Parallel chromatographic systems

An analagous process for isolating and concentrating portions of a sample is the use of thin layer chromatography. Here, however, it is common practice, in the treatment of an unknown sample, to place a known standard on the same plate and to run the two systems parallel so that differences in performance of an adsorbing system from one laboratory to another are accounted for by basing isolation of the desired components from the plate on the determined position of the known standard, run on the same plate. The normally limited capacity of thin layer chromatographic systems tends to exclude their wide use for the combined isolation-concentration steps of trace analysis, but circumstances in which this technique may be useful should not be overlooked. ... 

In this mode, the eluent is directly flowing from the chromatographic system into the NMR probe. As only selected peaks are measured in the NMR spectrometer the separation is monitored in parallel with an LC detector (typically a UV detector). A peak is selected from the chromatogram recorded... 

Ikarashi et al. reported the development of a liquid chromatography multiple electrochemical detector (LCMC) and its application in neuroscience [197]. The system developed consisted of four parallel liquid chromatographic systems equipped with multiple electrochemical detectors, and the fourth was used for the assay of acetylcholine with a detection limit of 0.1-0.4 pmol. 

HPLC equipment is much less expensive than mass spectrometers, chromatographic systems could be parallelized for preparation of MALDI targets that could also possibly be archived for future re-examination. 

A reasonable throughput screening equipment consisting of six parallel reactor tubes was constructed. The system operates continuously and can be used for screening of various catalysts, different particle sizes and temperatures. Gas, gas-sohd and gas-solid-liquid applications are possible. The screening equipment is coupled to gas chromatographic-mass spectrometric analysis. The constraction principles, the equipment as well as the application of the equipment is demonstrated with three-phase catalytic systems. 

Multidetector chromatographic-spectroscopic methods are frequently also described in terms of multidimensionality. In GC detection, both FTIR and AED are used in parallel with MS, i.e. after a split. GC-FTIR-MS systems are commercially available, at variance to GC-AED-MS. The latter can be applied in the analysis... 

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