A new detector for gas chromatography has been developed that is based upon nonlinear Raman spectroscopy. The resulting hyphenated instrument uses a simple windowless cell as the interface between the chromatograph and the spectroscopic detector. The eluents are detected using a unique spectrometer equipped with a broadband OPO. This spectrometer is capable of generating high-resolution coherent Raman signals that are suitable for rapid multichannel detection.

Gas chromatography–multiplex coherent Raman (GC-MCR) is a new tandem technique that can be used for the high-speed analysis of volatile mixtures. BTEX serves as a useful and challenging test sample because of the similarity in boiling point and spectroscopic properties of its constituents. The ability to spectroscopically resolve isomers (e.g., m-xylene and p-xylene) allows GC-MCR to sacrifice chromatographic resolution for speed. The result is the analysis of BTEX in less than 5 min, which is relatively fast compared with other tandem GC techniques.