form of block copolymers, alternating co-polymers etc. including additives can equally be challenging. For such tasks, ChromIdent can be a helpful tool.

When performing GC/MS analysis of compound mixtures, searching the NIST or a comparable library or a database is normally the quickest way to identify individual compounds in samples, for example additives in polymers.  Determining polymers and complex polymer mixtures as subsets of a complex sample and reach a higher level of information requires a different, more innovative approach, however. This is the case, for example, when analyzing environmental samples for microplastics residues using TED-GC/MS and having to deliver comprehensive answers without delay.

ChromIdent Pyro Edition enables fast search and comparison of chromatograms with a library of data (database) using a range of algorithms for quick and reliable identification of matching polymers or of complex polymer mixtures present in the sample. Unusually, matrix matched standards or reference chromatograms of similar samples are not needed to reach the right answers. This makes it much easier to analyze complex samples including environmental samples. Polymers can be identified reliably and accurately through the use of specific markers and similarity indices using a peak list query.  Pyrograms of polymers, co-polymers, biopolymers, as well as mixtures such as vehicle tire rubber are included in the ChromIdent PYRO Database provided with the software and the database contains multiple replicates for many entries leading to improved accuracy and reliability.

Multiple different operations can be performed that enable the identification and contextual assignment of a compound. The database can be expanded using TED-GC/MS data or available pyrolysis-GC/MS data, including MS data formats from a range of different instrument vendors.

During processing, the software performs different operations to enable both determination and classification of sample subsets of compounds, such as a polymer or group of polymers. Color coded match quality indicators provide an at-a-glance overview of the result. As needed, individual peak information can be displayed in a mirrored view with information from the database for easy and reliable direct visual comparison.