Rapra has recently enhanced its capability with respect to gas chromatography-mass spectroscopy by the addition of a LECO Pegasus III instrument.
Rapra previously had a good existing capability based on Agilent and Perkin Elmer standard GC-MS instruments, with a particularly wide range of sample introduction.
The new system gives a multidimensional chromatographic capability, with the extremely fast scanning of a ‘time-of-flight’ (TOF) mass spectroscopy and software with very sophisticated deconvolution software. These combined features are ideally suited to looking at very complex mixtures.
The new instrument can be used for two different roles. The first of these is to have single dimensional chromatography combined with the fast TOF-MS scanning to give rapid GC-MS analysis – this is well suited to fast analysis of very large numbers of samples. However, at Rapra, the instrument is expected to be used more in its multi-dimensional role for looking at more complex mixtures.
The LECO Pegasus III has a standard Agilent GC system but a second column oven and a modulator between the ovens allows for two-dimensional separation (one effectively by boiling point and one by polarity). The very rapid scanning of the TOF-MS is essential to monitoring the output of the columns and the sophisticated deconvolution software gives an immense amount of data from a single injection.
Work already carried out by Rapra has demonstrated how good this system is at identifying specific components within a complex mixture. This should be particularly good for looking at components that might otherwise be lost in a broad peak due to oligomers or oil extenders etc.
This will be particularly useful in the analysis of rubber compounds because the extracts obtained from such matrixes are often very complex mixtures due to the number of additives in a rubber. The relatively large amount of oil/plasticiser can also hinder peak resolution in standard GC/MS work. The ability to separate and identify accurately a greater number of species will enable better quality data to be obtained on the composition of rubber compounds.
The combination of GC and GC-MS tools now available at Rapra allows for the analysis and identification of most volatile components that might be present in polymers and extracts of polymers and the multi-dimensional capability of the new instrument is particularly valuable for those really complex mixtures.